AU666216B2 - Process for removing toxicants from aqueous petroleum waste streams - Google Patents

Description

OPI DATE 03/01/95 AOJP DATE 09/02/95 APPLN. ID 46397/93 I1111 I 111 ii~i I 111 PCT NUMBER PCT/0S93/05820 11111IIhH11111i lwa AU9346397 (SO) International Patent Classification 5 BOlD 15100, C02F 1/28 Al 1I (21) International Application Number: PCTIUS93/05820 (22) International Filing Date: 16 June 1993 (16.06.93) (71) Applicant: CHEVRON RESEARCH AND TECHNOLOGY COMPANY [TJSIUS]; A Division of Chevron U.S.A. Inc., P.O. Box 7141, San Francisco, CA 94120-7141 (US).

(72) Inventors: O'REII.LY, Kirk, 3810 Valley Lane, El Sobrante, CA 94803 SUZUKI. John, 2325 Wright Avenue, Pinoic, CA 94564 (US).

(74) Agents- SHERIDAN, Richard, 3. et at.; Chevron Corporation, Law Department, P.O. Box 7141, San Francisco, CA 94120- 7141 (US).

1) International Publication Number: WO 94/289941 3) International Publication Date: 22 Dccmber 1994 (22.12.94)1 Designated States: AU, CA, JP, KR, NZ, European patent (AT, BE, CH. DE, DK, ES, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE).

Published With inie -national sea rch report, 666216 Af (54) Title: PROCESS FOR REMOVING TOXICANTS FROM AQUEOUS PETROLEUM WASTE STREAMS ELUFON TVEWN[rS (57) Abstract Specific toxicants are. selectively removed from aqueous waste streams associated with the production of petroleum and petroleum products by contacting such aqueous waste stremns with a non-ionic macroreticular polymeric resin having a low to intermediate surface polarity. The toxicants are a group of structurally-related organic molecules containing at least one carboxylic acid group and having a molecular weight in the range of about 200 to about 400. These molecules are toxic to certain indicator species of fish at concentrations of less than 10 parts per billion.

WO 94/28994 PCT/US93105820 2 PROCESS FOR REMOVING TOXICANTS 3 FROM AQUEOUS PETROLEUM WASTE STREAMS 4 BACKGROUND OF THE INVENTION 6 7 FIELD OF THE INVENTION 8 9. The present invention relates to a process for removing an organic toxicant from an aqueous waste stream using a 11 polymeric adsorbent. More particularly, the present 12 invention relates to a process for selectively removing 13 specific organic toxicants from aqueous waste streams 14 associated with the production of petroleum and petroleum .products by contacting such waste streams with a non-ionic 16 macroreticular polymeric resin.

17 18 DESCRIPTICN OF THE RELATED ART 19 Wastewater produced by certain industrial processes often 21 contains toxic materials that are unique to the particular 22 industry involved. Each industry, therefore, seeks to 23 employ the most effective and economical methods available 24 to treat or remove the particular toxicants found in that industries' effluent wastewater.

26 27 In the petroleum industry, a number of methods are currently 28 used to render contaminated wastewater suitable for 29 discharge, including microbial biodegradation and treatment with activated carbon. The treated effluent produced by 31 these processes is typically monitored to determine its 32 suitability for discharge. One increasingly important 33 method of monitoring effluent toxicity uses a bioassay 34 technique in which an indicator species, such as a species of fish known to be sensitive to certain toxicants, is SUBSTITUTE SHEET WO 94/28994 PCTIUS93/05820 -2- 1 exposed to the treated wastewater to determine if the water 2 contains any residual toxicity. In recent years, such 3 bioassays have become more stringent by using indicator 4 species which are increasingly sensitive to the presence of very low levels of aquatic toxicants.

6 7 Using such bioassay techniques, aqueous waste streams 8 associated with the production of petroleum and petroleum 9 products have recently been found to be toxic to certain highly-sensitive species of indicator fish. We have 11 discovered that this toxicity is caused by a specific group 12 of organic materials. These newly-discovered organic 13 materials are present in aqueous waste streams at extremely 14 low levels. However, even at concentrations of less than parts per billion, these materials are highly toxic to the 16 indicator species of fish. Thus, aqueous waste streams 17 containing these materials must be treated prior to 18 discharge to reduce the concentration of these toxicants to 19 an acceptable level.

21 These newly-discovered organic toxicants do not appear to be 22 readily biodegraded under the conditions currently employed 23 to treat aqueous petroleum waste streams. More costly 24 effluent treatment using activated carbon has been found to reduce the concentration of these toxicants to acceptable 26 levels, however, activated carbon is not selective for these 27 specific toxicants and removes most organic matter present 28 in the waste stream. Thus, the use of activated carbon to 29 remove these specific organic toxicants is both inefficient and uneconomical.

31 32 Therefore, a new method or process is required to 33 selectively remove these newly-discovered organic toxicants 34 from aqueous waste streams.

SUBSTITUTE SHEET WO 94/28994 ICT/US93/05820 -3- 1 The use of non-ionic polymeric adsorbents to treat 2 industrial waste effluents has been described previously.

3 For example, R. Kunin in Polymer Engineering and Science, 4 17, 58 (1977), describes the use of non-ionic macroreticular resins, such as AMBERLITE® XAD resins, to treat aqueous 6 industrial wastes containing phenol or various organic 7 acids, bases and neutral organic compounds. R. A. Moore and 8 F. W. Karasek in Intern. J. Environ. Anal. Chem., 17, 187 9 (1984), also discuss the extraction of organic compounds from aqueous media by AMBERLITE® XAD resins.

11 12 Similarly, D. C. Kennedy in Ind. Eng. Chem. Prod. Res.

13 Develop., 12, 56 (1973), describes the adsorption of phenols 14 and chlorinated hydrocarbons from aqueous solutions using AMBERLITE® XAD-4. Also discussed is the use of AMBERLITE® 16 XAD-8 to decolorize kraft pulp mill effluents.

17 18 Bleached kraft effluents have been shown by I. H. Rogers in 19 Bimon. Res. Notes Can. Forest. Serv., 28(4), 24 (1972), to contain organic components which are toxic to sockeye salmon 21 fry (Oncorhynchus nerka). These toxic components were 22 recovered from the kraft mill wastes using AMBERLITE® XAD-2 23 resin. Rogers later reported in J. Am. Oil Chemists' Soc., 24 55, 113A (1978), that the main toxic components of bleached kraft effluents are terpenoid resin acids such as abietic 26 acid, dehydroabietic acid, isopimaric acid, palustric acid 27 and pimaric acid. Such terpenoid resin compounds are not 28 believed to be the cause of the toxicity discussed herein.

29 U.S. Patent No. 3,531,463, issued September 29, 1970 to R.

31 L. Gustafson et al., discloses a process for separating a 32 dissolved water-soluble organic substance having a 33 hydrophobic portion and a hydrophilic portion from an 34 aqueous medium by contacting the medium with particles of an SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 -4- 1 essentially non-ionogenic, macroreticular water-insoluble 2 cross-linked polymer.

3 4 U.S. Patent No. 3,803,030, issued April 9, 1974 to R. A.

Montanaro et al., discloses a process of removing 6 contaminants, such as color bodies and metals, from a liquid 7 medium using a solvent-regenerable macroreticular polymer 8 resin.

9 U.S. Patent No. 3,853,758, issued December 10, 1974 to M. J.

11 Hurwitz et al., also teaches that effluents from dye 12 manufacturing and dyeing operations can be decolorized by 13 using a combination of a primary polymeric adsorbent 14 composed of a non-ionogenic macroreticular adsorbent and a secondary adsorbent comprising a weak-electrolyte ion 16 exchange resin to remove the color bodies.

17 18 U.S. Patent No. 4,297,220, issued October 27, 1981 to E. F.

19 Meitzner et al., discloses a method for adsorbing an organic material from a fluid or fluid mixture using a macro- 21 reticulated crosslinked copolymer.

