Reactions of chlorine dioxide with hydrocarbons - ACS Publications

water are being sought; chlorine dioxide (C102) is one disinfectant that has receivedconsiderable attention as an alternative disinfectant to chlorine...
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Environ. Sci. Technol. 1982, 16, 268-273 X 148 mm, 24X reduction, negatives) may be obtained from Distribution Office, Books and Journals Division, American Chemical Society, 1155 16th St., N.W., Washington, D.C. 20036. Full bibliographic citation (journal, title of article, author) and prepayment, check or money order for $3.00 for photocopy ($4.50 foreign) or $4.00 for microfiche ($5.00 foreign), are required.

Literature Cited Fed. Regist. 1979, 44, 69 464-69 575. Riggin, R. M.; Howard, C. C. Anal. Chem. 1979,51,210-214. Fed. Regist. 1974. 39. 3756-3797. Perry, 6. L.; Chuang; C. C.; Jungclaus, G. A.; Warner, J.

S. Battelle Columbus Labs, Columbus, OH, February 1979, NITS PB-294 794, p 3.

(5) Ogan, K.; Katz, E.; Slavin, W. J . Chromatogr. Sei. 1978, 16, 517-522. (6) Koch, D. D.; Kissinger, P. T. Life Sci. 1980,26,1099-1107. (7) Bratin, K.; King, W. P.; Kissinger, P. T.; Rice, J. R. In

“Recent Advances in Pesticide Analytical Methodology”; Harvey, J. C., Ed.; American Chemical Society: Washington, D.C., 1980, ACS Symp. Ser. No. 136, Chapter 5. (8) Miner, D. J.;Rice, J. R.; Riggin, R. M.; Kissinger, P. T. Anal. Chem. 1981,53, 2258-2263. (9) Davis, G. C.; Kissinger, P. T. Anal. Chem. 1979, 51, 1960-1965. Received for review June 8,1981. Revised manuscript received October 26, 1981. Accepted January 12, 1982.

Reactions of Chlorine Dioxide with Hydrocarbons: Effects of Activated Carbon Abraham S. C. Chen, Rlchard A. Larson, and Vernon L. Snoeylnk”

Department of Civil Engineering, University of Illinois, Urbana, Illinois 6 1801 Chlorine dioxide was shown to react rapidly with one group of easily oxidized hydrocarbons in dilute (ca. 0.5 mg/L, 5 X lo4 M) aqueous solution. Hydrocarbons with benzylic hydrogen atoms (ethylbenzene, indan, Tetralin, diphenylmethane, and fluorene) reacted, probably by radical pathways, to give oxidized derivatives such as ketones and (sometimes) alcohols at the benzylic positions. In the presence of activated-carbon columns, additional products were formed under some conditions. When a hydrocarbon was allowed to react with chlorine dioxide in aqueous solution for 2.9 min at pH 3.5 and the reaction mixture was passed over a bed of HD3000 granular activated carbon, monochloro and/or dichloro derivatives were produced in addition to the oxygenated compounds observed in the absence of the carbon. W

Introduction Chlorination, as normally practiced in water and waste-water treatment, results in the formation of trihalomethanes and other chlorinated organic compounds which may be undesirable from the viewpoint of waterpollution control and human health. Accordingly, alternatives to chlorine for the disinfection of water and waste water are being sought; chlorine dioxide (C102) is one disinfectant that has received considerable attention as an alternative disinfectant to chlorine. Activated carbon has been used effectively for the removal of trace organic contaminants in water supply. Should chlorine dioxide be used as a disinfectant, it would react with some organic compounds in water and come into contact with activated carbon in the treatment processes (1). It is important to ascertain that potentially toxic organic compounds will not be formed in chlorine dioxide treated water or on the activated-carbon surface and eventually pass into the effluent from the activated-carbon bed. The end products from the treatment processes therefore need to be carefully examined. The reactions of chlorine dioxide with most of the organic compound types frequently found in water have not been thoroughly studied. Most of the work reported so far has been done with tertiary amines ( 2 , 3 )and phenols (4-6); there are a few reports on its reactions with olefins (7-9). Its oxidative reactivity toward alcohols and aldeh268

