Micellar enhanced ultrafiltration and activated carbon fibre hybrid processes for copper removal from wastewater

Several series of experiments were conducted to investigate copper removal from artificial suspension in micellar enhanced ultrafiltration (MEUF) and activated carbon fibre (ACF) hybrid processes. Sodium dodecyl sulphate (SDS) was used as a surfactant. Copper removal increased with the increase of molar ratio of copper to SDS, operating retentate pressure and initial permeate flux. Permeate flux decreased with the increase of molar ratio of copper to SDS. Specific and relative fluxes declined, respectively, with the increase of retentate pressure and initial permeate flux. Based on removal efficiency and permeate flux, initial permeate flux of 1.05 m(3)/m(2)/day, copper to SDS molar ratio of I : 30 (9.44 mM of SDS), and operating retentate pressure of 1.4 bar were found to be the optimum operating parameters for 0.5 mM or less initial copper concentration. Average copper removal at the optimised condition was 98% and the corresponding permeate copper concentration was less than I mg/L. Adsorptive capacity of activated carbon fibre (ACF) for SDS was 170 mg/g. Langmuir isotherm equation gives a better fit with the experimental results compared to the Freundlich isotherm equation. Overall SDS removal efficiency of two sets of ACF unit in series was 85%.