title: Predicting competitive adsorption behavior of major toxic anionic elements onto activated alumina: a speciation-based approach.
abstract: Toxic anionic elements such as arsenic, selenium, and vanadium often co-exist in groundwater. These elements may impact each other when adsorption methods are used to remove them. In this study, we investigated the competitive adsorption behavior of As(V), Se(IV), and V(V) onto activated alumina under different pH and surface loading conditions. Results indicated that these anionic elements interfered with each other during adsorption. A speciation-based model was developed to quantify the competitive adsorption behavior of these elements. This model could predict the adsorption data well over the pH range of 1.5-12 for various surface loading conditions, using the same set of adsorption constants obtained from single-sorbate systems. This model has great implications in accurately predicting the field capacity of activated alumina under various local water quality conditions when multiple competitive anionic elements are present.
authors.affiliation: Department of Civil, Architectural and Environmental Engineering, Missouri University of Science and Technology, 1870 Miner Circle, Rolla, MO 65401, USA.
authors.forename: Tingzhi
authors.initials: T
authors.lastname: Su
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Guan
authors.forename: Yulin
authors.initials: Y
authors.lastname: Tang
authors.forename: Guowei
authors.initials: G
authors.lastname: Gu
authors.forename: Jianmin
authors.initials: J
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry*; D000838:Anions; D001151:Arsenic / Q000302:isolation & purification; D001667:Binding, Competitive; D015386:Hazardous Substances / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D012643:Selenium / Q000302:isolation & purification; D014639:Vanadium / Q000302:isolation & purification; D018508:Water Purification / Q000379:methods*
chemical_list: D000838:Anions; D015386:Hazardous Substances; D014639:Vanadium; D012643:Selenium; D000537:Aluminum Oxide; D001151:Arsenic