Document 99a6ZkOvLjKKQ1jze4bMJEGr5

E. I. DU PONT DE NEMOURS & COMPANY PIGMENTS DEPARTMENT 256 VANDERPOOL STREET NEWARK, NEW JERSEY Copy No. 1 NEWARK PLANT PIGMENT COLOR RESEARCH REPORT ANALYSIS OF IRON BLUE PIGMENTS Period Covered: January 1945 to December 1945* FILE: DATE, 5/6/46 NJ3*09 Copy Ho, l Copy teas #1 ** Numerical Pile 2 - Research Office (213) 3 - Library Pile (213) 4 - #10 Building File 5 - #6 Building File 6 - Imperial Chemical Industries> Ltd. 7,, n n nv g . it si 9 - D. H. Dawson, Newark 10 - Extra 11 - ' Si i NEWARK PLANT PIGMENT COLOR RESEARCH REPORT Titlei ASAtiai6 OP IRON BLUE PIGMENTS Period Coveredt January 19-45 to December 1945. SUBMITTED BIj .ft, R. Hanke APPROVED Bis A. A. Brizzolara DATE SUBMITTED; Aarcft 23, 194* DATE ISSUED! 5/6/46 N41558.01 DUP050150584 PAGE i MmMmtMjmmm A. Determination of Complex Iron Cyanide Iron B. Determination of total Iron and Cationic Iron C Determinationof Total Alkali Metals D. Determinationof Chromium fi Determinationof Sulfate F. Determinationof Total Water 0 Determination of Iron Outside the Iron Blue B, Determination of Organic Treating Agent ? 10 10 11 14 14 IX fig HTBGD0CX1QB 'A* Standard Deviation for errocyanlde as 16 determined by the Ceric Sulfate Method B* Standard Deviation for Total Nitrogen Method G. Standard Deviation for Ammonia nitrogen to Method D. Standard Deviation for Ferrocyanide as 41 determined by Total Nitrogen minus Ammonia Nitrogen Method . Comparison of Precisions of Ceric 22 Sulfate and (Cl) Nitrogen Method for Ferrocyanide* 23 F. Standard .Deviation for Total Iron Method 44 G. Standard Deviation for Cationic Iron Method Determined.by Total Iron minus Ferrocyanide fi. Standard Deviation for Total Alkali 25 Metals Method X, Standard Deviation for Total Chromium 25 Method J. Standard Deviation for Total Sulfate 26 Method SL Standard Deviation for Total Water by 2? Loss In Weight Method. L. Standard Deviation for Total Hydrogen ;:3 Method for Water :>9 tt Standard Deviation for Total Water Method Determined by Total Hydrogen minus Ammonia Hydrogen N. Comparison of Precision of the Loss in Weight Method and the Total Hydrogen Method for Water, DUP050150585 mmmmm A1though iron blue pigments represent a sub stantial percentage of our total pigment manufacture, there has been no comprehensive analytical work done on such pigmeat. Analytical data, although not standing alone, are Quite necessary for a good understanding of the properties of Iron blue pigments* Improvements in methods of manufacture and properties can be indicated by a critical examination cf such analytical data* This work was originally started with the primary purpose of providing data for a comparison of the ferrocyanide content of our pigments with that of our compitators. The work however extended to the complete analysis of iron blue pigments. The report is divided fento two sections. The first part deals with the development of the various methods. The second part deals with a brief statistical' treatment of tbs data. It had originally been intended to include a third part covering an interpretation of the data, Since certain ideas concerned with this interpretation are still in the formative stage, it was thought advisable to Intoduce the interpretation of the data in another report. In developing the methods of analysis, the litera ture was freely drawn upon.' The references found to be of value are listed in the bibliography. As a rule, considerable modification was made of methods obtained from the literature. The development of each method Is treated separately, giving such information thought to be of value or interest even though some of the information was not incorporated in the finally chosen method. A statistical treatment of the data is Included to provide a means of comparing methods as well as assessing the precision of the various methods, It also serves to illustrate the application of statistical methods to problems of this kind. No attempt is made to develop any theory of statistics and some knowledge of such is presupposed. For a simple discussion of the application of statistical methods see, *Analysis of Variation8, ICl (Dyestuffs) Technical fleoort March 16, 1941, File No. H5824,, DUP050150586 -2' SUMMARY This report describes methods for determining the following constituents. The methods in detail are found in the appendix as indicated: Appendix (1) Ferrocyanide by eerie sulfate tetration. * (2) Total Nitrogen * (3) Ammonia nitrogen U) Total iron (5) Total alkali metals Chromium Sulfate Total water Iron outside of the iron blue molecule (10) Organic treating agent. The describee. methods were applied to a series of Iron Blue pigments, the results of which are tabulated in Table 1. (1) Investigate the possibility that some of the cationic iron in commercial iron blue pigments is there as ferrous iron such as Fe {m%2 |% white precipitate or *2 +3 +2 Fe Fe Fe (CN)^ 2 which may be considered as the ferrous salt of the acid +3 +2 , H Fe Fe (Cif)6 (2) Develop a method which would distinguish between the alkali metal incorporated in the iron clue .wwoc-'Lc and the alkHi metal simply adsorbed on the pigment. (3) Further investigate methods for detev^ini-i total water. The total hydrogen minus ammonia hydrogen ;.ie gives results higher than the loss in weight method. v.-V? If it were possible to have compounds of the species +3 +2 Fe fl Fe (Ch)6 the total hydrogen method would give high results. C i) ',t DUP050 50587 % fi r ttsaMsg, the mm&l* &s %Hem& ie piek ag as asiek Koistar a s i t miXd s i rows trwg*ratar> B2|JH>& B - - ***** 4 Q _M > ----- Ih J Z S U to ___ SSL .OaMJEa ----- sl5----- *-- ------hXL ---- - . > ___ & sM -- id L ^ ^ ^ jh a a jh a^ -- n*s--- Q; . '* >< vl-*f m pHJ&o3i H;Os & .,,. *^ V . 4* fr&* V^H t*,* osn O$^ *:?'^$i $stom$.:i $*'-i >-$*!* *Hs af> >*t Si 4A* -WMA JwoIc3I; i&l I tt os ';5' o VS vm* ht$os $Voo<J0I pi <tU V .1 1 <2 5 #5Q v $3 *rns*< *O!'8S'* ^VS$ LVt$.t*0fw#t*,1 *3 5A4*f HUI #l *< V ifi '3 toSN ; ; f3 . V1 j 1[[ crns if on <M ys IoH4f iri & * #ri tt m i> i? Mh ir* ooiiSl %toAVo ** S U> \8* f*r Vv*!i < ^* 0 3 X %0i # a t$ : <.s %IoS*| Ho 4) H H H H a H tHo 0*x fr <2 j C0M ? sA H H H H 3 1 i H & $ 3 S43 C1M^i irs 9 o 5 U*\ \ 0* sj -4$ H s w 1 IHM*SSj v141 i &* *w<2 <r> H CM CO HI CM# ^0 G <* cr* H Hm W>, &4$ CT"<i CDa H flh H cHO0 m I<Hr *t^n1 H 3 *4' 4 H + on H**. OS*> H $*& $S: vi &* H A o 9 CcrM^ <30 HI H ' a CM mCM S 3 H<N $ a a t0 VS eg sr-O1 2H * C*M* &* |4T ^OHS Ij S 1 *l 3Mfifel cr 1IW40 9 2? 1 i 3, H si $rji J * fVPVW?43l A H i3| !iL3| t SH H<** f 5 S ^i H cCnM o 1 i iH3IliHl*i* p 3i 25 J0 IN IS l| 0m iJ Jv4> al r*^ I o.5 s Q NCg o Cjj <M *V0 % >lyon* to fa v * sta rin g la aa s ir tig h t #*tair* ___________^ M L a t . . DU P050150588 ExgMiMEam 2 DsTeloomenfe of Methods A Determinate^..Gojapl^ Iron There are quite a few methods avr Liable for ciEtsrrfnrru; the complex iron cyanide iron. Of these methods,' four wei e chosen for Investigation. These methods .were:- (1)Destruction of blue pigment with caustic and titration of the ferrocyanide produced with * standard oxidylng agent. (2)Detraction of blue pigment with caustic aod titration of the ferrocyanide produced with a standard solution, of zinc sulfate. (3)Determination af.,;:ha (CM) nitrogen and express ing it as Pe * (jL)Determlnatlqip, of total carbon acid expres: :.ng It as Fe (aj6 In working with the first two methods certain difficulties became apparent and as a result, these ifafethods were finally discarded. In the first place it was found quite difficult ;,o completely separate the ferrocyanide from the ferric hydroxid s after alkali destruction of the blue pigment. When an. iron bios pigment is treated with a caustic solution, ferric hydroxide and a soluble ferrocyanide are produced according to the equation, Fe HH4 Fe (CN)6 + 40H - Fe (QH)3 + Fe(CSJg + f + n2 It is impossible to wash this ferric hydroxide precipitate free, of ferrocyanide when using the customary wash solution of 2$ ammonium chloride* This phenomenon is very pronounced. Mo ferrocyanide at all is-found in the wash filtrate until distilled, water is used. Using distilled water, it \e:.omes possible to wash out all of the ferrocyanide but the ferric hydroxide is peptized and runs through the filter before the ferrocyanide is completely removed. Using a wash solution of sodj.ura hydroxide in place of ammonium chloride also did not work. The ferric hydroxide still ran through the filter. A technique was worked out whereby the peptized ferric hydroxide plus the remaining ferrocyanide was caught in a separate beaker. The ferrichydroxide was coagulated by the addition of ammonium chloride end refiltered* Since this amount of ferric hydroxide was always small, the amount of ferrocyanide adsorbed on it was considered too small to affect the results. This technique was found to be superior to the customary reprecipitation technique since several reprecipitations were necessary bringing the salt concen tration up quite high* DUP050150589 Acidifying a solution in which reactions like the above have taken place would result In the formation, of some iron blue* Fe + HH4 * Fe (C)6 + Fe Fe (C)6 Iron blue or 4 Fe (Hfi )* Fe (CS) + 0 (from air) * 4Fe8BLFe(CN), v^HH. *2B O 4 < o / 4 6 '! 2 " White'"precipitate Iron blue Reaction (3) which produces formate will cause high results if allowed to go to any appreciable extent* Formate is capsule of oxidation by ceric sulfate as follows 2Ce (BO) + H COOH - Ce (SO ) + CO t 4- g2 S0A 42 2 4i An inspection of the equations shows that one ferrocyan:', de iron produces 6 formate irons which means that one red-ritior. equivalent produces 12 reduction equivalents or a net increase of 11 reduction equivalents for every ferrocyanida iron con verted to formate. This will give high results as indeed;, high results were sometimes obtained. Since it seemed evident that some reactions were , taking place that affected the results, and since some iron blue pigments contain organic treating agents whose effect on ceric sulfate might not be predictable, -the direct titration of ferroeyanide produced from toon blue pigments was abandcred. The method may be applicable in certain cases and it may be possible, to get the variables under control by doing further work on it. Some of the comparisons with other methods wen-. quite good as can be seen in table 2. The asthou employing the titration with ceric sulfate is given in detail in appendix 1. It is given becuase it embodies certain useful techniques* and. ideas that can serve as a starting point if it is found desirable to do any further work along the line of the direct determination of ferroeyanide in iron blue pigments. A small amount of work was done on the ainc sulfaic titration method in conjunction with the ceric sulfate me then* Here again, the precision was very poor and. since the methoc' is admittedly empirical, the position of the endpoint being dependent on tto kind and concentration of salts in the sob aers., the method was discarded. DUP050150590 -I- fhe third method investigated was the determinative of (C) nitrogen. expressing it as F (CSJI. Uhis was accomplished by first determining the total nitrogen follovdeg the standard EJeldshl technique and then determining the ammonia nitrogen ter a simple alkaline distillation. The difference was (CM) nitrogen. Here again the observation vm made that some of the ferrocyanide decomposed to give araaonts. presumably encoding to the equations. Fe (SSTg yj* + 6 Cl ... -............eS + 2^0 -*..{c o 5hJ:+ KB3 f .............. -.................