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appears to be rather reactive in acetone solution as well. AS determined in our laboratory, Table IV demonstrates that anthracene-dlo is slowly degraded in acetone solution, with 9,lO-anthracenedione-d8 formed concurrently with that degradation. The other compounds in Table IV, including benzo[a]pyrene, remain at or near the 100 ng/pL level. The lack of 1:l correspondence between the losses in anthracene-dlo and the resultant formation of 9,lO-anthracenedione-d8 may be the result of the formation of oxidation products other than the dione. Unlike the peroxide/Florisil oxidation, this process was only observed in the solution which was exposed to light. The data indicate a first-order decay rate law [anthracene-dlo] = [anthracene-dloloexp(-kt) with rate constant It = 2.3 X h-l. This rate is substantially slower than the degradation which occurred during cleanup with 5050 pentane:diethyl ether/Florisil, although certainly faster than observed in the pentane:ether solutions. Though there were no papers in the literature dealing with losses of PAHs in ether solvents with or without cleanup, it seemed likely that some pertinent, but unpublished information existed. Therefore, as a final step in this study, over 30 analysts involved in the area of PAH analysis were contacted and requested to comment on the above observations. Of the ten replies received eight had no personal experience with PAHs in diethyl ether; four suggested the possibility of incomplete elution from the cleanup column (the above data has ruled that out for this work); three suggested losses due to peroxides; one reported 80-100% recoveries from silica gel for microgram quantities of anthracene as well as a number of other PAHs (acenaphthylene was not included) from EM60 silica gel activated at 130 “C using 75:25 hexane:diethyl ether; and one reported 83-87 h3% recoveries for benzo[ghi]perylene, indeno[l72,3-cd1pyrene,benzo[a]pyrene, benzo[k]fluoranthene, and perylene from silica gel with pure diethyl ether. The fact that good recoveries of anthracene and benzo[a]pyrene were obtained with ether mixtures could be interpreted in terms of negligible levels of peroxides in those ethers. CONCLUSIONS When care is taken to use diethyl ether low in peroxides, the Florisil/diethyl ether cleanup procedure will allow the recovery of a wide range of neutral compounds while still eliminating polar compounds which hamper analysis by gas chromatography. Diethyl ether containing peroxides may be
used if the peroxides are first removed a method such as that of Warner (13)which involves the passage of ether through an alumina column may be used. ACKNOWLEDGMENT The authors express their appreciation to W. Bertsch, G. A. Junk, L. H. Keith, M. L. Lee, D. Rondia, L. M. Smith, and K. Van Cauwenberghe for their detailed reponses to our survey on PAH analytical schemes involving diethyl ether. Registry No. Anthracene, 120-12-7;acenaphthylene, 208-96-8; benzo[a]pyrene, 50-32-8; diethyl ether, 60-29-7. LITERATURE CITED Picer, M.; Ahel, A. J. Chromatogr. 1078, 150, 119. Snyder, D.; Reinert, R. Bull. fnvlron. Contam. Toxlcol. 1071. 6, 385. Research Triangle Institute ”Master Scheme for the Analysis of Organic Compounds in Water-Interim Protocols”, 1980. US. Environmental Protection Agency, “Method 608”. Test Methods; Longbottom, J. E., Lichtenberg, J. J., Eds.; EPA Document 60014-82057, 1982. US. Environmental Protection Agency, “Method 610”, Test Methods; Longbotton, J. E., Lichtenberg, J. J., Eds.; EPA Document 600/4-82057, 1982. Fox, M. A.; Olive, S. Science 1070, 205, 582. Korfmacher, W. A.; Natusch, D. F. S.;Taylor, D. R.; Mamantov, G.; Wehry, E. L. Science 1080, 207, 763. Korfmacher, W. A.; Mamantov, G.; Wehry, E. L.; Natusch, D. F. S.; Mauney. T. fnvlron. Scl. Technol. 1081, 15, 1370. Dunn, J. R.; Waters, W. A.; Roitt, I . M. J. Chem. SOC. 1054, 580. Pierce, R. C.; Katz, M. fnvlron. Scl. Technol. 1076, 10, 45. Pankow, J. F.; Isabelle, L. M.; Asher, W. E.; Kristensen, T. J.; Peterson, M. E. I n “Proc. 4th Int. Conf. Precipitation Scavenging, Dry Deposition, and Resuspension”; Pruppacher, H. R., Semonin, R. G., Slinn, W. G. N., Coordinators; Eisevier-North Holland New York, 1983. Konig, J.; Balfanz, E.; Funcke, W.; Romanowski, T. Anal. Chem. 1083, 55, 599. Warner, J. S. Anal. Chem. 1078, 48, 578.