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ydes (to form the corresponding carboxylic acids) appears to be greater than that of aqueous chlorine (10). Chlorine dioxide does not react with saturated aliphatic hydrocarbons and aliphatic side chains (11),but the latter may be split from aromatic rings or other functional groups (12). The chlorination of aromatic and unsaturated aliphatic hydrocarbons by chlorine dioxide has been reported by some researchers (7,10,12,14,15). No trihalomethanes have been detected as reaction products of chlorine dioxide with organic materials (11,12, 16-18). There is no information available to date on the reaction of chlorine dioxide with activated carbon, although granular activated carbon (GAC) has been known to react readily with free chlorine (HOC1and OCl-) to produce C1(19) and to react much more slowly with monochloramine (20). During the reaction with free chlorine, suface changes have been reported (21-23). In addition, a high molecular weight colored product as well as some smaller chlorinated organic molecules and aromatic hydrocarbons are obtained under harsh conditions (2.5 g as C12/gof GAC) of reaction of free chlorine with bituminous-based activated carbon (1). It is not known, however, if chlorine dioxide will produce similar materials from activated carbon. Most investigations of organic compounds in the presence of activated carbons have been determinations of their adsorptive properties. Very few studies have been done on the role of activated carbon in the reaction of sorbed organic compounds. (A few reports concerning activated-carbon-catalyzed reactions include oxidation of oxalic acid to COz (24) and conversion of n-butylmercaptan to dibutyl disulfide (25).) Recently, McCreary and Snoeyink (26)and McCreary (27) observed that GAC, in the presence of free chlorine, promoted the formation of new products that were not observed in solution. The mechanistic role of GAC in these reactions was not determined; oxygen-containing functional groups or metals on the surface may have played roles (24,25,28). This study was therefore designed to characterize the products of the reactions between aqueous chlorine dioxide and some selected hydrocarbons either contained in aqueous solution or adsorbed on an activated-carbon surface. Chlorine dioxide tends to disproportionate into chlorite (C102-) and chlorate (C103-) in alkaline solution (24-31), but no appropriate analytical techniques are

0013-936X/82/0916-0268$01.25/0

0 1982 American Chemical Society

available for accurate measurements of low concentrations of these anionic species in the presence of chlorine dioxide (32). Thus, the study was confined to mildly acid or neutral pHs. Materials and Methods Materials. Several organic hydrocarbons having benzylic hydrogen atoms (including ethylbenzene, indan, Tetralin, diphenylmethane, and fluorene) were selected for preliminary experiments because of their rapid reaction with other radical species. The compounds used were purified, if necessary. Diphenylmethane, for example, was purified by repeated recrystallizations from ethanol and hexane. The hydrocarbon stock solutions were prepared in tert-butyl alcohol or water [with use of Mackay and Shiu's procedure ( 3 3 ) ] . The dilute aqueous solutions of the hydrocarbons were buffered with 0.01 M phosphate if a solution pH of 5.3 or higher was desired. The solution bottles were covered with dark plastic and sealed with aluminum caps. A stock solution of chlorine dioxide was prepared daily by generating chlorine dioxide gas from NaC102 and K2S208 followed by dissolving the evolved gas in chilled distilled and deionized water (34). Its dilute aqueous SOlution was made by adding an appropriate amount of stock solution into distilled and deionized water that either contained a 0.01 M phosphate buffer or was left unbuffered (for pH 3.5). The chlorine dioxide concentration was measured by the DPD titrimetric procedure (35). After chlorine dioxide was stripped out of the solution, its purity was evaluated by the DPD procedure (showing that free chlorine and chlorite were absent) and the acid o-tolidine method (showing that chlorate was also absent) (36).The solution prepared, in fact, was free of free chlorine, chlorite, and chlorate, A t room temperature, the chlorine dioxide concentration decreased almost 13% a t pH 3.5 in 2 days if the solution was well-covered from light. The carbons used in the experiments were HD3000 (IC1 America Inc., Wilmington, DE) and F400 (Calgon Corp., Philadelphia, PA). The GAC's were prepared by sieving to the desired size fraction, washing, drying, and baking at 175 OC for a week. Chlorine Dioxide-Activated Carbon Reaction. Batch tests were used to determine volatile compounds and total organic halogen (TOX) in water. High concentrations M ClOJ of (95-400 mg/L of C102, ca. 1.4-5.9 X chlorine dioxide with various ratios of activated carbon was placed into 120-mL headspace-free, Teflon-covered bottles sealed with aluminum caps. Some bottles had no carbon and served as blanks. After different periods of time in a rotary shaker, the remaining chlorine dioxide was reduced with sodium sulfite, and solutions were analyzed immediately for volatile compounds by using the purgeand-trap procedure as described by Snoeyink et al. (I). TOX in water was determined by the Dohrmann microcoulometric titration system (MCTS-20 including a S-300 pyrolysis furnace, a C-300 digital microcoulometer, and a T 3 0 0 4 titration cell) equipped with TOX-1 adsorption module (Dohrmann Co., Santa Clara, CAI. Column tests using GAC secured between Pyrex wool in glass columns of 1.9-cm i.d. were used to examine TOX buildup and the formation of solvent-extractable compounds on its surface. A column containing 48.1 g of 30 X 40 mesh HD3000 GAC received a 3.8 mg/L chlorine dioxide solution (pH 3.5) at hydraulic loading of 2.97 m/h. A control column received a sulfite-quenched solution (initial CIOz concentration 3.8 mg/L) under similar conditions. The sulfite-quenched solution contained chloride and chlorate but not chlorite. A t the conclusion of the

