Document dazV2Yemo6LLepQGR32gzZq4B

TO: TECHNICAL COMMUNICATIONS CENTER - 201-2CN (Importaiit - I f roport i s printed on bod, sides o f paper, send tw copies to rcc.) - - Divlslon IX k PC (Environmental Laboratory Bldg. 2-3E) - Prolect Fluorochemical 'Rnport Title Cmmerc i a 1 Chemicals P h o t o l y s i s of Fh13925 i n Aqueous S o l u t i o n s , To BACK TO MAIN NOV 1 3 1980 SECU'('TY ~ -_- ij KSYWORDS: (Select terms from 3 M Thesaurus. Suggest other Is Closed o Confide~ntial) ~ (Special~Authoriz~ation) y CURRENT OBJECTIVE: 3M C H E M I C A L R E G I S T R Y-- 1) Determine i f FM3925 i s degraded by photolysis and applicable terms.) identification of major products. I 2 ) Construct a three-chamber photoreactor and compare r e s u l t s w i t h a Crosby-Tang photoreactor. cc : A . Mezdel-2-3E-Y D. Ricker-53-4N REPORT ABSTRACT: (200-250words) This abstract i n f o r m tion is distributed by the Technical Communlcarions Center to alert 3M'urs to Company R&D. It is Company confidential meterial. Introduction: Object: Summzr y : E x p e r i m e n t a1 : 1. Sample m a t e r i a l s . 2 . Equipment : 1.. S i n g l e chamber p h o t o r e a c t o r . B. T r i p l e chamber photoreactor. C . Gas chromatograph. 3. Procedure : A . P r e p a r a t i o n and p h o t o l y s i s of FM3925 s o l u t i o n s . B. E x t r a c t i o n s : 1) Carbon f i l t e r . 2) X3925 s o l u t i o n s and blanks. 3) Solvent blanks. C. Analysis: 1) T h i n layer chromatography. 2 ) Ga,q chromatography. 3 ) Gas chromatography/mass s p e c t r o m e t r y . Xesulta and D i s c u s s i o n : Recommendation f o r Future Work: References: BACK TO MAIN Chtxinic;!li I troducecl i n t o t h e e n v i r o n m e n t may b e d e s t r o y e d o r p l i ~ t o l y t : ~ l y a l t e r e d by t h e a c t i o n o f s u n l i g h t . Consequently, o h o t o l y s i tuclies o n s u c h c h e m i c a l s a r e no!v r e q u j r c d b y t h e IJni tcd Stdrrs Rnvironmcntal P r o t e c t i o n Agency (EPri). Laboratory photorcactors produce predictable and reasonably constant irradiat i o n i n t e n s i t y and a r e n o t s u b j e c t t o t h e p e r t u r b a t i o n e f f e c t s of n a t u r a l s u n l i g h t . T h e C r o s b y a n d T a n g p h o t o r e a c t o r was s p e - i f - ic3lly designed to simulate sunlight photolysis and has been/is beicg used i n our laboratory f o r such studies.1 A variation of t h e C r o s b y a n d Tang p h o t o r e a c t o r , c o n s i s t i n g of 3 s t a c k a b l e i n d i v i d u a l s e c t i o n s , was d e s i g n e d t o a l l o w f o r s i m u l t a n e o u s p h o t o l y s i s oE a compound of i n t e r e s t , a r e f e r e n c e c o m p o u n d , a n d an actinometer. O- -b.-j.e-.c--t : `rtic o b j e c t of t h i s s t u d y was t o d e t e r m i n e i f FM-3925 was p h o t o l y z e d u n d e r l a b o r a t o r y c o n d i t i o n s . A s e c o n d e x p e r i m e n t was conducted t o compare t h e p h o t o l y s i s p r o d u c t s f r o m a t r i p l e v e r s u s s i n g l e chamber photoiysis unit. L,-inparison o f t h e photolyzed sample ( F i g u r e 7 ) w i t h t h e c o n t r o l sample ( F i g u r e 5 ) by e l e c t r o n c a p t u r e gas chromatography (EC/GC) showed no p h o t o l y s i s p r o d u c t s a f t e r 30 d a y s . Comparison of t h e a!