22 23 Similarly, U.S. Patent No. 4,399,274, issued August 16, 1983 24 to R. T. Goegelman et al., describes a process for isolating and separating non-ionic lipophilic substances, specifically 26 avermectin compounds, from solution in water, organic 27 solvents or miscible mixtures thereof using an insoluble 28 synthetic resin which is an addition copolymer having a 29 cross-linked structure.

31 SUBSTITUTE SHEET PCTIUS93/05820 WO 94/28994 1 SUMMARY OF THE INVENTION 2 3 The present invention is directed to a process for 4 selectively removing a toxicant from an aqueous waste stream associated with the production of petroleum or petroleum 6 products, wherein the toxicant is characterized as a 7 thermally stable organic molecule having a molecular weight 8 in the range from about 200 to about 400 and containing at 9 least one carboxylic acid group, said toxicant being further characterized as toxic to certain indicator species of fish 11 at concentrations of less than about 10 ppb, the process 12 comprising the steps of contacting the waste stream with an 13 activated non-ionic macroreticular polymeric resin having a 14 low to intermediate surface polarity for a time sufficient to reduce the amount of the toxicant in the waste stream to 16 a preselected level and then recovering the water from the 17 resin with a reduced level of toxicity.

18 19 Another embodiment of the invention is directed to a metho1 of detecting the toxicant in an aqueous waste stream, 21 usually an aqueous waste stream associated with the 22 production of petroleum or petroleum products, the method 23 comprising the steps of contacting the aqueous stream with 24 an activated non-ionic macroreticular polymeric resin having a low to intermediate surface polarity for a time sufficient 26 to adsorb a detectable-amount of the toxicant on the resin, 27 then washing the resin with an extraction solvent under 28 conditions effective for removal of organic material from 29 the resin to produce a resin extract in the extraction solvent, and then subjecting a sample of the resin extract 31 to high performance liquid chromatography under conditions 32 effective for detection of the toxicant.

33 SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 -6- 1 BRIEF DESCRTPTION OF THE DRAWINGS 2 3 Figure 1 shows a plot of UV absorbance at 254 nm (in AU) 4 versus elution time (in minutes) for a sample of resin extract subjected to high performance liquid chromatography.

6 7 Figure 2 shows a plot of UV absorbance at 254 nm (in AU) 8 versus elution time (in minutes) for a combined sample of 9- resin extract fractions initially collected at 48, 53, 56, 59, 61, 63 and 76 minutes and re-subjected to high 11 performance liquid chromatography.

12 13 14 DETAILED DESCRIPTION OF THE INVENTION 16 It has now been discovered that certain toxicants that 17 appear to be associated with the production of petroleum or 18 petroleum products can be selectively removed from aqueous 19 waste streams by contacting such aqueous waste streams with a non-ionic macroreticular polymeric resin.

21 22 The toxicants with which the present invention is concerned 23 are the specific organic molecules or group of structurally- 24 related organic molecules having the properties described hereinbelow. These toxicants are hereinafter referred to as 26 the "defined toxicants." 27 28 The terms "aqueous waste stream(s) associated with the 29 production of petroleum or petroleum products" or "aqueous petroleum waste stream(s)" as used herein refer to an 31 aqueous effluent which has contacted petroleum in any of its 32 various crude forms or during its various stages of refining 33 into petroleum products. Such aqueous effluent may, for 34 example, be from crude oil sources, such as producing fields SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 -7- 1 or offshore platforms; refinery process units, such as 2 desalters or separators; or marketing terminals.

3 4 The terms "indicator species of fish" or "indicator fish species" as used herein refer to a species of fish, usually 6 a fresh water species, belonging to the subclass teleostei, 7 commonly referred to as bony fish, that are highly 8 sensitive, especially in the larval form, to certain 9 toxicants and as such serve as indicators of the toxicants presence. Indicator species useful in identifying the 11 presence of the defined toxicants disclosed herein inclih 12 but are not necessarily limited to, the fathead minnow 13 (Pimephales promelas), rainbow trout (Oncorhynchus mykiss), 14 and the threespine stickleback (Gasterosteus aculeatus).

Non-fish species, including invertebrates such as mussels 16 and sea urchins, and plants such as kelp, may also be used 17 as indicator species.

18 19 The Toxicant 21 The defined toxicants with which the present invention is 22 concerned are believed to be a group of structurally-related 23 organic molecules that have been found in aqueous waste 24 streams associated with the production of petroleum or petroleum products. The exact structure of these molecules 26 has not been determined, however, the following description 27 of their primary characteristics will make it possible for 28 one skilled in the art to detect their presence in an 29 aqueous stream.

31 The defined toxicants have a molecular weight in the range 32 of from about 200 to about 400, most probably in the range 33 from about 250 to about 350. The molecules are known to 34 contain at least one or possible more carboxylic acid groups SUBSTITUTE SHEET WO 94/28994 PCTJUS93/05820 -8- 1 and to have both polar and nonpolar functional groups. In 2 addition, the molecules may be a homologous series differing 3 in structure by one carbon atom and may contain an odd 4 number of nitrogen atoms, probably one or three nitrogen atoms.

6 7 The molecules have been found to be thermally stable at 8 temperatures of up to about 100°C for at least 6 hours and 9 chemically stable at temperatures between about 0 and 25 0

C

in solutions of methanol and dichloromethane for periods in 11 excess of one year. The molecules also remain toxic after 12 wet air oxidation (autoclaving) for 20 minutes. The 13 toxicants are soluble in a variety of solvents, including 14 water, methanol, and dichloromethane.

16 The defined toxicants have been identified in the effluent 17 associated with various petroleum processes, including, but 18 not necessarily limited to aqueous effluent from petroleum 19 production sites and refinery waste streams.

21 The presence of the defined toxicants in such aqueous waste 22 streams can be determined by selectively extracting organic 23 material from the stream using an activated non-ionic 24 macroreticular polymeric resin and then analyzing this resin extract using a chromatographic technique, such as high 26 performance liquid chromatography to detect the 27 defined toxicants. High performance liquid chromatography 28 is also useful for preparing a highly purified form of the 29 defined toxicants suitable for determining their level of toxicity to indicator fish species and for structure 31 elucidation studies.

32 33 To determine if thr defined toxicants are present in an 34 aqueous waste stream, the stream is first contacted with an activated non-ionic macroreticular polymeric resin having a SUBSTITUTE

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WO 94/28994 PCT/US93/05820 -9- 1 low to int2rmediate surface polarity, such as the resins 2 described hereinbelow. Prior to use, the resin must be 3 thoroughly pre-treated or activated by washing, rinsing or 4 eluting the resin with a suitable activation solvent. This pretreatment removes any residual organic materials adsorbed 6 on the resin which might interfere with subsequent 7 analytical or structure elucidation studies. Suitable 8 activation solvents are generally volatile organic solvents 9 having an intermediate to high polarity, such as low moleculir weight alcohols, ketones, ethers, esters, and 11 chlorinated hydrocarbons or mixtures thereof. The 12 activation solvent may contain inert liquids, such as water 13 or hydrocarbons, which are not detrimental to the activation 14 process. Preferably, the activation solvent has a dielectric constant greater than about 4 at ambient 16 temperature (20-25 0 Examples of suitable activation 17 solvents include methanol, ethanol, isopropanol, acetone, 18 methyl ethyl ketone, diethyl ether, ethyl acetate, 19 dichloromethane, chloroform and trichloroethane and mixtures thereof. The preferred activation solvent is methanol.

21 22 After washing with the activation solvent, the resin is 23 preferably rinsed with water, prior to contact with the 24 aqueous waste stream, to remove the activation solvent.

