Removal of Copper, Nickel, and Zinc Ions from an Aqueous Solution through Electrochemical and Nanofiltration Membrane Processes

Jagdeesh Kumar,Himanshu Joshi,Sandeep K Malyan

doi:10.3390/app12010280

Abstract

Heavy metal contamination in water is a major health concern, directly related to rapid growth in industrialization, urbanization, and modernization in agriculture. Keeping this in view, the present study has attempted to develop models for the process optimization of nanofiltration (NF) membrane and electrocoagulation (EC) processes for the removal of copper, nickel, and zinc from an aqueous solution, employing the response surface methodology (RSM). The variable factors were feed concentration, temperature, pH, and pressure for the NF membrane process; and time, solution pH, feed concentration, and current for the EC process, respectively. The central composite design (CCD), the most commonly used fractional factorial design, was employed to plan the experiments. RSM models were statistically analyzed using analysis of variance (ANOVA). For the NF membrane, the rejection of Zn, Ni, and Cu was observed as 98.64%, 90.54%, and 99.79% respectively; while the removal of these through the EC process was observed as 99.81%, 99.99%, and 99.98%, respectively. The above findings and a comparison with the conventional precipitation and adsorption processes apparently indicate an advantage in employing the NF and EC processes. Further, between the two, the EC process emerged as more efficient than the NF process for the removal of the studied metals.

Highlights

IntroductionHeavy metals are inorganic elements naturally found throughout the earth’s crust [1]
Heavy metals are inorganic elements naturally found throughout the earth’s crust [1].Their concentration above permissible limits is considered pollution
The primary emphasis of the present study is to explore the efficiency of removal of Cu, Ni, and Zn by NF and EC processes from their synthetic aqueous solutions in low to high concentrations

Summary

Introduction

Heavy metals are inorganic elements naturally found throughout the earth’s crust [1]. Their concentration above permissible limits is considered pollution. Industrial discharges, agricultural runoff, storm water, mining activity, and direct inclusion of sewage/wastewater contribute to the heavy metal pollution load in fresh water, leading to various health and environmental problems. Among the commonly reported heavy metals, copper (Cu) is used widely in electroplating, batteries, pesticides, galvanized pipes, and alloys [3,4,5,6,7]. Nickel (Ni) is another metal found widely in water and wastewater. The electroplating industry, rechargeable batteries, and galvanized pipes are its main sources. High levels of nickel contamination cause serious lung and kidney problems as well as skin dermatitis and pulmonary fibrosis

Methods

Results

Conclusion