>ove samples ( F i g u r e s 1 2 and 1 3 ) by f l a m e i o n i z a t i o n d e t e c t i o n ( ~ 1 1 1s )h o w e d two p o s s i b l e p h o t o l y s i s p r o d u c t s l a t e r i d e n t i f i e d b y q a s chromatography/mass s p e c t r o s c o p y (GC/MS) a s acetic a c i d , - n - ; > r o p y 1 a c e t a t e a n d / o r e t h a n o l . Repeat of t h e e x p e r i m e n t i n t h e chamber p h o t o l y s i s u n i t produced similar r e s u l t s by EC/GC no observable diEference. GC/MS identified two possible photolysis p r o d u c t s from t h e s e c o n d experiment a s a f l u o r o c a r b o n a m i n e and 'J-methylpcrf luorohexanesulfonamide (C6F12S02NCH3). ti Carbon filters on t h e photolysis u n i t s showed i n s i g n i f i c a n t a m o u n t s of FM-3925 was v o l a t i l i z e d d u r i n g t h e e x p e r i m e n t . The thrcc-chambcr p h o t o l y s i s u n i t w i l l be u s e f u l f o r p r e l i m i n a r y photolysis information whereas the preparative s i n g l e chamber u n i t w i l l , be u s e f u l f o r i s o l a t i n g and i d e n t i f y i n g p h o t o l y s i s p r o d u c t s , e s p e c i a l l y of compounds w i t h l o w water s o l u b i l i t y . E- -x .p_-e -r i-m- e n t-a-l : 1. S a i n ~ l cM a t e r i a l s : F'M - 3 9 2 5 is N -me t h y 1p e r f 1uo rooc t a r:e su 1Eon am j. de -N- e t h y 1a 1c o h o 1: BACK TO MAIN !?lbi- 3 9 2 5 P h o t o l y s i s - J!?G/CIIS I'aqc 3 tJovcmber 7 , 1380 A n a l y t i c a l s t a n d a r d - g r a d e m a t e r i a l 6 ( L o t 5 0 5 ) was o b t a i n e d from Don R i c k e r 0.f 3M Commercial C h e m i c a l s D i v i s i o n . C a l i b r a t i o n s t a n d a r d s a m p l e s f r o m 1 t o 50 ppm FM-3925 i n m e t h a n o l ( e t h y l a c e t a t e ) were p r e p a r e d b y v o l u m e t r i c d i l u t i o n of a 100-ppm s t a n d a r d ( 1 0 mg i n 1 0 0 m L o f m e t h a n o l ( e t h y l acetate)). D e i o n i z e d water was o b t a i n e d by p a s s i n g S t . P a u l c i t y w a t e r through beds o f a c t i v a t e d carbon, macroporous r e s i n , 2-mixed b e d d e i o n i z e r s , a 5 a n d 0 . 2 um f i l t e r . F i n a l r e s i s t i v i t y was g r e a t e r t h a n 18 megohms. C a r b o n f o r t r a p s was Witcarb g r a d e 9 5 0 , 8 x 30 mesh a v a i l a b l e f r o m Witco C h e m i c a l C o r p o r a t i o n , New Y o r k , N Y lOG17. Y e t h a n o l a n d d i c h l o r o m e t h a n e were r e a g e n t g r a d e w h i l e t h e e t h y l a c e t a t e was c h r o m a t o g r a p h y g r a d e I ( " L i C h r o s o 1 v " - a v a i l a b l e f r o m MC/B M a n u f a c t u r i n g C h e m i s t s , I n c . , Vorwood , 0'1 4 5 2 1 2 ) . T h i n - l a y e r c h r o m a t o g r a p h y (TLC) p l a t e s were s i l i c a g e l , w i t h 2 5 1 nm f l u o r e s c e n t i n d i c a t o r , p r e c o a t e d o n t o g l a s s p l a t e s t o a t h i c k n e s s o f 0 . 2 5 mm. P l a t e s a v a i l a b l e f r o m EM Laboratories, I n c . , 500 Executive Boulevard, Elmsford, NY 10523. 