runs, samples of GAC were processed as deshribed by McCreary and Snoeyink (26) for TOX analyses; TOX measurements were made mainly with the Dohrmann MCTS-20 system. Additionally, 1-2-g samples of GAC were centrifuged, Soxhlet extracted, and concentrhted as described by Snoeyink et al. (I). Anthracene wag added to the extracts as an internal standard. The extracts were derivatized, if necessary, with diazomethane, and 2 fiL of the concentrate was injected into a 20-m $P-2160 @ ~ 8 or fused-silica capillary column (Hewlett-Packad 6890 CC or 5985 A GC/MS system). The column w&s ptOgr!anhled from 20 OC with a 5-min hold to 240 "C a t 2 O? 8 'C/min. The compounds were identified by comparkon b, coniputer-accessible or published reference sp&tra (37-39). Chlorine Dioxide-Hydr&boa Reaktibn, Chlotbe dioxide in dilute aqueous solution (a. 3-8 mg/L of c101, 4.5-9 x M ClOJ reacted with vatfoub h~dMWbobs (0.5 mg/L, ca. 5 X lo* M) individudy &t different periods of time. At the end of &e ttsi sodium sulfite was applied into the batch r&ctbt& "'he 10-L reaction mixture was acidified and oCer purified XAD-2 resin as described by McCreaty and t h e y ink (26). Indan was allowed to react with chlorine dioxide at the additional pHs of 5.3 and 7.0, and the $ d ~ t i O W &~t extracted with F400 and HD3000 GAC as well Bb %4D-2. The aqueous extracts were concentrated, derivathd (when necessary), and analyzed by GC and GC/mass spdctrornetry as described above. Laboratory Column Studiee. The laboHto@ GAC column assembly for chlorine dioxide adsotbed hydrccarbon studies was constructed of glass, Teflon, And stainless steel. The carbon beds (HD3000, X 60 U.S. standard mesh) were secured between pyfi!x drboI plugs in 1.9-cm i.d. glass columns. Chlorine diotidd dhd hydrocarbon solutions were individually pumped thfoclgh the columns by using a stainless-steel T-Swagelok uniori. A reaction time of 2.9 min was allowed befoh3 tb& m i l h e entered the carbon bed. The columns he& f\th at I hydraulic loading rate of 4.6 m/h for 3 ddys bfo* &&)le$ of carbon were taken for Soxhlet extractfan a d & or GC/mass spectrometry analysis.

