Application of micellar enhanced ultrafiltration and activated carbon fiber hybrid processes for lead removal from an aqueous solution

Micellar enhanced ultrafiltration (MEUF) and activated carbon fiber (ACF) hybrid processes were used to investigate the removal condition of lead ions and surfactant sodium dodecyl sulfate (SDS) from an aqueous solution. Lead removal efficiency increased with the increase of initial surfactant concentration. Molar ratio of lead to SDS up to 1 : 5 has shown over 90% removal efficiency of lead, and the optimum molar ratio of lead to SDS was found to be 1: 5. Lead removal efficiency increased with the increase of pH, while it was maintained below 30% without surfactant. Lead removal was mainly due to the adsorption mechanism and no secondary layer was formed to reduce the flux. Lower molecular weight cut-off (MWCO) membrane has shown higher removal efficiency than higher MWCO one. Permeate flux decreased with the increase of molar ratio of lead to SDS. Flux decline was mainly due to the accumulation of micelles on the membrane surface. The presence of copper as a co-existing heavy metal highly affected the lead removal while nickel did not. Two sets of ACF unit in series were able to remove SDS surfactant effectively from the effluents of MEUF process.