26 When contacted with the aqueous stream, the resin 27 selectively adsorbs organic material from the stream, 28 including the defined toxicants if present and other non- 29 toxic organic materials. The resin is typically contacted with a sufficient amount of the aqueous stream for a time 31 sufficient to allow the resin to adsorb a detectable-amount 32 of the defined toxicants. The amount of aqueous waste 33 stream sufficient for the resin to adsorb a detectable- 34 amount of the defined toxicants will vary depending on the concentration of the toxicants in the stream. Typically, SUBSTITUTE

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WO 94/28994 1'CTUS93/05820 1 the resin is contacted with about 0.5 to about 20 liters, 2 preferably about 10 liters, of the aqueous stream being 3 analyzed per gram of rosin. The contact time between the 4 resin and the aqueous stream will also vary depending on the resin composition and its physical properties; the method of 6 contacting the resin and aqueous stream, such as in a batch 7 or continuous mode; and the concentration of defined 8 toxicants in the stream being analyzed. Generally, contact 9 times will range from about 1 to 60 minutes, preferably 2 to 10 minutes.

11 12 After contacting the resin with the aqueous stream for a 13 sufficient period of time, the resin is separated from the 14 stream and extracted with an extraction solvent to remove the organic material adsorbed on the resin. The resin is 16 typically contacted with two volumes of extraction solvent 17 per volume of resin at least once and preferably 3 or more is times. Suitable extraction solvents are the same as the 19 activation solvents described hereinabove, although the extraction solvent need not be the same as the solvent used 21 to activate the resin. The extraction solvent may contain 22 inert liquids, such as water or hydrocarbons, which are not 23 detrimental to the extraction process. Preferred extrarcion 24 solvents are methanol, acetone, dichloromethane, chlorofordiethyl ether and ethyl acetate or mixtures thereof. An 26 especially preferred exttiction solvent is methanol.

27 28 Extraction of the resin gives a resin extract dissolved in 29 the extraction solvent. This resin extract consists of the organic material selectively adsorbed on the resin from the 31 aqueous stream, including the defined toxicants if they were 32 originally present in the aqueous stream. The extract 33 solution can be analyzed directly for the presence of the 34 defined toxicants by high performance liquid chromatography, howover, it is often desirable to remove the extraction SUBSTITUTE

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WO 94/28994 I'CT/US93/05820 -11- 1 solvent by standard separation procedurc such as 2 distillation or evaporation at reduced pressure, to give the 3 resin extract essentially free of extraction solvent. This 4 resin extract can then be redissolved in a suitable solvent, such as methanol, at an appropriate concentration for HPLC 6 analysis. Typically, at least about 1 nanogram, preferably 7 more, of the defined toxicant is required per HPLC injection 8 for suitable detection of the defined toxicants.

9 In a preferred embodiment, a major amount of the non-toxic- 11 organic material is removed from the resin extract prior to 12 HPLC analysis by dissolving the resin extract in a 13 partitioning solvent and intimately contacting this solution 14 with water. This procedure typically removes greater than 90 percent of the non-toxic organic material present in the 16 resin extract. The partitioning solvent is preferably a 17 chlorinated solvent such as dichloromethane, chloroform or 18 trichloroethane. Preferably, the partitioning solvent is 19 dichloromethane.

21 The resin extract in the partitioning solvent is typically 22 contacted with water by shaking the mixture in a separatory 23 funnel and then separating the water layer from the 24 partitioning solvent layer. Other methods of intimately contacting the partitioning solvent solution with water are 26 equally suitable. Preferably, after separating thq 27 partitioning solvent solution from the water layer, the 28 solution is again contacted with water and the layers again 29 separated. Preferably, the partitioning solvent solution is extracted at least 3 times with water. The separated water 31 layers may also be re-extracted with fresh partitioning 32 solvent to recover any of the defined toxicants dissolved in 33 the water layers. The partitioning solvent solutions are 34 then combined and concentrated by distillation or SUBSTITUTE SHEET WO 94/28994 ICT/US93/05820 -12- 1 evaporation under reduced pressure to give a purified resin 2 extract.

3 4 The presence of the defined toxicants in the resin extract is determined by analyzing the extract using high 6 performance liquid chromatography. Under suitable 7 conditions, high performance liquid chromatography separates 8 the defined toxicants from the non-tuxic organic material in the resin extract and thus serves to identify the presence of the defined toxicants in the extract. The HPLC 11 conditions suitable for separating the defined toxicants 12 from the non-toxic material will vary depending on the 13 stationary phase, or column, employed and the robile phase, 14 or eluant, used to elute the column. From the following description, one skilled in the art will be able to 16 determine suitable conditions for detection of the defined 17 toxicants in a sample of resin extract using high 18 performance liquid chromatography.

19 The stationary phase employed is preferably a reverse-phase 21 column. More preferably, the stationary phase is a reverse- 22 phase octadecyl silane column.

23 24 The mobile phase, or eluant, is preferably a polar solvent or mixture of polar solvents, such as water, polar organic 26 solvents, such as acetonitrile and methanol, and dilute 27 aqueous solutions of weakly dissociated acids, such as 28 acetic acid and phosphoric acid.

29 The flow rate of the eluant is typically about 1 mL per 31 minute per 5 mm of column diameter. Eluant fractions may be 32 collected, generally at one minute intervals, using a 33 fraction collector. The detector employed in typically a UV 34 detector, preferably a diode array UV detector. Other SUBSTITUTE

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WO 94/28994 PCT/US93/05820 -13- 1 useful detectors include capillary ion, CI, detectors or CIA 2 detectors.

3 4 When employing an octadecyl silane reverse-phase column, the column in preferably eluted first with a linear triple 6 solvent gradient consisting of water, acetonitrile and a 7 dilute aqueous solution of acetic acid (about 5% and 8 then purged with 100% methanol. The triple solvent gradient 9 is preferably employed as the eluant from the initial time of injection of the resin extract to about 65 minutes after 11 injection. The column is then purged with methanol from 12 about 65 minutes after injection to about 85 minutes after 13 injection. The column in then re-equilibrated with the 14 triple solvent gradient from about 85 minutes after injection to about 120 minutes after injection.

16 17 The exact elution times for the defined toxicants will vary 18 depending on the high performance liquid chromatography 19 conditions. Using the specific conditions described hereinabove, the defined toxicants consistently elute in two 21 regions between about 48 to about 65 minutes and about 75 to 22 about 80 minutes. The 48 to 65 minute region represents 23 about 75-85% of the toxicity and the region from 75 to 24 minutes represents the remaining 15-25% toxicity. The two regions of toxicity may represent two distinct sub-classes 26 of compounds. The eluant containing the defined toxicants 27 can also be subjected to other analytical techniques, such 28 as GC MS/MS, to further confirm the presence of the defined 29 toxicants or for structure elucidation studies.

31 The defined toxicants are highly toxic to certain indicator 32 species of fish. The toxicity can be measured by well-known 33 procedures, such as those described by the Environment 34 Protection Agency in "Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms" SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 -14- 1 (EPA/600/4-85/013, March 1985). Short-term chronic toxicity 2 can be determined using "Short-Term Methods for Estimating 3 the Chronic Toxicity of Effluents and Receiving Waters to 4 Marine and Estuarine Organisms" (EPA/600/4-87/028, May 1988). The toxicity is typically measured as the 96-hour 6 median lethal concentration ("96-hour LC 50 This is the 7 concentration of toxicant in water that is lethal to 50% of 8 the indicator species during a 96-hour te t period. For the 9 defined toxicants described in the present invention, the 96-hour LC 50 is typically expressed in AL of extract per 11 liter of bioassay, AL/L, because of the difficulty in 12 isolating sufficient quantities of the defined toxicants to 13 determine an LC 5 by weight.

14 The most sensitive indicator species to the defined 16 toxicants described in this invention is the 30 to 17 old rainbow trout (Oncorhynchus mykiss). Using crude resin 18 extract, the 96-hour LC 50 value for rainbow trout is about 19 31 tL/L. Another sensitive indicator species is the larval stage of fathead minnow (Pimephales promelas), which has a 21 96-hour LC 50 for the crude extract of about 52 L/L. An 22 estuarine indicator species, the threespine stickleback 23 (Gasterosteus aculeatus) has a 96-hour LC 50 value for the 24 crude extract of about 87 AL/L.