a

Results and Discussion Chlorine Dioxide-Hydrocarbon Reactibn. Hydrocarbons with benzylic hydrogen atoms rapidly reacted WI chlorine dioxide in dilute aqueous solution (molar ratio C102/hydrocarbon about 1O:l). The reaction took place so rapidly that comparable reaction products were o b tainable from reaction periods of 2.9 min a d 2 days. The reaction products are listed in Tables I (at pH 3.5)and 11 (indan a t pH 3.5, 5.3, and 7.0). The oxidized derivatives such as benzylic ketones and alcohols were the majot products from the reaction. Since chlorine dioxide h& ari unpaired electron and exists entirely or almost entirely tu a permanent free-radical monomer (2), th? Mction mechanism for the formation of benzylic ketones must involve free radicals. Ethylbenzene, for bkatiiple, is probably attacked by chlorine dioxide at its cy @t&h d converted to a benzylic radical (I) by h y d r w n a&&ct;bn. Acetophenone is probably formed via the radical I ACcording to the reaction sequence s h o w in eq i, Other oclol(H

(I)

benzylic ketones including a-tetralone, benzophehone, fluorenone, and a-indanone (from the corresponding Environ. Sci. Technol., Vol. 16, No. 5 , 1982 269

Table I. Chlorine Dioxide-Hydrocarbon Reactions a t pH 3.5 compound ethylbenzene ethylbenzeneC acetophenone a-methylbenzyl alcohol methyl 2-(or 3-)chlorobenzoate a-phenylethyl etherd Tetralin cis-decaline truns-decaline tetralinC naphthalenee 1,2-dihydronaphthalene 0-(0-hydroxy phenyl)-

p& 08 +E

a2

++z++

mol wt

aq solna

GAC extractb

106 120 122 170

+

+

t f

+f

+ + :a + +

+ +

++ ++

226 138 138 132 128 130 166

+ + + +

Px

++

aJ

+

+++

t

+

+ +

trace

?

propionic acid a -tetralone

a-tetralol a -naphthoquinone hydroxy-1-tetralone or hydroxy coumarin a-tetralone, monochloro der a-tetralol, monochloro der tetralin, dichloro der B-(0-carboxypheny1)propionic acid methyl ester a -Tetralone naphthalenee a-tetralonee a-naphthoquinone hydroxy-1-tetralone or hydroxycoumarin tetrahydronaphthalene-1,4(or -1,2-) dione diphenylmethane benzaldehyde biphenyl diphenylmethaneC (2-methylpheny1)phenylmethanee (4-methylpheny1)phenylme thanee

146 148 158 162

+f

+ +

160

t

+f

+

180 182 200 222

128 146 158 162

t f

+

+

trace

+

+ +

Y

l

a

o m

+f

9 'E % x

t t f

ug

BO 106 154 168 182 182

+f

+ + + +

+ +

$5 Px

++ + aJ

++z+t++++

+ +

198 trace + phenylmethane +f 182 t f benzophenone + 226 a-phenylethyl etherd + 20 2 (chloropheny1)phenylmethane 184 + t f benzhydrol 198 + o-hydrox ybenzophenone 196 + + p-methylbenzophenoneg fluorene 168 + dibenzofurane t fluoreneC 166 t 168 + + diphenylmethanee t 182 + a-fluorenol ? 196 meth yl-a-fluorenol + 180 + f a-fluorenone + 200 chlorofluorene a XAD-2 extracts of aqueous solutions reacted for 2.9 Soxhlet extraction of 2 g of GAC min, 1 h, and 2 days. receiving a reaction mixture of chlorine dioxide and hydrocarbon reacted for 2.9 min. Startin material. From ClO,-GAC reaction. e Impurity. Major product. g Reaction product of impurity. (( rn-hydroxymethy1)phenyl)-

B

starting materials of Tetralin, diphenylmethane, fluorene, and indan) are likely to be produced by an identical mechanism. Similar radical pathways were previously suggested by Lindgren et al. for the formation of an allylic 270

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aJ

c

?

ketone (cyclohex-1-en-3-one)from cyclohexene (7). The chlorine dioxide dose and the hydrocarbon concentration in these studies, however, were about 2-5 orders of magnitude higher than those in this study; also, aqueous suspensions (rather than solutions) of cyclohexene were used. Benzylic alcohols (a-tetralol, benzhydrol, a-fluorenol, and a-indanol) were probably formed by hydrolysis of the intermediate chlorite esters as shown by eq 2.

