Surface modification of graphene oxide by pyridine derivatives for copper(II) adsorption from aqueous solutions

Graphene oxide (GO) was covalently modified by series of pyridine derivatives with SOCl2 activation method for adsorption of Cu(II) for the first time. The effects of pyridine derivatives structure, adsorption thermodynamics, kinetics and adsorbents reusability were investigated. The adsorption capacity of modified GO is related to the number of pyridine groups, and substituent position. The maximum adsorption capacity of 4'-carboxy-2,2':6',2 ''-terpyridine modified GO (GO-CTPy) reaches 119.6 mg g(-1), which is much higher than that of other modified GO. The adsorption can be well described by the Langmuir isotherm model and pseudo-second-order kinetic model. GO-CTPy exhibited excellent regeneration and reusability. (C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.