26 These newly-discovered toxicants are substantially more 27 toxic than any organic materials previously known to be 28 present in aqueous petroleum waste streams. For example, 29 naphthenic and natural petroleum sulfonic acids, commonly associated with petrole'lm wastewaters, have a 96-hour LC 50 31 value in the fathead minnow bioassay of at least about 32 ppm, whereas the newly-discovered toxicants are toxic at 33 concentrations of less than .01 ppm or 10 ppb.

34 SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 1 The Polymeric Absorbent 2 3 The non-ionic macroreticular polymeric resins employed in 4 the process of the present invention are well-known in the art. Suitable resins, for example, are described in 6 Industrial and Engineering Chemistry, Product Asearch and 7 Development, 12, 56 (1973). A number of such resins are 8 commercially available, including those sold under the 9 tradenames AMBERLITE® XAD by Rohm and Haas Company, Philadelphia, Pennsylvania; DUOLITE ES by Chemical Process' 11 Company, Redwood City, California; and DIAION® HP by 12 Mitsubishi Chemical Industries Limited, Tokyo, Japan.

13 14 These non-ionic macroreticular polymeric resins are generally prepared by polymerizing cross-linking monomers or 16 mixtures of monomers in the presence of a phase separating 17 solvent which is miscible with the monomers, but which does 18 not dissolve the polymer. Typical procedures for preparing 19 suitable macroreticular resins are described in U.S. Patent Nos. 3,275,548, 3,357,158, 3,663,467, 4,224,415 and 21 4,297,220, the entire disclosures of which are incorporated 22 herein by reference.

23 24 Typical non-ionic macroreticular polymeric resins which may be employed include, for example, the granular cross-linked 26 polymers prepared by suspension polymerization of 27 polymerizable ethylenically unsaturated molecules comprising 28 about 10 to 100 weight percent, preferably 40 to 100 weight 29 percent, of at least one poly(vinylbenzene) monomer selected from the group consisting of divinylbenzene, 31 trivinylbenzene, alkyl-divinylbenzenes having from 1 to 4 32 alkyl groups of 1 to 2 carbon atoms substituted in the 33 benzene nucleus, and alkyltrivinylbenzenes having 1 to 3 34 alkyl groups of 1 to 2 carbon atoms substituted in the SUBSTITUTE

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WO 94/28994 I'CT/US93/05820 -16- 1 benzene nucleus, such as those described in U.S. Patent No.

2 3,531,463. In addition to the homopolymers and copolymers 3 of these poly(vinylbenzene) monomers, suitable resins may be 4 prepared by copolymerizing one or more of these poly(vinylbenzene) monomers with up to 90 percent (by weight 6 of the total monomer mixture) of monoethylenically 7 unsaturated monomers, or polyethylenically unsaturated 8 monomers other than the poly(vinylbenzenes) defined 9 hereinabove or a mixture of and 11 Examples of the alkyl-substituted di- and trivinylbenzenes 12 are the various divinyltoluenes, the divinylxylenes, 13 divinylethylbenzene, 1,4-divinyl-2,3,5,6 tetramethylbenzene, 14 1,3,5-trivinyl-2,4,6-trimethylbenzene, 1,4-divinyl, 2,3,6triethylbenzene, 1,2,4-trivinyl-3,5-diethylbenzene, 1,3,5- 16 trivinyl-2-methylbenzene.

17 18 Examples of other non-ionic polyethylenically unsaturated 19 compounds, which can comprise up to 90 weight percent of the polymer, include: divinylnaphthalenes, diallyl phthalate, 21 ethylene glycol diacrylate, ethylene glycol dimethacrylate, 22 divinylsulfone, polyvinyl or polyallyl ethers of glycol, of 23 glycerol, of pentaerythritol, of monothio or dithio- 24 derivatives of glycols, and of resorcinol, divinylketone, divinylsulfide, allyl acrylate, diallyl maleate, diallyl 26 fumarate, diallyl succinate, diallyl carbonate, diallyl 27 malonate, diallyl oxalate, diallyl adipate, diallyl 28 sebacate, divinyl sebacate, diallyl tartrate, dially 29 silicate, triallyl tricarballylate, triallyl aconitate, triallyl citrate, triallyl phosphate, N,N'- 313 methylenediacrylamide, N,N'-methylenedimethacrylamide, N,N'- 32 ethylenediacrylamide, trivinylnaphthalenes, and 33 polyvinylanthracenes.

34 SUBSTITUTE SHEET WO 94/28994 PCT/US93/ 82 -17- 1 Examples of non-ionic monoethylenically unsaturated monomers 2 that may be used in making the macroreticular resins include 3 methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl 4 acrylate, butyl acrylate, ethylhexyl acrylate, cyclohexyl acrylate, isobornyl acrylate, benzyl acrylate, phenyl 6 acrylate, alkylphenyl acrylate, ethoxymethyl acrylate, 7 ethoxyethyl acrylate, ethoxypropyl acrylate, propoxymethyl 8 acrylate, propoxyethyl acrylate, propoxypropyl acrylate, 9 ethoxyphenyl acrylate, ethoxybenzyl acrylate, ethoxycyclohexyl acrylate, and the corresponding esters of- 11 methacrylic acid, ethylene, propylene, isobutylene, 13 diisobutylene, styrene, vinyltoluene, vinyl chloride, vinyl 13 acetate, vinylidene chloride, acrylonitrile, etc.

14 Polyethylenically unsaturated monomers which ordinarily act as though they have only one such unsaturated group, such as 16 isoprene, butadiene, and chloroprene, may be used as part of 17 this monoethylenically unsaturated category. These monomers 18 can be used in a concentration of up to 90 weight percent of 19 the polymer.

21 Alternatively, the non-ionic all aliphatic macroreticular 22 polymeric resins as exemplified in U.S. Pat. No. 3,663,467 23 may be used as the adsorbent in the process of the present 24 invention. These resins are essentially all aliphatic in character and are crosslinked with a polyfunctional 26 methacrylate (containing at least three methacrylate 27 groups). The preferred polyfunctional methacrylate is 28 trimethylolpropane trimethacrylate or pentaerythritol 29 tetramethacrylate. However, the trimethacrylate of glycerol, glucose pentamethacrylate, sorbitol 31 hexamethacrylate and the polyfunctional methacrylates of 32 polyhydric alcohols of 3 to 6 carbon atoms in chain length 33 may also be used. These poly-functional methacrylates must 34 contain at least three methacrylate groups as heretofore noted. Sutro polyols which are commercially available SUBSTITUTE

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WO 94/28994 ICT/US93/05820 -18- 1 mixtures of essentially straight chain polyhydric alcohol of 2 3 to 6 -arbon atoms may be used as the source of polyhydric 3 alcohol.

