Document X7dvRGRYn4BKq3xEpjypMk7Nw

AR226-3336 DuPont Fluoroproducts Washington Works Melts Technology Report Contribution Name: Stephen R. Peck Date: 5/2/03 TA B LE OF CO NTENTS (A B STR A C T S E C TIO N ! I. SAFETY, HEALTH AND ENVIRONMENTAL A. ANALYTICAL DEVELOPMENTS FOR DETERMINATION OF AMMONIUM PERFLUOROOCTANOATE . Page ft KW1C: [AMMONIUM PERFLUOROOCTANOATE, APFO, C-8, GC, HPLC, Triton X-100] rhangfts to three chromatographic methods for the determination of APFO are described. Included are revisions of gas chromatographic methods for dry resin and air samples and a rapid method for determination of APFO and TritonX-100 in aqueous samples by liquid chromatography. (STEPHEN R. PECK) Company Sanitized. Does noi contain TSCA CBI TEFLON TECHNOLOGY REPORT ARTICLES SECTION I. SAFETY, HEALTH AND ENVIRONMENTAL B. ANALYTICAL DEVELOPMENTS FOR DETERMINATION OF AMMONIUM PERFLUOROOCTANOATE STEPHEN R. PECK, S. Hopkins, M. Jacobs, S. Mayle, M. A. Parsons, M. E. Reeder, D. Riggs Sum m ary Changes to three chromatographic methods for the determination of APFO are described. Included are revisions of gas chromatographic methods for dry resin and air samples and a rapid method for determination of APFO and TritonX-100 in aqueous samples by liquid chromatography. This report describes recent analytical method developments intended to enhance the effectiveness of the determination of APFO content of various sample types. Changes to three procedures will be discussed separately. A reference to this report will be included in the method procedures to document the technical basis for the changes. Part I: Determination of APFO in dry resin by gas chromatography: Tsahmispmleeitshtordeaitsedpewrfiothrmaecdidiicn tmheetfnaanjocRoonctornovel lratbth2e8AWPWFO-3t6o9i0t.s mInetthhyisl pesrtoecre.dTurhee, tehsetedrriys extracted into hexane and analyzed by GC-ECD. An internal standard is included, and the response of its ester is used to normalize the peak for the methyl-PFO. : Originally, WW-3690 was used almost exclusively for PTFE fine powder resinsJput th ^ application of the procedure has been broadened to dry FEP and PFA f l u f f Q ^ ^ H fluoroadditive, process filters, and other dry material. Company Sanitized Does not contain TSCA CBI WW-3690 requires a significant amount of sample preparation and handling compared to other GC methods iiflK L ab. One complication was the use of a spuming riffler to yield a "representative" sample of resin. In order to obtain a single analytical result, 4 tests had to be performed: 21.. ASaPmFpOleebxltaenrnkal calibration sample 3. Polymer "control" (standard) sample 4. Process sample The original method specified use of 1.000 .001 grams of C-8 solution - extremely difficult to achieve for a methanol solution. Nonadecafluorodecanoic acid (C-10) was used as an internal standard. A "blank" (containing C-10) was tested to account for residual AfoPrFthOisiinmtphueriCty-1l0edsotoluatioconm. pAledxjussetriinegs tohfecaAlcPuFlOatiorenssp.onse for each sample to compensate The internal standard was originally used to account for differences in injection volume. With the acquisition of auto-injectors, variation in injection volume is small; however, an internal standard is still needed for this test. It is observed that the internal standard peaks aflrueordienparteedss(eCd-xin) etshteersprwesitehncthee opfolpyomlyemr