-..... Repeated alkaline distillations of the ferrocyanide from tbs blue pigment always yielded a small amount of something alkslire, presumably ammonia. This did not occur during a blank deter mination* Such a reaction, would not cause as large an error in this case as in the titration with ceric sulfate. One ferrocyanide iron would produce six equivalents of ammonia whereas in the ceric sulfate titration method, one ferrocya-. iron lost would create 12 equivalents of formate. The pro duction of ammonia in this manner was small and sufficiently constant so a correction could be applied, .Employing such a correction changed the percent Fe (CHjg, by only Q.1% absolute which is hardly worth considering and serves to indicate that the method is not subjected to serious error because of tbis reaction. A fourth method was considered primerly to serve as a check on the (CSS) nitrogen method. This determined the total carbon by microcombustion ana calculated it to ferrocyanide. Strangely enough the method gave results which as a rule were 2.2% relative high. The precision of both me there was about the same. So good explanation is offered for this difference. Other sources of carbon such as carbonate?; , organic treating agents, or small amounts of organic impurities'picked up during manufacture would give high results although the blue pigments run for total carbon were supposed, to contain no treating agent. Table 2 compares the values for ferro cyanide obtained using the (CH) nitrogen method, Ce (SO/), method^ and the total carbon method. It shoudl he noted, thet in thase of the five camples tested the (CK) nitrogen and tlv: Ce (SO.)2 method are in good agreement, it should be furtbe.s noted uhat in every case the total carbon method is higher than the other methods. It ranges from a high of 5.4$ relate to 0.4$ relative higher than the (CS) nitrogen method, in DUP050150591 spite of the fact that the reason for this difference Is cot clearly understood, in view of the fact that treating agents are-frequently found in iron blue pigments, the moat reliable' method studied is the method determining the (CM) nitrogen, This is given in detail in appendices 2 & 3. The standard deviation for 14 degrees bf freedom la *0.32,4$ Fe (CRJ" Ccwparisoa of Metfeeds far ? (CM)^ teisraiaatioss Fret t& (G15 MMSm. (CB) Ce Bitrogea (SO.)_ Jiethod.,,. Mettod Calco 50-1750 _____ - Imperial A-4406 .-QrA,Q13L. 1^I97^D 66.43 67*94 66.98 b -K-d fifc&Bafl. 1105-38 entreated B-216-P Imperial X- 712 64.01 67.08 Satzm. Stand-Oltramarine #430 JAt2L Sz&um.__________ 1105-38(entreated B-216-D) Heated for 412 hrs. at J&9SSU 36.56 67.58 68.30 68.12 63.79 66.78 Total Carbon by Itircrooomoustion 68.77 69.19 68.37 65.14 67.33 ALIA 57.21 38.5? Relative ?rc.et beitresa Total Car Ce(S0 ,)0 bon Metho Method & (CB) (CB) Bitrogen Nitrogen Method Me ;hnt'I +1.7 +0.5 +1,7 -0,4 +2.1 +1.7 +0.4 +2.1 +2.1 +5.4 DUP050150592 l_3Bgj6Maiiifi&flSLjB3L3^ For th determination of total iron, the pigment pust be opened in such a manner that the complete destruction of the complex iron is assured. Gentle ignition of the iron bln* in an open beaker can do this but it has been our experience that sometimes a small amount of blue remains unchanged. * Sub sequent solution of the Iron oxide formed is often incomplete especially if the ample is strongly ignited to insure complete destruction of the blue. It has been postulated that small amounts of iron carbide form which will not easily dissolve in HCI*. Onchf.aged iron blue will not dissolve in HCL and strongly ignited F@-* 0_ or Fa* 0# will dissolve with difficulty. The' presence o*' treeting"'agents will also inhibit the destruction of Iron blue* The use of perchloric acid has circumvented all these difficulties , The blue pigment is first gently igni ted . no attempt being made to completely destroy the pigment. This is follc/sd by a treatment with EOL and fine 17.y with 72# HCI, 0;, All the .*sections are carried out in a flask that can be ,+ equipped with an all glass trap. Such a trap will prevent loos of iron by volatilisation of ferric chloride and also loss ox iron by caving it carried away in the HCL 0^ fumes. The iron can now be determined by any of the standard method/ for iron* The choice of method must take into account the possibility of having interfering .ipas present, particularly chromijm and aluminum# Titration with standard titanous chloride was chosen as the most direct way for determining the total iron, Chron .um, if present, will be oxidsed to chromate by the HCI* 0/ but eois is reduced with peroxide the iron remaining in the f&'fcdc stat*) aluminum will not interfere. The details of the method, are .<o be found in appendix A, The standard deviation for 12 def t sea of freedom is'+0.042$ total iron. The cationic iron can be determined directly by first d/itroying the blue pigment with caustic and filtering off the 1< rric hydroxide, or it can be determined indirectly by subtracting *. complex iron from the total iron.. In view of the difficulties'* .ttehdant with the complete separation of the cationic iron from the ferrocyanide mentioned in past A, the Indirect method, vas chosen as most desirable* Sample 1105-33, a B-316-D type but without treating agent, was analysed both ways. The cationic iron was precipitated three time to free it from ferrocyanide. It was then dried, igni tea, end weighed. The weight was cornetna for the chromium present as found by an independent detox ,v'.ns.:tcn, The two method agreed very well. The direct"mechod gave is.991 Fe and the indirect method gave 19.00# Fe. These figures are no t meant to imply that the precision is as good as this. It simply Indicates that in all probability, both methods are reliable. It was not considered sufficiently important to do the rori 02 the direct method necessary for a statistical study of these Iwc methods. The cationic iron as determined indirectly from the total iron and the complex iron has a standard deviation for 13 degrees of freedom of +0.095# cation iron. DUP050150593 aO' the method consists of removing all other cations and weighing what t left as sulfates* The method is ease-ill ally that described by Jameson* (Ref* 3) wherein the pigment is ecatly Ignited in an evaporating dish, the iron oxide remaining, dissolved in BCL, removed with 8Hi OH and the solution evaporated to dryness with a little sulfuricTaeld. An important modification was the addition of bromine water as suggested in Gardner (Eef, 4)* The bromine water helped to open up the pigment and ode'*r*d my ferrous iron to the ferric state* It was also observed shat in the absence of bromine water some sulfide was formed presim&bly by reduction of some of the sulfate in the blue. This causes* the formation of a small amount of. iron sulfide when the solution was made ammonl&cal. This sulfide had a tendency to run ih"oigh' the filter paper and so complicated the removal of the iron. After the addition of bromine water a few drops of 30% J5? Og^.are added to reduce any chromium to the trivalent state that"may have been oxldyed by the bromine. The addition of amaon dum hydro:! tt then took out the iron, and chromiun in the pigment. Any aluminum in the pigment would also be removed. It was observed that the solution, supposed to he iron free, almost invariably contained traces of iron. Altneugh this iron could be removed as the sulfide, it was found simpler and quite effective to evaporate the solution, containing ths trace of iron, to dryness, and gently ignite. The iron was rendered insoluble by this procedure and the soluble salts v.ere leached from the residue. One such evaporation process was gnerally all that was required for the removal of this tree? cf. iron* In all of the blue pigments encountered, no further treatment was necessary. If such as sine, nickel, or ;.Le alkaline earths are present, hyarogen sulfide and ammonium carbonate can be used to take them out, but in their absence hydrogen sulfide is not necessary. Flame tests served to distinguish between sodium and potassium. If potassium was to be determined in the presence of the sodium, it was conveniently precipitated es the potassium salt of 6 chloro-5 nitro toluene 3 sulfonic acid following the procedure of KCE-44* All of the commercial blue pigments erarfir-d contained no potassium hence this method did not receive much attention. The method for total alkali metals is describee in detail in appendix 5. The standard deviation for 11 clegs--.sc of freedom is *G048 SERag DUP050150594 Bine* perchloric mM eorvasdertly opens up m iron blue pig ment am oxtdsea the ehrosiw* to chromate at the earns time, this *tW *?CS oho#. It is essentially the same as that need for determining total iron* to ia^ort&at modification i# the rapid cooling of the ps'fl lorie meld solution* Thin ie aeoess&ry to prevent the partial reductic of th chromate a* explained by 6, Mredrick 8s&th (&ef*5)* to attest me made to titrate the Aroaats directly with & standard hr* se.lt solution using b&rium di^enylKt^ew sulfonate ae the indicator end phos phoric tell to ocwplax the iron, hut the concentration of ferric iron w.o e high that the endpoint ms sluggish and ill defined* Being e c r Ic v o I" platia.ua electrode system to detect the endpoint did--' net improve mtter'j* the higher oxidation potential of potassium peraan'.an&te was uted by adding a slight assess of Mohr*# salt and titrating the excess with standard permanganate. 1331# gave m endpoint, though not Ideal, sufficiently go; A for aocurate work* This msthod le described in detail in appendix 6. The standard deviation for 16 degrees of freedom is +'0Q2?$*Srg0e, * MMm Som ef the tteyfehod# suggested in the literature opened 'up the pigment by gentle ignition followed by solution ia hydrochloric acr'. (Eef* 4). Such a method ' did not seem to be based on sound chsstica! principles because of the danger of loss of SO# during the ignition process* The identification of sms sulfide iron using a similar prewedure during the development ef the method for total alkali metals also etanped this method as being unreliable* It is true that the addition of bromine water would oxidise any sulfide to sulfate, still co:-uv BsS eetild be lost before oxidation to sulfate. Xappelmeier (Eef* 6,?) suggested a method for the alkaline destruction of iron blue in which the ferraoyanide ms destroyed by forming the more stable mercuric cyanide couplex* He applied the aethoi to chrome greens and e found it to work quite -well for iron blue pigme-vit* Kappelmsier used mercuric oxide as his source of mercery but we found that mercuric oxide added directly worked very poorly* It me necessary to use freshly precipitated mercuric oxide* Aged material was far lees reactive * The method finally adapted is a modification of the original method of K&ppaLaeler end is described in detail is appendix 7. The standard deviation for 14 degrees of freedom is +p065 $B0P The ignition method and the alkaline mercuric oxide method wars compered Ir running two' samples both ways* As me predicted, the alkaline nertwric oxide method gave eubotaati&lly higher results, 0*80$ Ob se against 1*28$ 80* for one sample end 0.42 as against 0.62 for another sample* The alkaline mercuric osd.de method was cheeked by adding eulfate to a l-.s ' sulfate blue and comparing the expected answer with that obtained, The expected answer was 8 mg Ba 80 as against 82 mg Ba SO# obtained* This seems to indicate that the method my give slightly high results but dice the amount of sulfate in a blue pigment ia never very large, such an error my be accepted* The method ms further checked by having throe DUP050150595 *U` samples run by an independent laboratory, th plant analytical Laboratory. Table 3 shove tha agreement between laboratories which ie in keeping -*ith the variation* to be expected. 