Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-26T16:37:18.421Z Has data issue: false hasContentIssue false

Sorption of Nitroaromatics by Ammonium- and Organic Ammonium-Exchanged Smectite: Shifts from Adsorption/Complexation to a Partition-Dominated Process

Published online by Cambridge University Press:  01 January 2024

Michael G. Roberts
Affiliation:
Department of Crop and Soil Sciences, Environmental Science and Policy Program, Michigan State University, East Lansing, Michigan 48824-1325, USA
Hui Li
Affiliation:
Department of Crop and Soil Sciences, Environmental Science and Policy Program, Michigan State University, East Lansing, Michigan 48824-1325, USA
Brian J. Teppen
Affiliation:
Department of Crop and Soil Sciences, Environmental Science and Policy Program, Michigan State University, East Lansing, Michigan 48824-1325, USA
Stephen A. Boyd*
Affiliation:
Department of Crop and Soil Sciences, Environmental Science and Policy Program, Michigan State University, East Lansing, Michigan 48824-1325, USA
*
*E-mail address of corresponding author: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Nitroaromatic compounds (NACs) are components of munitions commonly found as soil contaminants at military training sites and elsewhere. These compounds pose possible threats to human health and ecological systems. Recent studies indicate that these compounds are strongly retained by smectite clays. The adsorption mechanisms are not fully reconciled, but it is known that the type of exchangeable cation strongly affects NAC affinity for smectites. This study examined the sorption of 1,3-dinitrobenzene, 2,4-dinitrotoluene and naphthalene from water by a smectite clay (SWy-2) saturated with ammonium, tetramethylammonium (TMA), trimethylphenylammonium (TMPA) and hexadecyltrimethylammonium (HDTMA). In all cases, we observed greater sorption of 2,4-dinitrotoluene compared with 1,3-dinitrobenzene. The sorption isotherms for 2,4-dinitrotoluene and 1,3-dinitrobenzene displayed a concave-downward curve for NH4-SWy-2 and TMA-SWy-2, whereas the isotherms for sorption of HDTMA-SWy-2 and TMPA-SWy-2 were essentially linear. The magnitude of sorption followed the order: NH4-SWy-2 > TMA-SWy-2 > TMPA-SWy-2 > HDTMA-SWy-2 for both compounds. The greater affinity of NACs for NH4- and TMA-SWy-2 is due in part to complex formation between the exchangeable cation and −NO2 groups. These clays also provide near optimal interlayer distances that approximate the molecular thickness of NACs hence promoting the simultaneous interaction of the planar aromatic rings with opposing siloxane surfaces and solute dehydration. Both processes are energetically favorable. In HDTMA-SWy-2, sorption of all solutes is via a partition-dominated process. Solute competition (diminished uptake of one solute in the presence of a second) was observed for TMA-SWy-2 but not HDTMA-SWy-2. This is consistent with an adsorptive mechanism for TMA-SWy-2 and a partitioning mechanism for HDTMA-SWy-2. This study demonstrates that the dominant molecular mechanism of NAC sorption by smectite changes fundamentally from complexation between −NO2 groups and the exchangeable cation (viz. NH4 and TMA) to partitioning for a systematic series of ammonium and quaternary ammonium cations in which the locus of positive charge (the central N atom) is progressively shielded by organic moieties of increasing size.