I

/

t

/ '

o*@-p)

(222 0

(2)

OH

In addition to the ketone and alcohol, biphenyl and benzaldehyde were also found in the XAD-2 extract of the chlorine dioxidediphenylmethe reaction. Biphenyl may have been formed by decarbonylation of benzophenone (40);benzaldehyde might be formed from an intermediate diphenylmethane hydroperoxide (41). Other than a-tetralone and a-tetralol, compounds such as 1,6naphthoquinone, hydroxy-1-tetralone (or hydroxycoumarin), and @-(0-hydroxypheny1)propionicacid were also identified from the tetralin-chlorine dioxide reaction. A separate batch experiment was carried out with a-tetralone and chlorine dioxide as starting materials. The GC/mass spectrometry analyses showed that both 1,4naphthoquinone and hydroxy-1-tetralone (or hydroxycoumarin) together with tetrahydronaphthalene-1,4-(or -1,2-) dione were major oxidized products from a-tetralone. a-Tetralone may have been attacked by chlorine dioxide at its benzylic 4 position and oxidized to a 1,4-diketone by radical pathways, or it may have formed an intermediate hydroperoxide at either its 4 or 2 position (41). The hydroperoxide could (i) dehydrate to a 1,4- (or 1,2-) diketone, (ii) break down to diketone and hydroxy-1-tetralone, or (iii) undergo a more complex decomposition leading to carbon-carbon bond fission (41). (0-(0-Carboxypheny1)propionic acid methyl ester has been identified as a product of the reaction between tetralin adsorbed on carbon and chlorine dioxide.) A generalized reaction scheme for the tetralin-chlorine dioxide reaction is shown in Figure 1. Indan also reacted with chlorine dioxide at pH 3.5 to produce a diketone, a hydroxyindanone, and indan-1,3-diol. At higher pHs (5.3 or neutral), however, these compounds were not formed; a-indanone and sometimes a-indanol were produced (but at a considerably slower rate). Chlorine DioxideAdsorbed Hydrocarbon Reaction. When hydrocarbons were allowed to react with chlorine dioxide in aqueous solution for 2.9 min at pH 3.5 and the reaction mixture was passed over a HD3000 GAC bed, compounds other than the oxygenated derivatives were identified in the GAC extract. Chlorinated compounds were found uniquely in carbon surface reactions (Tables I and 11). The formation of chloroindan from the reaction between chlorine dioxide and indan in the presence of GAC strongly suggests a contribution of radical processes. For example, indan, possibly in a metal ion catalyzed process, might be converted at the carbon surface to the stable benzylic 1-indanyl radical. This species would react readily with other odd-electron species such as Cl., if present, to give 1-chloroindan directly. In the chlorine dioxide reactions done at pH 7.0, no chloroindan was observed (see Table 11), suggesting a possible role for molecular chlorine

0

OH

Figure 1. Generalized reaction pathway for Tetralin-chlorine dioxide reaction.

(which could be generated by acid hydrolysis of intermediate chlorite esters to HOC1 or by other routes involving the carbon surface) (see eq 3).