2. Tquipment: A., S i n g l e - c h a m b e r p h o t o r e a c t o r , F i g u r e 1, was t h a t o r i g i n a l l y described by Crosby and Tang2. D. T r i p l e - c h a m b e r p h o t o r e a c t o r , F i g u r e 2 , was a m o d i f i e d v e r s i o n ( o r i g i n s l l y described in 3 M T e c h n i c a l rJotcbook 52692-14) of t h e Crosby and Tang u n i t . C . G a s c h r o m a t o g r a p h s were a N e w l e t t - P a c k a r d (11-P) Model 5 7 1 3 ( e l e c t r o n c a Q t u r e ) a n d a n 11-P 5 7 5 0 ( f l a m e i o n i z a t i o n d e t e c t o r ) w i t h a !I-P 3380A i n t e g r a t o r - p r i n t e r . T h e a b o v e K are a v a i l a b l e from rlewlett-Packard Company, 150 Page M i l l Road, Palo Alto, C 4 94304. 3. Procedure: A . P r e p a r a t i o n and p h o t o l y s i s of FM-3925 s o l u t i o n s 4 s a t u r a t e d s o l u t i o n o f FM-3925 was p r e p a r e d by m a g n e t i c a l l y s t i r r i n g an e x c e s s o f t h e sample i n water for G h o u r s . The r e s u l t i n g solution was f i l t e r e d (Whatman-GF/F) and t h e clear f i l t r a t e used i n t h e Eollowing st-udies. BACK TO MAIN T h e s a t u r a t e d E'M-3925 s o l u t i o n was a d d e d t o the o h o t o l y s i s u n i t ( P i g u r e 1 ) a n d l a b a i r was b u b b l e d through the s o l u t i o n f o r 10 minutes.:\ A calcium chloride d r y i n g t u b e f i l l e d w i t h c a r b o n / g l a s s wool4 was t h e n n l a c e d ir, t h e a d d i t i o n p o r t . ':he t e m p e r a t u r e w a s m a i n t a i n e d a t 35'3C ( 9 5 O F ) b y p a s s i n g an a i r stream between t h e fluorescent. tube and i n s i d e waL1 oE t h e u n i t . T h e u n i t was t h e n w r a p p e d i n a l u m i n u m foil to minimize extraneous e f f e c t s . 4 q l a s s amber b o t t l e f i l l e d w i t h s a t u r a t e d FM-3925 s o l u t i o n f o r a c o n t r o l , was p l a c e d i n t h e d a r k a t room ,:f t e m p e r a t u r e . T h e e x p e r i m e n t was r u n f o r 30 d a y s . 1 The a b o v e p r o c e d u r e was u s e d f o r t h e t r i p l e chamber ( F i g u r e 2 ) u n i t w i t h t h e following v a r i a t i o n s : 1) Chamber 1 ( t . o p ) f i l l e d w i t h w a t e r , c h a m b e r 2 was e m p t y , a n d t h e bottom c h a m b e r C i l l e d w i t h t h e FM-3925 s o l u t i o n : 2 ) t e m p e r a t u r e was m ( 2 i n t a i n e d a t 21+3OC (70+50F) b y p a s s i n g w a t e r t h r o u g h i a t e x t u b i n g -(3,/16" i . d . , 3/32" w a l l ) t h a t was w r a p p e d a r o u n d t h e o u t s i d e of p h o t o l y s i s unit. 8. E x t r a c t i o n 1. Carbon T h e c a r b o n f r o m t h e calcium c h l o r i d e t r a p s was S o x h l e t e x t r a c t e d (1 c y c l e s per 30 m i n u t e s ) f o r 5 h o u r s w i t h d i c h l o r o m e t h a n e ( C H 2 C 1 2 ) . T h e e x t r a c t was t h e n c o n c e n t r a t e d t o 1 . 0 rnL w i t h a K u d e r n a - D a n i s h (K-D) c o n c e n t r a t o r . A p p r o x i m a t e l y 10 m L of methanol was added a n d s a m p l e r e c o n c e n t r a t e d t o 1 . 