Document y2agYRByaRk1o3xO6JMebM5D

B.F.GOODRICH CHEMICAL COMPANY Inter-Organization Correipondence To J. D. Franklin Location Calvert City Laboratory Date From October 18, 1974 R. L. Parrish .r SubKC F.FFICIF.NCY OF CARBON ADSORPTION - CARBON DISULFIDE DESORPTION IN AMBIENT VINYL CHLORIDE TEST PROCEDURE <>b j*c t i v<* !> t rm i r>* thi* carbon adsorp t i on-carbon disulfide desorption efficiency as they r<*uto to ambient vinyl chloride testing. Cone 1usions With limitations pointed out in the text of this report, conclusions ore! 1. Efficiency of the adsorption of the ambient vinyl chloride onto the activated carbon is 99%. 2. Efficiency of the extraction of vinyl chloride off the activated carbon with carbon disulfide is 100%. Fnture Course of Action Carbon tube testing for ambient vinyl chloride, under tho conditions noted heroin, will assume 100% efficiency for adsorption and extraction of vinyl chloride in relation to the activated carbon. Discussion The vinyl chloride ambient perimeter surveillance program will employ two types o f samp 1ing. Grab sampler* arc to bo taken on tho wind rectors. tharconl tube samples are to bo taken at stationary points over a 2** hour sampling period. Chris Oraborn is looking for a D.C. powered pump that will aomplo over a 2< hour period. Until cne is found, an A.C. powered Millipore pump io available. The selected sampling rate is lOOC cc per minute of air. Over a 24 hour poriod, this rate will provide enough samplo volumo (at the expected VC1 concentrations) to assuro good analytical accuracy. It is ossontial to know tho adsorption efficiency,in respect to vinvl chloride, of the activated carbon at this sampling rato. A laboratory experiment was carried out wherein tho carbon adsorption and tho carbon disulfide extraction efficiencies wore determined. 4006 BjFG:I- 390 % -2- Snmmary of Lab Work A sampling train is prepared using throe 150 mm polyethylene tubes each containing 8.3 grams of Nuchar VV-H activated carbon. Teflon tubing i* used to connect the tubes together. The sampling train is connected to a gas cylinder containing a 48 ppm vinyl chloride in air standard gas. A dry gnn meter is usod to measure the total sample volume. The standard gas is sampled for exactly 8 minutes at a rate of approximately IOOO cc per minute. Aftor sampling, the tubes are extracted with carl-on disulfide and analyzed in the manner used for personnel monitoring testing. Calculateons A. Theorectlcal Micrograma The theorectica1 total micrograns vinyl chloride adsorbed is calculated from the total volume of standard sampled multiplied by the standard concentration! Total uga VC1 volume x 1 mole air X std. concentration X mole Vt. VC1 molar volume 7.924 'iters x 1 mole air x A8 x 10 ^ mole VC1 x 62.5 x 10 ^ uq VC1 -966 ugs VC1 24.6 liters 1 mole air mole VC1 Where: Volume > volume gas samplod as measured by dry gas meter > 0.280 cu. ft. x 28.3 liter/cu. ft. 7*924 liters Molar volume - 22.4 liter x 76O mm x 296 * 24.6 liters 751.3 mm 273" Standard concentration 48 mole ppm or 48 1 10 ^ mole VC1 1 nolo air Mole Wt. VC1 62.5 x )0^ ugs VCl/mole VC1 11. Sampling llnte Sampling rate Volume sampled 7-924 liters 0.990 liters/minute or Time of sample 8 minutes 9yO cc per minute C. Analytically Determined Mlcroqrams The analytically determined total mlcrograras vinyl chloride adsorbed is calculated from the analysis of the extract of each