4 These all-aliphatic polymers contain 10 to 100 percent by 6 weight of the polyfunctional methacrylate having at least 3 7 methacrylate groups, and preferably from 40 to 100 percent 8 by weight of said polyfunctional methacrylate. Typical 9 aliphatic, non-aromatic, non-ionic, monoethylenically unsaturated co-monomers which may be copolymerized with the 11 polyfunctional methacrylate include, for example, ethylene, 12 isobutylene, acrylonitrile, methacrylonitrile, acrylamide, 13 methacrylamide; diacetone acrylamide, vinyl esters 14 (including vinyl chloride, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl laurate), vinyl ketones (including 16 vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropyl 17 ketone, vinyl n-butyl ketone, vinyl hexyl ketone, vinyl 18 octyl ketone, methyl isopropenyl ketone), vinyl ethers 19 (including vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, vinyl isobutyl ether), vinylidene compounds 21 (including vinylidene chloride, bromide, or bromochloride), 22 esters of acrylic acid and methacrylic acid such as the 23 methyl, ethyl, 2-chloroethyl, propyl, isopropyl, n-butyl, 24 isobutyl, t-butyl, sec-butyl, amyl, hexyl, glycidyl, ethoxyethyl, cyclohexyl, octyl, 2-ethylhexyl, decyl, 26 dodecyl, hexadecyl and octadecyl esters of these acids, 27 hydroxyalkyl methacrylates and acrylates such as 28 hydroxyethyl methacrylate and hydroxypropyl methacrylate, 29 substituted acrylamides, such as N-monoalkyl, -N,N-dialkyl, and N-dialkyl-aminoalkylacrylamides or methacrylamides where 31 the alkyl groups may have from 1 to 18 carbon atoms, such as 32 methyl, ethyl, isopropyl, butyl, hexyl, cyclohexyl, octyl, 33 dodecyl, hexadecyl, and octadecyl. If desired, difunctional 34 methacrylates such as ethylene glycol dimethylacrylate or SUBSTITUTE

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WO 94/28994 PCT/US93/05820 -19- 1 trimethylolpropane dimethacrylate can be used as co- 2 monomers.

3 4 The ability of a particular resin to selectively adsorb the defined toxicants described herein in preference to other 6 non-toxic organic material is determined in large part by 7 the surface properties of the resin. Such surface 8 properties include surface polarity, surface area and 9 average pore diameter.

11 Suitable resins have a surface area in the range of about 12 100 to about 1,000 m2/g, and an average pore diameter in the 13 range of about 20 to about 250 A. Preferably, the resin 14 will have a surface area of about 400 to about 800 m2/g, more preferably about 450 m2/g, and an average pore diameter 16 of about 50 to about 90 A, more preferably about 80 A.

17 18 Useful resins also have a low to intermediate surface 19 polarity. Surface polarity is generally related to the inherent dipole moment of the functional group or groups 21 present in the monomer or mixture of monomers used to 22 prepare the polymeric resin. Monomers containing functional 23 groups which have a low inherent dipole moment, such as 24 styrene and divinylbenzene, typically have a low surface polarity. Monomers containing functional groups having an 26 intermediate inherent dipole moment, sach a acrylate erters, 27 have an intermediate surface polarity. Preferably, the 28 resins used in the present process have an intermediate 29 surface polarity.

31 More polar ion-exchange resins, such as Dowex Anion 1X8, 32 have been found to readily adsorb a majority of the organic 33 material in aqueous petroleum waste streams, including the 34 newly-discovered toxicants described herein. These resins, however, are not easily regenerated, since the adsorbed SUBSTITUTE

SHEET

WO 94128994 PCT/US93/05820 1 organic matter cannot be sufficiently eluted from such 2 resins using a suitable solvent. More importantly, the use 3 of such resins for the treatment of aqueous petroleum waste 4 streams is generally undesirable, btduse such waste streams typically contain relatively high concentrations of sulfate 6 anions or other fouling agents which rapidly saturate anion 7 exchange resins.

8 9 The non-ionic macroreticular polymeric resins are typically employed in this invention in the form of beads or granules 11 having a particle size of about 0.1 to about 3 millimeters 12 average diameter. Nominal mesh sizes range from about 20 to 13 about 14 In a preferred embodiment of the present invention, the non- 16 ionic macroreticular polymiiric resin is a copolymer of 17 styrene and divinylbenzene having a low surface polarity and 18 a surface area in the range of about 300 to about 800 m2/g, 19 preferably about 750 m /g and an average pore diameter of about 50 to about 90 A, preferable about 50 A. Resins 21 having these properties are commercially available from Rohm 22 and Haas Company under the tradenames AMBERLITE® XAD-2 and 23 AMBERLITE® XAD-4.

24 In a more preferred embodiment, the non-ionic macroreticular 26 polymeric resin is a polymer of a polyfunctional 27 methacrylate, preferable trimethylolpropane trimethacrylate, 28 having an intermediate surface polarity and a surface area 29 in the range of about 100 to 400 m2/g, preferably about 450 m2/g and an average pore diameter of about 80 to about 250 31 A, preferably about 80 A. Resins having these properties 32 are commercially available under the tradenames AMBERLITE® 33 XAD-7 and AMBERLITE® XAD-8 from Rohm and Haas Company.

34 AMBERLITE® XAD-7 resin represents an especially preferred resin for use in the process of this invention.

SUBSTITUTE

SHEET

WO 94/28994 PCT/US93/05820 -21- 1 2 Process Conditions 3 4 In the adsorption process of the present invention, the defined toxicanvs are removed from an aqueous waste stream 6 by contacting the waste stream with an activated non-ionic 7 macroreticular polymeric resin having a low to intermediate 8 surface polarity, such as the resins described hereinabove.

9 The resin is contacted with the waste stream for a time sufficient to reduce the amount of the defined toxicants in 11 the waste stream to a preselected level. The waste stream 12 is then recovered from the resin with a reduced level of 13 toxicity.

14 The adsorption process may be conducted in batch, semi- 16 continuous or continuous operation. In a batch operation, 17 for example, loose non-ionic macroreticular polymeric resin 18 is mixed in a vessel of appropriate size with aqueous 19 petroleum wastewater and, after sufficient contact time, the treated aqueous effluent is separated from the resin by 21 filtration, centrifugation, decantation and the like. Two 22 or more batch reactors may be used in series for increased 23 adsorption efficiency.

24 Preferably, the process is conducted in a continuous 26 operation. In continuous operation, the resin may be 27 supported in a suitable vessel which, in most practical 28 operations, normally take the form of a towe- or column 29 suitably packed with the resin particles.. The aqueous petroleum waste stream is passed through the resin mass at a 31 suitable rate, such as top to bottom, or vice versa such 32 that the defined toxicants are adsorbed on the resin.

33 Alternatively, the resin particles may pass in counter- 34 current relation to the aqueous effluent. For example, the resin granules may be continuously fed to the top of a SUBSTITUTE

SHEET

WO 9428994 PCT/US93/05S20 -22- 1 column or tower into the bottom of which the effluent is fed 2 continuously, the granules being removed from the bottom for 3 subsequent regeneration. In an alternative embodiment, the 4 resin may be immobilized on a suh-trate, for example on a grid or on the walls of a vessel, and the effluent passed 6 over or through the resin.

7 8 The resin is contacted with the waste stream being treated 9 for a time sufficient to reduce the amount of the defined toxicants to a preselected level. The concentration of the 11 defined toxicants will normally be reduced to a level which 12 is no longer toxic to the indicator species of fish.

13 Preferably, the defined toxicants will be reduced to a level 14 such that the defined toxicants are no longer detectable using the methods of the present invention. The defined 16 toxicants are preferably reduced to a concentration of less 17 than about 2 ppb, more preferably less than 0.1 ppb.

18 19 Contact time between the resin and the aqeous effluent will vary depending on the resin composition and ph-yical 21 properties; the method of operation, such a. batch or 22 continuous; and the concentration of toxicant in the 23 effluent being treated. Generally, contact times will range 24 from about 1 to 60 minutes, preferably 2 to 10 minutes.

26 Prior to use, the resins employad in the process of this 27 invention are pre-treaced or activated by washing, rinsing 28 or eluting the resin with a suitable activation solvent.

29 This pretreatment removes any residual organic materials adsorbed on the resin thus increasing the resin's capacity 31 to adsorb the toxicant materials. Suitable activation 32 solvents are generally volatile organic solvents having an 33 intermediate to high polarity, such as low molecular weight 34 alcohols, ketones, ethers, esters, and chlorinated hydrocarbons or mixtures thereof. The activation solvent SUBSTITUTE

SHEET

WO 94/28994 PCT/US93/058 2 0 -23- 1 may contain inert liquids, such as water or hydrocarbons, 2 which are not detrimental to the activation process.

3 Preferably, the activation solvent has a dielectric constant 4 greater than about 4 at ambient temperature (20-25 0

C).

