title: Macroscopic and vibration spectroscopic evidence for specific bonding of arsenate on gibbsite.
abstract: The As(V) adsorption onto gibbsite under different experimental conditions was examined. Macroscopic data suggests strong As(V) bonding on gibbsite possibly via a bidendate binuclear complexation mechanism. The As(V) adsorption was quantified with the charge distribution multi-site ions complexation (CD-MUSIC) model distributing the anion charge over 0- and 1-planes according to the modified Pauling's bond valence theory. In the dual-adsorbates system of As(III) and As(V), the As(III) adsorption was predicted up to pH 8 utilizing the binding constants derived for single-adsorbate data. However, with pH > 8, the modeled As(III) adsorption data is overestimating the experimental values.
authors.affiliation: Lehrstuhl für Angewandte Geologie, Universität Erlangen-Nürnberg, Schlossgarten 5, 91054 Erlangen, Germany. rohan@geol.uni-erlangen.de, rweerasooriya@hotmail.com
authors.forename: R
authors.initials: R
authors.lastname: Weerasooriya
authors.forename: H J
authors.initials: HJ
authors.lastname: Tobschall
authors.forename: H K D K
authors.initials: HK
authors.lastname: Wijesekara
authors.forename: A
authors.initials: A
authors.lastname: Bandara
mesh_terms: D000327:Adsorption; D000536:Aluminum Hydroxide / Q000737:chemistry*; D001149:Arsenates / Q000737:chemistry*; D002849:Chromatography, Gas; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008956:Models, Chemical; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001149:Arsenates; D000536:Aluminum Hydroxide; C025657:arsenic acid