Optimization of process conditions for the removal of zinc and lead by ultrafiltration using biopolymer

Abstract

Water pollution by the discharge of industrial effluents containing heavy metal contaminants has become a worldwide environmental problem. The major pollutants present in industrial effluents are Cu(II), Ni(II), Zn(II), Pb(II), and Cr(VI). To protect the environment from the harmful effects of these heavy metals, we need a proficient technology. The size-enhanced ultrafiltration (SEUF) is a competent technique for the removal and recovery of heavy metal contaminants from the effluent. This paper deals with the removal of Zn(II) and Pb(II) by size-enhanced ultrafiltration with biopolymer carboxymethyl chitosan (CMCh). The design of experiments was performed by response surface methodology (RSM). The significance of the process parameters and the predicted model equations have been validated through analysis of variance (ANOVA). The effects of process conditions such as pH of feed solution, loading rate, and concentration of metal ions on percentage retention and binding capacity of CMCh have been investigated. The optimized process parameters have been compared with the experimental findings. The results depict the success of the process in the removal and recovery of Zn(II) and Pb(II) by SEUF using carboxymethyl chitosan. The characteristics of CMCh complexation with metal ions have been analyzed through SEM and EDAX and FTIR.