8-19I- 8D48g49 B-216-D 48321 1105-38 (Bairsated 8-216-0) TAMM \ % SO 0*9 1*3 US Plant Analytical 1.0 1*4 1.5 Shin datwaiaation ie very difficult* Moisture i'a strongly hold by iron blue and attempting to drive it off by beating, caussd'Vte decomposition of the figment before all of the eater me driven off. Toluene distillation Aeoc net ebem to get all of the moisture. It ctrv s off very slowly and long distillation periods are required* Bven ar -r around 15 hrs* a **all amount of additional moisture can be obtained for some blue pigments. Ignition of the sample to iron oxide a$g scalculatiag the lose in weight other than that due to loos of (CM)#: fi rt has been suggested (Ref* 3) This did not verb because the naWtl t.-rcre in the dependent determinations wide the precision of the moisture determination so peer as to be practically worthless* Furthermore* ec re of the iron me converted to FsO which could not easily be converted tc FegOs, hence there ms a mixture of FegOg and FesS* in unknown proportion-. A simple Ignition in a combustion tub and &a attempt to eelleot the gases evolved else failed. Cyanogen and polymers of oyam-yen were produced which clogged the absorption train and gave fesuli-E that could not bo correlated with moisture* A modification of the toluene distillation method was iris?, in which the blue pigment was first ignited while tx: the flash equipped with a condenser. Moisture could be seen along the inside of the o c e5 :s.mt wait, but when til Ignited product mus distilled with toluene, ne misters came over* Svidentally the iron oxide produced, ms able to etkferb r-r;i hold the moisture even more strongly than iron blue* In spite of the heat decomposition of iron blue pignEt<js vi e most promising method appeared to be the ices in weight on heatij?^;, - r this purpose, a Br&beooder Moisture. Tester was used* Sale instrvaont is essentially a drying oven with a bslanoe attached in such fa^H on that the easgple can be weighed without removing it from the even,- 'i'itjl, if; curves were obtained at 160*S. It was observed that the curves ell DUP050150596 The rate for normal drying Is roughly proportional to the percen'; ai*turs regaining in tbs him hmts the slope In the curve ahenli a.ii If **d eventually beccm* **ro, 1, & horiaontel li, srhea th; ,x' -,? is ftH gems* Hi fact that th* slope never becomes aero , >*. f J ; -.v 412 Jars* is strongly indicative that doco^asitioa is t?3 ir! pla Dott>o*itioxi is also indicated when comparing th aaaly,.ical\ vt i--.. heated and unhealed samples in table 1# Tnc fact ..hu v txii^.0 x*')& . th* curve is essentially linear surest* that it ray be possible- to correct for the less in weight due to decomposition of the Mue. f Make this correction, one simply seeds to extrapolate the linear per.! ef the curve back to sero time# the percent lose in weight as iHciea^ii hr this extrapolated line is the percent long in weight corrects! for* the lose due to decoopositleiu Graphs 112 show typical curves. It should he observed that tin; decomposition ratals lew and in a ease should introduce a largs poa -rive error. The toning blues are in a class by thestselves with a distinct.-..;' higher decoapoeliictt rate. 0-48031 is Imperial** 1-44^4. c-4759,:. is lagierfal'e X**?12 Both 0-4?5?2 and B-15HE> are toning Blue. Grajjfc 2 above that the decoapoeitlon rat remains essentially the s, t-sth possibly a slight increases oven up to 412 hrs* This method ms found to give results that compared wx-ibis. experimental error with the loss In -weight after drying for one hr. rfc l60*F. feasible exceptions are toning blues where the dceoapotit-.:];; rate is abnormally high* This method iaplles that the k-ccspoaiiio:; rate is the same in the presence and absence of water. It la e.t he'dempirical and there i# some evidence to chow that the method gives Ic- rsuits, la spite of its shortcoming, It is still a goad control method and is considered superior to the toluene distillation method. Th* method is described is detail in appendix 8. The standard deviation; for 1? degrees of freedom is 40,l64^Hs0 Drying over sulfuric sold at room temperature in a vacnv?* ms ales considered. Here the shape of* the curve ms much the came a-, when drying at elevated temperatures in that there wee a rapid iaitiil lot; in weight followed by a leveling off 'of the curve. Graph B shorn a typical curve. The attempt was made to shew that i-t was singly a c u p of time, and vacuum drying would give th same answer as drying trs elevated temperatures. This was not shorn because as seen by rsferrf.;.^ to Graph 3, even at 1600 hrs. the less in weight had only reached 4*6? , Referring to the ourve for B-152-D, Graph the present Eoisture by the extrapolation method is about o5$, It should alee be observed however, that the vacuum drying ourve is till rising, and all that " m be concluded 1# that no essential difference has bean observed in the type of moisture driven off duriiig tacuua drying as against that iixtrsx DUP050150597 DUP050150598 DUP0501 50599 DUP050150600 off faring drying t elevated temperatures. The dopresBion in the curve at around 300 hrs* we brought about by the inadvertent lir.-M03*? of tho vacuum allowing moisture' laden air to enter th desiccator It dearly illustrates the extreme care necessary in keeping these dried samples assay from moisture* Another method considered ms the alcrooonbueticm method for total Jiydrogen. this method after correction for the hydrogen from the W4> would give that duo to miter* Unfortunately the preci si .-a of this method was poorer than that of the lose ia weight method hut .. I is sigaifieient that in all oases the total hydrogen method gave big.-:'?" results* Table 4 eo^ares these methods* van*'*.............. Sttspls *HbO by jtasO by Total 8- Lose in Ammonia 1 Weight Eslatire Percent Biff. Ratio Difference 1305-36 Untreated B-21&-S Gales 50-1T50 0-47418 Xx^oriaX A-4406 . 5*45 _... ...4*9<L . . ....^ajr. .1*112.. ,.10.8 , ... .... .35....... 1*075 wjU3- r-v--r-r-............ B-197-B " SS.-48245....... ........ . ................ ,..... ......4*35...... .1*9.9...... >451 ... M*2.............. B66i> w~md>&_________ _____ . ..3*02..._ JlmlfigL . 3*.9.............. Ii05<8 Boated 6.22 , 5*66 2.56 T l.*452 . 36*9 iB^seri&l -712 e-jja{jSSL._...,-r--r-....... 11*17.... ........10*60...... ,.5? Std* Ultramarine 1.054 .. 5*2.............. #450 Qz4$m___ a&u&o . -JAj SS--.._JL*SS_ 1.145 The standard deviation .for the total hydrogen r.sthos'i of determining BgO is j; 0*668^ Bg0 for 8 degrees o:" rroedoE which r.tanione could expect dlffereneeane greater titan about 2*0 arousal 3J`> cS t:.i infinite number of trials* The feet that the total hydrogen suited -. consistently higher than the loss in weight method is sigaificicnt bv.h there is insufficient data to tell much about the magnitude of the difference,. This is because the total hydrogen method has such poor precision* 0 ;$ can conclude however that the total hydrogen method gives higher rec-h.te* DUP050150601 G* .the.iron BXue Molegvi^ It is conceivable -that come of the cationic iren in a comaareial pigment Is there simply as a basic ferric salt such &s the sulfate# os? siaply ac a hydrated oxide* The problem of its detection :' rad difficult by the feet that iron blue ie e strong adsorber and rtay strongly hold on to sueh cationic iron. Boiling with hydrochloric aoiu caused aerne destruction of the blue# liberating iron from the pigaent molecule# henae that method of extraction could not be used* The method developed involved the shaking of the pigment in an automatic shaking device with 8# by volume hydrochloric eof.d (00 sal H*D 20 si Cone. BC1) An overnight peri-.) of shaking vac shoe m sickly for the sake of cenvmienso. The method probably glree ley results but in view of the fact that the amount of iron outsido of thrhluc was found to be quite wall* a large relative error could be tolerated without seriously affecting the results. & maple 'teat had boon deliberately heated to cause gout decomposition ms completely amlysiaed and the amount of ce.iionln iron eutsid of tKe iron blue molecule deduced from a consideration c-C the equivalence balance gave a figure of 35*9^ FegOs. The direct determination by shaking with hydrochloric acid gave 34.7^ FegOs ~o the method probably gives results no lower than 3^ relative. For normal sample* the iron found outside of the blue amounted to 0TJ.tr several tenths of a percent FegOs hence the method me considered suitable for this work, for the complete analysis of the heated ?nd unheated sample see Table 1 Fag 3 * Some attention was given to the possibility that some of this iron sight be in the.ferrous state. Mo definite evideneo could b fou.-d for soluble ferrous iron end if any was present, it was present in very email amounts* He ferrous iron outside of the iron blue molecule ms found in a toning blue studied* Blase there la fairly good evidence that incomplete oxidation of the ferrous ammonium ferrocyanide takes plx.ee |.n the manufacture of toning blues* we can conclude that this method does sot measure the ferrous iron in ferrous aamonlua ferrooyanide but is a true measure of the iron unaseooiated with the ferroeyimlde. The method' is described in detail in appendix 9. Work had been done back in 1942 in developing a method for the determination of treating agents such as naphthenic acid in iron t-iuc pigments* This method* (KCR-119) destroyed the blue with caustic wad extracted the treating agent from the acidified filtrate with potroltv : ether. A straight extraction of the pigment with petroleum other in Boaklet extractor did not work* presumably because the iron blue so strongly adsorbed the treating agent that the solvent could not rrnyrs It* The method was cumbersome and consumed a great deal of the cpor.;Virs time. Treating agents have since been added to iron bine pigEont? DUP050150602 that sir* alkali insoluble hence simply extracting th acidified f.ultra;; 9 would loo ih treating agent ia the ferric hydroxide precipitate-, ifcj ~ required a modification of the method to include the . , treatin a?::;'at that sdght be present in the precipitate hence the method became still mere euaboroone and tia consuming* Work mas done in the attempt to find a mixed solvent vM.cn could atrip moot any kind of organic treating agent directly fret*, the blue pigments A # by volume mixture of acetic sold in chloroform (5 sH HOAG * 95 ml CEBlg) ms foudd to be suitable* Such a mixture mas superior to chloroform alone or to a $j by velum mixture of fictti'-. meld in diethyl ether* The acid medium produced by the acetic ac:.d Ji convert any salt fora of the treating agent to the mor* ohlorofom eel Vi.f. acid form, hence inereaee the efficiency of the extractions 1 24 hr, extraction period urns sufficient to remove practically all of the tree Via.-; agent* One sample studied, hied quit severely in the mixed sclvejv Xt did not bleed in in aetie&eidther mixture, but then the treat!;:* agent could not b completely extracted. To get ground this difficulty the saaglo was allowed to bleed ia the acetic-acid ~chloroform mixture The chloroform vae then evaporated and ether substituted* This cause! floeeulation of the blue making it possible to filter* The clean fi3 , -,vt e then contained the treating agent* The method however, gave scwewfc&t ' w results. The flocculated blue pigment still contained sox treat: .