Application of Nanofiltration Membrane in the Separation of Amoxicillin from Pharmaceutical Wastewater

Separation of amoxicillin from pharmaceutical wastewater by nanofiltration (NF) membrane has been investigated in this study. For this purpose a membrane system including a polyamide spiral wound NF membrane was evaluated for the treatment of amoxicillin wastewater. The effects of operating conditions such as flow rate, pressure and concentration of amoxicillin and COD in the feed, on the efficiency of the membrane were evaluated. The permeation flux and rejection of amoxicillin and COD were the criteria for this evaluation. The rejection of the amoxicillin by the selected NF membrane was adequate and in most cases exceeded 97% whereas COD reached a maximum of 40% rejection and permeation flux was over 1.5 L/min.m2. The rise in pressure enhanced the transport rate of the solvents. Permeation flux of the NF membrane increased with increasing flow rates. Experimental data also indicated that concentration polarization existed in this membrane separation process. The stable permeation flux and high rejection of amoxicillin indicated the potential of NF for the recovery of amoxicillin from the pharmaceutical wastewater.