(3)

CI

05

( W l t h C Present)

Monochloro-a-tetralone could be produced from 1,2dihydronaphthalene; chlorine dioxide might add to the double bond of 1,2-dihydronaphthalene to give a radical such as I1 (see eq 4). 2-Chlorotetralone could be produced

(11)

&c'(Wlth

(4)

C Present)

from I1 by losing HClO and adding an odd-electron species, C1-. Alternatively, hypochlorous acid (HOC11 might add across the double bond of 1,2-dihydronaphthalene to produce a chlorohydrin, followed by oxidation of the alcohol to ketone by chlorine dioxide. As shown in Tables I and 11,both chlorotetralol and chloroindanolwere found in the corresponding carbon extracts, but no chloroindanone was identified. At pH 3.5 both a dichloroindan and a dichlorotetralin were formed. However, at pH 5.3 and 7.0, no dichloro derivatives were found; this again suggests a possible role for molecular chlorine in the reactions, possibly by simple addition of Clz to the double bond of indene or 1,2-dihydronaphthalene. In order to eliminate the possibility that the new compounds formed on the carbon surfaces were simply a result of different extraction methods, sorbents other than XAD-2 resin, including HD3000 and F400 GAC, were used to extract the same amount of water (pH 3.5, 5.3, or 7.0) in which a mixture of indan and chlorine dioxide had Environ. Sci. Technol., Voi. 16, No. 5, 1982

271

2

i

I

I

I

I

I

to C102 Column A Control Column

(i) 89 2

Fi

89

(iii) Figure 2. Total-Ion-current chromatograms of (I) the eluate of XAD-2 resin and of the Soxhlet extracts of (il) HD 3000 and (iii) F 400 GAC from indan-CIO, aqueous solutions at pH 3.5. The numbered peaks correspond to the compounds Identified in Table 11. (B, impurity In water).

reacted for 2.9 min. Chlorine dioxide residuals were destroyed with excess sodium sulfite. The typical totalion-current chromatograms of the GAC extracts together with that of the XAD-2 extract are shown in Figure 2. It was apparent that compounds recovered from the XAD-2 resin were also recovered from the two carbons, although slightly different recoveries were observed. More importantly, no chlorinated compounds were observed in any of the aqueous extracts. This would indicate that those new compounds formed when GAC was present could only be attributed to the reaction of hydrocarbon with chlorine dioxide on the carbon surfaces. Chlorine Dioxide-Activated Carbon Reaction. The reaction of chlorine dioxide with activated carbon was examined by running a batch experiment using chlorine dioxide (95 mg/L at pH 3.5)/GAC (8 X 16 mesh HD3000) ratios of 0.5 and 2.3 (by weight) for reaction periods up to 3 weeks. Purge-and-trap chromatogramsof the samples did not show significant increases of any volatile compounds when compared to the chromatogram of the chlorine dioxide blank. Additional batch tests were conducted by using a CIOz/GAC ratio of 1.2. An even higher concentration of chlorine dioxide (110,240, or 400 mg/L) was reacted with 60 X 80 mesh HD3000 GAC at pH 3.5. The chlorine dioxide was almost depleted in 10 days; purge-and-trap analyses again gave no evidence of volatile compound formation. The TOX detected in the sample water was less than 5-10 pg/L (as Cl), close to the limit of detection for the procedure. Chlorate ions, measured by the acid o-tolidine method, represented over 22-37% conversion of the initial chlorine dioxide concentration. Chloride ions also increased, but neither CIOz- nor free chlorine was detected. Details of the inorganic chlorine 272

Environ. Scl. Technoi., Vol. 16, No. 5, 1982

Column Depth (cm) Figure 3. TOX buildup on GAC columns after 405-L throughput.

chemistry are still under investigation. Column testa were conducted by applying dilute chlorine dioxide solution to GAC columns. Chlorine dioxide (3.8 mg/L) and its sulfite-quenched solution were applied separately through metering pumps. After 405 L of solution (0.03 g of chlorine dioxide reacted/g of GAC) had passed through the column, purge-and-trap analyses again indicated no volatile organics being produced and released into the effluent from the column. No residual CIOz,free chlorine, ClOf, or chlorate was present in the effluent; the only inorganic product found was chloride. The columns were then dismantled and the GAC was analyzed. The carbon at the inlet contained the greatest number of organics (over 30); however, a majority of them were identical with those in the extract of GAC from the control column. Nevertheless, compounds including p-ethylacetophenone, a-phenylethyl ether, and benzophenone were identified only in the extract of GAC receiving chlorine dioxide. TOX measurements throughout the column profiles (see Figure 3) showed only 0.1 mg of Cl/g of GAC of additional TOX at the inlet of the bed when compared to the TOX (0.22 mg of Cl/g of GAC) at the inlet of the control column. This result reinforced the conclusion that an insignificant quantity of halogenated compounds were formed from the chlorine dioxide-carbon reaction.