tube. A blank (14 ugs) is subtracted from the analysis of each tube. The bln.it is dorived from the instrument response for a CS^ extract of 8.3 grsas of fresh activated carbon. BFG-,1- 391 3- Calculatlon 1. Calibration of Gan Chromatograph Method: A A8 mole ppm vinyl chloride in air .ui'ftura ia the cali bration standard gas. With a Precision gas tight syringe, 2.5 cc of the standard gas are injected into the instrument. The area response is recorded and calculated. This response is divided into the micrograms vinyl chloride in the standard injection to obtain the GC calibration factor. Calculation of GC factor (C factor = Std. injection x 1 liter x 1 mole air x mole cone. std. x mole Wt. VC1 1POO cc mole volume Instrument response = 2.5 cc x 1 1 i ter x l mole ai r x **8 x 10 ^ mole VC1 x 62.5 x 10^ ug VC1 10CO cc 2**.6 liter___________1 so 1 r air________________1 mole VC1_______ Z 2^*837 mm* 9 1.23 x 10 ug VCl/mro Whore: mole volume * 22.U liter x 76O ima x 296 2*t.6 liter 751.3 mm 273 Instrument reMpon.no = I38.6 mm x 1.1* mm x 128 2. Calculation of Dilution Factor The dilution factor ia the ratio of the microlitors extract injected into the instrument to the total volume of the extract. There foro: D m _1___ x IOOO ul x 50 ml - 2 ul 1 ml It 2.5 X 10 3. Micrograms VC 1 per Tube Calculation 1 Micrograms VC1 per tube . (GC factor x response x dilution factor) - blank Tube #1 (9-26-7**) _c o 2| ugs VC1 (1.23 x 10 uga/tntu x l66.< sax x 0.6 mm x 32 X 2.5 x 10 ) - 14 ugs - 968 ugs *' Tube #2 (9-26-71*) 1, ugs VC1 (1.23 x 10 ^ ugs/mro^ x 6l m 1 1,3 im x 1 x 2 ,5 Jt 10 ) - 1^ ugs 10 ugs BFG-I- 392 -4- Tube #3 (9-26-74) "*5 2 4 uga VC1 - (1.23 x 10 ^ uga/mm x 48.6 mm x 0.9 mm x 1 x 2.5 x 10 ) - 14 uga 3 0 ugs 4. Total Micrograms cn the 3 Tubes Total uga 3 tubes uga Tube #1 * uga Tubes #2 ugs Tube #3 " 968 uga 10 uga 0 uqs 978 ugs. D. Adsorption Efficiency In routine sampling, a single carbon tube ia in the sampling train. There fore we are interested *n the vinyl chloride adsorption on the 1st tube (in the experiment). So the adsorption efficiency is here defined as the percent vinyl chloride adsorbed on the 1st tube. Below this efficiency is calculated by two different methods. In the first mothod, the percent adsorption efficiency is the ratio cf the analytically determined VC1 on tube #1 versus total analytically determined VCl on the 3 tubes. In the second method, the percent adsorption efficiency is the ratio of analytically determined VCl on tube #1 versus the theoretical VCl purged through the tubes. The two methods are in good agreement ascertaining that essentially 100% of the VCl in the air being sampled is adsorbed on the 1st tube. Calculations Method 1 % Adsorption efficiency tube #1 - ucs VCl tube #1 x 100% ugs VCl on 3 tubes 968 ugs x 100% = 99% 978 ugs Method 2 % Adsorption efficiency tube #1 * uga VCl tube #1 X 100% theorectical uga VCl 968 ugs x 100% - 100% 966 ugs E. Extraction Efficiency The extraction efficiency is a measurement of the ability of the CS^ solvent to "wash" the VCl off the carbon into the CS, . It ia defined heroin by the following calculation: ;BF.G-I-. 