Type
Research Article
Copyright
Copyright © 2006, The Clay Minerals Society

References

Barrer, R.M. and Perry, G. S. (1961) Sorption of mixtures, and selectivity in alkylammonium montmorillonite. Part II. Tetramethylammonium montmorillonite: Journal of Chemistry Society, 850858.Google Scholar
Boyd, S.A. Lee, J.F. and Mortland, M.M., (1988) Attenuating organic contaminant mobility by soil modification Nature 333 345347 10.1038/333345a0.CrossRefGoogle Scholar
Boyd, S.A. Mortland, M.M. and Chiou, C.T., (1988) Sorption characteristics of organic compounds on hexadecyltrimethylammonium-smectite Soil Science Society of America Journal 52 652657 10.2136/sssaj1988.03615995005200030010x.CrossRefGoogle Scholar
Boyd, S.A. Sheng, G. Teppen, B.J. and Johnston, C.T., (2001) Mechanisms for the adsorption of substituted nitrobenzenes by smectite clays Environmental Science and Technology 35 42274234 10.1021/es010663w.CrossRefGoogle ScholarPubMed
Burris, D.R. and Anthworth, C.P., (1992) In situ modification of aquifer material by a cationic surfactant to enhance retardation of organic contaminants Journal of Contaminant Hydrology 10 325337 10.1016/0169-7722(92)90014-6.CrossRefGoogle Scholar
Chiou, C.T., (2002) Partition and Adsorption of Organic Contaminants in Environmental Systems Hoboken, New Jersey John Wiley & Sons, Inc. 10.1002/0471264326.CrossRefGoogle Scholar
Ford, G.P. and Wang, B., (1992) The optimized ellipsoidal cavity and its application to the self-consistent reaction field calculation of hydration energies of cations and neutral molecules Journal of Computation Chemistry 13 229239 10.1002/jcc.540130214.CrossRefGoogle Scholar
Haderlein, S.B. and Schwarzenbach, R.P., (1993) Adsorption of substituted nitrobenzenes and nitrophenols to mineral surfaces Environmental Science and Technology 27 316326 10.1021/es00039a012.CrossRefGoogle Scholar
Haderlein, S.B. Weissmahr, K.W. and Schwarzenbach, R.P., (1996) Specific adsorption of nitroaromatic explosives and pesticides to clay minerals Environmental Science and Technology 30 612622 10.1021/es9503701.CrossRefGoogle Scholar
Hundal, L.S. Thompson, M.L. Laird, D.A. and Carmo, A.M., (2001) Sorption of phenanthrene by reference smectites Environmental Science and Technology 35 34563461 10.1021/es001982a.CrossRefGoogle ScholarPubMed
Jaynes, W.F. and Boyd, S.A., (1990) Trimethylphenylammonium-smectite as an effective adsorbent of water-soluble aromatic hydrocarbons Journal of Air and Waste Management Association 40 16491653 10.1080/10473289.1990.10466811.CrossRefGoogle ScholarPubMed
Jaynes, W.F. and Boyd, S.A., (1991) Clay mineral type and organic compound sorption by hexadecyltrimethylammonium-exchanged clays Soil Science Society of America Journal 55 4348 10.2136/sssaj1991.03615995005500010007x.CrossRefGoogle Scholar
Jaynes, W.F. and Boyd, S.A., (1991) Hydrophobicity of siloxane surfaces in smectites as revealed by aromatic hydrocarbon adsorption from water Clays and Clay Minerals 39 428436 10.1346/CCMN.1991.0390412.CrossRefGoogle Scholar
Johnston, C.T. de Oliveria, M.F. Teppen, B.J. Sheng, G. and Boyd, S.A., (2001) Spectroscopic study of nitroaromatic-smectite sorption mechanisms Environmental Science and Technology 35 47674772 10.1021/es010909x.CrossRefGoogle ScholarPubMed
Johnston, C.T. Sheng, G. Teppen, B.J. Boyd, S.A. and Oliveira, M.F.d., (2002) Spectroscopic study of dinitrophenol herbicide sorption on smectite Environmental Science and Technology 36 50675074 10.1021/es025760j.CrossRefGoogle ScholarPubMed
Lee, J.F. Crum, J.R. and Boyd, S.A., (1989) Enhanced retention of organic contaminants by soils exchanged with organic cations Environmental Science and Technology 23 13651372 10.1021/es00069a006.CrossRefGoogle Scholar
