Document B8RjbR1m97oa2mmX1o0ENpBxw

Dr * I. Gubelmann~1 Dr . H. A. Lubs _J Dr , E, K. Bolton Dr * William Kirk Mr . J. S. Groves for I.C.Ij J. 'h. Piles B. X, DuPont de Nemours & Company Jackson laboratory June 10 1942 Thiaatral Green 2G Development of Processes for Tetra Witro CPC of High Quality __________ . N40780 JLR-52-X08, Wo . 3 Serial Number 17964 Prel.S.W. Process 17964-A & B Tent.S.W.Process 17964-A E, I. DuPont de Nemours & Company Jackson laboratory Miscellaneous Dyes Division 0. Slallmann Progress Report Jwaa. 10* .1942 Thlastral Green 2G Development of Processes for Tetra Nltro CPC _____of High Quality Group Leader - 3. R. Detrick Work Started - December 16, 1941 Work Done By - G. B. Robbins Completed - June 10, 1942 Reported By - G. B* Robbins J, M. `PINKER ASSISTANT DIRECTOR W. 3. CALCOTT DIRECTOR DUP050059010 Thiastral Green 2G Development of Processes for Tetra Nltro CPC of High Quality __________ (Project #2149)__________ ,, G. B. Robbins JLR-52-108, Wo. 5 Serial Number 17964 Object of the Investigation? To develop processes on a Semi-Works scale for the manu facture of Tetra Nltro CPC for subsequent use In Thiastral Green 2G. Period Covered by the Report: December 16, 1941, to June 10, 1942 Historical Background: Following reports from X.C.I. on copper tetra-mercaptophthaloeyanine, work was begun on this subject and led to a decision to prepare a final sample of this product (G. B. Robbins, JXR-59-1-M, No. 6} Serial Number 17226). Work was continued under Project J-52-108. After evalua tions and cost estimates of three alternative routes to give products of this type, i.e., copper tetra-mercapto-phthalocyanine, copper tetra-thiocyano-phthalocyanine, copper chloro-mercapto-phthalocyanine, copper tetra- thiocyano-phthalocyanine was selected for further development (G. B. Robbins, JIR-52-108, No. 1; Serial Number 17355). Production in the Serai-Works of a trial lot of this product, known under the name Thiastral Green 2G, was authorized. After preparation of a pilot charge of color, which was very dull, a re-examination of the processes was undertaken, and it was decided that a more fundamental study of the processes for Tetra Nltro CPO would be undertaken (G. B. Robbins, JLR-52-108, No. 2; Serial Number 17465). The work described in this report covers the investigation which led to the preparation of Tetra Nltro CPC of superior quality and the development of processes for its pro duction. -1- DUP050059011 Conclusions: Processes have been developed on a Semi-Works scale which gave Tetra litre CPC of good quality .as indicated by analysis and laboratory controls oh conversion to color. A supply of Tetra Nltro CPC $J*0 lbs.) of over 95/6 purity has been prepared in order to produce the trial lot of Thiastral Ch?een 20. Summary: The subject matter of the experimental section in this report- tees been presented according to the following outline and will be discussed in this section under that outline: 1. Preliminary experiments on Tetra Nltro CPC Tetra Nltro CPC has been prepared by heating a suspension of 4-nitro-phtbaliraide, urea, cupric chloride, boric acid, and ammonium molybdate to 150-155C. in an inert organic liquid. Following the outline of the procedure in an I.C.I. Report (H-6004) substitutes for the chloro-naphthalene Used therein as the reaction flux were investigated. In addition, the temperature of the reaction was studied. On the basis of physical conditions of the crude pigment, the purity of the product, and the ease of removal of the liquid, the use of ortho-dichloro benzene (ODCB) at 150-155*0. was chosen for further study. 