Conclusions Hydrocarbons having benzylic hydrogen atoms were readily oxidized by chlorine dioxide. The oxidation products were mainly ketones and alcohols. In the presence of activated carbon, additional halogenated compounds were formed from the chlorine dioxide-hydrocarbon reaction. It has not been determined if the GAC acts as a true catalyst for these transformations

or whether the surface becomes chemically altered. There is a variety of oxygenated surface functional groups on carbon; however, the roles of such surface functional groups and inorganic species in these reactions are not clear. Batch tests using very high dosages of chlorine dioxide with activated carbon (up to 2.3 g of CIOz/g of GAC) at pH 3.5 showed no production of volatile organic compounds and no TOX increase in solution; however, destruction of the chlorine dioxide by the carbon did result in conversion of 22-37 ?% of the chlorine dioxide to chlorate. A column run at a low CIOzdose (3.8 mg/L) produced no volatile compounds in the effluent (after 405-L throughput). TOX analyses showed some TOX on the carbon at the inlet (0.1 mg of Cl/g of GAC) but essentially none through the rest of the column. Soxhlet extraction of the GAC indicated three organic compounds that were not present in the influent, but none of them were halogenated compounds. Acknowledgments

The assistance of A. A. Stevens from the USEPA and J. J. McCreary, now at the University of Florida, is gratefully acknowledged. Literature Cited Snoeyink, V. L.; Clark, R. R.; McCreary, J. J.; McHie, W. F. Environ. Sci. Technol. 1981, 15, 188. Gordon, G.; Kieffer, R. G.; Rosenblatt, D. H. In “Progress in Inorganic Chemistry”; Kippard, S. J., Ed.; Wiley: New York, 1972; Vol. 15, pp 201-286. Rosenblatt, D. H. In “Ozone/Chlorine Dioxide Oxidation products of Organic Materials”; Rice, R. G., Cotruvo, J. A., Eds.; Ozone Press: Cleveland, OH, 1978; pp 332-43. Glabisz, U. Wyd. Uczln. Politech. Szczecin, Poland, 1968; Monograph 44, 127 (Chem. Abstr. 1969, 71, B128450e). Paluch, K. Rocz. Chem. 1964,38, 35-42,43-46. Glabisz, U. Chem. Tech. (Leipzig) 1967, 19, 352. Lindgren, B. 0.; Svahn, C. M.; Widmark, G. Acta Chem. Scand. 1965, 19, 7. Leopold, B.; Mutton, D. B. Tappi 1959,42, 218. Lindgren, B. 0.;Svahn, C. M. Acta Chem. Scand. 1966,20, 211. Masschelein, W. Monographies Dunod, 1969, 74, 168 (Chem. Abstr. 1972, 72, B50474q). Stevens, A. A.; Seeger, D. R.; Slocum, C. J. In ”Ozone/ Chlorine Dioxide Oxidation Products of Organic Materials”; Rice, R. G., Cotruvo, J. A., Eds.; Ozone Press: Cleveland, OH, 1978; pp 3 ~ ~ ~ - 3 9 9 . Miller, G. W.; Rice, R. G.; Robson, C. M.; Kuhn, W.; Wolf, H. In Report of EPA Grant R804385-01, Municipal Environmental Research Laboratory, Office of Water Supply, USEPA, Cincinnati, OH, 1978; pp 9-57 to 9-89. Kennaugh, J. Nature (London) 1957,180, 238. Masschelein, W. J. In “Chlorine Dioxide Chemistry and Environmental Impact of Oxychlorine Compounds”; Ann Arbor Science: Ann Arbor, MI, 1979. Paluch, K.; Otto, J.; Kozlowski, K. Rocz. Chem. 1965,39, 1603. Mallevialle, J. Proc. Int. Conf.Ozone Technol.,2nd 1976, 262-270.