-ig a.;jnt* Jn one cample tested, thistamounted to 9*4.of'treating agent or to 0 treating agent ia the pigment* This brought the amount of treat!:v. orvit up from 3,47% to 3*7#* The overall time required for the Soxhlet extraction method l.j longer than for the KDR-119 method but it ?qui* less of the op orator, 3 time* The following description of th brief experisieate poi rorsj'>tservo to justify the claims made for the method* Solvent # by Yol. HQA in CHCls 3 grams B-2I6-D extracted 16 hra. yielded 3*5# extracted* Additional 8 lire* yielded 0# extracted* Repeat for a straight rvn of 14 art* yielded 3*6# extracted. %MMaML SoXTffitr * CM)-Is aXon# 3 ftrams B-216-D extracted 24- hre* yielded 3*3^ xtr%eted Metoi* This i lever then th results of experiment ! Sxaerimeat 1 Method aeoording to HSR-119* Sample B-216-G 2*# extracted Hotel- This ie much lover than the reeults of ospoi-i sat 1, DUP050150603 >iy~ Experiment 4 Solvent - $ by Vol. HQ&o la CBCls 3 grams sample B-16&L-D extracted 24 fare* yielded 2.9'?$ extracted* The extracted pigment me examined for regaining treating agent by decomposition with caustic and extraction of both the acidified filtrate and the acidified precipitate. The amount found me 0*G9% treating agent* Hots**" This indicates that for all practical purposes all of the treating agent is removed* Borne evidence has been adcumulated which indicates that it is difficult to extract the treating agent from iron blue pigssente, that are high in moisture, (10$) Better results are obtained if the moisture content is brought down to ar ound 5$* This point sill bear more investi gating* The drying cannot be accomplished by heating the pigsent because some of the treating agent sill be driven off* Drying over sulfuric acid in a vacuum must be done and since this is a slow process, the total tine required for a determination is increased by several days* The total time required is then around 9 days but a good deal of that time is simply extracting and drying and does not take up the time of the operator* The method in detail is given in appendix 10* ii I&U&MSAS& S-IrM, -Ms For a simple discussion of the use of statistical methods see Kef* 8c Mo attempt mill bo made hero to discuss the complete eignificience of the statistical terms used and reference should be made to the above mentioned reference or to some standard text m statistical methods# The follenriag discussion simply defines the terns and indicates their application to the data of this report* The*1 Standard Deviation*, designated by the symbol * is a m@ui.iur of the precision of a method* A large s moans poor precision* Thj square of the "Standard Deviation^* en is called the "Variance?*, V* Tha best estimate of ie obtained by the formula* v* ^ Degrees of Freedom The "Degree of Freedom" (tt*l) is defined aa on lees the number of independent measurements n* The "Sum of Squares" ia an abbreviation for 'the sum of the eq;-v res of the deviation of the measurements from their arithmetic mean** ) {'n^ - )"' * Sum of Sfipja.ro* wbovz wt * The imivi.d^el y &3.u * of the m mz&mrimmnt* tT *> of mmMvrmmnts* w & kzitbimilu 'man tho n k DUP050150604 TIi formula' fos** *T* %hm becomes, 2- {Wj4)ts v _i^L,,......._.. Wl Another formila for uhtoh is &tbaaticully ideation] with the one 4ut given is, a *-*> a a . %" / t* i*l __. i*& f^ & isHL Thi*$ equation it tiiapltr for l&rga aswnmts of data became& it aoe &ei involve an. mirage birfe Biaeply tha square* af th<a *u a.nci tn auat of the eqju h t m* e ** i * V Ihe dsta of. tills report oastats of relatively few mea irw ; Bad# a a number of different samples* In this cage the hem set;.-sir r le gives by the %% He. u-', r: (^45* .* (jy5$* ; 5L'(yi4)ft 4 ;*. <*4) -- i*3t iul il iCL j^nj' * if w 3jf > jne ** Xj ^ /ft4 w Xj *. ""** aa^f n%$ n$ n& *** * The aiaiber of detormmtiona for deeigsmtedf Xt 2* 3$ t *&* m* w# ** * x y9 n indirtdu&l ma&ctxrimeti$& of the 18 2j. Jt 4 ' amplee Aritteetie means of tint values trjrcFti-/ - h i ** wi> %h . Since the standard deviation is not dimasiohless tut carrier the same dimensions &a the terns f; oa'which it is derived, ehangitsg iR oniit of the terms ill prcpertionstoly change the value of the standard devotion* For scample* "**} for the si* of Ce (504)a eolation required to titrat>.the ferroey&nide derived trm m iron blue pigment is * OaSy&jgU If it is desired to express the results in terns of present Fe (CH)$ iastsac rf nl C (&04)s the standard deviation wuri also bo changed to the cc-sr unit fcaeigju* 5hs average si of Ce (EO&Jg is 30,6? 1 and this converted to F# (CU)j is 65*66$* the standard deviation -<#111 tee changed necorc.: .g to the formula *65*66 * *30.65 * 30# up or W.M * *30,65 1------ U&i&l-----` ( nr\ , .J V' c ' > > . M DUP050150605 0 ^4 1$ Thie seethed of treating the variance and standard deviation becomes- necessary shea tho variances fro* two independent methods :.rs oosblnSd to give a tMrd variance for the combination of the two method" or idhe the variance# of tire method r to bo compared* The use of average figures la this maimer will introduce erne error in the st&ndai deviation and variance particularly if the Individual neasureoente vnrs considerably fro wspie to sample* The variance of a determination which is in turn dependent on ether determinations will change as the asagaitude of each of the dependent detersdnatloaa change* It is sufficient to use on average, recognising its lisdtations and realising that the variation betweoa maples is not enough to invalidate any conclusions drawn fro the datr lhn a single sawple is considered, it becomes possible to mm the magnitude of the determination of that particular eaatple in detersirirf; ths proper basis for the variance* This should then he done and theaverage not use* It is to fee understood that whenever the tern standard deviation or variance is used, what is really meant is the beat set'imt . Of ths standard deviation and the best ecrtlnaie of the variance* The true standard deviation and the true variance can never fee obtained because then imply and 1finite amount of data. The fact that a relative a snail nusber of NsamxraaMsits are nado is properly val.es into oonsidcvatf <> in the statistical tables consulted* Other statistical relationships used are that the variai.ee 0,'f the' sun or diff* of two numbers A ft B is equal to the eua c-f tli variances* The variance of the avarag of a deteradaations 1b 1 times the variance of a single determination* This means that for " a deters&nation in duplicate, z or * *-lsi^af> BetcrMmtion) yTf It is an interesting obeorvatien that the variance of the difference between two sets of duplicate determinations is the same es the variance of a single determination. let let a let fs of determinations< then V& since % V or DUP050150606 ~a This relattcaship is useful Is cross cheek wrk where it le desirable to have sens Measure of the expected deviation between duplicate sets of detersdsatiotti* A fttaagard Bgjatim..l<^..^ Sulf&teMethoi TABUS H 1SW1B Me. of Measure- Mi of Ceric Selfate Required gflralo____,-- JMgfel-. Decrees Sua of of 1105-38 Ua~ treated --X-- ~ . 30*406 30..43U.. 30*45.___ _-JSaSL.jajSIl_ A_ m 4T988 ...a____ ....29.0.5. 29.01., 29.10... _____ 29*06 ..0*0024.:......2 , B-197-D SB 48247 7 31.50, 31.31, 331*70, 31.G&, 31.lS.3O.8i..^,JL0JL -31*20- 0.4335 . _ Galoo-50"1750 0-47,418_______ 4 .._.308l*..31.0Q..il*Q3.*...3PJllft. ... -_3S42L.0.*342.2..... 3...:_.._ laperial. - A-4406 C-48031 ____ ... 31^..JKU40,_3fiaffi_ _ J&_____ 0*3050 _......2 _ JUlks&LI2SSl L^5 Ssi^le aa * 152*62 * 30*52 V * JbMLTM *0.0?231 - )fc *07231 * ip.2689 ml 0 (80)& As average percent fersccjanid i 62.0*$. The variaace should then be changed to this basis* ^62 *05 118 *07231 x * {30,52)" *62.05 ' S,8$ te>05T 0.298? - 1 0,54687! 5b (cii^' ' DUP050150607 MBamjmmmmM, So. of Haaeure- Begrr. meats stl K& QB* eq(uiml<mt Sum of of ..tendt*.._........ -J*._____JfiJBa diatillea _........ ^aloo 50-1150 .._ ....S.ouarfs 0*f418 208g*..28*54... __28*J1... _*05f3. 1 Sale 50-40fo (felgOlQ____________ .2.. _-sMz* ii*M.. Ii^perial 1-4406 28,04f .*ooeg.,..., ...,a. 0-48031._ ___ ......,1..__ .,,..^9*3^..^.9085... 1 S~i&t49.............. ...... 1....-.. -2&42*.2ftM. ... 28,10 ___ 1. 8-66-b ______ -. .. .. 27.08 .. , A45_ 1 1105-38 Untreated 28*82 $--2jt6^0......._.. ...... . ,..4...... .... .28*78..... .0117 B<46feWD lot ....... ___Jt____ .....Z'lM... ...*ooi:i.... . - B-216-B SB-48321 , 2 ... ,22.24.-2**98 .....27,10 ,0288 Stand* Ultra- marine #450 4 29.2% 28.85* 2$95 Q.-48249.......... ..... 2ag>arlal X-712 __ _____ _...29.00... ~c&2L~.. 0-42532____________ .2____ mm___ - ' _4ML-S2L_. ~r-2&SSL__ 1 Saiagle twain ,.2S0.1Q...... 28*01 ral 10 v* JbWZ-- * 0,01454 14 s 28,01 To.01454 *0,1222 2*1 1?? OP. Sines -this trarlaneo trill la e& later in eoaaeetic*. tlv;'- v :. forroeyaaide determination* It will be useful to stress it it-. p^vR1- ferracyaMid units. Ibs total nitro%m wafago is 8, 'TM-: wiusi stressed as ?iToey^3Si&e beesreg 73,36^ Fe .*** * 014^ * -JLBs MIL ,JW (28.01)2 %,56* * 10^ . *Y0.1025 " + 0*320# ? DUP050150608 Sstfraaalng tfae reaalt* la tna total nltroccss, %ao " * 01494 * C2B.01)8 %*I6* 0,0161s 29.20 *10*01613 * Jp.1276 % S 0 Standard Begj&tAon ter Ifettogi SIUJL gffiifeMiM: H. of Kaasara- Begre#*. ts .gasla ......... a ,, al Ha M to te <tf * |pyri| F1*|. Kt Celee |0-lf50 S4MU________ ,1 , _JA*52*_X4*5f_____ . _M*53.. eiw 50-4070 feripao-- __ 2.. , nLa*43*3$ _ _____ 21*42 . G*0C&L_.......... k.. _ Xa$rlal 1-4406 6-4^31............,2.,.,... . .j a mma a i. .'__M*SSL.-flaflflfig_____ _2--. .. :* Eg ui *-00 Sft*Mt4i.___ _ S-6&D ______ 2, ` ..13*.85L 0*0002 ,... 0.0008 1. 1 Thereat ed iSZAfa.n.--------1-1661*4) ifftt flea.. ..... _ 2 .....ll*m*..13.*5i.....:.... .._ B-2l64> ss,, 48m ....... , 3 ..., MJ&M&OSLMZ& ..........M*s55.....fl.*Q35i_______ ......... . Stand* Bltra- iMurlBa #456 A___ Xaperial X-722 jat3a-ii*2flfla- j . S=aia2-__-3u TWM.t. 21 JMhJSbgL JK2a3S mm.. 146,40 0*6455 'U 8af>X Mesa 143*40 m 14*84 al IQ *14*84 * AMSS. - 0*004336 i4#g4 yo^S6^ *p,f)6431 pl He OH DUP050150609 *r Siae# thie wiefifie will to** use* letter to calculate tis variant* of'the ferroeyeaid a* determined toy total aitrogea mknm asgsaala, nitrogen, it will to useful to express it 1b percent fwr^sair..! Sjf**gf^sS the average ammonia nitrogen m ferrooyanl.de plr't.e 11*3# \C8)g Ttt.31" Q*0Q4136 x v *11*31 * 0*002402 *H*3JL * V 0.002402 * O.Q4$Ol jfre (C% Sar@8ia* the^resuli# la tenet of percent M4, where the average value i# 5*fS 0*004136 x 1^1^,* ?5*t6 * O*00062f4 #5^18 *t 0*0006274 2P*QZ$Q$ m& Impressing the reeulte in terns of %0 which will toe used in the total hydrogen method for HgOt Vu,54 * 0*004336 * *11.54 " 0*002501 (14.84) 21.54 VoIooSl $>.05001 %0 0 Standard. y^tWMW MiBa-tesdBl&.mix`<?xgjL Method the variance of the mm or difference of tro measurements la given toy the equation* *A$S " *A % Applying this equation Press XI* B* ^3.36 *or totel nitrogen 0.2025 Frew 33* 0* ^23.11 *or a*oaia altrogea * 0.0024 Therefore Y73.36 ,, 11,32 0.1025 * 0.0024 ^62.05 * 0*1049 for (CB) nitrogen method 62.05 *70.1649" * 0.3239 55 F* (0% DUP050150610 It ilU. alse be desirable to express tbs results in ts^^i ot % ? because this ga$&Qd is used to determine the cationic ires.* The value 62.0$ r* (CH)6 * *<P*lva2nt to 16*3$ ** *1646 8 * 1049 * .Jlk3#-- (62.05? *3.646 * 0.007292 X&46 *y*0.00?292 - *0.08539 * F *. ffftfrwaft ,i^^.l{^Xi2Saas4aa The atatistie&l approach to tbs problem.is to ccrayar* tlx.- variances sad then through the sea of the tables (Ref. 3) ascertaia whether the observed difference can be considered elgnificient. Obftously for a small number of determinations, the variance differone? must he larger before it can be state* that tbs difference is signified -m and not due to the normal variations sheeted with small amountb of d.t-, Hence the decision as to whether a diffarer.ee is signifisient or ret depends not only on the sagaitude of the difference but also on the degrees of freedom* From II, A, \ for Go (04e Method * 0.2989 for 15 degree-* ef freedom. From II, B, ?a for (OH) nitrogen Method 0.1042 for 14 degrees of freedoa. F.