Removal of molybdenum (VI) from effluent waste water streams by cross flow micellar enhanced ultrafiltration (MEUF) using anionic, non-ionic and mixed surfactants

Abstract

Micellar Enhanced Ultrafiltration (MEUF) has been used to remove dissolved molybdenum efficiently from the waste streams by using two surfactants: sodium dodecyl sulfate (SDS) and Tween 20 in a lab-scale membrane system. Effect of feed flow rate, time, molar ratio of surfactant to metal (S/M ratio), feed pH and feed molybdenum concentration on %rejection of molybdenum has been studied. Effect of non-ionic (Tween 20) and mixed surfactant (SDS + Tween 20) on %rejection of molybdenum is also studied. Molybdenum is removed by 90.3% at optimized parameters (feed flow rate, time, S/M ratio, pH, feed molybdenum concentration, concentration of SDS) and non-ionic and mixed surfactants removed molybdenum by 92 and 90.4% respectively. Distribution coefficient, loading of micelles and micellar binding constants have been calculated for both the anionic surfactant and mixed surfactant from experimental results. Gel layer formation is found to be negligible since all experiments have been carried out at low range of pollutants.