Examples of suitable activation solvents include methanol, 6 ethanol, isopropanol, acetone, methyl ethyl ketone, diethyl 7 ether, ethyl acetate, dichloromethane, :hloroform, 8 trichloroethane or mixtures thereof. The preferred 9 activation solvent is methanol.

11 The resin can be employed in the absor ion process until 12 the adsorption capacity of resin has been reached. The 13 resin may then be regenerated or reactivated by washing the 14 resin with one or more of the activation solvents described hereinabove to remove the adsorbed organic material.

16 Preferably, the resin is regenerated by washing with 17 methanol. The resin is typically washed for a time 18 sufficient to remove essentially all of the adsorbed organic 19 material, thus reactivating the resin for reuse. During the regeneration process, the resin is typically contacted with 21 the activation solvent for at least about 5 minutes, more 22 preferably about 10 to about 30 minutes. The resin is 23 typically washed with 3 bed volumes, preferably 5 to 7 Led 24 volA-as, of the activation solvent. After washing, the reactivated resin is recovered or separated from the 26 activation solvent for reuse. The activation solvent used 27 for the regeneration process can also be recovered using 28 standard solvent purification procedures, such as 29 distillation, and the purified solvent recycled.

31 While other means have been found to remove the toxicant 32 from aqueous waste streams, the process of the present 33 invention has certain advantages over other methods. The 34 non-ionic macroreticular polymeric -esins have been found to have a high selectivity for removing the defined toxicants SUBSTITUTE SHEET WO 94/28994 iCT/US93/05820 -24- 1 as compared to activated carbon. Thus, less adsorbent is 2 required to remove the same amount of toxicant from a waste 3 stream as compared to activated carbon. This translates 4 into less bulk, an increase in the time between regenerations, and a reduction in the size of the equipment 6 needed to accomplish the same degree of treatment. Another 7 advantage is that reactivation of the resin may be carried 8 out on site as contrasted with the use of activated carbon 9 which generally requires off site reactivation. Ion exchange resins while capable of removing the toxicant are- 11 either not regenerable or may be regenerated only with great 12 difficulty. Thus, the present invention makes it possible 13 to develop a continuous process having the steps of 14 regenerating the adsorbent on site by contacting it with a suitable activating solvent, recovering the activating 16 solvent with the dissolved toxicant from the adsorbent, 17 returning the adsorbent to service, and recycling the 18 solvent. Further, using the present invention, a continuous 19 processing flow scheme is possible in which treatment vessels containing the resin are connected in parallel, such 21 that the vessels may be taken out of service for resin 22 regeneration while other vessels continue to treat the 23 effluent.

24 26 EMAMPLES 27 28 The following examples are presented to illustrate specific 29 embodiments of the practice of this invention and should not be interpreted as limitations upon the scope of the 31 invention.

32 33 SUBSTITUTE

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WO 94/28994 I'CT/US93/05820 1 Example 1 2 Activation of AMBERLITE® XAD-7 Resin 3 4 AMBERLITE® XAD-7 resin (1 kilogram) was extracted in a soxhlet apparatus with HPLC-grade methanol for eight hours 6 to remove residual organic contamination. The methanol- 7 washed resin was then stored, for up to one year, in HPLC- 8 grade methanol in a glass container. Prior to use, the 9 methanol-washed resin was placed in a 2-liter glass column and washed with 5 column volumes of HPLC-grade water to 11 produce an activated resin suitable for toxicant adsorption.

12 13 Examples 2A-G 14 Toxicant Adsorption Using AMBERLITE® XAD-7 Resin 16 Activated AMBERLITE® XAD-7 resin from Example 1, in amounts 17 ranging from 5.0 g/L to 0.025 g/L, was stirred at room 18 temperature for 2 hours with 4.0 L of water collected from 19 the outlet of a refinery effluent treatment system. Each mixture was filtered and the total organic carbon ("TOC") 21 concentration determined using an 0I Corporation Model 700 22 TOC analyzer. The analyzer had a reproducibility of about 23 1-2 ppm. The initial untreated effluent had a TOC of 27.7.

24 The TOC after treatment with each amount of resin is shown in Table 1.

26 27 The toxicity of each treated effluent was then determined 28 using 30-90 day old rainbow trout by following procedures 29 essentially as described in Example 10. The percent of fish surviving after 96-hours was recorded. In the untreated 31 effluent, 20 percent of the fish survived. The percent 32 survival after treatment of the effluent with various 33 amounts of resin is shown in Table 1.

34 SUBSTITUTE

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WO 94/28994 PCT/US93/05820 -26- 1 Example 3A-F 2 Toxicant Adsorption Using AMBERLITE® XAD-2 Resin 3 4 AMBERLITE® XAD-2 was stirred with water collected from the outlet of a refinery effluent treatment system using the 6 procedures described in Example 2. Prior to use, the resin 7 had been activated using the procedures of Fxample 1. The 8 TOC and the percent of fish surviving in the effluent after 9 treatment with each amount of resin is shown in Table 1.

11 Example 4A-F 12 Toxicant Adsorption Using AMBERLITE® XAD-4 Resin 13 14 AMBERLITE® XAD-4 was stirred with water collected from the outlet of a refinery effluent treatment system using the 16 procedures described in Example 2. Prior to use, the resin 17 had been activated using the procedures of Example 1. The 18 TOC and the percent cf fish surviving in the effluent after 19 treatment with each amount of resin is shown in Table 1.

21 Example 5A-F (Comparative) 22 Toxicant Adsorption Using Activated Carbon 23 24 Activated carbon (Calgon Filtersorb 300) was stirred with "ater collected from the outlet of a refinery effluent 26 treatment system using the procedures described in Example 27 2. Prior to use, the carbon was washed with distilled water 28 to remove fines. The TOC and the percent of fish surviving 29 in the effluent after treatment with each amount of carbon is shown in Table 1.

31 32 The data in Table 1 shows that activated carbon (Examples 33 5A-F) removed significantly more total organic carbon (TOC) 34 from the effluent than either AMBERLITE® XAD-2, XAD-4 or XAD-7 (Examples 2A-G, 3A-F and 4A-F, respectively). For SUBSTITUTE

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WO 94/28994 PCT/US93/05820 -27- 1 example, at 5 grams of adsorbent per liter of effluent, 2 activated carbon removed 72% of the TOC (Example 3 whereas AMBERLITE® XAD-7 removed 30% of the TOC (Example 4 2A). Although AMBERLITE® XAD-7 removed less TOC than activated carbon, 100% fish survival was observed for both 6 adsorbents. Therefore, the AMBERLITE® resin is more 7 selective than activated carbon for adsorption of the 8 defined toxicants.

9 SUBSTITUTE

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WO 94/28994 PCT/US93 /05820 -28- TABLE 1 Ex. Adsorbent T0C I After %TOC 2 No. Adsorbent Conc. Adsorption Adsorption Survival 3 2A XAD-7 5.00 19.4 30% 100 2B XAD-7 3.00 20.3 27% NA 2C XAD-7 1.00 22.1 20% 100 2D XAD-7 0.50 23.9 14% 100 2E XA1D-7 0.10 26.0 6% 100 2F XAD-7 0.05 26.8 3% 100 2G XAD-7 0.025 27.7 100 3A XAD-2 5.00 14.8 47% NA 3B XAD-2 3.00 16.4 4 1% NA 3C XAD-2 1.00 19.0 31% NA 3D XAD'"2 0.50 22.2 20% NA 2E XAD-2 0.10 23.6 15% NA 3F XAD-2 0.05 26.0 6% NA 4A XAD-4 5.00 20.0 28-% 100 4B XAD-4 3.00 22.3 19% NA 4C XAD-4 1.00 25.2 9% 0 4D XAD-4 0.50 25.5 8% 0 4E XAD-4 0.10 27.3 1% 0 4F XAD-4 0.05 27.6 0 A. Carbon 5.00 7.9 72% 100 A. Carbo~n 3.00 12.8 54% NA A. Carbon 1.00 20.5 26% 100 A. Carbon 0.50 21.5 22% 100 SE A. Carbon 0.10 25.5 8% 100 SF A. Carbon 0.05 26.6 4% 100 2 TOC Total Organic Carbon (Initial TOC =27.7) 3 Percent total organic carbon adsorbed by adsorbent.

