Extraction of copper from wastewater through supported liquid membrane using tri-ethanolamine as a carrier

Abstract

In the present work, the extraction of copper(II) ions through a tri-ethanolamine/cyclohexanone-based supported liquid membrane (SLM), has been investigated. The polypropylene (Celgard 2400) was used as a membrane. The various experimental parameters at room temperature including feed pH, feed, carrier, and strip phase concentration were optimized to acquire the optimum conditions for the extraction of copper(II) ions from waste water. Oxalic acid, sodium carbonate, sodium sulfate, nitric acid, and ethylene-di-amine-tetra-acetate (EDTA) were tested for best stripping reagent for SLM configuration. The extraction time, flux value, stoichiometry of the complex formed, and membrane stability was also investigated. The optimum experimental conditions for copper(II) extraction were 3.5 mol/L tri-ethanol amine (TEA) in the membrane phase as carrier, 1 mol/L hydrochloric acid and 3.17 × 10⁻³ mol/L copper(II) in the feed, and 0.03 mol/L EDTA in the strip solutions. Under these optimum conditions, the extraction time was found to be 120 min and membrane was stable for about 10 consecutive experiments. The transport efficiency of copper(II) ions was found to be 87% under the optimized conditions.

Keywords:

• Supported liquid membrane
• Tri-ethanolamine
• Copper(II)
• Stripping reagent
• Transport efficiency

Acknowledgment

The authors are greatly thankful to the Higher Education Commission (HEC) of Pakistan for providing funding for this project and PhD scholarship to one of the authors (Robila Nawaz).