RES³T - Rossendorf Expert System for Surface and Sorption Thermodynamics

Paper Details


Bibliographic Data:

Code: WTWAP03
Paper Type: Article
Author(s): Weerasooriya R, Tobschall HJ, Wijesekara HKDK, Arachchige EKIAUK, Pathirathne KAS
Title: On the mechanistic modeling of As(III) adsorption on gibbsite
Journal: Chemosphere
Volume: 51   Year: 2003   Pages: 1001-1013
ISSN-Print: 0045-6535
Internal Storage: V3760
DOI: 10.1016/S0045-6535(03)00157-7
Abstract:

Arsenite adsorption on gibbsite was examined as a function of pH, ionic strength (I) and contact time (tC). As(III) showed a weak affinity for gibbsite surface. The trends of pH=f(Γads) curves have showed a marked deviation from a typical anion adsorption edge showing a maximum Γads around pH∼8.2. The experimentally derived proton exchange ratio has always converged to zero when 0.26<∑[As(III)]<7 μM and 6.2<pH<8.2. The isosteric heat of adsorption, ΔHr, exhibited invariant behavior with respect to Γads. The As(III) adsorption data was quantified by charge distribution multi-site complexation (CD MUSIC) model using the surface complex postulated below:


Surface Area   |   Site Density / Protolysis   |   Complex Formation   |   Formatted Citation