393 -5- % extraction efficiency ugs VC1 tube #1* If (theoroctical ugs VCl) (% adsorption eff. Method 1) - 968 uge x 100% - 101% (966 uga ) (99%) Comments in Conclusion of Report This experiment la Intended to give a relatively precise estimate of the adsorption and extraction efficiencies. This is essential to analytical accuracy. It is recognized that scmo parameters that could affect adsorption are not evaluated in thie work. A high concentration of contaminants (humidity, other hydrocarbons, etc.) can decrease the efficiency. The lab work was done on September 26, 197^ gflj& s r . jc R. L. Fairish RLP/lw C. L. Woods, Jr. D. B. Schrock E. E. Atkins R. V. Edwards CTF (Avon Lake Development) 1 STAFF TECHNICAL SERVICE REPORT NO. 303 B. F. Goodrich Chemical Company A DIVISION OF THE B. F. OOOORICH COMPANY DEVELOPMENT CENTER , A METHOD FOR ANALYZING VCM AT THE PART-PER-BILLION LEVEL ///- M. M. O'MaytoGihd J<^|^ Qulsonbcrry Dace Completed: June 5 , 1m97v4. Peojeect No.: 3690 Abstract: 'Y o Date Issued: Jurie 7. 1974 Department No.: 5026 A gas chromatographic method based on flame ionization detection and coconut charcoal adsorption has been developed for detecting VCM in the atmosphere at the l part per billion (ppb) level. The basic principle involves the adsorption of a 250cc air sample on activated charcoal contained in the sample loop of a gas chromatograph. The loop is heated to 200*C. to desorb VCM and the VCM is then analyzed chromatographlcally. A calibration curve ranging from 5 ppb to 280 ppb was experimentally determined. The curve was linear and a linear regression analysis of tho data revealed a 3.0% deviation In the slope of tha calibration cui.c. At the 20 ppb level, a 9Z deviation in reproducibility (5 runs) exists. A complete description of the method is provided. The general method is potentially applicable at the parts-por-trilllon level and lower. Dtstr lbut l-n: Akron E. K. Bean E. B. Katzenmeycr R. W. Strassburg M. N. Johnson Brecksvlllc R. J. Fawcett D. E. Ley C. H. Lufter Library *R. A. Krueger *A. R. Sicbort *H. (Col.) Tucker P. Znkriskl J. Pausch Production Plants PLant Manager Technical or Prof. Services Mama c Cleveland 1TC A. Vittona B. A. DiLiddo *R. J. Fulton *D. E. Wright E. J. Sehm E. G. Schwaegorle Managers G. E. Thompson B. M. G. Zwicker-M. E. Roha R. M. Krcagor A. L. Schultz F. J. Donat C.T.F. (3) R. D. Scott ITL - R. J. Mayer (2) J, L. Nelson L. B. Crider E. W. Harrington F. E. Krause H. Writemate C. R. Flynn J. G. Quisenbarry M. M. O'Mira W. C. Holbrook E. A. Collins *W. F. Blxby *W. E. Brodino E. G. DeCaplta J. L. Dorsch *K. C roe no *G. H. Motzgor *P. D. T'cry K. J. Kaminski 392' iort >FG-I- 395 j 1, InCrmlncCton The nc-od to analyze vinyl chloride monomer (VCM) In the low parts per billion (ppb) range la obvious as monitoring proceeds away frem the point ^ source. A number of approaches can be used to monitor at this level but the most obvious and best developed method Is based on the use of gas chromatography. Since neither flame Ionization ncr electron capture are sensitive enough to measure at this level (recent edvances in mlcrocoulometrlc detectors might make this a viable approach) a pre-chromatographlc concentrating step Is called for. The literature contains a number of publications In this area but the articles by West^G anu School^-) provide an adequate background to this typo of approach. About 3 years ago, School personally described to me his work In this area. Ills studies on the thermal desorption rather than the solvent desorption of coconut charcoal were of Interest to our pyrolysis wo-k at that time. In fact, we have previously studied the thermal desorption of materials from molecular sieves.