Adsorption of halogenated aliphatic contaminants by graphene nanomaterials. (1st August 2015)

• Record Type: Journal Article
• Authors: Zhou, Yang; Apul, Onur Guven; Karanfil, Tanju
• Is Part Of: Water research. Volume 79(2015)
• Page Start: 57
• Page End: 67
• Publication Date: 2015-08-01
• Subjects: Adsorption -- Aliphatic synthetic organic compounds -- Graphenes -- Carbon nanotubes -- Activated carbons -- Natural organic matter; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2015.04.017
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: In this study, adsorption of ten environmentally halogenated aliphatic synthetic organic compounds (SOCs) by a pristine graphene nanosheet (GNS) and a reduced graphene oxide (rGO) was examined, and their adsorption behaviors were compared with those of a single-walled carbon nanotube (SWCNT) and a granular activated carbon (GAC). In addition, the impacts of background water components (i.e., natural organic matter (NOM), ionic strength (IS) and pH) on the SOC adsorption behavior were investigated. The results indicated HD3000 and SWCNT with higher microporous volumes exhibited higher adsorption capacities for the selected aliphatic SOCs than graphenes, demonstrating microporosity of carbonaceous adsorbents played an important role in the adsorption. Analysis of adsorption isotherms demonstrated that hydrophobic interactions were the dominant contributor to the adsorption of aliphatic SOCs by graphenes. However, π-π electron donor-acceptor and van der Waals interactions are likely the additional mechanisms contributing to the adsorption of aliphatic SOCs on graphenes. Among the three background solution components examined, NOM showed the most influential effect on adsorption of the selected aliphatic SOCs, while pH and ionic strength had a negligible effects. The NOM competition on aliphatic adsorption was less pronounced on graphenes than SWCNT. Overall, in terms of adsorption capacities, graphenes tested in this study did not exhibit a major advantage over SWCNT and GAC for the adsorption of aliphatic SOCs. Graphical abstract: Highlights: Graphene nanomaterials adsorb halogenated aliphatic SOCs. The effect of NOM was smaller on adsorption capacity of graphenes than CNTs. rGO showed comparable adsorption capacities in NOM solution and DDW. Hydrophobicity was the dominant factor in the adsorption of tested aliphatic SOCs by graphenes. CNTs and GAC exhibited higher adsorption capacities for aliphatic SOCs than graphenes.