Journal
JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM
Volume 762, Issue 1-3, Pages 17-23Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.theochem.2005.08.038
Keywords
gibbsite; arsenic; As(III); H3AsO3; adsorption; DFT; cluster model
Categories
Ask authors/readers for more resources
It is well known that As(III) has a higher mobility compared to As(V) in the environment. This fact is explained by the high reversibility of As(III) adsorption on minerals such as Al (hydr)oxides. Nevertheless, experimental results pointed out that adsorption of As(III) leads to innersphere complexes, which appears to be in conflict with the high mobility of these species as inner-sphere complexes should be strongly attached. In this work we used density functional methods and cluster models to study two different mechanisms for the H3AsO3 adsorption on gibbsite-gamma-Al(OH)(3), one of the most abundant aluminum hydroxide minerals. Our results show that, differently from the As(V) case, As(III) is not adsorbed via an acid/base. but by a non-dissociative mechanism in which O-H bonds are not being broken. This non-dissociative mechanism also conciliates the hi-h remobilization of As(III) with the apparently inconsistent formation of inner-sphere adsorption complexes. (c) 2005 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available