seur.rfacTeh, iasndisappoosrstiibolny odfutheetoestienrteisrancotitoanvaoiflatbhlee for injection on the GC. The internal standard is used to adjust the sample response for incomplete recovery of the esters. The APFO peak is divided by the internal standard peak to yield a normalized response factor. The following components of the method were examined for possible simplification of the procedure as a way to improve cycle time and avoid introduction of error due to unnecessary steps: 1. Discontinuing use o f spuming riffler. 234.. DRReeispvclioasnecetcinaCul-ce1u0tlhawetioi"tnbhslaltenosksi"ntocsaxomircppoplreear.tfeluaocrtouhalepmtaanssoiocfaAciPdF(OC-u7s)e. d as an extermal standard. 5*. Replace the polymer control sample with statistical monitoring of the response of the APFO external calibration solution. Tproocceodmuprear(ePtrhoeceimdupraect1)ofartihdestehechraenvgiseesd, aprsoacmedpulereo (Procedure 2). tFeostuerdrhepy^licatems ewtheorde tested. Results are in Table SRP-1: '' Company Sanitized. Does not contain TSCA CBI Table SRP-1 : APFO content (ppm) average Procedure 1 0.9 0.6 0.9 1.1 0.9 Procedure 2 1.9 1.1 1.5 1.1 1.4 Procedure 2 shows slightly higher results; however, this difference is^onsidergfl acceptable fSaodervcoatwnntdoa,graeelsal soooffntfshe.estseFerirrcesystc,ulltethsteiamspppee,rcoleiafscischattothixoeincquilniomtteeirdtnfasolernstsraeitnsidivdaituryda,loafAn1PdpFspOtrmeafmorlitnheedmcaeltchuolda.t1io5DnPsu,Petmhtoechanges have been incorporated into WW-3690. To replace the polymer control sample, a response factor for the external calibration solution as follows: Factor = [(C8 peak/ C7 peak)/ mass used]. Part II: Determination of APFO in air samples: This procedure (WW-3627) has been used for several years for industrial hygiene mthoronuitgohrinagspoefcpiearlslyo-ntrneealteedxpToesnuarex.Atrpapo.rtaTblheepTuemnpaxis uissedthteondfrlauwshaedkninotwonavvoilaulm, aenodftahier eluted APFO is determined by GC-ECD. Historically, C-10 has been usecLas an mtc standard, and the tubes were individually treated with a mixture of reagents ir One objective of this study was to evaluate eliminating the use of die internal standard. rSeicnocveearyllosfatmheplCes-8aeresteters(tseede aasbocvleea).r sSoinlucteioanns,authtoe-rienjaercetonroissuusrefdac, eanidntearsaecrtiieosnsoftoexatefrfnecatl standards are run with each series of air samples, use of an internal standard is redundant. A second objective of this test was to compare a batch of tubes that were commercially treated by SKC to those prepared in B-3. The treated Tenax tubes were "spiked" with weighed amounts of a standard APFO solution (1 0 microgram/mL). ;A series of external standards were used as outlined in WW-3627. Twhaes GdiCvirdeesdpobnysethoef ecaalcchultautbeedwloaasdtihnegntuosecdaltcoulcaatlecuthlaetereacnoovbesryerveeffdicAiePnFcyO flooradeiancgh. tTubheis. Results are in Tables SRP-2 through 5. The average recovery for each set exceeds 100%. Company Sanitized. Does not contain TSCA CBI One factor is possibly the accuracy of the digital pipet used to deliver aliquots of standard APFO solutions for the calibration plots. Calibration plots prepared with C-10 internal standard (old procedure) and with no internal standard are shown in Figures SRP-1 and 2, respectively. Linearity is comparable and slightly better w/o C-10. Recoveries averaged 113% for the C-10 method vs. 111% with