Nanofiltration membranes to reduce phenol concentration in wastewater

Physical, chemical and biological methods have been described to remove phenolic compounds. None of them are the definitively solution of the environmental problem caused by the discharge of this pollutants. Hybrid processes that combine pressure driven membrane processes with adsorption processes have been developed. Our research group studied the removal of phenol with three reverse osmosis membranes, the rejection percentages obtained were very low (40%), besides this parameter increases when the operating pressure decreases. For this reason, in this paper, a study of phenol removal from aqueous solutions by nanofiltration using different experimental conditions (feed phenol concentration, pressure and pH) and different membranes (NF-97, NF-99 and DSS-HR98PP) is carried out. Water permeability coefficients were also obtained. The best results are obtained with DSS-HR98PP membrane increasing the rejection percentage up to 80%.