Adsorptive removal of cetyltrimethyl ammonium bromide (CTAB) surfactant from aqueous solution: Crossbreed pilot plant membrane studies

Magnetic carbon nanocomposite (MCNC) was prepared from peanut shells and then characterized by FTIR, SEM, TGA/DTA and BET surface area. The removal of cetyltrimethyl ammonium bromide (CTAB) surfactant from aqueous solution was carried out by MCNC and membrane. The effect of contact time, initial concentration of CTAB and the temperature on the adsorption of CTAB was also investigated. Initially, the adsorption of CTAB on MCNC was rapid up to 20 min and then gradually slowed down. Different kinetic models i.e. 2^nd pseudo order kinetics, power function and intraparticle diffusion were applied to determine different kinetic parameters. Intraparticle diffusion model showed that the adsorption of CTAB is a diffusion controlled process. Thermodynamic parameters i.e. DH8 (–33.74 kJ/mol), DS8 (0.98 J/mol K) and DG8 (–62.91 kJ/mol, –64.37 kJ/mol and –66.33 kJ/mol) were calculated and the process was found to be exothermic and spontaneous in nature. The prepared adsorbent (MCNC) was used for controlling fouling of ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) membranes caused by CTAB. Improved permeate fluxes and percent retention of CTAB were observed for MCNC crossbreed membrane. About 100% retention with no effect on permeate flux was observed with RO membrane when MCNC pretreatment was applied.