2. Consistency Series on Tetra Nltro CPC In order to verify the consistency of the reaction condi tions which had been chosen for further study, a series of six runs were made, purified, reduced and converted to color. The agreement of the runs with each other was entirely within the range of experimental and analytical errors. The quality of this material was determined by analysis of the material, by analysis of the Tetra Amino CPC and Thiastral Green 20 which could be prepared from it, as well as by dyetest of the final color. --2-- DUP050059012 3. Effect of Varying Conditions on the Urea ODCB Fusion of Tetra Nitro CPC A number of variables were tested in order that possible improvements might be effected and the critical points in the process be determined. It was found that portion-wise addition of urea at 135-140*, which might be necessary to prevent foaming on the large scale operation, could be carried out if necessary. Extended heating periods (12 hours Instead of 3 hours) and increased usage of ODCB, showed no Increase in yield* Use of smaller amounts of urea gave lower yields, and decreased amounts of ODCB gave a very caked and lumpy product though its purity was satisfactory* Use of less cupric chloride and catalyst was adopted since it gave satisfactory results* It was determined that ODCB could be used in the slightly moist condition in which it would be obtained by merely separating the distillate from the steam distillation, 4. Acid Pasting of Tetra Nitro CPC A series of acid pastings was run in ten parts, of 98# sulfuric acid at 0-10C. with varying times of exposure to the acid after the color was in solution. Wo instability was noted, even after 24 hours exposure under the above conditions. It was further noted that a temperature of 25-30#C, for a period of 20 hours in sulfuric acid solution had no injurious effect on the product. Accordingly, Tetra Wltro CPC can be considered as stable and easily acid pasted under usual conditions for that operation. 5. Purification of Tetra Wltro OPC Since it had been determined in the preceding sections that material of good quality could be made and that the material could be acid pasted satisfactorily, a simple method of purifi cation was desired, bearing in mind that acid pasted material had given slightly superior quality in previous experiments. (JIB-52-108, Wo. 2; Serial Wumber 17463, Table IV.) (a) Purification of the urea ODCB fusion by filtration, and drying of the press cake followed by acid pasting, was studied. Decomposition of the urea-degradation products, possibly in con junction with unreacted 4-nitro-phthalimide, occurred during drying to give material which was difficult to grind and contributed a dullness to the final color. Shis decomposition Is considered one of the most serious difficulties in the original process which involved drying of a cake wet with Deo Base. DUP050059013 Furthermore, the crude which was obtained by direct drying of the cake, contained only 42# Tetra Nitro CPC, but required ten parts sulfuric acid per part of crude to acid paste it, This is equal to 24 parts sulfuric acid per part of Tetra Nitro CPC, Such a low efficiency of acid pasting is uneconomic. This feature, coupled with the poorer quality of the product, eliminated this method of purification of the reaction mixture (b) Removal of the ODCB by steam distillation under either add or alkaline conditions was found successful, giving a simultaneous extraction of the urea-degradation products. Crudes from alkaline distillation were about 90# pure due to precipitation of copper oxide and certain acid-soluble inpurities, while acid distillation gave crudes of 95# purity. Either type of material was found to yield good product on acid pasting. Corrosion occurred due to presence of copper ion which reacted on steel test pieces. However, the corrosion rate in alkaline medium was ,0025 inches per month on cost steel and this is considered satisfactory in view of the alternatives which are presented, (o) The effeot of an alkaline slurry on the paste crude acid was considered and it was found to be unimportant in case of crudes which had been steam distilled under either alkaline or acid conditions. - On the basis of the above work a process was written for Tetra Nitro CPC Crude 1 (Serial NUaSber 17964-A) which involved the urea ODCB fusion followed by steam distillation of the reaction mixture with dilute caustic soda, filtration of the ODCB-free suspension, washing and drying of the Tetra Nitro CPC as a product