Most suitable amino silane molecules for surface functionalization of graphene oxide toward hexavalent chromium adsorption. (July 2020)

• Record Type: Journal Article
• Authors: Lee, JinHyeong; Park, Jeong-Ann; Kim, Hee-Gon; Lee, Jung-Hyun; Cho, So-Hye; Choi, Keunsu; Jung, Kyung-Won; Lee, Seung Yong; Choi, Jae-Woo
• Is Part Of: Chemosphere. Volume 251(2020)
• Publication Date: 2020-07
• Subjects: Graphene oxide -- Amino silane -- Functionalization -- Hexavalent chromium -- Adsorption; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2020.126387
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Adsorption is a simple and effective method for the removal of hexavalent chromium (Cr(VI)) from contaminated water. Several amino silane–graphene oxide (GO) composites with different species of amino groups (pN-GO, psN-GO, and pssN-GO; p: primary, s: secondary, N: amine) were evaluated to investigate their adsorption capacity and the effects of primary and secondary amines on Cr(VI) adsorption. We conducted a quantitative analysis to reveal the difference between primary and secondary amines in terms of Cr(VI) removal efficiency. A synergic effect was observed between the neighboring secondary amines in pssN-GO. From the Langmuir model prediction, we found that the composite with pssN-GO exhibited the highest maximum adsorption capacity (260.74 mg/g), followed by those with psN-GO (208.22 mg/g) and pN-GO (189.47 mg/g). Monolayer adsorption was more dominant when using pssN-GO, with the pseudo-second-order model best fitting the kinetic experiment results, whereas multilayer adsorption was dominant when using psN-GO and pN-GO. Graphical abstract: Image 1 Highlights: Amine–graphene oxide composites with different amino silane groups were prepared. Monolayer adsorption was dominant in pssN-GO, while multilayer on in the others. pssN-GO with Cr(VI) removal capacity of 260.74 mg/g was superior to the others. Protonation of secondary amine was less affected by pH than that of primary amine.