Kinetic study of the removal of Cu(II) from aqueous solutions by rolling mill scale

The removal of Cu(II) from aqueous solutions by rolling mil scale occurs through a process of oxidation-reduction or cementation of Cu''2+ ions in aqueous solution onto metallic iron (Fe''0) contained in the mill scale. The kinetics of cementation of copper onto iron was evaluated over different temperatures, initial copper concentrations and solid/liquid relations. Process of copper removal by rolling mill scale obeys a first-order kinetic law. The rate constant value (k) varies with temperature and initial cation concentration in solution at low temperatures. At high temperatures the value of k remains practically constant. the solid/liquid relation value affects the rate constant value too. (Author) 19 refs