0 m L i n t h e Y-D. The c a r b o n w a s t h e n r e - e x t r a c t e d (1 c y c l e s f o r 30 minutes) w i t h methanol f o r 5 hours and t h e :nethanoL e x t r a c t c o n c e n t r a t e d t o 1 . 0 mL w i t h t h e K-D concentrator. 2 . FM-3925 ( p h o t o l y z e d a n d c o n t r o l l e d ) a n d water b l a n k . L O O mL of s o l u t i o n was p i p e t t e d i n t o a 250-mL s e p a r a t o r y f u n n e l . S a m 2 l e was e x t r a r t e d 3 times ( 1 5 , 5 , 5 mL) w i t h e t h y l acetate ( E t O A c ) . The extracts were a d d e d t o a 25-mL v o l u m e t r i c f l a s k a n d d i l u t e d t o mark with e t h y l acetate. $ For t h e s e c o n d e x p e r i m e n t , t h e a q u e o u s s a m p l e s were e x t r a c t e d 3 times (10,1C,5 mL) w i t h d i c h l o r o m e t h a n e . T h e e x t r a c t s were c o m b i n e d a n d c o n c e n t r a t e d t o 1 . 5 mL w i t h the K-D c o n c e n t r a t o r and t h e n d i l u t e d t o mark w i t h m e t h a n o l i n a 2 5 mL v o l u m e t r i c f l a s k . BACK TO MAIN '1. S o l v e n t blanks A p p r o p r i a t p s o 1 . v e n t b l a n k s were p r e p a r e d by t a k i n g s o l v e n t s , e - u i v a l e n t a m o u n t s ,ss in. above e x t r a c t i o n s , a n d s u b j e c t i n g t o t h e szme c o n c e n t r a t i o n s c h e m e s . r.:. A n a l y s i s 1. T h i n - l a y e r c h r o m a t o g r a p h y ( T L C ) : P l a t e s were p r e d e v e l o p e d w i t h methanol. a n d s a m p l e s were c h r o m a t o g r a p h e d i n p a p e r - l i n e d g l a s s t a n k s u s i n g 95/5 e t h y l acetate/ethanol as t h e solvent. V i s u a l i z a t i o n was w i t h [Jew F u c h s i n 5 (0.058 a q u e a u s s o l u t i o n ) or Rhodamine 6 G . 2 . Gas c h r o m a t o g r a p h y (GC): E l e c t r o n c a p t u r e ( EC)-fJiG3-an:3 lame i.onixation t d e t e c t i o n ( F I D ) was e m p l o y e d for a n a l y s i s of a l l samples. A s i x - f e e t , 1/8 inch o d , stainless steel c o l u m n p a c k e d w i t h 1 0 % CW20M o n 6 0 / 8 0 mesh C h r o m a s o r b w-,\W was u s e d . I n j e c t i o n ( 5 t i l ) was o n - c o l u n n a t 2 0 0 3 C w i t h d e t e c t i o n p o r t a t :300C. C a r r i e r f l o w was 95.5 4rgon/Yethan? ('le for FIl)) a t - 4 0 c c / m i n u t e . Two t e m p e r a t u r e p r o g r a m s were u s e d : 1 ) 180OC i s o t h e r m a l ; 2 ) 165OC i n i t i a l ( w i t h a 16 minute h o l d ) t h e n t o 235OC a t a r a t e of 8 C / m i n u t e w i t h a n u p p e r l i m i t h o l d so t o t a i run time wi.s 1 hour. 3 . Cas chroinatogranhy/'mass spectroscopy (GC/MS) : 4 E t e r o p t i m i z i n g GC c o n d i t i o n s sample c o n c e n t r a t e s were s u b m i t t e d t o C e n t r a l Research Lab (Joe Schroepfer) for GC/XS identification. $ R- e -s -u -l -t -s.-a-n-d- -D--i-s-c-u-s-s-i-o_n: P r e L i i n i n a r y T L C i n d i c a t e d f o u r s p o t s ( R F =: 0 . 0 6 , 0.20, 0.64, 0.76) w i t h Mew F u c h s i n i n b o t h t h e c o n t r ~ l .a n d p h o t o l y z e d s a m F l e s w h i l e R h o d a m i n e 6G d e t e c t e d o n l y o n e s p o t ( R F = 0 . 7 6 ) i n t h e same ssin?lcs. 'Jew F u c h s i n and Rhodamine 6G i n d i c a t e d o n l y o n e s p o t ( R F = 0 . 