Chemical Engineering Journal, Vol.293, 44-54, 2016
Microchannel-embedded metal-carbon-polymer nanocomposite as a novel support for chitosan for efficient removal of hexavalent chromium from water under dynamic conditions
A blend of micron-sized chitosan and carbon nanofibers (CNFs)-supported iron (Fe)-oxide nanoparticles (NPs) was dispersed in a modified polyvinyl alcohol to produce an approximately 1 mm-thick metal-car bon-polymer nanocomposite film. The film was laser-ablated to create microchannels (150 mu m-wide, 100 mu m-deep and 30 mm-long), thereby exposing the in situ dispersed chitosan and Fe-oxide NPs to the surrounding liquid through the porous walls of the fabricated microchannels. The prepared micro textured nanocomposite film was used as a novel contactor for the remediation of hexavalent chromium (Cr(VI))-contaminated water under flow conditions. The material showed a high metal-uptake (similar to 80 mg per g of chitosan/Fe-CNF composite), which was approximately the same as the equilibrium adsorption capacity determined under batch conditions. The spent nanocomposite film could be successfully regenerated and reused four times. The prepared material cum contactor in this study provides a potential solution to the difficulty of supporting all such micron- and submicron (nano)-sized metal/polymer particles that are prone to elution in liquid flow, by providing them a mechanically and thermally stable support for their practical use in separation and purification applications. (C) 2016 Elsevier B.V. All rights reserved.