Removal of copper from a simulated wastewater by electromembrane extraction technique using a novel electrolytic cell provided with a flat polypropylene membrane infused with 1-octanol and DEHP as a carrier

Abstract

The objective of this study was to implement an electromembrane extraction (EME) system to eliminate copper from aqueous solutions. A unique design of an electrochemical cell was used. It consists of two glass chambers, a supported liquid membrane (SLM), graphite anode, and stainless-steel cathode. SLM was composed from polypropylene flat membrane infused with 1-octanol and a carrier. Two different carriers, namely tris(2-ethylhexyl) phosphate (TEHP) and bis(2-ethylhexyl) phosphate (DEHP), were evaluated. Effect of several factors, including the type of carrier, applied voltage, initial pH of the donor solution, and initial copper concentration, on the efficiency of copper removal was investigated thoroughly. The outcomes revealed the significant role played by the applied voltage in augmenting the rate of mass transfer of copper across the membrane. Through meticulous optimization, we determined the optimal operating conditions for the EME process, which involved utilizing 1-octanol containing 1.0% v/v bis(2-ethylhexyl) phosphate as the carrier, applying a voltage of 60 V, an initial pH of 5, utilizing an initial copper concentration of 15 mg/L, conducting the extraction for 6 hours, and maintaining a stirring rate of 1000 rpm. Notably, under these optimized conditions, an impressive removal efficiency of 88% was achieved. Furthermore, a comparison with the case of no applied voltage application demonstrated a substantial increase in the efficiency of copper removal, rising from 33% to 88% at an applied voltage of 60 V. This observation emphasizes the potential effectiveness of the EME technique in effectively eliminating heavy metals, such as copper, from aqueous solutions.

Keywords

• Copper removal
• Electromembrane extraction
• Organic solvent
• Carrier molecule
• Wastewaters