Preparation and Characterization of Chitosan Thin Films on Mixed‐Matrix Membranes for Complete Removal of Chromium. Issue 3 (12th February 2015)

• Record Type: Journal Article
• Authors: Nayak, Vignesh; Jyothi, Mannekote Shivanna; Balakrishna, R. Geetha; Padaki, Mahesh; Ismail, Ahmad Fauzi
• Is Part Of: ChemistryOpen. Volume 4:Issue 3(2015:Jun.)
• Page Start: 278
• Page End: 287
• Publication Date: 2015-02-12
• Subjects: Chemistry -- Periodicals; 540; 540.5
• DOI: 10.1002/open.201402133
• Languages: English
• ISSNs: 2191-1363

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>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 &lt; PSf/TiO₂ &lt; 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.</p> </abstract>