Factors modifying the structural configuration of oxyanions and organic acids adsorbed on iron (hydr)oxides in soils. A review
Year: 2020
Type: article
Abstract: Oxyanions are ubiquitous in soils, organisms and the environment. Due to their unique chemical structure, oxyanions can be easily transferred into other systems. Carbonate (CO32−), nitrate (NO3−), phosphate (PO43−), silicate (SiO42−) and sulfate (SO42−) are the major oxyanions in organisms and the soil environment, whereas arsenate (AsO43−), antimonate (SbO43−), borate (BO33−), selenate (SeO42−), and tellurate (TeO42−) are generally reported as toxic chemicals found at trace levels. Excessive oxyanions leached from soils into water have caused severe environmental problems. Here, we review the factors affecting the structural configuration of oxyanions and organic acids adsorbed on iron oxides and hydroxides. The configuration of oxyanions on iron (hydr)oxides is controlled by surface loading, pH, sample phase, competing ions and organic acids. Under conditions of low surface loading and low pH at the interface in the absence of competing ions, oxyanions with high affinity possibly form a complex with higher denticity. But an increase in pH decreases the number of sorption sites; thus, a transition from a tri- or bidentate complex to monodentate and outer-sphere complexes occurs.
Source: Environmental Chemistry Letters
Authors: Junho Han, Minhee Kim, Hee-Myong Ro
Institutions: Seoul National University, Ministry of Environment
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,860
OpenAlex ID: W3006138914