Reduced graphene oxide–metal nanoparticle composite membranes for environmental separation and chloro-organic remediation. Issue 66 (26th November 2019)

• Record Type: Journal Article
• Authors: Aher, Ashish; Thompson, Samuel; Nickerson, Trisha; Ormsbee, Lindell; Bhattacharyya, Dibakar
• Is Part Of: RSC advances. Volume 9:Issue 66(2019)
• Page Start: 38547
• Page End: 38557
• Publication Date: 2019-11-26
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c9ra08178j
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : This study explores the integration of separation performance was achieved in a loose nanofiltration regime with heterogeneous oxidation reactions for remediation of organic contaminants from water. Abstract : This study explores the integration of separation performance of rGO membrane with heterogeneous oxidation reactions for remediation of organic contaminants from water. Herein, an approach was introduced based on layer-by-layer assembly for functionalizing rGO membranes with polyacrylic acid and then by in situ synthesis of Fe based reactive nanoparticles. TEM characterization of the cross-section lamella of the membranes showed a high density of nanoparticles (12% Fe) in the functionalized domain, signifying the importance of polyacrylic acid for in situ synthesis of nanoparticles. The membranes exhibited a pure water permeability of 1.9 LMH bar −1 . The membranes had low to moderate salt retention, and more than 90% neutral red retention (organic probe molecule, size: 1.2 nm). The membranes also exhibited high retention of humic acids (80%), preventing these organics from entering the reactive domain, and thus potentially reducing the formation of undesired by-products. A persulfate mediated oxidative pathway was employed to demonstrate the reactive removal of organic contaminants. The membranes achieved >95% conversion by convectively passing 2 mM persulfate feed at a transmembrane pressure of 0.4 bar. Successful degradation of TCE (up to 61%) was achieved in a single pass by convective flowing of the feed solution through the membrane, generating up to 80% of the theoretical maximum chloride as one of the byproducts. Elevated temperatures significantly enhanced persulfate mediated TCE oxidation extent from 24% at 23 °C to 54% at 40 °C under batch operating conditions.