(3) West, In his work, described the use of gas chrom atography to analyze air pollutants which were thermally desorbed from activated aLnmlna, silica gel and charcoal.d) The work described In our report is an extension of West's method, optimized to the analysis of VCM in air and modified for purt per b11 Lion analysis. II. Analvclc.il Approach In essence, the sample loop of an 8-port gas chromatographic sampling valve Ls replaced with a 6" x 1" stainless steel tube which contains ~-0.2g of coconut charcoal. Two of the sample ports are used to flush a 250 ml gas sample container with helium through the charcoal bed. Once this flushing operation is complete, the charcoal bed is heated to 20Q*C. At that point, the gas sampling valve is actuated thereby diverting the chromatographlc carrier gas through the carbon bed and onto the chromatographic column. In this way, the VCM Is removed from the carbon bed and deposited on the chromatographic column. A typical analysis la then carried out. Thu limiting, factor in terras of sensitivity in this analysis is the 250 ml sample container. With this constraint, analysis is limited to -.1 partpe r-b 111 ion . III. Problems 0 Although the approach was rather straightforward, two problems arose which should be recognized by those attempting to duplicate tho procedure. The carbon bed contains glass wool to prevent carbon movement and loss inside the sampling loop. Wo found that unless the glass wool ls thormally conditioned, ghost peaks occur In the chromatographic analysis (sec Appendix). The second problem occurred In making up standards at the low part-pcr-billlon level. Our previous work in preparing standards Involved the part-per-mlLllon level and at that time no problems developed in these analyses.However, In the part-por-billlon range wc noticed that Initially It was very difficult to reproduce our standards especially In the 5-20 ppb region. Tha problem was finally traced to rosldu.il VCM in BFG-I- 397 s 2 our make-up air. An analysis of the air near the air compressor*: Inlet (roof of boiler house) revealed 100 ppb of residual VCM. We solved this problem . by putting an activated carbon bed on our air stream. However, to assure ourselves of true zero VCM grade air, all standards were prepared from cylinder air which was tested for VCM before use. Once these two problems were rcdcgnlzcd, the analytical development of the method was relatively simplc. IV. VCM Calibration Curve All standard:! were prepared by mixing a 19 ppm VCM standard with air and flowing this mixture into the 250 ml sample container. With our flow meter ranges, we are limited (lowest) a 2 pph calibration standard. A 1 ppm VCM scandaid will bo ordered. This will allow us to prepare standards ' ' ' r i >,i! : >cn- rv. T'''lc l c ii a -u: ..-ary of ! . ' ;....... * '' gas chror.. togra/.ilu p.uk areas for thus .* s: :.! . r.J.. .i. ... c. 1 . a: art- al.:.i 'i -,.n in FI -jure l. A typical c'-.r vie.; irnnhlc .* I vi|* at I'"1' l 1 : . t-i F! :-,.ire 2. It l. I:-; - i r. to n thi t the chr.-*. it.