Percent of fish surviving after 96-hours; 20% survival in untreated effluent; NA not available.

SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 -29- 1 2 Example 6 3 Toxicant Adsorption Usinc AMBERLITE® XAD-7 Resin 4 Activated AMBERLITE® XAD-7 resin (1200 grams) from Example 1 6 was placed in a 2100 mL glass column and water collected 7 from the outlet of a refinery effluent treatment system was 8 passed through the column at the rate of one column volume 9 every two minutes. A total of 2460 L (650 gallons) of effluent water was passed through the column to give an 11 effluent-contacted resin.

12 13 Example 7 14 Toxicant Isolation from AMBERLITE® XAD-7 Resin 16 The effluent-contacted AMBERLITE® XAD-7 resin from Example 6 17 was extracted three times with two column volumes of HPLC- 18 grade methanol to remove the organic material, including the 19 defined toxicants. The combined methanol extracts were transferred in small portions to a round-bottomed flask and 21 roto-evaporated to dryness on a Buchi rotovapor with an 22 attached water bath maintained at 300C. The dried organic 23 material was then reconstituted with HPLC-methanol and 24 brought up to a fixed volume of 100 mL. This stock solution was used for further isolation and characterization 26 experiments.

27 28 Example 8 29 Toxicant Purification Usinq Solvent:Solvent Partitioning 31 A 10 mL aliquot of the stock solution from Example 7 was 32 roto-evaporated to dryness on a Buchi rotovapor with an 33 attached water bath maintained at 30 0 C. The dried sample 34 was reconstituted with four separate 25 mL portions of HPLCgrade water and the water solutions were combined in a 250 SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 1 mL separatory funnel. The round-bottomed flask which 2 contained the sample was then washed with four separate 3 mL portions of HPLC-grade dichloromethane and the 4 dichloromethane washings were transferred to the same 250 mL separatory funnel containing the reconstituted sample. The 6 separatory funnel was mixed by inversion for about 5 minutes 7 and then allowed to settle undisturbed for 60 minutes to 8 allow the water and dichloromethane layers to separate. The 9 dichloromethane layer was then drained into another 250 mL separatory funnel, and 100 mL of fresh HPLC-grade water was 11 added to this funnel. An additional 100 mL of fresh 12 dichloromethane was also added to the first separatory 13 funnel. Both funnels were mixed by inversion for about 14 minutes and allowed to settle until the water and dichloromethane layers had separated. This procedure was 16 repeated with the addition of a third separatory funnel.

17 The initial water sample was extracted three times with 18 fresh HPLC-grade dichloromethane, and each dichloromethane 19 portion was extracted three times with fresh HPLC-grade water. All dichloromethane portions were then combined.

21 22 Example 9 23 HPLC Fractionation of the Toxicant 24 The dichloromethane extract from Example 8 was roto- 26 evaporated to dryness and brought to a volume of 10 mL in a 27 volumetric flask using HPLC-grade methanol. This sample was 28 then filtered through a 0.2 micron syringe filter, and 200 29 AL injected into a Waters HPLC system.

31 The HPLC system consisted of a Waters Model 600 pump 32 equipped with 100 uL pump heads interfaced to a Waters Model 33 600E gradient controller. Injections were made with a 34 Waters 712 WISP Auto-sampler equipped with refrigeration, set at 5 0 C. The detectors were a Waters Model 991 SUBSTITUTE

SHEET

PCT/US93/05820 WO 94/28994 -31- Photodiode Array ultraviolet detector, set to scan 190 to 400 nm, and a Waters Model 410 Differential Refractometer, set at full scan. The column used was a Beckman Ultrasphere ODS (10 X 250 mm) protected with a Rainin ODS guard column (4.6 X 30 mm). The HPLC components were interfaced to a NEC 386/25 CPU which controlled all operation parameters, data collection, and data integration during the HPLC run using the following software packages: Waters 991 Powerline Control ver. 6.22a Water 991 Foreground/Background ver. 6.22a Wat i- 4 Channel A/D Control Card APC-IV ver.

Microsoft MS DOS 3.3 rev. Microsoft Windows 3.0 run time version The eluant was Time (Min.) 0-50 50-55 55-60 60-65 65-85 85-120 as follows: 3A 5.0 90.0 90.0 5.0 90.0 10.0 5.0 90.0 0.0 0.0 5.0 90.0

C

5. 0 5.0 0.0 5.0 0.0 5.0

D

0.0 0.0 0.0 0.0 100.0 0.0 5% v/v solution The flow rate where A is water, B is acetonitrile, C is a of acetic acid in water, and D is methanol.

was 2 mL per minute.

An LKB Super Rac fraction collector, activated by HPLC control, was used to collect 120 fractions at 1 minute intervals starting from time 0 (the time of sample injection). The HPLC chromatogram for this run showing UV absorbance versus elution time is shown in Figure 1.

SUBSTITUTE

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WO 94/28994 PCT/US93/05820 -32- 1 Each of the 120 fractions was analyzed for toxicity using 2 the fathead minnow larvae 96-hour bioassay screening 3 described in Example 10. Fractions found to be toxic were 4 further screened for LCso determination using fathead minnow larvae. The results of these bioassays are shown in Table 2 6 (Example 9A). Table 2 also shows the results of an 7 identical HPLC run using a 400 gL sample of the same 8 methanol solution (Example 9B) and a repeat run using a 200 9 tL sample (Example 9C).

11 The data in Table 2 shows that the defined toxicants were 12 present in the eluant fractions collected in the range from 13 about 48 to about 65 minutes and about 75 to about 14 minutes.

16 Re-injection of a combined sample of the fractions collected 17 at 48, 53, 56, 61, 63 and 76 minutes under the same HPLC 18 conditions gave a series of sharp peaks shifted downward by 19 about one minute from each original peak as shown in Figure 2.

21 SUBSTITUTE

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.WO 94/28994 CUS3150 PCTIUS93/05820 -33- TA~BLE 2

HPLC

Sample No.

1-47 48 49 51 592 53 54 56 57 58 59 61 62 63 64 66-74 76 77 78 79 8 1-120 Example 9A (200 /AL) 96-li Rel~ LCr~n Tox.

NT' 0.0 136 1.8 136 1.8 208 1.2 136 1.8 155 1.6 178 1.4 229 1.1 146 1.7 136 1.8 146 1.7 155 1.6 89 2.8 146 1.7 164 1.5 164 1.5 155 1.6 NT 0.0 250 1.0 NT 0.0 NT 0.0 155 1.6 155 1.6 155 1.6 NT 0.0 NT 0.0 NT 0.0 Total: 32.4 Example 9B Example 9C (400 jgL) (200 /iL) 96-h Rel. 96-h Rel.

LC;n Tox. Tox.

NT

165 177 164 190 146 76 146 136 82 65 86 78 62 60 78 74 100 177

NT

NT

62 62 95 92 114

NT

Total: 0.0 1.5 1.4 1.5 1.3 1.7 3.3 1.7 1.8 3.0 3.8 2.9 3.2 4.0 4.2 3.2 3 41 2.5 1.4 0.0 0.0 4.0 4.0 2.6 2.7 2.2 0.0 61.3 177 190 177 155 155 99 107 146 88 71 73 82 88 95 106 106 250

NT

NT

88 88 146 155 165 213

NT

Total: 0.0 1.4 1.4 1.6 1.6 2.3 1.7 2.8 3.2 3.4 3.1 2.8 2.6 2.4 2.4 0.0 0.0 2.8 2.8 1.7 1.6 1.2 0.0 49.1.

In AL/L.