(l5 degrees of freedom) Tg(14 degrees of freedom) Q 0.104? Consulting tbs tables for tbs $ probability point ^Xt -h , a Halting ratio for 12 & 14 degrees of freedom of ?53* The table does not give the 15 & 14 degrees of freedom as requested by the eata but it would give a limiting ration of even less than 2.53. Me tan conclude then that the ratio 2*85 is signifioient and therefore the (CM) nitrogen method is more precise than the Ce (SO*) method, 'she signifies,eace of the $ probability point is that we still r\m thf> rii.:. of being wrong to the extent of 5 times out of sory jbOC eJteh de j ;'.*;1o v : made. In ether words, $ of an infinite number of ratios jabaervad would be equal to or in excess of 2*53 even though the true rati^"vas~^-- The statistician must set bis risk. If we had wanted to be- wrong *ly 1 in 100 times we would have used the 1% probability point and the limiting ratio would then be 3*80* Ibis is in excels of tie observed 3.85, hence, the difference could not be considered elgnificient. A a : rule, the $f* probability point is not considered too much risk in such test of signifioienee. DUP050150611 TMUB 8 mam ytWijhsgi---------Calee f0-lf50 0-47438 Oaloo |0~4Q?0 C-4SQ10_______ _ ... Imperial 4.-4406 CL-4SG31 ___ ____ *m4 1 H, of Measure- al n Ola <*tsim\ei Stsa of Inmreit 2 40*48. 40.48 40.48 0 .4ft*2Q^..35*M._____________________ 3975r. ,ooso. ..2 _.. ..... ~ .40 40*20 r.. ....... ,....... ....., 40.8? ,oopx Or. fy, : : -S8d HLAfSM______________________________...r............ 39.20 39.20 .0001 : 1105*3 jjflrifrMstad 2g?2l6">__ JL............. ................... -J0.*2-4P*lt.. .... _...... B-1M1-D 49*16 ............. I*et 1303----- . . _ .___A_____________..38*89 . 39,02.... ,,..... B-216-9 38,91 .0005 ftji&a .....2..............................___....... Stand* Uliramrins 39.3. 39.42 39.36 *00^2 Mm 0-48249 A 37*30, 37.36.... _________________________ ............,,,............. *-252-0 37,33 *0018 ,,: let 823 2 ^37.,30A..31*30 ,37*30 0_____________________ ......T...............r.T ..................... Imperial X-?12 fc^lSSSL ___ 2_____________________ - ...,. smL.___ ' -It-.___ 36,82 36,3 ,0002......,,.................. T. .. : J^^LsuliL~*mL___ 1 Settle Mmx. *VIP_*74_1*iW_eM4MR3ViKMQMlIM36..M.. u3^9^*12 42 v *02?8 13 a 0,002138 ear * 39*12 *Yo 002138 * + 0,0462 Hi a CIS Converting te the te&sio of the storage percent total iron of 35.6#, ^35*67 ** % ?356f " O.Q01f68 (39,22) e35*6? >m001?68 * 0.042055 total irca A DUP050150612 fha mrlanee ef tfe s u m or difference of two aeacmreiia^te is gives, by tbe equation, %1B *%* *8 Apt2^ig tfefca equation, Tram 3X, S' Prsa XI, 8 fberfere ^*Sf ** total iron * Q.001T68 %6*34 feeriwyenlde ires 0.007292 %6*3t * 0.001768 + 0.007292 f19 #31 " 0*0090^0 *i9.31 m^CScSoST* >.0952$ IT B _______________ _ HiUL b o * or Measure* 3rt a Milligrams of Alkali ?J6S:''S-J Su of of Calee i r* ---------- C-4 8030 fa^eriad 1*%4$K .2 C-48031 2 ]f=OTS-- ----------------- 08*4824$ 2 lOTST "" 88 47988 iiG^**3S 2 Gstreeted B-216-& .... 3 *;%+*>} 20*8* 22*9 ___ m.x,.3& _.. ...... n r2jN&Lsp] 24#6 28.5. 27.2 18,9, 18.4, l88 xsmtf-m *<* 1Wf . ,>fcK* iv-??TMu?n:i:-:-i 2.21 304,2 o,50 24.9_ 0,13 ^_ jt 27.9 16*7 0,85 _____ j l _ 0.14 t Wfc 7303 2 ....... M*9.*..,,.^5*4..,..,........ 19.7 0,13 B-216-B 88 48321 2 18*4, 16,2 17.3 * f-4* 8iaacL MCraasrln #450 8*4824$ 2 12,1, 14,3 13*2 2,42 faperial ~fi2 S 18,1, 16,0 17*0 2,21 "H-- w-_____ ",`Txsry~~~Ts^r *3 X 1 3; Mwa per sample ?21*69 " *2&L 10 * 21.6$ 1.202 DUP050150613 n Mllli^ra** ef alltail *tal sulfate ar converted to % SagO hj the ag alk* sulfate 0*04364 $ MagO fo convert t&e variaac t a $ JtaaO basis it sost be mUiplied by {0*0*';; 64) * 1*202 s (0*04364) * 0*002209 afMfjP 0f 0,00228? * x O*04?84?( KasO * j^ac. X4BUE w BO* Of MaasureKsnta R Precast Ohrtwimi a Crg 0 Degree te of ei Mean Square rt4-m Gale 50-1750 0-47418 b -i ??4> @0-46249 BZf&B---- m 4g88 a 6 2 --4^?!Sr--.. . ...r. 0*208 0.000242 0*122, 0.123, 0*145 0.129 0,003149 1 0*264, 0*319 0,292 Q .001513 _, " _ keUpOl..... ........... B-216-D ................ 2 4 0*217* 0.222 0.275 "" _ 0.205, 0*275, 0.264, Stand* Oltran&rln #450 0-48249 Imperial 1-712 ,,~JL.____ l*00f, 0*933* 0.901 fefflfflj-__________ 1105-38 Waat&L,,.........,,___ ... 2 1.571, 1*571. 1,566 0*250, 0,250 0.220 0,000013 1 0*255 0,00338.1 0.974 0.002955 4 ' 1*569 0.00001? 2 0*250 0 1 wm$ 24 3*977 0*011270 ,'> Saaple Baaa 11.521 0*49? 24 T 0.011270 . 0.0007044 16 *!.-, ..................* ^3*02655^ CrgOa T 0.0007044 I; DUP050150614 I 1 t AI I J tglaLJjq.f mm n ^ 8md4_.. _ So* of Beterxtmiioag ... .... % ._.........K of Be 80f t :.' * Stm of . Kmh Boit&rea *Tf-.<, se&amhsvMtt Galcte 50-1150 S-47418.... _..... ............. c& jSIfO fe&a?- _. ,_____ j^erial 6-4406 ft-4SG3JL______ _____ . 94 2 -Mel* M&*-lS2 ....... 0*74 . -jg...._ . ... _ 8^8,._............. , 8*6 0*50 . 0*18 1 ____ . 1 m*m#i ___ . --JL. _-- 2SmA*. __ . - .84*9... 0.50 J. ...___ 8Pa4758__________ _--J -____.......4.9*2*..48*9............... 49*0 0*05 3 ..-1... _... . .43*6, 44*5............. 44C 0.41 Im-**4t*?t- * . >* B-1661-D tot pm....__........... ~I_ _ .......32S* 30.2.....r ....__________.8j i6S.__ _ n -4t^ifcJbf2r*w 8r4S321_______ ____ ... 2L,, Stand* Ultramris* ____36*4...38*1 ,...... ... , -, -l:ir. 3? ^4 1.81 r* 4.m _fi-48Ml. E-152-B - t-.. -.....___It.. 8jLi.................. ... _..- 7*8 0,18 Yfc*1**. h******* X*ft..8t38. _________.... 3....:....... ___.2^.6............................, Issperi&l X-fl2 2Q0 4*7 20.66 t'i >*&. * ** !V ******* .............. ....... 4 ____X4*T 18.2 21.89 HKHULB JKL. --fitted____ _ 271*2 J2k2L~WW*- " *fc:4r*^ 8**ij X fitea * n .271*2 U 24*7 V* 14 3542 ...... ......... +1*88 m Be SO* 73*541 Milligram of fcarie* eolfate are ecnTarteS to percent Ce fcy : be *K B* $0* X 0*03430 #a To eeavert the yarlasee to a % 80a hais it mtet he nalttplted try (o*'.54.30)A T^bo 8 3,541 x (0*03430) a 0*004166 ^SO$ a*/0*0043,66 p*o64l>3f.$0& DUP050150615 * Irtar. to, tom l&JfrAgttJtettsi T&m 12 no* of Bwfessfssiasi"* tieas Fsrossai less in Weight 1 hr* heatlag at 160. Keaa &vm of Sqfuare Oegrea* of Fjoe4o ^aico b-lf50 ................................................... 4 4.65, 4*55, 4.50. 4.T0 4.60 0.0150 A_ ..5JQ..5*5S, 5. .______________________________ .....-- 9rif& A-44q 6 J 3*2S*-_________ _________________ .........................................................- 5*55 5.58 0.0050 0.0013 *1..... , n vfrtx-Yv'>*'*<*nmr.-4mc "vntfaw*r*V 3 y r* f ! 1i ..... 2 .......... ............................., . . 4.35 0.0050 ,,.. i,,_ 6*55. 6*65* 6*40 4.90, 5.15 1BKfepfiifi ?21fe# J.....-- ...............................~ .....4.#1Sj l . 6*51 _4+83- 2 3 WJ36L............ __ t-- jyfi___________ 4s q B-216-0 4.45 0*0050 ............ JL.,,...................................,, .......... 8B8t321 2 AWSHff *r\' 4*^0 . , j . 4.92 ....ObGOXj I .. ...... 1.___ 8t&. 01tramria #4 042M___ 2 J1.0a^,4.CL.8Q._ r___________ ___________ ._ ..... ...... _.. 1Q.9Q. 0.0200 . 152-9 i- ?B* 238 JL.............................................._________ _________________ Isporial JU?12 T.98 9.1013.................__........................... 1 ... OrM^SL._ _2^ ____________--..... __________________ 10.60 0.0200 1 ........ ____ a________________ --la. U*m *er #eapl -68.09 11 * 6*1$ H*0 T6tM * -rrl^Bl-n- * 0*02682 ? 19 $#1$ -if 0.02682 +0*163856 Hs0 DUP050150616 1* ftfHfflfryf Buttiafeloa ** XvireMn ttetho* K1L IffilUiUB Sas^l *#. of iitsst m Pereest Total Hy&regoa D Su oS of Squares T 110^-38 BatroatM .S-llfirlL_____1....... .... 1.67* 1.61 1.64 0.0018 . U05-38 (Bcatod) KatroatM ... ................... ... ... 1.!I8j ... 1*58........................ 1.68 0.0SW Calco 50-1)50 0-47410.... _..... ._ .................... 1*1.4*.1.55____________ 1.65 0.0180 Xa$>erisl JM4406 M8931..... ... ........... _____ i,______....A*10jL..l.f6f............ ........ ...... 1.69. ..O.GOGjJ ... 8-197-2 BB-48249 ___ _ .......'2..... ,......... 1*72*. 144........... ............,,V?3 0.0002 B-66-4J IB-47988... . _ 2' ............ .......... G.0032 X*|12 0-M582___________ ____ i_........ .....2.*lla.2.67_____________ 2.69 0.0000 Bt*. Ultramrln* #4S0 0-48249____ ......... 2............ 2.90. 2.82 2.86 0.0032 . fOTULS 16 15*87 0.0477 ,JL i JSe&a for Sample * _. 1|.87______ ** 1*964- ^1.984 * * 0.005962 1.98* S^SSiS' ^.0H23^ Eg Expreeslag the results &e HgO 1$8* k 2.016 - 17.73* BE0 *11.73 - 0.005962 s (1.984)* T17.73 * *17,73 'il0*476l jp.6901 jC HgO DUP050150617 * &LlsSs& fhi rarianoe of th* tua or differsaeo of two *ea.8syerseate ie given toy the equation. Applying this e<partlea ttm xx 1*1 o*47to Froa XX 0, 0,008501 Therefore F^.tS 11,54 " + 0,0025 v*.19 * 4B6 $<1? $| 0.473? * 0,6881 RgO 1: Fro# XX, lif ?j for Total Hydrogen Method # 0*4701 for 8 isgr t of Fm II. X, ?2 for loss Hi Weight Method * 0.02602 for 17 e,r. >f of freedom \C8 degrees of freedom) MmmtL - 9 --" 17,64 Consulting the *sf* tables (Ref# 3) for the 1# probability p5r"b give* a limiting ratio,, ef 4.14 for 8 end 14 degrees of freedom hor.ee w sen conclude that the'.diffarose in observed varieaee Is sigaificient* '!?he loss in Might method is were precise than the total hydrogen method. DUP050150618 -32- MS-1144 J6?-6S* f4-|9 140*156 KB-1166 y ail 36, IfO-lfl MB-U32 P 188 Irfrirter fiMeks tft Kaidta 6/26/45 * ** 12/15/4$ KB-U0 p 140g/X43f P146-14T 88*1144 f 36-3f| 54*56 88*1166 p 6-f, 20-21, |2-?5i 173 88-3144 pg 21-331 52-53, 88-1166 p93| WO 88-1166 p* 31, 38, 172. . NB??ii32 pii? ' ^ IflMtiJtoaate 88-1144 pp 16-25 MB-1166 |f68-6?, 12, 147, W1-W2 MS--1132 pWO MB-1144 pp 6-28, 57-59, 82-85 HB-1166 p36 LaUor Tisdcke to Banks 6/26/45 * * * 12/15/45 HB-1166 pp606l *-1182 p25 H8-U32 PP113-114, 137-188 NB-II82 ppX2-l? 88-1132 p 132 DUP050150619 wnuna (1) Bi IsSuatri dear CyayrMMBg, H Kofcler (2) Baadbusk dor Aaorgaaiaekeo Ghoado ?el* 4 Se. 3* Fart B 2 (1942) (3) fho Amiyaie of Bltt Pimento* F. L# Smamm Falat 16?, 5pt 1?42, (4) FfcygieiLl asi Cfceaieal Saasdsmtioa of Faints, Var&isi.**. Colors, Gardner p. 1002. libth *dltlo& (193?) (5) M8j 4 Paroltlorlc, 8ulfurle and Fbospiseric Aeids end tfeel- applie&iiea la Analysis p* 55* a- C. Fre&ric&Sidth. ChKi<.dL Co* pufeXleatioa,, (6) Analysis of Qfero&e $pee tm& Figneats of Sisdlar Cashes! lion* C.P*i Kappslawier. Rse* Trar* eMa, ?11*18 (1931) (?) Analysis of Cbronete Qreess# C* F A* ISeppelmeier, Verfkroniek. 12W| 35*36 (1934) (8) Analysis of Taarlatioa, X. 0 I. (Pyestoffe) Teobaice.1 R-/ >>>>*, Marefc 16, 19*1. File Mo. I0824 ,_iL DUP050150620 34** wsm I Subject * Iron 11k Figsiet II - Frrooysnid by Carle Sulfate Titration III griaelala The pAgpaat is opened up with dilute eaxeiie md the ferroeyanide produce* titrated with a standard solaticn of eerie sulfate w msmm - J -U44 P, i48-i5i "Cerie Sulfate* Published fey 0 Fredriok 5ad.th Chewier.:. Co. ' Aug. 1935* V Reagents (1) Sodiua Hydroxide eelution <* 20 grama/100 *1 (2) BgtdroohlerAc aeid - se* C.P. & +0.3J (3) Standard eerie sulfate solution +0.1H (4) Arsenous oxide C P. primry standard (5) Iodine sonoebloride solution *g ,,O05M fe prepare dissolve Oa2?9g K and 0.1?% fit in 25* *s& w^ter* lid all at ones 25 *1 cose .