Equilibrium and kinetics of copper ions removal from wastewater by ion exchange

The removal of copper ions from wastewater by ion exchange has been studied using an iminodiacetate resin. The capacity of the resin for the copper ions has been determined to be 2.30 mmol·g^-1 by measuring the equilibrium isotherm at 25 ℃ and initial pH value of 3.5 where the final equilibrium pH value is 5. An analysis of equilibrium isotherm models showed that the best fit model was the Langmuir-Freundlich. The kinetics of the ion exchange process have been investigated and four kinetic models have been tested namely: Ritchie model, pseudo-second order model, pseudo-first order model and the Elovich model. The pseudo-second order model provides the best fit to the kinetic data.