* !' was not at the kv*sl .sensitive setting during this 5 ppb analysis. If it wore, the peak would he 4 times the size shown In Figure 2. Thus with a steady baseline at maximum sensitivity, an analysis of L part-pcr-billion of VCM is quite reasonable. The gas chromacographlc data in Table 1 was hand calculated because of a malfunction in PACE (off-Llno computer). PACE-obtained data (see Appendix) v.i ; reliable above 20 ppb but for VCM concentrations below tills, the data was not se1i-consiatent. A linear regression analysis of the expanded calibration data in Tabic 2 (see Appendix) yielded the following equation: [VCM] ppb - 1.99 (C.C. Area) - 4.81 ppb The slop" was l.1)1' .04 pph/nrea with a correlation coefficient of 0,C9C. The excellent linearity of the cal ibr.st i.<n curve la Indicative of a rxteor of important phenomena. If thcro is anv loss of VCM during the purging operation, it is independent of the concentration of VCM, Also if any VCM remains on the charcoal, this too is concentration independent. Wo were concerned about tills latter possibility in that wo might bo building a "memory" on tho charcoal bed. However, repeated blank runs have been carried'out and to dace this docs not appear to be a problem. If very high levels of VCM arc deposited on the charcoal subsequent analyses could shown a "memory" to this initial deposition. 3 L Table I Calibration Data for VCM Adsorbed On Carbon and Chromntogrophlcally Analyzed After Thermal Desorption VCM Concentration (ppb) 5 10 13 20 40 60 120 190 280 (a) Penh Area 2.5 5.0 6'2 14*9 22.4 35.1 69*7 90.0 140.4 a" Defined as "the peak holght times the peak width at half height time* the range times the attenuation". PACE data was not reliable In the 5 to 20 ppb region; the PACE problem is correctable. These values arc average values of 2 cr more determinations. 3929 7 BFG=i- 399 F ig u r e l : VCH R e s p o n s e A f t e r T 't e r a a l D e n o r p t iv>n fr o m C h a r c o a l Figure 2: 5 ppb Vinyl Chloride I I i i '' ' i h 'H-J_LLr! : i 1 ~ rs I I VCM . t I --rrt i , BFG-I-; 401 6 V. DUc u.q* Imi Two approaches W're possible with this technique* One (that chosen) Involved iiakliip, mi'- carbon adsoip:. ion becJ for the gas chromatograph and sampling with the 250 t.il ..Inss containers. The other approach Involved making .1 series of carbon beds .mil sampling directly with these. Wc chose the forv. r nt-ihod for a number >f reasons. Ultimately we had Control over the adr irpt I ui x;-r 1 --out. In the field, sampling with the. sampling contain' r. neither l hi sanplltii'. r.ile or the sampling time ore especially critical. for oe.c-pl. . -lamp l iu.t at a rale of l or 2 'Iters/mln. for any period ! 11 a t > \mimiI.iad.-qo.i le . However, much tighter control r ho.', the a.i up l i n rate and the t l e. would be absolutely critical If sin-.il a -a . c oa with tic r.iili.e >u d directly. We al'o checked the f lirw..iete r on one it the pnrlahle pumps with a precision flowmeter and found It t o he out oj ea I i hra t l on liv I l In terms of sampling with the glass veiiel., in! d 'vl.it ! ! I.-, uni ;i ri mi. However, it Is not un Important In s11 a . : : h in. ce e >n ... d . i,i.ir ,mv :in.i Ly i - is attempted, a 11% error l- atr. hic.-d i .r- ill.i t.dv. Another demand wo placed "i\ tlh- analyst i was rapid turnover. A rei nr ae f ant a h i 1 nr.r do-ions t rated Clio problem If too much material i.. id-. [;. I mi i tie charcoal . The chromatograph must bo baked out aft.