Utilization of environmentally benign emulsion liquid membrane (ELM) for cadmium extraction from aqueous solution

Abstract

Utilization of Emulsion Liquid Membrane (ELM) for cadmium removal from aqueous solution was explored. Basically, ELM consists of 2 phases; internal and membrane phase that form the primary W/O (water-in-oil) emulsion which to be dispersed in the external phase. In this work, Aliquat 336 and Span 80 were used as carrier and surfactant, respectively whereas corn oil was used as an environmentally benign diluent in the membrane phase. Influence of operating conditions that affect ELM performance; ultrasonic power, emulsification time, treat ratio, stirring speed together with initial cadmium concentration were investigated. It was found that 20W ultrasonic power, 12min emulsification time, treat ratio of 1:5 and 300rpm stirring speed were essential to achieve maximum removal efficiency (98.9%) after 15min. The current study also exhibits the possibility of demulsification process assisted by ultrasonic probe. 48.8% emulsion breaking efficiency was recorded using ultrasonic power≥33W, subjected to 5min of irradiation time.