Facile synthesis of boehmite/PVA composite membrane with enhanced adsorption performance towards Cr(VI)

Lei Luo; Weiquan Cai; Jiabin Zhou; Yuanzhi Li

doi:10.1016/j.jhazmat.2016.07.019

Facile synthesis of boehmite/PVA composite membrane with enhanced adsorption performance towards Cr(VI)

J Hazard Mater. 2016 Nov 15:318:452-459. doi: 10.1016/j.jhazmat.2016.07.019. Epub 2016 Jul 7.

Authors

Lei Luo¹, Weiquan Cai², Jiabin Zhou³, Yuanzhi Li¹

Affiliations

¹ School of Chemistry, Chemical Engineering and Life Sciences, State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 205 Luoshi Road, Wuhan 430070, PR China.
² School of Chemistry, Chemical Engineering and Life Sciences, State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 205 Luoshi Road, Wuhan 430070, PR China. Electronic address: caiwq@whut.edu.cn.
³ School of Resources and Environmental Engineering, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070, PR China.

PMID: 27450337
DOI: 10.1016/j.jhazmat.2016.07.019

Abstract

A novel boehmite/PVA composite membrane (BPCM) with remarkably enhanced adsorption performance towards Cr(VI) was successfully synthesized from Al(NO3)3·9H2O using HAc as the peptizing agent via a facile sol-gel method. The physicochemical properties of the BPCM, the boehmite powder (BP) without PVA and a commercial boehmite powder (CBP) were comparatively characterized by XRD, TGA-DSC, FT-IR and XPS. Batch adsorption experiments showed that the adsorption performance of the BPCM is much better than those of BP and CBP. Its adsorption process was well described by the pseudo-second-order kinetic model, and its equilibrium data fit the Langmuir isotherm well with a maximum adsorption capacity of 36.41mgg(-1). Its interference adsorption experiment in presence of coexisting anions showed that SO4(2-) and HPO4(2-) have greater effect than those of the Cl(-), F(-), C2O4(2-) and HCO3(-). A three step action mechanism including adsorption of Cr(VI) anions, complexation between Cr(VI) anions and the functional groups on the surface of BPCM, and the reduction of Cr(VI) to Cr(III) was proposed to illustrate the adsorption process. This efficient film could be easily separated after adsorption, exhibiting great potential for the removal of Cr(VI) from aqueous solution, and other fields of environmental remediation.

Keywords: Adsorption mechanism; Boehmite/PVA composite membrane; Coexisting anions; Cr(VI) adsorption; Sol-gel method.