-r ev. rv ran. With t .hi t. w:ui!i l le exhaust samples. It took an hour to clean the cli r-via to ;ra;ih ot the high nulling components that were trapped out of ib hhaii.t . Tin... of course, would be no problem If we had a number of chm a l" i; -! i . available lor the analysis. In light of the number of sample ; put e.. . a to ii- inn. iapid Lui'novei' was a necessary constraint. Tills seemed to ,-l inmate direct use of the carbon bed because of the other component-, laat v.u.K. :>. deposit, it in relatively high yields. Finally,.the s.mipl i mi; rate was a potential pr.d,lea from another standpoint besides control. Very little carbon (^.(J.2g) is Involved in the adsorption. We initially started out I:di ,.f carbon bit this had to bo abandoned because It led to V r;'.!li' d.i e!i I-.v Ml ..rapli ic peak. To keep toe adsorption e t 1 lc 1-111' ill Ml. th 1. Cell!.. iue l .1 are purged at a flow rate of 100 cc/mln. or l/I ()t.h t ' mi -pit'!-, rati t h.a r would, he used in the field. Kfl icloncy might be ., 111 he at this It'd! rate especially in light of the small amount of earn .'-a that must h-- used to obtain acceptable c hrntnn togrnph ic results. Needless to say all of ih.vsc roblei.is can go overcome Lf analysis below a parL-per-blllIon Is Important. Efficiency studies can be carried out, the portable pumps cun be fitted with high precision flowmeters, and the chromatographic analysis time can be lengthened, for example. In. terms of developing a rapid, reliable method for analyzing VCM In the 1 ppb region, we feel the method chosen was the best compromise. 6 13 l .- 11 . . l< 'll Two approach*s u-ri' pos : i !>1 with tills technique. One (that chosen) liivlv ! r-akinp. c.ii'iiiMi ;ul ,ir|i t i >n hod fur the ps clitom tograph nntl >.itl i ;i.'i Hi th. ; Mi :il ;l.i: . i imii.1 ire rs. The uther approach Involved maim .i '.ei i. M el carl.nil heils .mil M.ieipL ln>; directly with these. We chose nil .r :lh.i.| It ,i nnnih. i .f i -ams. Ultimately we had control over l'e 1 I -1 : I i 'll 1 II .III . In l he field, samp l Inf. with the snmpl ing *: ie' : i. Me i t ii. r i ru-iptier r.it*- or the i.irip 11 lie. t line an* especially cm;-. i. I'u r . I- . -..lit,;.l . ii._ ,ii .i rate "I l or _ * i lera/mln. for any ; :: : I, .. i .i w '.:e. ,|. . s .ul. .jn.ite . However, noth tighter o:i I . i s ..ii , 11 in , rote .tie! III. I ir.te would In- nhsol uti-1V critical l ' I I h 111- i -. t '. i e l dill e 11 V. We .11 -.1 checked the I I - S : : el I.. I lie port .ill i, , i:. ... w 1th .1 precision flown* ter and found II .1 ' ll I'o-.it I on 11v II . in tern.i "I sampling with tie- glass : :: : .: - ; in: :i , i . II. r.f vc r. it is not ultima ertant In . ' ! 1 :. I ,. e.- .1 n.11. I . l.i a t tempteda 11 /. ii . i i !o 1 i . 1 I.i I 1 .- . Anotls i ! .... pi.us,I :i : h. .in.ilvM . i :s rapid turnover. A : .1 .. I, , ! 1 r ........... . :t i at eil th- prohlen if too much. -i ' : . . s .. ; ., : i i i i ., i . i: -.v. h r e>: :l. l i o ;r .1 pit w-.i > t he halted out all i v e - r.n . I ,.uh . -.haii.L samples, it took an hour to el- ie. t 1 111, III I 'll ill th. hi. h '.oil in,; components that were trapped ei- .; . I'nis. ... v.-.m'd he no prohleiTi if we had a number I chi ' - e V. ii hi, : r i it. eialv ah If. I i gh t of the nunher of a-- e i - tan n a i n ion. i.ipi I imnove. as a necess.ify constraint, i i i i ... .1 to . ii iu.iI .- ,lih i i u.. o! th.- carbon bed because of rite other CO a 1 I' inn; -.. . .1. ....... ... .: : la; lv l v h i ,-.h yields. Finally. .the s.uap 1 i late w.e. a potiuLi.il piohi..a 1 roia another standpoint besides control. Very Little caruon l,.U...g) is involved in Luo adsorption. Wo initially lari. I -it 11 > . ' f c.irh'c !