A comparison of aggregation behavior in aqueous humic acids

Springer Science and Business Media LLC - Tập 2 - Trang 1-5 - 2001
Christi Young1, Ray von Wandruszka1
1Department of Chemistry, University of Idaho, Moscow, (USA)

Tóm tắt

The ability of six humic acids (HAs) to form pseudomicellar structures in aqueous solution was evaluated by five techniques: size exclusion chromatography; pyrene fluorescence enhancement; the pyrene I1/I3 ratio; the cloud point of dilute HA solutions; and the fluorescence anisotropy of HAs. Soil HAs were found to aggregate most easily, both on microscopic and macroscopic scales. The formation of amphiphilic structures was chiefly related to HA-solvent interactions: highly solvated HAs aggregated poorly, while a lignite derived material underwent intermolecular, rather than intramolecular, rearrangements. A newly discovered algal HA was found to have minimal aggregative properties.

Tài liệu tham khảo

Swift RS: Macromolecular properties of soil humic substances: fact, fiction, and opinion. Soil Sci. 1999, 164: 790-10.1097/00010694-199911000-00003. Thorn KA, Folan DW, MacCarthyn P: Characterization of the International Humic Substances Society Standard and Reference Fulvic and Humic Acids by Solution State Carbon-13 and Hydrogen-1 Nuclear Magnetic Resonance Spectrometry, Water Resources Investigations Report 89-4196. 1989, US Geological Survey, Denver, CO Anderson MA, Hung A, Mills D, Scott MS: Factors affecting the surface tension of soil solutions and solutions of humic acids. Soil Sci. 1995, 160: 111- Chiou CT, Malcolm RL, Brinton TI, Kile DE: Water solubility enhancement of some organic pollutants and pesticides by dissolved numic and luivic acids. Environ Sci Technol. 1986, 20: 502-10.1021/es00147a010. Larson RA, Rounds SA: Photochemistry in Aqueous Surface Layers. Photochemistry in Environmental Aquatic Systems. Edited by: Zika RG, Cooper WJ. 1987, American Chemical Society, Washington, DC Kile DE, Chiou CT: Water-Solubility Enhancement of Nonionic Organic Contaminants. Aquatic Humic Substances. Edited by: Suffet IH, MacCarthy P. 1989, American Chemical Society, Washington, DC Rochus W, Sipos S: Micelle formation by humic substances. Agrochimica. 1978, 22: 446- Wershaw RL: A new model for humic materials and their interactions with hydrophobic organic chemicals in soil-water or sediment-water systems. J Contam Hydrol. 1986, 1: 29-10.1016/0169-7722(86)90005-7. Wershaw RL: Membrane-micelle model for humus in soils and sediments and its relation to humification, Open file report 91-513. 1992, US Geological Survey, Denver, CO Wershaw RL: Environ Sci Technol. 1993, 27: 814-10.1021/es00042a603. Engebretson RR, von Wandruszka R: Microorganization in dissolved humic acids. Environ Sci Technol. 1994, 28: 1934-10.1021/es00060a026. Engebretson RR, von Wandruszka R: Kinetic aspects of cation-enhanced aggregation in aqueous humic acids. Environ Sci Technol. 1998, 32: 488-10.1021/es970693s. von Wandruszka R: The micellar model of humic acid: evidence from pyrene fluorescence measurements. Soil Sci. 1998, 163: 921-10.1097/00010694-199812000-00002. Yates LM, Engebretson RR, Haakenson TM, von Wandruszka R: Immobilization of aqueous pyrene by dissolved humic acid. Anal Chim Acta. 1997, 356: 295-10.1016/S0003-2670(97)00503-5. Engebretson RR, von Wandruszka R: The effect of molecular size on humic acid associations. Org Geochem. 1997, 26: 759-10.1016/S0146-6380(97)00057-0. von Wandruszka R, Ragle C, Engebretson RR: The role of selected cations in the formation of pseudomicelles in aqueous humic acid. Talanta. 1997, 44: 805-10.1016/S0039-9140(96)02116-9. Murphy EM, Zachara JM, Smith SC: Influence of mineral-bound humic substances on the sorption of hydrophobic organic compounds. Environ Sci Technol. 1990, 24: 1507-10.1021/es00080a009. Ames TT, Grulke EA: Group contribution method for predicting equilibria of nonionic organic compounds between soil organic matter and water. Environ Sci Technol. 1995, 29: 2273- Aochi YO, Farmer WJ: Role of microstructural properties in the time-dependent sorption/desorption behavior of 1,2-dichloroethane on humic substances. Environ Sci Technol. 1997, 31: 2420-10.1021/es960927s. Litton GM, Guymon GL: Laboratory experiments evaluating the transport and fate of DBCP in Hanford sandy loam. J Environ Qual. 1993, 22: 311- Magee BR, Lion LW, Lemley AT: Transport of dissolved organic macromolecules and their effect on the transport of phenanthrene in porous media. Environ Sci Technol. 1991, 25: 323-10.1021/es00014a017. Product literature published on January 25. 1985, International Humic Substances Society, St. Paul, MN Ghabbour EA, Khairy AH, Cheney DP, Gross V, Davies G, Gilbert TR, Zhang X: Isolation of humic acid from the brown alga. Pilayella littoralis J Appl Phycol. 1994, 6: 459-10.1007/BF02182399. Cameron RS, Swift RS, Thornton BK, Posner AM: Calibration of gel permeation chromatography materials for use with humic acid. J Soil Sci. 1972, 23: 342- Dong DC, Winnik MA: The py scale of solvent polarities. Solvent effects on the vibronic fine structure of pyrene fluorescence and empirical correlations with ET and Y values. Photochem Photobiol. 1982, 35: 1721- Hinze WL, Pramauro E: A critical review of surfactant-mediated phase separation (cloud point extraction): theory and applications. Crit Rev Anal Chem. 1993, 24: 133- Lackowicz JR: Principles of Fluorescence Spectroscopy. 1999, Kluwer Academic, New York, 291-316. 2