Author:
Zhao Dandan,Yang Yi,Chen J. Paul
Abstract
The studies on materials for decontamination in aqueous solutions have increasingly received greater attentions. Such contaminants as heavy metals, arsenic, fluoride and phosphate are harmful to humans and aqueous species due to higher toxicity. Zirconium based adsorbents have become more attractive due to outstanding performance in decontamination. This article provides a comprehensive review of the performance and mechanisms of five types adsorbents: zirconium (hydro)oxides, zirconium hydrogen sulfate, zirconium based multiple metal typed adsorbents and zirconium impregnated complexes. The pseudo-first order and pseudo-second order equations and the intraparticle diffusion model can be applied in describing the adsorption kinetics, while Langmuir and Freundlich equations are the most commonly used adsorption isotherms. The important mechanisms for uptake of contaminants are: ligand exchange between adsorbate and adsorbent, surface complexation formation, and Lewis acid–base and electrostatic interactions. A series of successful studies demonstrate that the adsorbents are promising for removing aqueous contaminants.