-,t this bad to be abandoned because it led ' r !. .1 '. , |-. ;. ,:; i ;; p..:k. To keep 1.1 u ad s orp t I on it ;. - 'i. i i. .. i. i ..in ... i a;- purred at a f 1. rate of 100 cc/mln . u I '! ' i' , ...| , . .: ; , ihi; -... e.l I u: . ! In `lie field. Kfiicicncy ui i h. . ! 1 t c p--c i a l 1 v in 1 t r h t o| 1 lie srwi 11 amount Ol ca. a th it; : ' 11 ! [ .. , .j. ta i n aceepi able c hromn tograph ic results. Needless to say all ,if iee-.i rohleiis can no overcome if analysis belt, a parL-pe r-b 11 1 ton is Important. Kfflcloncy studies can be carried out, the portable pumps can be fitted with It igh precision f l owmo to rs, and the cl to, -..! tograph ic a na L ya i ; time can be lengthened, for example. In. terms of developing a rapid, reliable method for analyzing VCM in the l ppb region, we feel the nxithod chosen was tin- best compromise. 39297 BFG-I- 403 Adih ii! ' x I t'ruootUn, il Iii1om:i.iL ion i\o 1-U: i n o To The AiwiLvat.s of VCM at Che 1 ppb l.o vo l I 1 If* : Itz: ^ir. : H.-wl* - lit-Packard Mulct 571CA i 7. r> cc /miin . I | factory specifications Dnliunn Temperature: Initial - 80*C. for 2 minutes program - lfi*C. /minute final - 20()',C. for 2 minutes Inject i mi i'oit Te iap. ra L'.i re : 150'C. ilrl.vl i I'. ... to I ::r,. ; .! Ml'O . s" i'11 111.a !l tj:;, AO/SO m. :;!i ; l . i * - A 1 ' ! ' : i > ill.* . coins m t .1 In i i'.i; O.'lOti-, of ri.ih-r Scientific ' : i! (Cl! 1 ,<; *} . . V 5-M83-."). :?! i l .if >-}-. was prepared. ! .i: *.. i li .ii.! . ol tho bod to preven ta.ivciiienf. It t > l^o . liu 1/ Lolu.r.o i . ilii'ii placed in a vertical position, *>>: I v t: l/o" .. Lo in! sstool tubin', and connected to a t , i< 1 by Lh: \.wf\ L*>o;>* The* phot t.n n A. I.-: (i'.ni IV! shows (ho o..is samp l lag valvo and carbon bed. Tho * i : li -i h'-.-Lin . i\X and a tl; rnviouiplc was Inserted to ;:ii:u:.or i. p, r.iL i:o. Adsorption i s carried out at 23"C. and desorption at 2b'0"C. ' i * c.m\ Ik1 used t.i> Ini-. : i.r't- i_hc carbon bod io U.- , iii-. cm t. l-. i ! ;.!s . l\.-o oL t!i . ports; are used lor t he carbon bed, two of Uu` . s s v' 1 tl*.. c.u'!:iir, b t! a.wJ i.wn of lis p-'-ri. - s i i ... I lo ! lush Us.- c.'ivls >n bed onto the c ur cilia Lugvuph ic Column. Tile two rcn-i i u tug ports are "Looped" together to provide a by-pass for purging. Tile loeat Lon o 1 the lie l Lum Line, gas sampling container, effluent line, etc. are shown below and labeled accordingly. Two maturing valves arc also shown Ln the photograph. Those are necessary to cLosu off tiic carbon bed during tho lieat up pmeedure. BFG-I- 405 9 A - helium purge line to bottom $ of sampling vessel B - sampling vessel C - metering vn Wes for lnolnl Ing carbon bed 1) - 8-|>ort gas s.'iir :1 I ng valve K - c.'irlmn bail F ' t In' I`.:v H'< 'll |> 1 I' c.irlmn bed VCM I ! I h It. the pi'oi dural n ' 11: L ; am I y1 it;. : .'.t. .! ..iimil in . vs.ie 1. com .lint iii; vinyl clilor tdv mon. v is ituort.he samp 11 m: vn 1 ve (in' phot ogcnph) the helium purge line, teed from l ne through n metering valve, Is connected to the bottom. of the vess.