of about90# purity, 6, Optimum Drowning Conditions of Tetra Nitro CPC in Acid Solution Optimum conditions for drowning of the acid pasting solu tion were sought with the dual consideration of purity of product and ease of filtration. The most satisfactory conditions from a standpoint of purity and filterability were drowning in 10 parts water at 20C, or less followed by heating at 80-90* for a short time to effect an extraction of the pasted material, and give more rapid filtration. On the basis of the information in sections 4 and 6 of this report, a process was written to Cover the manufacture of Tetra Nitro CPC Paste Crude Acid D, (Serial Number 17964-B) 4- DUP050059014 7. 3emlWorks Performance Two vires ODCB fusions were made and subsequently worked up by steam distillation from 1.5# oaustio soda sufficient to main tain alkalinity. All steps operated smoothly and the filtrations were very satisfactory. The yield was about 84 lbs, of 100# material as 90# product. This is 71# of theory. The lowered yield can only be accounted for by handling losses and partially by samplings for control. The quality was excellent, showing purity of 98.6 and 100# on laboratory purifications of the two charges. The acid pasting proceeded smoothly, but filtrations in this step were very poor in spite of all efforts tp improve them. It must be admitted that at present this question is not satis factorily answered. An alternative process is suggested which may do away with the problems of filtering the acid paste by substituting a mill ing for this step. Patent Situation: AN-1894 covers the process for making Tetra Nitro CPC Crude E, Serial Number 17964-A. A!*-1475 covers acid pasting of phtheloeyanines in general. Thus, we are free to manufacture, these product#. U.S.Applica tion Serial No. 5>6,002 to I.C.I., which has been allowed recent ly contains product claims to Tetra Nitro CPC. Plans for Future Work: Future work will be kept to a minimum with efforts directed mainly toward control of the completion of the trial lot in Semi-Works. If, in future production of acid pasted Tetra Nitro CPC, serious difficulties in the filtration of the acid pasted material persist, it may become necessary to investigate an al ternative process, outlined below, in view of these difficulties which have become apparent.. only in larger scale operations. The following process is considered likely to prove more satisfactory: (a) Urea ODCB fusion carried out as in present process. -5- DUP050059015 (b) Alkaline distillation (to prevent corrosion) is carried out, and the weakly alkaline suspension is dropped into bricklined tub containing acid to make the whole sufficiently acid to extract all impurities. (This has basis in the fact that acidextracted material vas substantially the same in analysis as when it was add pasted and alkali-slurried. ) The product is then filtered and washed add free* (c) The press cake is slurried and milled to a form satis factory for reduction. This would eliminate the entire acid pasting step with the troublesome filtration and the problem of dispersing the acid paste for reduction by the substitution of only a simple milling Experimental: 1. Preliminary experiments on various reaction media JLNB 3660-86. 88. 89 and 100_______ _ A premix of 104.5 g. 4-nltro-phthalimide, 16.2 g. urea, 27.5 g* anhydrous cupric chloride, 2,7 g, boric acid, and 1.3 g. ammonium molybdate, which had been ball milled together, was added to 600 cc. ODCB or xylene or 750 cc. deo base, as indicated ' for each individual run. The charge vas heated with agitation to the specified temperature for three hours. The product was fil tered, washed with acetone, and dried. It was ground and slurried with 2 1. of 3# sulfuric acid at 90 for 4 hours* The product was filtered and washed free. The products were acid pasted in 10 parts 98# sulfuric acid at 0-8C, and drowned on water and ice at a temperature under 20C. The product vas filtered and washed. It was ammonia slurried and washed alkali-free. Effect of Grinding of Catalyst JLEB 3660-111. A premix vas made by grinding through the micro pulveriser the catalytic materials with cupric chloride so that 31 *5 $ contained the same amounts of these materials as were present in above experiments. 