Mary E. Ligocki James F. Pankow* Department of Chemical, Biological, and Environmental Sciences Oregon Graduate Center 19600 N. W. Walker Rd. Beaverton, Oregon 97006
RECEIVED for review January 19, 1984. Accepted August 2, 1984. This work was funded in part with federal funds from the United States Environmental Protection Agency (US EPA) under Grant No. R8113380. The contents do not necessarily reflect the views or policies of the US EPA, nor does mention of trade names or commercial products constitute endorsement or recommendation for use.
Determination of Total Organic Chloride in Solid Waste Sir: Chlorinated hydrocarbons are well-known for their toxicity and resistance to decomposition. Their presence in solid wastes may limit disposal or treatment options. For example, the US EPA has proposed a limit of 10 pg/g polychlorinated biphenyls in municipal sewage sludges which may be treated by surface application on agricultural land (1). Since the analysis of solid wastes for chlorinated hydrocarbons using highly specific techniques such as GC/MS is complex and costly, screening techniques for total organic chloride (TOCl) have been developed. A procedure has been described in which solid waste is Soxhlet extracted with benzene, the extract concentrated, and TOCl determined by short-column GC using a Hall electrolylic conductivity detedor (2). We have found, however, that gas chromatographic techniques may greatly underestimate the TOCl in some solid wastes. 0003-2700/84/0356-2987$01.50/0
This correspondence describes the measurement of TOCl in sludge collected at a kraft pulp mill wastewater treatment facility. TOCl was determined as the difference between the total chloride in the residue after ashing in a bomb calorimeter and the chloride extractable from the sludge with 0.1 M NaN03. These results were compared with those obtained by HRGC/MS of a methylene chloride extract. EXPERIMENTAL SECTION A sample of combined primary and secondary sludge was collected from the dewatering press at the wastewater treatment facility of a kraft pulp mill. Chlorine bleaching is used at the mill to whiten pulp. In a typical total chloride analysis, an aliquot of wet sludge (40% solids) sufficient to yield approximately 1g (oven dry weight) was dried to constant weight in a nickel crucible at 70 “C.The sludge was then wet with 250 p L of distilled deionized water and 0 1984 American Chemical Society
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Anal. Chem. 1984, 56,2988-2990
Table I. TOCl in Sludgea
total chlorideb extractable chloride' TOCl
n
X
9
5 3
2340 360 1980
160 80 180
Milligrams per kilogram (oven dry weight). sludge. In 0.1 M NaN03.
In combusted
combusted under 30 atm of oxygen in a Paar stainless steel bomb containing 5.0 mL of 5% (w/v) sodium carbonate. The residue was rinsed into a volumetric flask with distilled deionized water and diluted to 100 mL. To extract the inorganic chloride the moisture content of an aliquot of the wet sludge was adjusted to 900% with distilled deionized water. Sufficient sodium nitrate was added so that its concentration in water was 0.1 M. The mixture was then blended for 10 min in a Waring Deluxe Model blender operated at its highest speed. The extracting solution was separated from the solids by centrifugation at 8000g and decanted for chloride analysis. The chloride was measured in the combustate and in the 0.1 M NaN03 extract with an Orion Model 9417B chloride electrode by using the method of standard addition. An aliquot of the sludge was also spiked with pentafluorophenol, phenol-d6, and naphthalene-d8at the rate of 100 wg/g, blended with acidified anhydrous sodium sulfate, and Soxhlet extracted with methylene chloride for 16 h. The extract was concentrated and analyzed by HRGC/MS using a Hewlett-Packard Model 5992 equipped with an Ultra No. 1 (Hewlett-Packard) fused silica column (25 m X 0.33 mm i.d.). The column was temperature programmed from 40 to 270 "C at 8 OC/min with initial and final hold times of 2 and 20 min, respectively. The helium carrier gas flow rate was set at 5 mL/min. A "splitless" injection technique was used. The Soxhlet apparatus and the volumetric glassware were thoroughly rinsed with methanol and methylene chloride prior to use. All other glassware and the sodium sulfate were heated at 400 O C for 2 h prior to use. The methylene chloride used was Baker pesticide residue analysis grade. The spiking compounds were obtained from Aldrich. Reagent blanks were tested in each set of analyses.
