Chemical Engineering Journal, Vol.308, 1001-1009, 2017
Hydroxyl-containing organic molecule induced self-assembly of porous graphene monoliths with high structural stability and recycle performance for heavy metal removal
Three-dimensional (3D) graphene-based architectures are one new type of adsorption materials for environmental purification. Here, we report a facile approach to fabricate 3D graphene oxide (GO) monoliths based on the auxiliary cross-linkage of simple organic molecules with double hydroxyls/carboxyls. Hydroxyl-containing molecules are more conducive than carboxyl-containing agents to induce GO macrostructures with well structural stability and plasticity. The GO-based monoliths cross-linked by hydroxyl-containing agents, especially glycol with double hydroxyls, show a high removal capacity for Pb2+, which also exhibit excellent recyclability via easy regeneration. Quantitative analysis reveals that the organic molecules with hydroxyl groups generate more dissociable groups in the 3D monolith, which provide more active sites for Pb2+ binding. Thus GO-based monoliths derived from the cross-linkage of hydroxyl-containing agents have a great potential for heavy metal removal. (C) 2016 Elsevier B.V. All rights reserved.