104.5 g. finely ground 4-nitro-phthalimide, 16,2 g. crystalline urea and 600 cc. ODCB were run exactly as in the above procedure DUP050059016 TABLE I A Summary of Various Preliminary Experiments on Preparation of Tetra Wltro GPO in Various Reaction Media Before After JLNB Reaction Yield Acid Acid ?66o__Medium_ .Temp^ ___ Fast-?-2??- .. 86 ODCB 150-55 90 99 98 Finely divi ded at end of reaction. 89 ODCB 175-80 86 97.5 95*2 Finely divi ded color. 111 ODCB 150-55* 80 100 99.0 Good physi cal condi tion* 88 Deo Base 150-55* 84 96 91 Thick in re action and stuck agi tator* Very lumpy at end. 100 Xylene 140* 26.8 71.6 (Reflux) Very impure product. ^slknttiBta:aBsssx.ss8SS8ias8:aesea8;asaBsarstt8sssa The conclusion was reached that the use of ODCB at 150-55*0. represented optimum conditions. 2, Consistency Series on Tetra Nitro CPC The consistency series vas made in order to determine the duplicablllty of the fusion in ODCB. The lengthy method of purifi cation used in conjunction with this series was essentially the same as that recommended by the I.C.I. A premix was made by grinding together through a micropulverizer with a fine screen, 76# g* anhydrous curpic chloride, 78 g. boric acid, and 59 g. ammonium molybdate. Runs were made in a 5-gallon enamel autoclave (ex. 55-81 Bldg.) The autoclave was charged with 4 1. ODCB, 732 g. 4-nitro-phthallmide, 221 g. of the above mentioned premix, and 1148 g. crystalline urea* The charge was heated to 150-55C. for 5 hours and then cooled to 50*0. It was filtered at 50 and sucked as dry as possible* *7- DUP050059017 One-seventh of the discharged cake vas worked up by soaking In benzene and filtering as dry as possible* It was then ball nulled In water and extracted with 90 cc. concentrated sulfuric acid In 1.5 1. water at 85-90*0. for l-l/2 - 2 hours, at which tine all odor of benzene vas gone. The material was filtered and washed add free. The paste was nixed with 2 1. water and 20 cc. ammonium hydroxide and passed through the Manton-Gaulln mill. It was extracted with 90 cc. caustic in the solution at 80-90*0. for 1 hour, filtered, and washed alkali-free. The material was dried, weighed and a portion was analyzed. A portion was add pasted in 10 parts 98# sulfuric acid at 5-10*0. and was drowned in water and ice. It washed acid free, pasted and yield was taken. TABLE II Consistency Series of Tetra Nitro CPC t^:ss=s;sg3sg=g;stx;pa;s5sggs;gsrsaag3;;ggcs3=cc:gggts;s:a:c:stt:aatimmq^mtnssacts;3:tg;=:3:gss;a:gsaifc;csrmc;: JmmLmmN.mmB.mm.3mm 6mmm6m.m0m 'mm. mrnmm_11__ mm m1 m2m m1m.mm mm 124*<mm <tmmm..an mm <m m1m a2mm5m mm m mm _126_ # Purity by 98.4 fVuU by N 97.7 by TiCla 92.6 % Yield based on Ou 78.0 on TlCls 73.4 # Purity 17.0 97.2 94,8 85.0 83.0 98.6 98.5 92.3 87.4 81.8 99.3 98.5 90.7 81.0 77.6 98.0 98.2 94.0 86.6 83.2 99.0 98,6 89.0 86.2 77.5 98.4 98.1 91.9 84.8 78.1 after acid pasting by Ou by N by Tide # Recovery on acid pasting 90.0 98.0 93.6 97.2 91.8 97.4 94.6 \ 93.7 90.6 98.5 92.5 99.0 90.5 98.2 92.9 98.4 89.1 97.8 93.4 97.5 86.0 99.5 94.7 99.9 89.7 98.2 93.6 97.6 This indicates that material of good duality can be made consistently by this method. Suitability of the product for Thlastrel Green 20 was checked by reduction of a portion of each Charge and conversion to color. These tests confirmed the uniform good quality of the product. -8* ....... ................... ......... ............................ ............................ DUP050059018 3. Effect of Varying conditions In Urea-ODCB Fusion In order to more fully understand the critical conditions in the preparation of Tetra Nitro CPC by the process used in the consistency series, the following variables were studied* a. Portion-wise addition of urea at 135-40*0. instead of initial addition in the cold* b. Heating of charge at 150-155*0. for 12 hours instead of 3 hours. c. Use of double the amount of ODCB. d. Use of less urea. e. Use of less ODCB. f. Use of less cupric chloride and catalysts. g. Use of recovered ODCB from steam distillation without preliminary drying. The procedure for these experiments was the same as that described for the consistency series except in the features noted. TABLE III Variation of Conditions of Urea-ODCB Fusion of Tetra Nitro CPC =s:a:s:S:sss:s=ssrsu=s:=s:s;=:s3:s:8ssss;.s;e33Ss:sa;Ks:=a;sa>KtESi3eata!ateasc:a=3S3B3=ttrs:s=:c:=c Variation from the JLKB Consistency Series ' 1 Tide Purity Before After Acid Acid Pasting Pasting Remarks 3660 145 148 136 157 158 159 Portion-Wise addition 80.6 of urea 11 78.5 12-hours heating at 79.5 150-155*w0. 84.0 Twice the usual amt. 78.5 of ODCB ,7 as much urea as 73.0 usual - 9- 96.3 93.0 94.4 92.3 97.0 97.5 95.6 98.4 99.9 95.7 99.0 98.8 Normal Normal Normal Normal Normal Normal DUP050059019 (Table III cont.) Variation from the mJmLmm.HmmBmmmm Consistency Series TlCla Purity Before After Yield Acid Acid # _Pastlng_^Pasting^ _Remarks^ Ml,** MmMMMMWM 3660 160 .7 as much urea as usual 50.0 94.9 97,6 Normal 164 3776 Half the usual amt. of ODCB 79.5 94,0 97,7 Very lumpy & caked 21 .8 normal amt, of premix 90.0 91.0* 97.3 Normal 26 tl 27 Used moist recovered ODCB 87.0 89.7* 85.0 90.0* 95.6 96.6 Normal Normal Worked up with alkaline steam distillation. Upon comparison with the consistency series it appears that v portion-wise addition of urea, long heating, and increased amounts of ODCB are without effect. Decreased urea, and decreased ODCB are definitely detrimental, while use of recovered ODCB and reduced amounts of premix are surely not harmful though the apparent increases in yield are due to the method of working up these charges which is more quantitative than that previously used, 4. Acid Pasting of Tetra Mltro CPC (JLNB 3660-133) Prom a uniform sample of extracted Tetra Nitro CPC (JLHB 5712-124- 1 & 2) samples were given the following treatment. (a) Ball mill in water and ammonia overnight and then extracted with 1.5# caustic soda at 80-90* for 1 hour. Wash alkali-free and dry. (b) Acid paste in 10 parts 98# sulfuric acid at 0-10C. Hold for the specified period at 0-10#C. Drown in ice and water equal to 10 times the weight of acid used and filter. Wash acid free and dry. -10- DUP050059020 TABLE IV Stability of Tetra Nitro CPC to Acid Pasting at 0-10*0. in 98# Sulfuric Acid =r=ses5=ssxassmeBc:ssB5e:s=s==:=a:s=s==ss==:=:cs=:5ss:cs.=:a=.=sss=:cr=;srs:ssesaJ5i*:s3:s:sxssn:ssc5Ssa:s=cs2r=r=:r:as=ssss==? # Recovery Total Solids Purity by Treatment___________________ _Cu_ N _TiCls_ Starting material -- Ball milled & alkali-slurried*100 Acid pasted for 1 hour 101.5** Acid pasted 4 hours 99.7 Acid pasted 24 hours 96.6 Repasting for 1 hour of the sample -- Previously pasted for 1 hour. 94.0*** 97.8 97.4 90.6 93.5 92.0 98.2 97,5 94,7 97.2 96.9 97.08 96.82 95.66 99.78 99.50 94.0 96.6 98.22 Control on purity of starting material High yield & lower ananyses indicate in complete washing or drying on this sample, yields are all felt to be close to the experimental variation, Lower recovery is {accounted for in impurity of the starting material. This indicates that Tetra Nitro CPC is quite stable under the acid pasting conditions which were used, and that the product can be safely conditioned for reduction through this procedure. A sample of Tetra Nitro CPC was pasted with 10 parts monohydrate for SO hours at 25-50*0. (JLNB 366O-I69-B), reduced and converted to color of satisfactory quality (JLNB 3360-186 & 3776-16-A) indicating that much more severe conditions than are normally encountered in acid pastings are without serious effect. 