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Title: Effect of pH on adsorption of arsenic and selenium from landfill leachate by clay minerals

Effect of pH on adsorption of arsenic and selenium from landfill leachate by clay minerals Adsorption of As(V), As(III), and Se(IV) anions from municipal landfill leachate solutions by the clay minerals kaolinite and montmorillonite is strongly dependent upon solution pH. The H/sub 2/AsO/sub 4//sup -/ and HSeO/sub 3//sup -/ ions are the apparent primary As(V) and Se(IV) species being adsorbed by the clay minerals. Activation of the anion adsorption sites on the clay minerals by H/sup +/ ions is important in determining the amount of HSeO/sub 3//sup -/ ions adsorbed by the clay minerals, but it is apparently not important in determining the amount of H/sub 2/AsO/sub 4//sup -/ ions adsorbed. Montmorillonite adsorbed more As(V), As(III), and Se(IV) anions than kaolinite. Although no definite proof is given, the higher adsorption by montmorillonite is attributed to a higher edge surface area. The results of the study suggest that disposal of As and Se wastes in municipal landfills, especially under alkaline conditions, could produce ground water contamination by As and Se.
Authors: ;
Publication Date:
OSTI Identifier:OSTI ID: 7277277
Resource Type:Journal Article
Resource Relation:Journal Name: Soil Sci. Soc. Am. J.; (United States); Journal Volume: 41:1
Research Org:Illinois State Geological Survey, Urbana
Country of Publication:United States
Language:English
Subject: 54 ENVIRONMENTAL SCIENCES; ARSENIC; ADSORPTION; CLAYS; PH VALUE; SELENIUM; ANIONS; ARSENIC COMPOUNDS; ENVIRONMENTAL EFFECTS; GROUND WATER; IONS; KAOLINITE; LAND POLLUTION; LEACHING; MINERALS; MONTMORILLONITE; SANITARY LANDFILLS; SELENIUM COMPOUNDS; SOILS; WATER POLLUTION; ALUMINIUM COMPOUNDS; ALUMINIUM SILICATES; CHARGED PARTICLES; DISSOLUTION; ELEMENTS; HYDROGEN COMPOUNDS; INORGANIC ION EXCHANGERS; ION EXCHANGE MATERIALS; MANAGEMENT; OXYGEN COMPOUNDS; POLLUTION; SEMIMETALS; SEPARATION PROCESSES; SILICATES; SILICON COMPOUNDS; SORPTION; WASTE DISPOSAL; WASTE MANAGEMENT; WATER 510200* -- Environment, Terrestrial-- Chemicals Monitoring & Transport-- (-1989)