* H5 Ms solution eon fee tested for equivalence si fey adding anall mount of MI $ MIVs fuse o-u-?,,**".. the break in the potential Khar, using a calces! * platimm clcetrod system* Such adjusting is uao?. ly net necessary* VI - An electrometer employing a platinum. - c*l*v*l electrode syirten sue as the Fisher iitri.actc.v-. v ii iterates - 2 .5000 g pigawmt into a beaker* lid 10 mi of sodium hydroxide solution (20g/l0G ml). Stir until til? iron blue is ecarpletely destroyed and the precipitate consists only of ferrio hydroadd. Warm gently if necessary to affect decomposition but avoid exce-ssivo heating* Transfer completely to a 250 ml volumetric flask and sssk t the mark. Filter through a dry filter paper (Whataan $41) , discarding the first +10 ad. of filtrate* After somewhat more than 100 ssl have hem filtered, pipette 100 s& of the clear filtrate inur a beaker. Add 15 ml of concentrated hydrochloric acid and titrate immediately with standard eerie sulfai solution using a platinum * calomel electrode eyrfim ti detect tho endpoint. The endpoint till be indicated & sharp rise in the potential. Run in duplicate etartiag with another 25g aagsi Repeat tha dstersdnatlon using a 2*5g as^>l but isafe-e the volume to 500 *1 instead of 250 ml* (Mote) MGTKt This saafeles a correction for the ml are occupied fey tha precipitate* This erre i-. cr is not peat and for wat work, can V neglected. After its magnitude is once established* the dotendnations at dORfelc dilution need not fee repeated, but iho corrections applied to all detersietiftr.. DUP050150621 wn MMH* WSs A aal&i (&04$&required at the 250 aCL dilution* fcet B BlCe (SOeJgreqnirod at the 500 aL dilution A - 2 volume ewer for the 500 si dilution t (A~2B) Volunwl error for the 250 ml dilution Cell this voluas error C. A - 0 Corrected si 0 (804)3 retired for Jggi of the sassyl 250 It say also ho obtained directly fros the fallowing* 4 - A eorr mil Ce (804)3 !LjggJi9AkJ&iaM^ Sample "Wi** in aliquot % F (c% The theoretical amount of Ce (804)3 required to give a 0.1*5 solution is 33*23g/lttr. If the quality of the available C (SO4)3 i-, unknown, a trial portion should he prepared by parting *ershai in es*".-? of 8.3g ia goae cone. HgSG&g diluting with eater, filtering, end sritir-- to a volume of 250 al. This should be roughly standardised by the J outlined below and frea this datum the proper amount' of Co (SO4) 3 is calculated,,, and used to prepare a more nearly C.1H solution. Boss oerio oulfatd purchased from the 0. Fredrick Sssilh Chosdcal Company required 1X0.6g ia 2 liters to produce a 0*1036$ solution* Past the required amount of Ce (SO*)* in $6 ml of cone. E^SO^o Dilute to somewhat less than 2 liters and heat until so sore will g into solution. Filter, preferably through sintered glass, and maks to > liters. X. Accurately weigh < g A&gOs primary standard previously dried at HO -- 120<>C* Dissolve in 10 ml Ea OH (20g/l00El3 plus clout 4C si distilled water* After the AsgOa is collet oly In solution, dilute to 400-500 al and neutralise with *0*111 hydrochloric acid, retag a arrll c\.riy of indicator paper added to the solution. After the solution is rlig-v ly' acid, remove the paper with a stirring rod* Blase both rod ami pc.;.or, and transfer the solution ooapletely to a 1 liter volumetric flash* Dilute to volume. The normality, of the solution till bo O.XQUE, Pipette 50 ml of this solution into a beaker. Add +5*0 ml rattuand 10 al cone. hydrochloric aeid. Add 0*5 ml lodin monochlorlde t-0O;5H) DUP050150622 Beat to $Q% and titrate with the eerie sulfate solution*' The endpoint is detected pottio*eirioaily using a glatimsa - ealosel electrode eyotc.-** A sharp rise is the potential indicate the endpoint. The Co (SO 4)2 neraallty is calculated tern the equation* f c {bo *}* . EdOg^iA&saaa ^celiaSg m Of c* (S045a - 1*851 Soolso^a Farrcyanide Msselve 2s X# (OD)^ 3# {wm) ia 100 isl mter, AM 10 si ceaa, hydrochloric aoM and titrate iMOdiately with the eerie sulfate solution in a Manor similar to that of a ?e (OsJ^ doteradnatlon (g3c BOTEt Fotassiusfwreeysaids trihydrate o&a be considered a primary standard* The crystals should not he unduly c h i ".s . to dry air If they hay a white and powdery appearance f they My haw lost sose of their water of hydration. ;ac\ should act be need* Th water vapor pressure f yflL Hg8C % will prevent the less of water of crystallisation tad th'; crystals of R#e (CH}3%0 say be kept in a desiccatorover 3t# HaSOc* Frs&etieally, simply keeping the CFc crystals in a well stoppered bottle will suffice* The ncriaality is calculated from the equation* DUP050150623 I* MMira - Iren Blue Pigments II -mm Total Kttrogea III* Erlaoirla - The sowwiioaal K^eXtSahl method Is used to eromrt the nitrogen la the sample to esueeie nitrogen end this ej**wir. is distilled into aa excess of standard acid, the remising acid bach titrated with standard alkali* A control is run using reagent grade ssaoniu chloride t evaluate any loos >.? ammonia during the digestion and distillation precoddroc IV. ffiBSS. - . s>2? v. M^aaro 1* Sulfuric &cid * 0* F. Oese* 2. Sapper sulfate - C. F* Oryst. 3 ` Petaseiua Sulfate - C, F. Anhyd. 4* Messy sine or xine shot 5* Paraffin 6. Standard eulfurie acid solution (*0*3$) T* Standard eofdu hydroxide solution { 0.3N) 8. Aassonius chloride - C* F* 0 9* Methyl Bed indicator 0oO2$ solution 10. Sodium hydroxide solution (40g/l00al) vio SM Accurately weigh a 0.5-g* fflsaple and snap in a piece of fil.i*:: paper. A sheet of 12*5 es $40 Vb&tnan is suggested, Place the wrs-pned in an 800-mi Kjeldahl flash* Md 10-graass of potsnsiua sulfater a smll crystal of copper sulfate, end 25-ml# of Cone* H3804* digest r-- a lew flwae turning the flank from time to tine until a straw colored solution results* This usually takes about three hour, Allow the flask te cool but do not let it stand much longer than the time neeeesary to cool it. Add 3S(3ale mater Mid a few pieces of mosey gins? cr sine shot (Mote 1) Carefully aid, dean the side of the flask to &void nJxi--g, 12J>-wl* of concentrated sodimi hydroxide solution* Connect to a Xjeldahl still arranged to rsoeive the distillate into 40-:..'i* -of .'2 sulfuric &eid (*0*3^) containing 3 drops Methyl had indieeter* After it is well-connected, shake the flask to thoroughly sdx* Start the. Slots and distill over about 3/4 ef the eolation* Beck titrate tbo ww* 0* standard acid with a standard solution of eodius 3 yCreuddo (4p*3i1 Run a control in a wanner stellar to a detcjraiu&ii.cn bit instead of a sample use an umst of C, P, aaaoniue chloride d?t< r.t 110$ cossparable to the nitrogen preaeat in the castle (Hoto S). CUcl'rt a factor "X* (see section VII Calculcticr?) DUP0501 3>eteratn* the alkali equivalent and the bleak collectively by naming through the regular procedure hut -without using eaple. Let -the ml. sodium hydroxide required for 40-al, of sulfuri acid under the.'?:. conditions he called ** 1. If the maple coataine e treating agent, it 1 liable to froths during the distillation. XSm&LXy the treating agent ie destroyed daring the digesting of the wrapl but eeeaslonally enough rMaine to sake trouble* Ala the eeople *eaatie froth mm without a treating gent* A snail amount of paraffin added at this point will help cut dssa frothing, that is mm more effective is an infra-red Xess> held close to the neck of the flash. A oil of wire 00 fashioned as tc spire' up inside the neck of the flash "also tide in broakius the bubbles as tbs? rise* 2. f&e control should give very nearly theoretical retmlts sc ao great error is introduced if the amount of axnoaiun chloride used deviates fr* the equivalent in the sample. It is roeoasamded that if there is interest in both oanenia nitrogen and total nitrogen* the amount of tUKKoaitm chloride used in the control ooaa midway between that ettgt7<:sr3vy found in an mmxmXxm nitrogen and a total nitrogen. Using a 0.5-g* wsj-.e for total nitrogen* and a 2-g. eawple for aimonio nitrogen, and aesuaiMSi 29?e b as typical for total,nitrogen and $ H as typical for awionia nitrogen, an amount of emtoniun chloride suitable for a control ie 0d5~' * HHepl* III. OAlgUMTlOHS A. Oaleulattm-Of-Asat^^ K ___ HttML*OMaJitti______________________ _____ ____ (K-al* HaGH for back titration) x Boraality of RaOH x 0.0535 The value of *K* should not be ouch greater than lc003 X m a&,, of Nb0B required to neutralise 40-1. of standard BaSO# while sashing a blank determination as outlined in the last paragraph of the procedure. mQU M^ mmMd)..x.QQU.x K a. 3.00. ; BaifAe Weight .. C. Calculation of (OK) nitrogen ms Fe (Oh)4 ic.il nitrogen (This calculation presupposes data for awaciaia nitrogen) Xfeii.JMaJISL.MlfeLMtefssiX.* % adiiiequf vt~ Sample for 'total ultragm lece of tot? Bitroger. JV, DUP050150625 _ ____ Saapl* *lght for tu**oia aitregeo U~B> * 0,03533 # <cFr % js&lXlo^uimXe/.Ms of omemife alti'Ggefi DUP050150626 mmmjk X* l * Xvm Blue figment xx - Jbwsoala Mitregen XXX* IffiSiai Xhe conventional lyeMahl till i* used to distill the WJ5sis>i ft1** a mad alkaline, into sa *; r? standard asid and back titrating the excess Tilth standard alkali* 4k eerresilen Is applied for the small awuwt of s-. ,r.e .; i produced by the slight de%sitis of th* fsrrocysnidt* * " * * #2X66* p* 36 * * #1132 p. 138* 1* Sulfuric add 0 F* Cm. 2* Sediuni hydroxide solution (40-*g/X0CHal} 3* Messy sin* or sloe shot* 4* Paraffin 5 Standard salfurlo aeid solution (jtP3H) 6* * sodium hydroxide * * f * dBeiu eUeri&a 0* ? Sraa* 6* Set&yl Red indicate* tift wsaam Aeeurately weigh a 2-graja suable into as SOO-3&* Kjeldahl flask* 4dd 3GQ**!* of aster* Add 5~al Gone* IlgSO*. and mix thoroughly > Add a ftm pieces of mossy sins or sine shot and carefully add, down the side of the flask to avoid sdjdag, 125*1 0# concentrated sodlwsi hydroxide solution (Mote 1) Oonneot to a lyeldahl still arranged m receive the distillate late 4Q*b1 of standard sulfuric acid (40*3?) containing 3 drops of Methyl Bed indicator* After it is v#lloQne*':iec ? shake the flask to thoroughly mix* Start the dietillation m& distill ever about 3/4 of the solution* .Sack titrate the excess standard acid with standard sodium hydroxide solution C*0*3M) Bun a control in & Banner similar to a determination hut instead of a sample uee an amount of C* P ammonium chloride dried at X10y ocasp&rable to the nitrogen present in the sastole (Mot 2) * Caleulate a factor, "X" (see seetloa TO Calculations)* Betermiss the alkali equivalent of the acid, the blank, and the ammonia formed because of the cteoenpositlcn of the ferroeysnid (Koto 3) by running a typical iron blue pigment for oanujnia nitrogen, filling tfeo distillation flask back to the original mark with distilled water, or.d redistilling into another position of standard acid* Repeat ftes procure three more times and average the last three results* let this <jfuatity be sailed "1* and use it in the calculations as indicated in section VII:. DUP050150627 1* If th* MRlo cestains a treating agent* it ie liable to froth, during the distillation. k email amount of paraffin added at tfckpoint sill help eat leva frothing* What is ms more effective ie & infwwred leap held decs to the neat, of the fleet. A soil of .sir-j ss fashioned as to spiral up inside the m&k of the flash also aide Ui breaking the bubble* as thag? rise. 2 The control should give eery nearly theoretical results sdtethsr ran as a total nitrogen method or an ammonium nitrogen, method. If there in interest'in both. It ie permissabla to run am control for both mad see an amount of ammonias chloride aidwiy from that shleh wtmM b# found an mswoaia nitrogen and total nitrogen. Using p 0.5**g *cuqplc for total nitrogen* and a 2-g. sample for enmoaia nitrogen* sod aseuaduf K ae typical for total nitrogen and 4$ M as typical for amaaai& nitrogen* and amount of amcaiwsa chloride suitable for a control is 3* Prolonged alkali distillation of a ferroeyanide asm produce costs nwBoaia by deoesaposltion of the ferrocyanid* This amounts to *be*r; 0.22 ml of 0.335* HaOSI. Ibis is quit constant and after it is sme established* it oan be considered the asm for all samples and all detersdn&tieas Its ocnetaaey and amount are illustrated by the follows., ig dates OiatilliHg Fe (e#JTfreo ml SaOH back titrated from 40 ml standard acid 1st distillation 2nd 3rd 4ih t* m vt 5th 6th ft ?th 8th 9th Are. * 30.95 30.90 . 