5. Purification of Tetra Nitro CPC from Urea-ODCB Fusion (a) Direct drying of ODCB Vet Crude Press Cake and Acid Pasting Without Extraction This method was considered, but was discarded since ammonia was given off under a variety of drying conditions to form tacky material which would be difficult to grind on a large scale and which acid pasted to give products of lower purity and in some cases inferior color (JLNB 3660-140-A, B & C, 143, 146, 147, 153, 155, 161-A, B & D), DUP050059021 Furthermore, it was impractical since the crude dried product could not be acid pasted in less than 10 parts acid per part of crude. Since the crude contained only about 42# Tetra Nitro CPC (the remainder being degradation products of urea, and unreacted starting materials), the cost of acid pasting would be materially increased. The evolution of ammonia upon drying the crude, and the resulting formation of impurities which are not readily broken down by dilute alkali or acid extraction is seen as a contributing factor of importance in the impurity of earlier charges of Tetra Nitro CPC, and accounts for "over-drying" which gave an inferior charge on Semi-Works drying while preliminary laboratory work-up had shown satisfactory quality. (b) Distillation of ODCB from Crude Followed by Drying and Acid Pasting Steam distillations were carried out on ODCB wet filtered material in either 5# caustic soda solution or Id# sulfuric acid solution and found to give a product which could be acid pasted to yield Tetra Nitro CPC of good quality (JLNB 3660-178). It was acted that enough excess copper ion was present to corrode a cast steel piece by plating out of copper metal. Corrosion tests with lead in acid medium showed approximate corrosion rates of .005 inches per month, while similar tests with cast steel in alkaline medium gave a figure of .0025 Inches per month (JLNB 3776-188 & 189). It was considered more desirable to use alkaline medium since cast steel equipment is more available and since this would provide an alkaline extraction to remove alkali-soluble impurities while acid soluble impurities would be removed in the acid pasting step, A typical experiment is outlined below (JLNB 3776-189-B): 380 G. ODCB-Wet filter cake was put in a flask with 1 liter water and 50 cc, 96# sulfuric acid. The mixture was steamdistilled till free of ODCB. The product was filtered, washed acid free, and dried. Wt. product - 93.4 g. The product was practically as pure as acid pasted material. By substituting 100 cc. 30# caustic soda for the acid, a product was obtained which, afto washing alkhli-free and drying, weighed 102 g. and was only about 90# pure. This is due to precipitation of copper hydroxide in the product. Acid pasting of either material gives product of the same degree of purity. -12- DUP050059022 (c) Effect of Alkali-Slurry after Acid Pasting on Quality of the Thlastral green Produced Therefrom In order to determine whether an alkali-slurry of the acid pasted material contributed anything to the quality of color made from either acid-steam distilled or alkaline-steam distilled crude Tetra Nitro CPC, experiments were run in which samples of each type crude were acid pasted in the usual manner, drowned at less than 20C., and then heated to 90 in the drowning water before filtration. The acid free paste was reduced at room temperature with 500 cc. 50# sodium sulfhydrate for 40 g. Tetra Nitro CPC. Duplicate experiments were run wherein the paste crude acid was treated with a slurry of 50 cc. caustic soda solu tion and 5 cc. cone, ammonium hydroxide in 1 liter water at 90 for 1 hour, followed by reduction as above (JLNB 5660-191 & 192). All amine samples were converted to Thlastral Green 2G, and dyed in the usual manner (JLNB 5776-19). TABLE V Effect of Alkaline Extraction of Tetra Nitro CPC on Idas Quality of Thlastral Green 20 ssasssrsBssasssassaeaBbBSBsessssaxasBBBBVBBsssttsavascBBsaabBSSBSiii; Type of Steam Distillation of Crude Tetra Alkaline Alkaline Acid Acid Treatment of Acid Pasted *2- Dyetest of Thlastral Green 2G _vs. _5560-152_ .............._........._ None Tf.yellow; v.si.strong Alkali-slurried Tr.yellow; tr.bright;equal None Not,yellow, tr.bright,v.si.str. Alkali-slurried Not.blue;equal ms'SSS'SSSSSSttmx9.teSSSS.SS'.SStSS.tSfftt9SStS^tS.88SSSSSSSiS^a:aSSStS:SSS91SSS88tS:tS8S8SSalSSSSkSr8S^tSS5flS85S No advantage is gained from the alkali-slurry of the acid pasted Tetra Nitro CPC. Either no alkali-soluble impurities exist, or they are removed by the sodium sulfhydrate reduction. 