Effects of operating parameters on efficiency of lead removal by complexation-microfiltration process

Abstract

Majority of lead content found in the environment is the result of human activities. Heavy metals can be hazardous because they tend to bioaccumulate. Complexation-microfiltration process for the removal of Pb(II) ions was studied. The aim of microfiltration of the model wastewater containing heavy metal ions was finding an optimum ratio between the concentrations of the complexing agent and metal, and determining the most favorable pH value. The microfiltration experiments were carried out in a stirred dead-end cell. Diethylaminoethyl cellulose (DEAE 23) was selected as the complexing agent. Versapor membranes were used to separate formed polymer-metal complex. The concentration of heavy metal ions after microfiltration in aqueous solution was determined using the atomic absorption spectroscopy (AAS). Effects on the amount of complexing agent, concentration of metal ion, pH value and operating pressure on the flux, J, and rejection coefficient, R, were investigated. Experimental results indicate that the pH of the solution has considerable influence on the rejection coefficient. An increase in pH and the amount of complexing agents enabled us to obtain very high retention coefficient (99%).