In situ nano-silicate functionalized graphene oxide composites to improve MB removal

In this paper, a novel composite material for methylene blue (MB) removal was successfully synthesized from dolomite and graphene oxide. The graphene oxide/calcium magnesium silicate composite (GO/Si-Ca-Mg) was prepared through in-situ functionalizing silicates on the surface of GO. Briefly, metal ions (Ca2+ or Mg2+) were anchored by oxygen-containing functional groups on the GO and acted as growth centers of silicates. Properties of the material were characterized by XRD, FT-IR, SEM-EDS and TEM, and spectral results implied that silicates were successfully in-situ functionalized on the GO. During the preparation process, experimental factors were studied to investigate the optimum conditions. The adsorption capacity for MB could reach 230 mg/g. Thermodynamic and kinetic studies were also carried out to investigate the adsorption characteristics of the composite. This work came up with a feasible method to synthesize GO/silicate composite, which pleasantly avoided the severe aggregation of silicates in synthesis process. (C) 2017 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.