MEMBRANE RECYCLING IN THE LIQUID SURFACTANT MEMBRANE PROCESS

A study has been conducted to investigate the influence of membrane re cycling on the kinetics of metal permeation and emulsion stability in the liquid surfactant membrane process. The analogous stages of the in dustrial process, i.e., emulsification, permeation, settling, and spli tting, have been reproduced, however, so far on a laboratory scale. It has been revealed that after two cycles of the membrane circulation, the kinetics of metals extraction and emulsion stability have been dra stically affected. Chemical and instrumental analysis of the membrane have shown considerable losses in the surfactant (Span 80) during coba lt extraction, while the carrier bis(2-ethylhexyl)phosphoric acid (D2E HPA) has not been affected. This fact has been mainly attributed to th e surfactant chemical instability during exploitation and particularly in acidic media.