AUTHOR=Chen Wanting , Zhang Han , Liang Yu , Ding Hao , Sun Sijia TITLE=Adsorption Properties and Mechanism of Cd2+ in Water by Zr-containing Silica Residue Purification JOURNAL=Frontiers in Chemistry VOLUME=6 YEAR=2018 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2018.00556 DOI=10.3389/fchem.2018.00556 ISSN=2296-2646 ABSTRACT=

Zirconium (Zr)-containing silica residue purification (ZSR-P) discharged from industrial production of ZrOCl2 was used as an adsorbent, and CdCl2 solution was used as the simulated wastewater containing cadmium ions (Cd2+). The properties and mechanisms of ZSR-P absorbing Cd2+ were studied. The results showed that ZSR-P had a good effect on the adsorption and removal of Cd2+ in water. The adsorption time, initial concentration of Cd2+, and pH of the solution had a significant effect on the adsorption behavior, whilst the pH value had the greatest effect amongst them. Under optimal conditions, the amount of Cd2+ adsorbed by ZSR-P was 43.1 mg/g. The isothermal adsorption conformed to the Langmuir adsorption model, and the adsorption kinetics conformed to the secondary adsorption rate model. In ZSR-P-Cd, Cd2+ was uniformly distributed on the surface of SiO2 particles and in the pores formed by the accumulation of particles. Adsorption of Cd2+ by ZSR-P was achieved through the reaction between Si-OH on the surface of SiO2 and Cd2+ hydroxyl compounds.