30.88 30.83 30.91 30*90 30.80 --30j*80_ 30.88 ml h&OH hack Titrated from 40 ad Stand. 31.10 31*10 31.11 31.10 31.10 31.11 , '31.16 31.10 ml 30.88 ml 22 m Of 0*3353* KeQH DUP050150628 42~ *ie* JM^M,mminrn&. |iKSt iS. for feaek titraii<m\x Mwmliiy ef ifa,01 * o \ of control / Sw& of Jtefl r<jira to swotralis* 4CH3. of at&ud&i*! KgSO* ofelle mklog a blssuak toterattmtlm* . * Oolilo*lfltt. ofcnjW*U pftfffyfifM . .g>SftP,QUB4. *fcax 8tO$3. tJw DUP050150629  4* mmmM h'll^ * Blue Pigmste II mimmsAnos Total Xrea* XU* HtllSIPM * "Stos rapid is" Opened up 'fey gentle ignition and treatSt with hydrochloric raid rad perchloric aoid* The ferric iron is fhm tttrated with a standard solution of tiianaus chloride* in mmmucE s, r * #n66 pj>* 6, 20 mm 1* Hydrochloric acid - C# P* Cone* 2* Perchloric Add - C. P* 7# 3. Bt^croxol (30J* H0g) 4* Potassium permu^prakte JD.UJ 5* Utanoua chloride - Standard scluiicii *0.1N S9 Potassium thiocyanate solution (l5-g/l00-l) ! Staroh - poi&aeiusi lodid paper. 8. Titration mixture* Dissolve 90* ifetSGe.HaO in S50 1 waierj heat if necessary* Mi 175 ad eano. BsPOa and 175 ml cone* HaSO,* Dilute to 1 liter* mmwm Accurately weigh 0*4000-$. sraple into a flash (500-?l. suggested sl*). Ignite over a free flame rolling the suable around ia the flask during the ignition process* After most of the ea-apis i decomposed (Note 1), add 10-sal. Gene. BCl and 25-al IB10** Place a trap on the flask to prevent excessive loss of required for 3020* fuses (Nete 2). Use goggles* Continue the heating Wail the solution acquires a cl|r orange color* Allow the solution to cool and add 200-al. water. Reserve trap sad heat to "boiling until all of the free chlorine ie feolled off as indicated fey a negative test with starch-potassium iodide paper* Add 0*5-al* superoxol to rdti=e chromium if any* loll until the volume is +100*-xl, to destroy the excess superxol* Add 5~1* titration mixture end a drop of potassium permanganate solution. If the permanganate is reduced, add more until a faint pink color persists* It should not take mere than 3 OP 4 drops* Add a drop of titanone chloride solution t discharge the permanganate color. Bo not count this drop in the tltanoua chloride titration* Add water to a volume of 20O-ml Add 40-m1* of Gone* HG1 and titrate slowly with standard titanone chloride solution (eO*2N) Near the end-point, add *10m1* of SCN8 solution and slowly continue the titration to the disappearance of the red complex thiocyanate color (Not J} wms 1* It is not necessary to decompose ell of the blue because DUP050150630 ike imtbsequojai treatment with HC10& sill complete the destruction,, 2, Feroblorie asl* is safe when proparly wet but to randy.; a#, its dangers sites enreXtBily hand* goggles ahould be trorn at all ti.:.^ when narking with this mterial* & trap of sea sort- is aeosasary because HC10& tm tend it. oarry off mm of i>M constituents of the sample* Also t&@ loss of lrai| because of th relatiUty of farrle chlaride, is prs-roatst* 'ft trap Hast ha all glues* ho robber or oork connections are persdsasbl because of tha explosive mture of perchloric acid when brought late contact under certain conditions with organic s%teriais A distilling head -with a 24/40 standard taper in Aonneeliea utth a 24/40 standard taper flat bottom, boiling flask sake a mtlsfa s.tory eoffibimtion. 3o ft titration should bo carried out slowly because the reaction is sluggish* fid. la particularly true near the endpoint* fits presence of the phosphate fro th titration mixture further taisis to inhibit the reaction* It is good technique to aid more potassium thiocyanate shea at the endpoint. If a slight reddening of the solution occurs, th* endpoint was not quite reached* If.no reddening occurs* aid a drop of ferric iron of about the same normality as th titanus chloride, Thor should now b a reddening of the solution^ If none occurs* the endpoint was passed and the proper correction should bo applied as indicated by the snail back titration with the ferric, iron v m* CAMUMTXOM Sample oi^st F DUP050150631 4fTM I* II. III* mail ffOBOBCY - Iroa Hue Pifsaents mR3lXNmOH Total Alkali Metals fRMSUPUl " The cample is decomposed by gentle Ignition .fell yjv by treatment with Bromine water md The .fesEry **! w removed with MMuas hydrosid# and the alke.li. *tale veiled as sulfate. B. #1188 P. 93. i Broadne &* Baporoxoi * "^0% HgOg 3. Asooalia* hydroxide - S? Concentrated 4. Ammonium ehloride 1% Bol'a. 5* Hydrochloric &it - CP Cone. 6 Hitric Add * OP Cone. 1. Sulfuric acid ** OP Cone. 8. Jusaowium carbonate ~ CP. VI. FROOBDlffiE Aeeuratsly weigh I-grss into a percelsda evaporating (3-3/^w dia. suggested). Saatljr igrfta over a free flame unfal*'. all .c' the blue has been ndditd> and the residue has a brown iron Dxvlr. oor.or. Avoid igniting mch beyond this stage* Add 15-ml* sene. H51 and sar.-s on a steam bath. Add eauticuely a few drops f farnine and ontirco 1 for a few Minutes, Placer a ribbed watch glass ewer the dish* Cuvtl fu*'.;/ add a few drops of wpirt to the dish maintaining -the watch "lass -'n such a position as to prevent lose by spattering, and continue her.tiij.'-; until the soltuion is evaporated to a low volume. 'Wash down the side# of the dish with distilled water as necessary during these operation Transfer to a healer and dilute to J*200l Beat i boiling end boil 10 minutes* Add Cone# Aasonium Hydroxide dropvige, with stirring, until all of the Iron is precipitated and the pH is *7. Boil the solution w.i..u\ the precipitated is well coagulated Cjl Mb.}* Filter through a #41 Whatman paper or its equivalent and wash with hot 3$ HK-jpl solution. Dissolve the ferric hytrorf.de precipitate in about 100-ml. of hydrochloric acid and reprecipitate with araaoniua hydroxide a befcrv. Filter and combine filtrates. Evaporate to a low volume m& cautiously add eQ~al* of Cone. $H0$ After the volution of orfdes of nitrogen hr r. subsided, continue the evaporation* Aftdauother*^-i portion of 0..iot HROs and treat as before washing down the sides of the builvr os nt>eese?u`. * Treat with a third yj>0-l, portion of Cone. HHCs. By aov :ta,t ell of t.:v. ometdvm salts should have been removed and the addition of HHOg should not give rise to further liberation of oxides of nitrogen. However, if -V a reaction is each as to suggest sore mmmlm salts, continue the trrr` meats with HHOe, washing down the sides of the beaker until the furtHr DUP050150632 addition of Im causes M liberation ol oxides of nitrogen, ;* >ert.i 46 m 1m velum and sM Qom, BOX, Again evaporate 4c- - W w Is bms sea add & second e$D*tL* portion of Oeae, Wl and swporat* to a low mOum, 144 a thl*d. tertian of Om, BC1 which, fey now, should act give rise to the liberation of oxides of nitrogen, the aitraise feeing oKVrteA to chlorides, If oxides of nitrogen are produce^, continue the addition of Seas* BBX, malting down the sides of the feanl- f ttatil o todies of nitrogen ere liberated, Bveparat* alsost to dryness (avoid guttering) end transfer to a silica dish fey repeated washings with water, & silica diea 4 l/2* die, * reeowwnded* #44 * drops Cone* HgSOg, Plato# a ribbed watch glass over tbs dish and. evaporated o a rfceaa bath to as low a volas* se possible, Rssove to- * hoi plate and gradually iscreas# the tenperature, Finally,, ignite over a free flume playing tbs flasse over the satire diafe until 80s tvma m longer ere liberated, (Hot l), Leach with hat water .sad flit? through mall #45 Ih&taaa pqper or it B<juimlat into a tar# Him dieh, lash residue thoroughly with hot mier. Add & drop# Qoae, BgSGd to- the filtrate In the dish m& repeat the evaporation and ignition* MA a snail wmmt of mild aawsraiusa carbonate to the residue in the dish and heat mill the wmmltm carbonate disappears Repeat this procedure about three tines. This destroys any pyrosulf *- s that nay have ferasd, Seel In a deg&eeator and weigh m alkali ?-wtel sulfates {Sots 2), the identity of the alkali net&l can be setablic i :4 fey the oenveaticasl flmm test* nonss 1. This ignition converts the remising Iron to the xiuc *sk:-.r, it insoluble and filterable and eliwlnatoa the need for Hg$, Fc.r the raaoval of certain ratals, it nay be necessary to saturate the solution at this point with Bg# and add a little assaoalu* carbonate before filtering. If this procedure is necessary, the addition oi *1G~h 1. of 0,02? solution of low aah gelatin will aid in the soejgaietim of the sulfide, 2, The residue will **ually contain a trace of iron which msj bt neglected. If the aaeunt is thought to be excessive, the residue should again be leeched with hot water and the filtration and ignitico processes repeated* X IQO x 0.4364 * Sample weight 'M&M.M.JM.Mm. x 100 X 0,540b * ?%Q Saagple weight 0 DUP050150633 I II* III* SUBSIST - Iron Bias Pigments wsmmmm - *i gRtMlflJL, Tb ires, Bias Is destroyed by gcrito *gmu>i:e fellosed fey treatment wfcih hydroefcloria aria add* fh ohroada is oxidised during the j-crchles is a treatment and It is determined fey adding nr cf r standard solution of Mohr's Salt* and back tinratii'i: `X a standard solution of permanganate. If* wmmm *. * fuw . 31* 38 - #ut 7* 'timzLxm 1* Hydrochloric acid * CF ooac* 2* Perchloric sold - CP |0-?2$* 3* Staadard solution of Mohr's Salt (*0,18) 4* Standard solution of Potaoeim ;e 4 (0.1M) | titration sister. 6. Starch ** potassium iodide paper* . QfiBBSBi Accurately weigh *grsa sag>le into a flack (5'00 ,1 suggested sisa) (Jlote !) Ignite over a free flame rolling- the :,.*<' around in the flask during the ignition proses#* After most of 'r:* sample is decomposed (Mete )* add 5*1 Cone. 801 dons the si do -f the flask washing down any .pigment adhering to the nider* "'irrw-'Vto nearly to dryness hut neld spattering* Add 15-ial HBlO*. dots a trap to the flask to prevent excessive loss of B510* fume and ' >. - at a to|>4arattre somewhat in utws of that required for HClOa - ' * See goggle* (Mote 3) Qtmtinue the heating until the solution -not.a clear orange color* Remove Cron the toum of heat sued allow o eool slightly (+10 sec) cautiously add a little eold tw through the trap and then plunge the flask into is water* Withdraw isanediet and again plunge into the lee water while osirliag the contents of the flash* Add 0"1 cold water (Hots 4)* Remove the flask frou thiiee water hath and wipe dry* add 140a water* Remove the trap sad heat to boiling until all of the free chlorine is boiled off &s indicated fey a negative test ea starch * potassium. io<:dc\. *,s,pc, * Cco.'. ami add 10-sal titration mixture* Add an excess of et --t k>Xf' salt solution (ICHal suggested) and titrate the excess .it* c6tr;.E-xi pemwo^iaage to the first color change* (Rote 5)* mm 1* XU* amount of sfaroadtu has feeen known to widely vr-ry. The 2-graaj sanple weight suggested- assumes eremad O.# Or* For ' -.sr./ amounts of cferSKtafcy the sasple weight eon fee cut dew feet 1-* :.*r o,' n not fee more than 2~grtaM because it is sore difficult to apt iv. ** Mnplg and the high concentration of ferric iron makes tha tatrs^ioa more difficult* 48" It in set necessary to deoenpoee all of the blue* in feet, it la quit* difficult to to o because of an ineuffieient smyjJ..;, of oxygen istiii the flask* the snail assount of blue tmedxdng rvX ' bo ecag&etely destroyed by the perchloric aeid* 3 Perchloric mail is safe shea properly used but to 1b 1~ aiM lt dangers when carelessly used, goggles should be warn at all tines dba working with tide mterial* & trap of seen sort le nmmmry because HDXOo fasts a t 3 4 to carry off seen Of the chronica* The trap east bo ell glass Ko robber or eerie eeaneetlens ore pwraisaeble shea using perchloric aola because of it# explosive nature when brought into contact under 3artel cca&itiens with organic mtoriels 4* fte sedation oust bo cooled rapidly because it has been observed that the redaction product or deeespoeliion prefects of poreblerie acid any reduce sea of the chroalua. If the solution is rapidly coded, this occurs to & negligible extent* . $ For larger amounts of ofcrcB&ua, it nay be necessary te add acre than lHtiU Of Mohr's salt* Aa exeeee is indicated shea ih* eolotioc hate a clear* greenish color* Th adpoint Is rather indisticof because of the high concentration of ferric iron* With a little experience* tfcsiois m trouble* 11* QAt/mTA* Cal !