-l. The two meterliiH valves on the gas sampling valve arc tlie stopcock at the top of the sampling vessel Is opened, followed Lopeock at. the bottom. The helium flow through the vessel onto on bed (at llVC.) Is maintained between LOO - ILO cc/min. for tes. At the end of this purge time, the bottom stopcock, top stop- the two metering, valves on the sampling valve arc closed (In tha scribed). At this point, the heater on the carbon bed Is turned on. 10 i'ii. t ii'j i . 11 u i v on i.rn- ix<i i . a i i i to rim- to 22'j'O. (about 1 minute after lit- v.i1 >/ !; a i i. ii 11 '<!) . Wo Ix'iifvr tii is may be necessary to avoid memory on tix e.iih-n ' cl . lit- lx'.iter on t .be boil l:. then turned oif. Once the valve Is leloil .1, ' !: i I, i t -1 r;i | ill i c pl-cess is InH l.ltml 1(1) 2 minute delay at Mil'c... (.') . I .'Oil't;. it 1h'C./minute, (l) bold at 20O*C. for 2 minutes) . vi :- .a. i. _< . i i .i In t *i: ............... I !: .itvr.'i .1. l.i cent.lined m Table l will be expanded i in.-1 . 11 : i.. t.. i. A *'l all l.e, ii - ' : 1 ' n : 1 1 ti ; 1 1 !' P.U'i. q i v.i:. not a- 1 f-e i : I :i Le 111 . A summary i.: l-.ioi; ill 1 a i r:.. rd . - il.a `P,\l'.!. .iud hand calculat'd analyser. are -1. .W ill-;' :h, .-iior m 1'Acl. -ah i l c tunnlnf. the 10 ppb V 1 l ' ! - l : i - -' til- V I'. : t e >' I 1 1 V r- -i :i : !; -. I I a tUi;e! ' : ;' c .U IIt:i ! l . : h i :. .-i it a1- . i -.-a 1.1 m. !!:-a r, . !'v --i An i, .-in . i'AWK -.'..La :a - i -lata. In the . c a: a : i, tie VCM la 1 !:1< r . * ' . .. - I , II I !'A(. ;i I" -1) I e . lii- 1 ' "U.i; -n . > ii ; i i a* I -;: i . ; l r t v prcvrouslv ri-nti ii-.'J -..an .ie te r-.".i ru- d 1' - ' I'ii- ,ni . da i a . While tie- I.!-) .inh data sluv.-i a greater spread, this d ' . i I sit h--.;an.e a| '.'Id! c. 'a r.a i i. '..l r l oil in the make-up air 'f the The linear regression analysis was carried out on all the data in Td>:- ' . To '' ' 1 -I-1-. I:!.-: relate la the re -.'.re salon analysis: ill l.'l I e.-. : 1 . n . re - : -'..SI :-L Tin- general. technique described in this paper can be used in a number of other applications. For example, It can be used for analyzing pollutants or. a tin-mill conductivity gas chromatograph where Increased amounts of sample are reip.itrod. lor the analysis of compounds that are not sensitive to flame Ion i .'.a t Ion. this tochulcjuc coupled to thermal conductivity gas chromatography uviy he very adequate. The true potential of the technique has not been evaluat'd, It offers the potential to analyze quantitatively at almost any level. 39297 - ^ 4 #-- * * BFG-I-407 1 Table 2 TACK mid Hand Calculntcd Data for VCM Standards dnrd, ppb 5 *1 10 10 .*n .* 11 lo Hi r. 13 60 I'm; l.'o 120 no mu 1 ) 2 80 1 i, ) PACE G.C. Area Hand-Calculated^) .000993 .000393 rl CNI 2.60 . 0090-'. .Olf.16 5.10 3.95 . 0063 3 .()()(. 99 .00711 .007 of, .00707 13.0 13.5 13.8 17 8 15.2 .0111 22 .3 .0193 .ooed 6.50 6.00 .0187 .0173 33.9 35.3 O'. 10 . 033 7 .0292 81.9 69.8 57.7 .0338 . 0338 93.3 86.6 . Of.3 3 .0711 133.2 13 6.6 G) Peak height x peak width x attenuation x range. a 1.198 MV full scale G.C. recorder. These values arc based on BFG-I- 408 12 Rc fc ro ncc n 1. I'. W. W.-st, I't-.nl., Analytical Chemistry, 30. 8, August 1958, 1390. 2. L. i). Millie, ft...'tl., American lmlustrl.il Hygiene Assoc. Journal, 31. March/Aprll IT/U, 225. ) M. M. H'M.ifi. .1. A. Nlk.ir.i, "A I'yrolys l s-0;is Chroirn t ogrnph Ic Technique l;"f I-* : i ! Vie. . A'1-i..i-l.f.l Mate r (a i..", I.O.C., 9 i'J< M- ;1- 1'm. A. t.e.s, It. I-'. Co.nl r Ic h Technical Report, February 28, 197A. 39297 BFG-I- 409