5 7 ) f o r t h e FM-3325 s t a n d a r d . A d d i t i o n a l TLC on e t h y l a c e t a t e e x t r a c t s of w a t e r , FY-392.5 ( c o n t r o l , p h o t o l y z e d s a m p l e , and s t a n d a r d ) , and a b l a n k i n d i c a t e d t h e spot a t RF = 0.76 t o be an impurity i n the etliyl acetate. $lore d e t a i l e d work b y GC showed m e t h a n o l as t h e o n l y s o l v e n t c o n t a i n i n g a n i m n u r i t y ( F i g u r e s 3 , 4 , a n d 11). A m e t h y l e n e c h l o r i d e e x t r a c t e d w a t e r b l a n k ( F i g u r e 1 0 ) showed no i m p u r i t i e s . c;c s h o w s 7 8 % of t h e Fq-3325 t o be u n r e a c t i v e o v e r a 3 0 - d a y p e r i o d (Table 1). i BACK TO MAIN Y l e c t r o n C a p t u r e GC R e s u l t s of FM-3325 ? h o t o l y s i s le()II !I I n n k !; t 0 A c 13 1a nk I-"l-3935 C o n t r o l 174-3925 S t d . 17Y- 3 32 5 P h o t o l y z e d C;lcbon f i l t e r Ci17C12 e x t r a c t PleijiI e x t r a c t PJll* 3 IJ D 4 4.9 5 15.7 6 3.8 7 0 . 1 pg/g c a r b o n I3 ND I) * r J r ) = Not d e t e c t e d . L I.,' l i c 2 2 % Loss is e i t h e r c a u s e d by v o l a t i l i z a t i o n ( n o t d e t e c t e d i n I t the! c a r b o n t r a p ) 3.1 Eormation of s i m i l a r p r o d u c t - s i n l a r g e q r i n n t i t i e s a s i n t h e c o n t r o l ( F i g u r e s 5, 1 2 ) , 3 ) s o r p t i o n of Fxl-3925, or d e g r a d a t i v e p r o d u c t s , a n t o t h e w = , l l s o f t h e p h o t o l y s i s u n i t , 4 ) f o r m a t i o n of c o m p o u n d s ( e . g . , FC-35 Cf3F17SO3fl), which c a n n o t be a n a l y z e d by GC. TLC d i d not detect IT-95 i n t h e p h o t o l y z e d s a m p l e i n d i c a t i n g t h a t i f f o r m e d i t was present i n very small q u a n t i t i e s . The comFounds p r e s e n t i n the p!iotolyzed s a r q l e were a l s o p r e s e n t i n t h e c o n t r o l i n d i c a t i n g ~ l e g r a d a t i o no t h e r t h a n p h o t o l y s i s i s o c c u r r i n g G . GC ( F I D ) s h o w s a n e n r i c h m e n t of t h e e a r l y peak ( T R = 6 . 2 m i n u t e s ) w i t h almost c o i n p l e t e l o s s of t h e l a t e e l u t i n g pea.X ( T n = 8 . 3 inint&tes) when com2ared t o t h e FY-3925 s t a n d a r d I' t r i p l e t " ( F i g u r e s 12 h 14). n latt? e l u t i n g peak (by E&C) tentatively identified ( b y GC/YS) 3 s o c t y l s u l f o n y l f l u o r i d c , OSF, (CgF17S02F) was present i n t h e c o n t r o l a n d p h o t o l y z e d s a m D l c t s . F u r t h e r w o r k i n d i c a t e d OSF formed r a p i d l y i n aqueous s o l u t i o n s . T h e p r e s e n c e o f C>SF c o u l d Lie a r a n i d h y d r o l y s i s p r o d u c t o r a v e r y w a t e r s o l u b l e i m p u r i t y 6 i n the standard. Sample work-up ( s o l v e n t i n t e r a c t i o n s or thermal d e g r a d a t i o n ) was shown t o be a n u n l i k e l y c a u s e f o r f o r m a t i o n o f OSF. '4ct'nylene c h l o r i d e e x t r a c t s of t h e carbo:> f i l t e r showed a small a m o u n t of FY-3925 ( T a b l e 1 , F i g c r e 8 1 , w i t h n o o t h e r major peaks o r e s e n t . FM-3925 was n o t p r e s e n t i n t k e m e t h a n o l e x t r a c t e d c a r b o n b u t a l a t e e l u t i n g p e a k (TR = 6 . 