Preparation of graphene oxide membranes by vacuum self-assembly for copper separation in water

Abstract A composite membrane of Graphene oxide (GO) with polyethylene glycol (PEG) as a cross-linking agent was prepared by the vacuum self-assembly method and investigated for its ion selectivity and separation performance towards Cu2+. PEG also served as a pore-forming agent to improve water flux and stability of GO membranes in an aqueous solution. The effects of PEG ratio, solution concentration, and pH on membrane permeation performance were studied. The water flux of PEG:GO = 1:5 composite membrane was 9.4 L m−2 h−1 bar−1, and the selection factor of Cu2+/Fe3+ reached 4.41, indicating good ion selectivity. The separation experiment of copper ions in aspirin showed considerable separation performance of the as-prepared membrane in removing Cu2+.