PROMOTING ACCESS TO AFRICAN RESEARCH

Water SA

Log in or Register to get access to full text downloads.

Remember me or Register



Removal of zinc ions from aqueous solution using micellar- enhanced ultrafiltration at low surfactant concentrations

Z Zhang, GM Zheng, JH Huan, YY Fang, K Xu, YH Qu, CP Yang, JB Li

Abstract


Micellar-enhanced ultrafiltration (MEUF) of zinc ions (Zn2+) from aqueous solutions using single anionic surfactant sodium dodecyl sulphate (SDS) at low critical micelle concentrations (cmc) (0.2×cmc – 3×cmc) was investigated. When the initial SDS concentration was below the cmc, unexpectedly high rejection (97.5%) was obtained due to concentration polarisation occurring near the membrane-solution interface. Based on this mechanism, the true rejection of the solute is no longer a function of the initial SDS concentration in the bulk solution but a function of the SDS concentration at the concentration polarisation layer. The removal of Zn2+ at low Zn2+ feed concentrations was very efficient. The characteristics of Zn2+ ion adsorption to surfactant micelle were also studied. The Langmuir model could be used to elucidate the Zn2+ adsorption isotherm to the SDS micelle. The study demonstrates the potential practicality of the MEUF technique for the removal of heavy metal ion pollutants such as Zn2+ at low surfactant concentrations



http://dx.doi.org/10.4314/wsa.v33i1.48787
AJOL African Journals Online