Lee, J.F. Mortland, M.M. Chiou, C.T. Kile, D.E. and Boyd, S.A., (1990) Adsorption of benzene, toluene, and xylene by two tetramethylammonium-smectites having different charge densities Clays and Clay Minerals 38 113120 10.1346/CCMN.1990.0380201.CrossRefGoogle Scholar
Li, H. Teppen, B.J. Laird, D.A. Johnston, C.T. and Boyd, S.A., (2004) Geochemical modulation of pesticide sorption on smectite clay Environmental Science and Technology 38 53935399 10.1021/es0494555.CrossRefGoogle ScholarPubMed
Li, H. Teppen, B.J. Johnston, C.T. and Boyd, S.A., (2004) Thermodynamics of nitroaromatic compounds adsorption from water by smectite clay Environmental Science and Technology 38 54335442 10.1021/es035054y.CrossRefGoogle ScholarPubMed
Marcus, Y., (1985) Thermodynamic functions of transfer of single ions from water to nonaqueous and mixed-solvents. 2. Enthalpies and entropies of transfer to nonaqueous solvents Pure and Applied Chemistry 57 11031128 10.1351/pac198557081103.CrossRefGoogle Scholar
McBride, M.B. Pinnavaia, T.J. Mortland, M.M. and Suffet, I.H., (1977) Adsorption of aromatic molecules by clays in aqueous suspension Fate of Pollutants in the Air and Water Environment. Part 1 New York Wiley-Interscience 145154.Google Scholar
Mortland, M.M. Sun, S. and Boyd, S.A., (1986) Clay-organic complexes as adsorbents for phenol and chlorophenols Clays and Clay Minerals 34 581585 10.1346/CCMN.1986.0340512.CrossRefGoogle Scholar
Sheng, G. Xu, S. and Boyd, S.A., (1996) Mechanism(s) controlling sorption of neutral organic contaminants by surfactant-derived and natural organic matter Environmental Science and Technology 30 15531557 10.1021/es9505208.CrossRefGoogle Scholar
Sheng, G. Wang, X. Wu, S. and Boyd, S.A., (1998) Enhanced sorption of organic contaminants by smectitic soils modified with a cationic surfactant Journal of Environmental Quality 27 806814 10.2134/jeq1998.00472425002700040013x.CrossRefGoogle Scholar
Sheng, G. Johnston, C.T. Teppen, B.J. and Boyd, S.A., (2002) Adsorption of dinitrophenol herbicides from water by montmorillonites Clays and Clay Minerals 50 2534 10.1346/000986002761002630.CrossRefGoogle Scholar
Van Olphen, H. and Fripiat, J.J., (1979) Data Handbook for Clay Minerals and other Non-metallic Minerals New York Pergamon Press.Google Scholar
Weissmahr, K.W. Haderlein, S.B. and Schwarzenbach, R.P., (1998) Complex formation of soil minerals with nitroaromatic explosives and other pi-acceptors Soil Science Society of America Journal 62 369378 10.2136/sssaj1998.03615995006200020012x.CrossRefGoogle Scholar
Weissmahr, K.W. Hildenbrand, M. Schwarzenbach, R.P. and Haderlein, S.B., (1999) Laboratory and field scale evaluation of geochemical controls on groundwater transport of nitroaromatic ammunition residues Environmental Science and Technology 33 25932600 10.1021/es981107d.CrossRefGoogle Scholar
Wolfe, T.A. Demerirel, T. and Baumann, E.R., (1985) Interaction of aliphatic amines with montmorillonite to enhance adsorption of organic pollutants Clays and Clay Minerals 33 301311 10.1346/CCMN.1985.0330405.CrossRefGoogle Scholar
Xu, S. and Boyd, S.A., (1995) Cationic surfactant adsorption by swelling and nonswelling layer silicates Langmuir 11 25082514 10.1021/la00007a033.CrossRefGoogle Scholar
Xu, S. Sheng, G. and Boyd, S.A., (1997) Use of organoclays in pollution abatement Advances in Agronomy 59 2561 10.1016/S0065-2113(08)60052-8.CrossRefGoogle Scholar
Zhu, D. Herbert, B.E. Schlautman, M.A. Carraway, E.R. and Hur, J., (2004) Cation-π bonding: a new perspective on the sorption of polycyclic aromatic hydrocarbons to mineral surfaces Journal of Environmental Quality 33 13221330 10.2134/jeq2004.1322.CrossRefGoogle ScholarPubMed