Preparation and Characterization of Chitosan Thin Films on Mixed‐Matrix Membranes for Complete Removal of Chromium

ChemistryOpen

Vignesh Nayak¹  Mannekote Shivanna Jyothi¹  Prof. R. Geetha Balakrishna²  Dr. Mahesh Padaki³ 

[1] Center for Nano and Material Sciences, Jain University, Ramanagaram, Bangalore, India;E-mail address: E-mail address: 关键词: chitosan;    chromium;    composite membranes;    hydrophilicity;    reduction;   

DOI  :  10.1002/open.201402133

来源: Wiley

【 摘 要 】

Abstract

Herein we present a new approach for the complete removal of Cr^VI species, through reduction of Cr^VI to Cr^III, followed by adsorption of Cr^III. Reduction of chromium from water is an important challenge, as Cr^IV is one of the most toxic substances emitted from industrial processes. Chitosan (CS) thin films were developed on plain polysulfone (PSf) and PSf/TiO₂ membrane substrates by a temperature-induced technique using polyvinyl alcohol as a binder. Structure property elucidation was carried out by X-ray diffraction, microscopy, spectroscopy, contact angle measurement, and water uptake studies. The increase in hydrophilicity followed the order: PSf < PSf/TiO₂ < PSf/TiO₂/CS membranes. Use of this thin-film composite membrane for chromium removal was investigated with regards to the effects of light and pH. The observations reveal 100 % reduction of Cr^VI to Cr^III through electrons and protons donated from OH and NH₂ groups of the CS layer; the reduced Cr^III species are adsorbed onto the CS layer via complexation to give chromium-free water.

【 授权许可】

CC BY-NC-ND   
© 2014 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

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