Copper removal from dilute aqueous solution by emulsion liquid membrane method

Abstract

Copper extraction from dilute aqueous solution by emulsion liquid membrane method was studied. The membrane phase was consisted of LIX 984N as extractant and Span 80 as surfactant in kerosene. Internal aqueous phase was sulfuric acid solution. The effects of parameters such as feed pH, extraction temperature, stirring speed, surfactant concentration, extractant concentration, internal striping phase concentration and feed phase concentration were investigated. The experimental data were presented as plots of the ratio of the instantaneous copper concentration to the initial copper concentration versus time and tabulated as the percentage of copper removal with time. The optimum condition for this study was found to be at feed pH of 5, which was a predominant factor. The process was most efficient at 30°C with stirring speed of 400 rpm, 3 wt% of surfactant, 4 wt% of extractant and 2 M sulfuric acid. More than 99.7% of copper could be removed from the feed phase within 14 minutes when the optimum condition was used. Addition of 1 wt% of ethylene-propylene copolymer as viscosity improver was found to reduce membrane leakage at high speed of agitation. The third reusability of the membrane phase could be achieved with more than 97% copper removal.