6. Determination of Optimum Drowning Conditions Preliminary experiments were made by drowning 17 g. Tetra Nitro CPC dissolved in 10 parts 98# sulfuric acid, in each of the following manners (JLNB 5660-174 & 175). -15- DUP050059023 (a) Drown in 1.5 1* cold water and Ice at lees than 20 C. (b) Drown in 1.5 1* water at 90-100 (c) Drown in 1.5 1. water at less than 20* then heat to 90* for 2 hours. (d) Drown in 200 g, ice and stir 2 hours, then dilute to 1.5 1, with water. (e) Add 50 g. water to the acid solution. Stand 1 hour and drown up to 1.5 1. (f) High turbulence drowning with 12 lbs. water pressure. The results indicated that methods (c) & (e) were most rapid while (a) was third in rate of filtration. Accordingly a solution of 25 g, Tetra Nitro CPC in 10 parts 98# sulfuric acid were drowned in the following manners (JLNB 5660-176). (a) Drown in 1.5 1. water and ice at less than 20*C. The diluted mixture was heated at 90 for l-l/2 hours. (b) 75 cc, Water was added dropwlse to the acid. After standing for 1-1/2 hours, it was diluted to 1.5 1. (c) Drowned as in (a) but not heated. Filtratians were made on 24 cm. funnel. The time to filter the original 1.5 1* and to wash with 2 1. water was recorded. The calces were washed acid free and dried for analysis. TABLE VI Effect of Drowning Conditions Upon Filtration and Purity of Tetra Nitro CPC t=te3sa6=stt:saac=ssa:=:a:s5=ss==:5sats=K=3:3sastso;*sixaBrsttss=a:sss:cr5s=:35sssrs5esm:floa:asssaaBBc*oesca=ese:a5rtttj Drowning # Purity Procedure_____ Piltration_Time___Yield* g. TiCla, _Cu____ N_____ (a) 5.75 min. 20.5 95.6 91.3 96.4 (b) 5.5 min. 20.2 84.9 85.5 88.2 (c) 14,0 min. 23.1 91.6 88.5 96.3 It is evident from these results that from the standpoint of filtration time as well as purity, a cold drowning followed by a period of heating is most satisfactory. -14` DUP050059024 7. Semi-Works Performance Charges 6 and 7 of Tetra Nitro CPC Crude E were run according to the Preliminary Semi-Works Process, Serial Number 17964-A. The fusion step was carried out in K-81 with extra ODCB added to make up for the absence of a condenser (525 lbs. were used instead of 180 lbs.). The charge discharged smoothly and controls on the product, after working up in laboratory. Showed a purity by TiCls of 100 and 98.6#, respectively (JLNB 5776-41 and 45). Distillation of a small pilot charge of Tetra Nitro CPC had indicated poor filtration. This was considered to be due to dispersion caused by too high concentration of alkali. (it is now felt tbsfc it was likely due to incomplete removal of ODCB in the steam distillation.) The caustic coneentratlon was decreased to 1.5# in accordance with results obtained with laboratory control (JLNB 5776-41)* The process was operated at this caustic concentration. Distillations were run in K-9 (a 90-gal. iron kettle) and carried to the point where a liter of distillate contained no more than 5 cc. ODCB. The distillation kettle was checked for alkalinity to Brilliant Yellow Paper. The charge was filtered, and washed alkali-free. It was dried at 80-90wC. and ground to 40 mesh. No difficulty was encountered in any of these steps. The dried material, after grinding, amounted to 95 lbs. of 90# product or 84 lbs. (100#). This represents a yield of 71#. The low yield can be accounted for only by handling losses in equipment which was not entirely suited to the procedure. Acid pasting of the product was done as in the Preliminary Semi-Works Process, Serial Number 17964-B. The pasting operation proceeded smoothly, but the drowning step was not satisfactory due to difficulty in filtering the product. Yield on the entire lot of four small charges of 20 pounds was 79.5#. Most of this loss occurred on one charge, due to leaking of the press over the long period of filtering and washing that was required. Conversion of this material to Thiastral Green 2G will be covered In a later report. Blblidjgaphy} I.C.I. Report H-6004 JLR-52-108, No. 2; Serial Number 17465 JLNB 5660 & 5776. Submitted for typing - June 15, 1942 rvw - August 26, 1942 DUP050059025