Removal of Lead from Wastewater Using Emulsion Liquid Membrane Technique

Abstract

A detailed study was conducted to remove lead from storage battery industry wastewater by using emulsion liquid membrane (ELM) technique. The storage battery industry wastewater has an initial lead concentration of 4.2 ppm (average) and a pH value of 1.4. Emulsion liquid membrane consisted of kerosene and mineral oil as organic solvents, sorbitan monooleate (Span 80) as a surfactant, di-2-ethylhexyl phosphoric acid (D2EHPA) as a carrier or extractant, and sulphuric acid (H<inf>2</inf>SO<inf>4</inf>) as a stripping agent. The important variables affecting the ELM systems, such as organic solvents, surfactant, and carrier concentrations, internal stripping phase normality, external aqueous phase pH value, and normality of organic ligand added, have been investigated systematically. The system which adjusted to a pH value of 4.0, obtained the maximum lead removal in first 5 min of the treatment studies and exhibited a low turbidity and swelling at the end of the experiment. © Mary Ann Liebert, Inc.