(17) Love, 0. T., Jr.; Carswell, R. J.; Miltner, R. J.; Symons, J. M. In “Interim Treatment Guide for the Control of Chloroform and Other Trihalomethanes”; Symons, J. M., Ed.; Water Supply Research Division, Municipal Environmental Research Laboratory, USEPA Cincinnati, OH, 1976. (18) Vilagenes, R.; Monteil, A.; Derremaux, A.; Lambert, M. “A Comparative Study of Halomethane Formation During Drinking Water Treatment by Chlorine or Its Derivatives in a Slow and Sand Filtration Plant and in Wastewater Treatment Plants”; Paper presented at Proc.-AWWA Annu. Conf., 96th, Anaheim, CA, 1977. (19) Magee, V. Proc. SOC.Water Treat. Exam. 1956, 5, 17. (20) Kim, B. R.; Snoeyink, V. L. In “Activated Carbon Adsorption of Organics from the Aqueous Phase”; Suffet, I., McGuire, M., Eds.; Ann Arbor Science: Ann Arbor, MI, 1980. (21) Snoeyink, V. L.; Lai, H. T.; Johnson, J. H.; Young, J. F. In “Chemistry of Water Supply, Treatment, and Distribution”; Rubin, A. J., Ed.; Ann Arbor Science: Ann Arbor, MI, 1974; pp 233-252. (22) Coughlin, R. W.; Ezra, F. S.; Tan, R. N. J . Colloid Ivterface Sci.-1968, 28, 386. (23) Coughlin, R. W.; Ezra, R. S. Environ. Sci. Technol. 1968, 2, 291. (24) Rided, E. K.; Wright, M. W. J . Chem. SOC.1926,128,1813. (25) Ishizaki, C.; Cookson, J. T., Jr. In “Chemistry of Water Supply, Treatment, and Distribution“; Rubin, A. J., Ed.; Ann Arbor Science: Ann Arbor, MI, 1974; pp 201-231. (26) McCreary, J. J.; Snoeyink, V. L. Environ. Sci. Technol. 1981, 15, 193. (27) McCreary, J. J. Ph.D. Thesis, University of Illinois, Urbana, IL, 1980. (28) Garten, V. A.; Weiss, D. E. Aust. J . Chem. 1957,10, 309. (29) Ingols, R. S.; Ridenour, G. M. J.-Am. Water Works Assoc. 1948, 40, 1207. (30) Granstrom, M. L.; Lee, G. F. Public Works 1957,88, 90. (31) Chen, T. H. Anal. Chem. 1967,39,804. (32) Monscvitz, J. T.; Rexing, D. J. J.-Am. Water Works Assoc. 1981, 73, 94. (33) Mackay, D.; Shiu, W. Y. J . Chem. Eng. Data 1977,22,399. (34) Scarpino, P. V.; Brigano, F. A. 0.;Cronier, S.; Zink, M. L. Project Report, EPA Grant R804418, USEPA, Cincinnati, OH, 1979. (35) Palin, A. T. J . Inst. Water Eng. 1974, 28, 139. (36) Urone, P.; Bonde, E. Anal. Chem. 1960,32, 1666. (37) “Eight Peak Index of Mass Spectra”; Mass Spectrometry Data Centre, AWRE Reading, RG 7, 4 PR, UK, 1974. (38) “Registry of Mass Spectral Data”; Stenhagen, E., Abrahamson, S., McLafferty, F. W., Eds.; Wiley: New York, 1974. (39) “The Mass Spectral Search System”; NIH-EPA Chemical Information System: Information Sciences Corp., Washington, D.C., 1980. (40) Maugh, T. H. Science (Washington,D.C.) 1973,180,578. (41) Robertson, A.; Waters, W. A. J . Chem. Soc. 1948, 1574.

Received for review July 17, 1981. Accepted January 12, 1982. This research was supported by USEPA, Grant No. R805293. The contents of this paper do not necessarily reflect the views and policies of the USEPA, and the mention of trade names and commercial products does not constitute their endorsement.

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