6 m i n u t e s , F i g u r e 9 ) was detected b u t n o t i d e n t i f i e d . Small a m o u n t s of t h i s l a t e e l u t e r ! were p r e s e n t i n t h e m e t h y l e n e c h l o r i d e e x t r a c t e d c a r b o n 1 p h o t o l y z e d a n d c o n t r o l s a m p l e s . S i n c e FM-3925 was n o t p r e s e n t i n j thc methanol extracted carbon, methylene c h l o r i d e e x t r a c t i o n is s u f Eicient. for d e t e r m i n i n g l o s s o f FM-3925 f r o m s o l u t i o n . BACK TO MAIN 1 ) n e t c r m i n a t i o n o f o r i g i n a n d i d e n t i f i c a t i o n of l a t e e l u t i n g ;)cak i n t h e met'hano1 e x t r a c t e d c a r b o n . 2 ) Cause t h e a p p a r e n t e n r i c h m e n t of t h e e a r l y e l u t i n g Deak i n thc FV-.3325 " t r i p l e t " a n d loss of t h e Late e l u t e r . 3 ) More d e t a i l e d i d c n t i i c a t i o n of p r o d u c t s f o r m e d i n t h e control sample. 4 ) D e t e r m i n a t i o n of e x a c t c a u s e of f o r m a t i o n of $:)SF. 5 ) Determine i f h y d r o l y s i s p l a y s a l a r g e r r o l e i n d e g r a d a t i o n than photolysis. . I:, !JGTES R N D REFERENCES 1. Technical Report Summary "Evaluation of a Laboratory P h o t o r e a c t o r f o r S i m u l a t i n g S u n l i g h t P h o t o l y s e s , 'I b y J e r r y W . T o d d , 2 0 J u l y 1 9 7 9 . Deet. 31)68, PN 9 7 7 6 7 5 0 2 0 2 , R e p o r t #3. - _ _ 2 . C r o s b y , D. G . a n d T a n g , C . S . , J . AAric. F o o d Chem., ( 1 9 6 9 ) __I_---I----1-7 , 1 0 4 1 . 3 . P r i v a t e c o n v e r s a t i o n of A . Yer?del w i t h 11. G . Zepp of t h e U.S. ?PA, Athens, GA. 4. The carbon t r a p would collect volatile compounds l e a v i n g t h e t e s t solution. T h e s e compounds c o u l d t h e n be d e s o r b e d and quantitated. - / 5 . 1 < w a p n i c w s k i 2.: C i c h o n , R. -Y--i--c-r o c h e-_m--i-c a l J o u-r-n-a--! ( 1 9 7 9 ) 2-4._, . , 290-299. j/ 6. F"I-3925 is a n i x t u r e of a t l e a s t three coiiponents, v a r y i n y i n branching and/or chain length. 7 . C. '1. S c h r a n d t h a s t r a n s f e r r e d t o A u t o T r a d e s , D l d g , 251-212. i.i~ure1 - .Laboratory k h o t o r e a c t o r BACK TO MAIN Add i t i on port Gas InlPt wlth Teflon 0 +/ tubing and glass bubbler r Thermometer we 1 1 , / ePnyvree1xope F-~OBL / fluorescent tube i' I Ffgure 2 T r ip le Chamb.?r Hod 1 f 1ed C rosby-? ang Photoreac t o r BACK TO MAIN a s i n l e t w i t h Tef 1 on8 u b i n g and g l a s s b#ubSler 24/40 3 A d d i t i o n port Thermmet e r we1 1 Drain L t F-4OBL fluorescent tube Pyrex glass enve 1ope Spacer . .-, -I -* rl i . . i i Ii ! i -. i i j i -. I I 1 i I 1 J BACK TO MAIN FIGURE 3 BACK TO MAIN = wl 7 Fouee 4 Ethyl Acetate Bleak re Eveermen Carmure 2 | noc FLGUQE s BACK TO MAIN t- u W c7. w lx s 'S w ry U '. 'i BACK TO MAIN ,-.: I I- . FIGURE6 " --- i.1 '3 t M b- t BACK TO MAIN t- u ... u c. (0 4 'D W a: x a W Iy II I 4 BACK TO MAIN ! I I I I \ ! i I i ! I C. 'Q W L BACK TO MAIN 1 `1 I N a w CY Q: 10 old d BACK TO MAIN I ! 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