&$?** ealt * Sorsnllty of Mohr* s ealt)l DM)* x jtaamijsyL^^_____^ Scnpie Weight DUP050150635 X# XI* XXX# HH &mmjt Iron Slue Mgseats HU - *o*al Sulfates PRI1381Fil Tli ivm blue pigment is decomposed by boiling -: . sodium earboaate solution* The iroa oyenide eoapir-r i converted to tit mercury cyanide complex with freshly cipitated 8g0 Sulfate is determined o the acilifi ed filtrate by precipitation and weighing m barium mi2i *;; XV# STATOS This method has been used BUceeeefully on quite a nu^er- f,l' iron bio sample.. She sulfate recovery stow aulfote has been ukh-.d l; a easftle has boon good* v. Bromgai * x, b . #n6b ?*92, 14? VI* SSMMS * 1* Sodium carbonate - G,, P Cryst. 2# " * 10^ solution 3* Bydrochlorio acid ** Cons* C p, 4# fellow mercuric aide - C# P* 5* Jhaaoitius chloride - C, P* Cryat* 60 Aimondum Hydroid.de - C P * Cone# ?* Barium chloride * 20yC Ba CXg #2 EgO vii* ffigiH, Accurately weigh a 1-gram sample into & 400-1 beaker.. ::ci of 10 NagCOs solution and boil for at least 5 minutes,, P* cy. r' gem freshly precipitated mercuric oxide by dissolving 3-grams o:f.' ?. ? , yellow mercuric oj&de in & small amount at hydrochloric acid -ami than rprecipitating the oxide by adding first solid sodium carbonate and, _?. preeipitation starts# add a 10j solution of sodium carbonate until the Mature reacts baeic to iadieator paper* Add this mercuric oridu slurry to the decomposed iron blue scurry and. boil for 1$ minutes, wasiring tor. the sides of the beaker m necessary* To tost for the complete deetructi > > of the ferrocyanid, take out a small portion of the slurry (*>ol; /.si* aoidefy it with hydrochloric acid* bet stand a few minutee, So hlu*. color should appear* Add sodium carbonate solution to trie test :a until it is again alkaline and return to the bulb of the lorry* Go; v:. ?**. aosordiag to one of tfe two following alternate procedures, At ps/diu* alternate procedure No, .2 is thought to be less troublesome (Bote I'.); A DUP050150636 Alternate.. PrtMdmJfai-.lt. If no blu color appeared# add XCCh h I. of* bromine iiakr and boil ike solution* foot for acidity and if acid, wore sodium carbonate solution* filter through & #40 ?hats.n paper or its e..;.>tvr...\ at ad wash with & hot 2$. solution of araasoaiu ehlorid. If eotae Of * J,(i preeipltat* appear to ran through os* if a slight precipitate f;-r;s i:. the filtrate# it may bo Add hydrochloric aeid to the- filtr- te (Caution - ee & hood because hydrocyanic sold is liberated) until th? MtaUflD tests strongly acid and start bailing to a low volume, lias a. vs. the precipitate la L00ed. of JJJt (1*3) and regsredpitat with si'Aua carbonate adding it first a a solid and when near the neutral pnlrt, -' M it as & 10j( eolation* Add enough to stake tfe solution. distinctly hsut to boiling# boil for a few admit* sM filter through a What --a. 'i.") or its equivalent* Wash the precipitate with a lrw "i$ NHspl 8c2.uti.ee, Acidify tka filtrate with hydrochloric ooM and combine vitb the first filtrate. : ^lft)^aatogr&ad8reic,2 If no blue color appeared* add 5*s& of ammonium hydros!d, b:,'l a fear minutes longer and filter through a #40 Whatman paper or Aitequivalent* Wash the precipitate with a room temperature 2# solution - f ammmlvtw chloride. A slight turbidity, is the filtrate nay be nagicct ; ', Add hydroehlorlo acid to the filtrate (Caution - use & hood beers,-* hydrocyanic acid is liberated) until the solution teste strongly acid, ai-.r. start boiling to a la volume. Dissolve the precipitate in *iOGkj I, * t-4l hydrochloric ncid (1*3). A certain amount of the precipitate wH? remain as a shite residue. This need not be dissolved* y.eprecipi trie ,.ith sodium carbonate adding it first as & solid end shea near the noutral r cl-'** add it as a 20j( solution* Add enough to rvXe th solution distinctly a sic# and boil for a few admitos* Add 5-ail of err oaf. ri %$?*:&&* and sg-ai'- loti for a few minutes* Filter through a Wfcataua ,?40 csocr and wash with ; l iaoniu chloride solution at rows tessperaturc* Seglset any rli-pi precipitate ia the filtrate* Acidify the filtrate with hydrochloric u--J4 and combine with th first filtrate* Svaporate the combined filtrates to a low volume (until cryst-pJ.e) appear or until the volume is about lOO-ial,)* Test th acidity durir.{- ths evaporation process and if the solution bag turned neutral, add isore hydrochloric acid* This evaporation insures the removal o.C all. of the Fv? Make the volume to 400-!# Add ammonium hydroxide until the ap ears.?-' e> of a precipitate. Add d-ai* Cone* HC1# heat to boiling and adi, drop rise with stirring# KHd* of 20$ barium chloride solution* Heat for l/2~: and lot stand oversight* Filter through a weighed Gooch crucible cc. - -J.xing an asbestoes rant and an ashlesc filter paper dish (Whatman vH0 or. ecv>l-/alentj (bote 2) * Wash with hot voter, ignite# cool and weigh as Ba 504) ,, DUP050150637 1, Kithsr alternate groesdtire tends to give a cloudy tv.tret ? and the separation f the sereury is iaeoayplofc hot the aBount remia* MM to So hot little tarsi. Alternate He 2 restores more of the sners-.ry giving; a lesser separation and it is for this reason that, it is thou? t to bs lose iroublsaew* 2 fho filter payer dish is optional. If may sulfate detenEi>..atlons are mads? it is eowrenisat to use a paper disk hi oh permits the reacv.rl yJ tfa* bulk of the BaSO ash by oiaply biosing it out or brushing it mst 'Ku mm asbestoes *s$ my then be used assay time* nn Q&wmAfimm 4gb*, S08 I; DUP050150638 APfSHPIX a i* mBmnt ~ iwm Bie pigment s. II. Ill 1?. KSUlffiil - fatal aelstnre by lose in weight. YBXWIFZM The doable is dried at a constant temperature of 160*0* Cosapeasaiioa is made fey loss i weight due to it-i 'mpmi-* iisaa of the felue fey an axtra.pclatJ.oa teohni^e* BETORESCB - X, B. #1166 P, 36* v. SiakIM@..................... Brafeeader ass&aiure tester* file Is simply an oven with u feal&soe so attached 'that the aasgtle can fee weighed without removing it f:rm the even* The vf*dgjfet scale reads directly, fless In weight. l 5v ! The method is admittedly aspirieai, It has been applies, to a large number of ires blue pigments with results that are believed is b sparable* ?ll. ngsie Weigh a li>gram sanple of pigment on the properly tp.red aluminum pan provided with the Brabender teeter. Place in the Ircbtu. .:>* wea which toe been preheated to 160^0. Detailed directions for the ?vjn of the iastruncut are supplied fey the wsmfacturer end should fee <-cDi:>:-.ic4o During the tiro of heating, no sample should fee loft in the space immediately in front of the van door because experience has shot iro: the temperature is a little lower in this position. The position of v j angles in the von should not fee changed except a is necessary whr, weighing the samples. After the sanplec are weighed, they should fee returned > s their original positions* This will minimise the effect of a tempera: tro variation in the van. The oven door should never be opened during t' course of a detwMaatioa and the oven should be kept away frost draf-;- 1 Readings are taken every hour for the first 5 or 6 hours. HM data are plotted on rectilinear cross section paper > plotting time a afesiesa and percent loss in weight as ordinate. It . fee observed that after the first or second hour, the curve will '>0 essentially a straight line and will fee almost parallel with the absirn. $Hote 1}* Laying a straight edge along the linear portion c-f the o.- m, draw a line which will intersect the ordinate. The percent lose i>i * as indicated fey the intersection of this line is taken as the per am. moisture in the blue (Note 2} DUP050150639 Is There will fee & constant loes in weight due to the ddoosspoeitioo of the blue, fhts will give the linear portion of *be eunr a slight elope* ffe mapdtiaie of this slop will depend on tfee nature of the blue, feeing quite large for toning blues such, e.e > 2* fids extrapolation to aero tins dialBates the decQ^.or:,-.. >n effect of the blue* It hag feeea observed that the loss ia weights elt.-jr drying for ea# hour, ia reasonably oloee to this rirepclated hea for rontiao analyses* it aay suffice to use the percent loss ir. wight after one.how? at lio^B* & the pereeat moisture in the ttzvzl",- j DUP050150640 I. n. 111, If. -** ammoLi. ~ Ire B} IffMTlOSg Iren outside of the Iren Bin# molecule. wnDlMB - 4 easels it shakes with 20J4 by yolws'.s hydrochloric mK and the iron is aolatloa is titrated with & standard solution Of Ti Cltm M8W * X* 8* #1166 p,, 60-6lj X B #1132 p. l3f SairW Cone* HC1) (l) hydrochloric Iid ** %ff* fcy volas* (8QisX HgO + 20 r 4 (*) Potassium ffcioeyamte solution - (1? f/lOO ml) (3) Titsaow* obloridi standard solution *pH i& mm&mm Weigh & 5 gran sample isle a 125 && glass stoppered Fipetts 100 JSI of 21$ by wolum hydrochloric acid. $hake overnight (^6 hrs.) is as aatojaatle gheJ&ag device* Let stand until sow swfctli *g has taken pines (*2 fare*}* Dscant Into a 300 ml centrifuge tubs, the tabs and centrifuge until the superaatoat liquid Is clear {45 &: ,)<, Filter through- a dry #3 Whataan filter paper or its equivalent, iiocn* ling the first *15 ml* of filtrate* Filter smmgmt in excess of $0 ml,, Pipettte 50 ml of the filtrate into a small flash* Add 5 ml of the SCI solution and titrate slowly with +0.1X Ti Cla salutian to the disappearance of the red ferric thiocyanate complex* vn. Sample Weight in aliquot DU P050150641 -5* AFPKK01& la X. SBBJEGY Iren Blue Pigments IX. SBSSSIgmflOB * Organic Treating Agasi, XII ERXMCIPig. - Hue treating agent is extracted in & Soxhlet xtncter using ft Jp ter veluss# solution of acetic maid in chloroform, XV. RgmatCB - X. B. #UB2 p. 12-1? H. B. #1X32 p, 132 v. MAtmra (X) Acetic Acid * fflccial C. P. (2) Chloroform w. Mi - Accurately weigh three grass of pigment iM wap in a piece of ^40 Whatman filter paper or lie equivalent. flees in an extraction thimble and extract in a Soxblet extrator for 24 fare. If the eolation contains pigment particles or filter paper fibers et: ishould bo filtered, Otherw&oe transfer to a beaker and evaporate to a low volum on a rteea bath.. Transfer to a weighed evaporating dish and evaporate to dryneets .Avoid excessive heating because some tr-suti:.; agents have rather high vapor pressures. Place in a vacuum desiccator am sulfuric acid and dry to constant weight. This will usually tahr no longer than three days. MOTS Boats samples bleed <gulte badly hecsiice of the mature of the treating agent. The effect of this bleed can be minimi zed by evu> orating ost of the chloroform and substituting diethyl ether. This often time flocculates the iron blue and it may now be filtered. It filtration is still difficult the ether suspension may be centrifuged and the practically clear superoatent liquid filtered through a i'$ bhebrnsn filter paper or its equivalent. The email amount of pigment separate.', in this manner will contain measurable amounts of treating agent - I:' greater accuracy is required, this pigsent should be re^ertractec in a manner similar to the first extraction. VII. fhUSIIUTXOIIS It..of JWdrhelLX..1QP * % Organic Treating Agent, Sample Weight DUP050150642