RESULTS AND DISCUSSION The results of the TOCl analysis of replicate subsamples of the sludge are reported in Table I. TOCl was determined as the difference between the total chloride after combustion and the extractable chloride.
Notably no halogenated hydrocarbons were detected in the HRGC/MS analysis at an estimated method detection limit of 10 mg/kg (oven dry weight) for pentachlorophenol. The recovery of the spiking compounds was 115%, 19%, and 25% for the naphthalene-da, phenol-d,, and pentafluorophenol, respectively. The chlorinated organic compounds in this waste were not detectable using gas chromatographic conditions similar to those described by Nulton et al. for HRGC/MS analysis of benzene extrack of solid waste (2). Similar HRGC conditions have also been described for the analysis of the semivolatile organic priority pollutants ( 3 ) . The identity of the chlorinated organics is unknown; however, it is likely that they are relatively high molecular weight products of lignin chlorination. Lindstrom et al. have found, for example, that 95% of the TOCl in the effluent of the "E" stage in a pulp mill bleachery was in a molecular weight range greater than lo00 (4). Fifty-five percent was in a range greater than 25000. The molecular weight range was assigned by ultrafiltration and TOCl measured by oxygen bomb combustion. They also found that chemical degradation of the chlorinated organic compounds with potassium permanganate and sodium periodate in an alkaline medium yielded chlorinated guaiacols, catechols, phenols, and related compounds.
ACKNOWLEDGMENT I thank Stanley Johnson for performing the TOCl analyses. This work was performed while I was employed by the State of Maine, Department of Environmental Protection. Registry No. Chlorine, 7782-50-5.
LITERATURE CITED (1) Fed. R8gkt. 1979, 44, 179. (2) Nulton, C. P.; Haile, C. L.; Redford, D. P. Anal. Chem. 1984, 56, 598-599. .._ ...
(3) Sauter, A. D.; Betowski, L. D.;Smith, T. R.; Strlckler, V. A.; Belmer, R. G.; Colby, 8. N.; Wliklnson, J. E. HRC CC, J . H@h Resolut. Chromatogr. Chromatogr. Commun. 1981, 4 , 366-384. (4) Llndstrom, K.; Nordin, J.; Osterburg, F. I n "Advances in the Identification and Analysis of Organlc Pollutants in Water"; Keith, L. H., Ed.; Ann Arbor Science: Ann Arbor, MI, 1981; Vol. 2, pp 1039-1056.
Thomas L. Potter State of Maine Department of Environmental Protection Augusta, Maine 04333 RECEIVEDfor review May 25,1984. Accepted August 3,1984.
T * -Dipolarity
Numbers and a-Scale Acidities of Some Strong Hydrogen Bond Donor Solvents
Sir: An important analytical dimension to the separation and the determination of ionic species using equilibria in a nonaqueous medium is the choice of suitable parameters for the quantitative specification of the characteristics of the solvent itself. Of the several phenomenological scales measuring solvent properties, the Kamlet-Taft "linear solvation energy relationship" (the linear free-energy function in eq 1) has been more successful in correlating solvent effects among a wide range of chromatographic and kinetic equilibria as well as resolving the influences on the more fundamental thermodynamic and spectral quantitites for solutes in nonaqueous media (1). In this system the magnitude of the observable P = Po s(a* d6) aa + bp (1)
+
+
+
P is determined by these major properties of the solvent: the
hydrogen bond donor acidity (a), the hydrogen bond acceptor basicity (B), and the dipolarity of the solvent molecule ( r * ) . The d6 term is a solvent polarizability correction having a nonzero value for polyhalogenated alkanes and aromatics ( I ) . The preceding segments in this series of investigations have dealt with the analytical validity of the Kamlet-Taft parameters when applied to the electrochemical and solvatochromic behavior of organometallic species in differing nonaqueous solvents (2,3) as well as with the development of new probes for the measurement of solvent dipolarities (4-6). Among the latter, it was demonstrated that the nitrogen-15 NMR shifts for benzonitrile could be used effectively to evaluate both the a* and a parameters for moderate-to-weak hydrogen bonding solvents (6). The objectives of the present communication are twofold to report the extension of the previous techniques
0003-2700/84/0356-2988$01.50/00 1984 Amerlcan Chemical Soclety