Relative NT Not toxicity: an LC 50 toxic.

of 250 AL/L SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 -34- 1 2 Example 3 Toxicant Bioassay 4 The acute toxicity of test samples was determined using a 6 fathead minnow larvae (Pimephales promelas) bioassay. In 7 this test, 3-8 day old fathead minnow larvae, available from 8 Aquatic Resources, Inc., Sebastopol, California, are 9 maintained for at least two days under the same environmental conditions and feeding regime that will exist 11 during the bioassay. During this acclimation period, 12 mortality is recorded daily and the larvae.are not used if 13 the mortality is greater than 10% or if the larvae exhibit 14 abnormal behavior or appearance.

16 The test solution is prepared by combining the appropriate 17 volumes of test material or stock solution and diluent 18 water. The diluent water has a dissolved oxygen 19 concentration between 60 and 100%, a pH in the range of 7.3- 7.7, and a temperature in the range of 16 0 C to 24 0

C.

21 22 To begin the test, a 30-mL glass beaker is filled with 20 mL 23 of the test solution and five fathead minnow larvae are 24 transferred to the test solution using a medicine dropper (eyedropper). Only larvae having a normal appearance and 26 size are selected for the bioassay. When the larvae have 27 been transferred, the glass beaker is lightly covered with 28 thin plastic film to limit evaporation and loss of volatile 29 materials, while allowing some air circulation.

31 The water is maintained at a temperature of 19-21 0 C with a 32 dissolved oxygen concentration of at least 60% and a pH in 33 the range of 7.5-8.0. A photoperiod of 16 hours light per 34 24 hours is maintained, and the larvae are feed twice daily SUBSTITUTE SHEET WO 94/28994 PCT/US93/05820 1 with one drop of diluted brine shrimp that are less than 24- 2 hours old. The beaker is examined daily for four days 3 after the start of the test and the mortality recorded.

4 Dead larvae and bottom debris, if present, are removed using a medicine dropper.

6 7 By conducting a number of such tests using test solutions of 8 varying concentrations, one skilled in the art can determine 9 the LC 50 value of the test material.

SUBSTITUTE

SHEET

Claims (2)

1. A process for removing a toxicant from an aqueous waste stream associated with the production of petroleum or petroleum products wherein the toxicant is a thermally stable organic molecule having a molecular weight in the range from about 200 to about 400 and at least one carboxylic acid group, said toxic further having a

96-hour median lethal concentration for larval rainbow trout and larval fathead minnows of less than about ppb, said process comprising the steps of: contacting the waste stream with an activated non- ionic macroreticular polymeric resin having low to intermediate surface polarity for a time sufficient to reduce the amount of said toxicant in said waste stream to a preselected level, and recovering the waste stream from the resin with a reduced level of toxicity. 2. The process of claim 1 wherein the activated non-ionic macroreticular polymeric resin is a copolymer of styrene and divinylbenzene. 3. The process of claim 2 wherein the activated non-ionic macroreticular polymeric resin has a surface area in the range of about 300 to about 800 m /g and an average pore diameter of about 50 to about 90 A. 4. The pri'cess of claim 3 wherein the activated non-ionic macroreticular polymeric resin is AMBERLITE* XAD-2 or •AMBERLITEe XAD-4. eeoc *q ooo N O 94128994 PCT/US93/05820 -37- 1 5. The process of claim 1 wherein the activated non-ionic 2 macroreticular polime: resin is an essentially all 3 aliphatic polymer comprising about 2 to 100 weight 4 percent of a polyfunctional methacrylate contairing at least three mi'-nacrylate groups. 6 7 6. The process of claim 5 wherein the activated non-ionic 8 macroreticular polymeric resin has a surface area in 9 the range of about 100 to 400 m2/g and an average pore diameter of about 80 to about 250 A. 11 "2 7. The process of claim 6 wherein the polyfunctional 13 methacrylate is trimethylolpropane trimethacrylate. 14 8. The process of claim 6 wherein the activated non-ionic 16 macroreticular polymeric resin is AMBERLITE® XAD-7. 17 18 9. The process of claim 1 including the additional steps 19 of: 21 contacting the resin of step with fresh 22 activating solvent for a time sufficient to 23 reactivate the resin, 24 recovering the reactivated resin from the 26 activating solvent, and 27 28 using the reactivated resin of step as the 29 activated macroreticular polymeric resin used in carrying out step 31 32 10. The process of claim 9 whe.ein the activation solvent 33 is an organic solvent having a dielectric constant 34 greater than about SUBSTITUTE SHEET -38- 1 11. The process of claim 10 wherein the activation solvent 2 is methanol, ethanol, isopropanol, acetone, methyl 3 ethyl ketone, diethyl ether, ethyl acetate, 4 dichloromethae, chloroform, trichloroethane or mixtures thereof. 6 7 12. The prcsia of claim 11 wherein the activation solvent a is metaelQ. 9 13. A method of detecting a toxicant in an aqueous waste 11 stream, wherein said toxicant is a thermally stable 12 organic molecule having a molecular weight in% the range 13 from about 200 to about 400 and containing at least one 14 carboxylic acid group, said toxicant further having a 96-hour median lethal concentration for larval rairbow 16 trout and larval fathead minnows of less than 10 ppb, 17 said method comprising the steps of: 18 19 contacting the aqueous waste stream with an activated non-ionic macroreticular polymeric resin 21 having a low to intermediate surface polarity for 22 a time sufficient to adsorb a detectable-amount of 23 the toxicant on the resin; thereafter, 24 25 washing the resin with an extraction solvent under 26 conditions effective for the removal of organic 27 material from the resin to produce a resin extract 28 in the extraction solvent; and, 29 30 subjecting a sample of the resin extract to high 31 performance liquid chromatography under conditions 32 effective for detection of the toxicant. 34 33 *o -39- 14. The method of claim 13 comprising the additional steps of: removing non-toxic organic material from the resin extract of step by intimately contacting the resin extract in a partitioning solvent with water; thereafter, separating the partitioning solvent solution containing the resin extract from the water; and taking a sample of the resin extract from step (e) and subjecting said sample to a high performance of chromatography according to step of claim 13. 15. The method of claim 14 wherein the partitioning solvent is a chlorinated organic solvent. 16. The method of claim 15 wherein the partitioning solvent is dichloromethane. 17. The method of claim 13 wherein the aqueoils waste stream is associated with the production of petroleum or petroleum products. 18. The method of claim 13 wherein the activated non-ionic macroreticular polymeric resin is an essentially all aliphatic polymer comprising about 2 to 100 weight percent of a polyfunctional methacrylate containing at least three 30 methacrylate groups. 19. The method of claim 18 wherein the activated non-ionic macroreticular polymeric resin has a surface area in the range of about 100 to 400 m 2 /g and an average pore diameter of about 80 to about 250 A. 950809,p:\opdab,46397.spc,39 The method of claim 19 wherein the activated non-ionic macroreticular polymeric resin is AMBERLITE® XAD-7. 21. The method of claim 18 wherein the polyfunctional methacrylate is trimethylolpropane trimethacrylate. 22. The method of claim 13 wherein the extraction solvent is an organic solvent having a dielectric constant greater than about 23. The method of claim 22 wherein the extraction solvent is methanol, acetone, dichloromethane, chloroform, diethyl ether or ethyl acetate or mixtures thereof. 15 24. The method of claim 23 wherein the extraction solvent is methanol. o 25. The method of claim 13 wherein the high performance liquid chromatography is conducted using a reverse-phase column. 26. The method of claim 25 wherein the reverse-phase column is an octadecyl silane column. 25 27. The method of claim 26 wherein said column is first eluted using a linear triple solvent gradient consisting of water, acetonitrile and a dilute aqueous solution of acetic acid; and then purged with methanol. DATED this 10th day of August, 1995 Chevron Research and Technology Company By Its Patent Attorneys DAVIES COLLISON CAVE f -0 950809,p:\opAdab,46397.spc,40