title: Adsorption of Cu(2+), Cd(2+) and Ni(2+) from aqueous single metal solutions on graphene oxide membranes.
abstract: Novel, highly ordered layered graphene oxide (GO) membranes with larger interlayer spacing were prepared by induced directional flow and were used as adsorbents for the removal of Cu(2+), Cd(2+) and Ni(2+) from aqueous solutions. The effects of pH, ionic strength, contact time, metal ion concentration and cycle time on Cu(2+), Cd(2+) and Ni(2+) sorption were investigated. The results indicated that the adsorption of Cu(2+), Cd(2+) and Ni(2+) onto GO membranes was greatly influenced by the pH and weakly affected by the ionic strength. The adsorption isotherms for Cu(2+), Cd(2+) and Ni(2+) were well fitted by the Langmuir model. The maximum adsorption capacities of the GO membranes for Cu(2+), Cd(2+) and Ni(2+) were approximately 72.6, 83.8 and 62.3 mg/g, respectively. The adsorption kinetics of Cu(2+), Cd(2+) and Ni(2+) onto GO membranes followed the pseudo-second-order model. The adsorption equilibrium was reached in a shorter time. The GO membranes can be regenerated more than six times based on their adsorption/desorption cycles, with a slight loss in the adsorption capacity. The results demonstrated that the GO membranes can be used as effective adsorbents for heavy metal removal from water.
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Tan
authors.affiliation: Shcool of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China; State Key Lab of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640, China. Electronic address: ppyyhu@scut.edu.cn.
authors.forename: Yongyou
authors.initials: Y
authors.lastname: Hu
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Fang
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Bi
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China; State Key Lab of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640, China.
authors.forename: Yuancai
authors.initials: Y
authors.lastname: Chen
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China; State Key Lab of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Cheng
keywords: Adsorption; Graphene oxide membrane; Heavy metal ion; Self-assembly