Removal of Pb and Cu ions from aqueous solution by Mn3O4-coated activated carbon

Abstract

Mn3O4-coated activated carbon (Mn3O4/AC) was prepared by supercritical technique and applied for the removal of Pb and Cu ions from aqueous solution. Kinetic and isotherm data of the adsorption by Mn3O4/AC were compared with those of activated carbon (AC) and pure Mn3O4. Adsorption of metals was adequately described by pseudo-second-order kinetics and Langmuir isotherm models. Maximum adsorption capacities of Pb and Cu ions determined by Langmuir model were enhanced 2.2 and 6.1 times for Pb and Cu ions by Mn3O4 coating onto AC, which might be attributed to reduced resistance of intraparticle diffusion and enhanced surface electrostatic interaction and complexation by Mn3O4. (C) 2014 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.