no internal standard. The results indicate that the internal standard is not needed. Comparable results were also noted between Tenax traps which had been prepared in B-3 vs. using traps that were pretreated by SKC. For the B-3 traps, average recovery was 113%. The tShKatCthtreapusseshoofwthede ainntearvnearal gsetarnedcaorvdebrye odfis1c1o0n%tin. uBedasaenddotnhtahtetsheerepsrue-lttsre, aitteids rTeecnoamxmetnrdaepds may be used for WW-3627. . Table SRP-2: APFO Recovery (%); C-10 Internal Standard tube ugadded ugfound %recovety 10-6 0.2469 0.2751 111 10-9 0.2021 0.2293 113 10-12 0.1790 0.2034! 114 10-21 0.2829 0.3194 113 10-24 0.1863 0.2025 109 10-27 0.1563 0.1841 118 10-30 0.1209 0.1371 113 average % recovery: 113 Table SRP-3: APFO Recovery (%); No Internal Standard -tube- -ug-added ug-fouRd %recovery 0-4 0.3016 0.34010 113 0-7 ; 0.3527 0.38485 109 0-10 0.4630 0.43338 94 0-13 0.1583 0.19637 124 0-15 0.1405 0.17720 126 0-19 0.2913 0.2979 102 0-22 0.2053 0.2063 100 0-25 0.1440 0.1601 111 0-28 ' 0.0930 0.1075 116 average % recovery: 111 Company Sanitized. Does not contain TSCA CBI Figure SRP-1: Calibration Plot (C-10 Internai Standard) Figure SRP-2: Calibration Plot (No Internai Standard) 35000 30000 0) 25000 oa 20000 (A (S 15000 o .10000 5000 0 0 y = 31399x + 818.14 R2 = 0.9978 0.2 0.4 0.6 0.8 uGAPFO 1 1.2 Company Sanitized. Does not contain TSCA CB! Table SRP-4: APFO Recovery (%); Tenax Prepared in B-3 tube 10-6 10-9 10-12 0-4 0-7 0-10 0-13 0-15 ugadded 0.2469 0.2021 0.1790 0.3016 0.3527 0.4630 0.1583 0.1405 ugfound 0.2751 0.2293 0.2034 0.34010 0.38485 0.43338 0.19637 0.17720 %recovery 111 113 114 113 109 94 124 126 average % 113 recovery: Table SRP-5: APFO Recovery (%); Tenax Prepared by SKC tube 10-21 10-24 10-27 10-30 0-19 0-22 0-25 0-28 ugadded 0.2829 0.1863 0.1563 0.1209 0.2913 0.2053 0.1440 0.0930 ugfound 0.3194 0.2025 0.1841 0.1371 0.2979 0.2063 0.1601 0.1075 %recovery 113 109 118 113 102 100 111 116 average % 110 recovery: Company Sanitized. Does not contain TSCA CBI Part III: Determination of APFO and Triton X-100 in aqueous media: In 2002, the determination of APFO in aqueous media at Washington Works was significantly unproved by the acquisition of an Agilent HPLC (Reference 1). The method requires minimal sample preparation and a 10-minute analysis time. We have begun receiving supemate and other aqueous samples for the simultaneous determination of APFO and Triton X-100. Both compounds give a UV response and can be analyzed by HPLC; however, the retention time for Triton is nearly 1 hour on our standard method (see Figure SRP-3). Altering the composition of the mobile phase led to a significantly shorter analysis time (see Figure SRP-4). A detailed comparison of the two HPLC methods is given in Table SRP-6. A 2 micron filter is used to remove polymer solids from the samples prior to injection. Figure SRP-3: Table SRP-6: HPLC Method Comparison Perchloric Acid (0.6%) 10 10 Mobile P lase Composition run time (%offl ow) Acetonitrile Water (min) -Retention Time (minutes) APFO Triton 40 50 90 6 V: ; . 53 50 40 20 3 12 Company Sanitized. Does not contain TSCA CB* m Figure SRP-4: Company Sanitized. Does no! contain TSCA CBf finished product APFO results.xls finished dispersion Company Sanitized. Does no! contain TSCA CBI 11/30/04 finished product APFO results.xls fine powder Company Sanitized. Does not contain TSCA CB1 11/30/04