Removal of Diclofenac, Paracetamol and Metronidazole using a carbon-polymeric membrane

Abstract

In this work, carbon-polymeric membranes were synthesized by an immersion-precipitation method using polysulfone (PSf) as membrane matrix, methylcellulose (MC) as pore forming agent and commercial Powdered Activated Carbon (PAC) as adsorbent additive. All the components were dissolved in N-methylpyrrolidone (NMP) to prepare the casting solutions. The effect of PAC on the structure and the performance of the membranes were studied. The obtained membranes were characterized by water contact angle (CA), Scanning Electron Microscopy (SEM), and mechanical tensile tests. The hydrodynamic characterization of the membranes was studied by the determination of the hydraulic permeability. The efficiency of the carbon-polymeric membranes in the treatment of water was carried out by filtration tests of water containing model molecules of drugs; Diclofenac (DIC), Paracetamol (PARA) and Metronidazole (MET) representing the effluents of the pharmaceutical industry. The results of different analyses showed an improvement in membrane performance by the incorporation of MC and PAC into the membrane matrix. The measurement of the contact angle showed an improvement of the surface hydrophilicity by a decrease in contact angle by about 11° when adding PAC to membrane matrix. SEM analysis showed an asymmetric structure for all membranes, more porous with the presence of more regular finger-like pores compared to the pure PSf membrane. The addition of activated carbon to the membrane matrix increases the Young's modulus to 136.2 MPa and thus increases membrane rigidity. The water permeability of the membranes was enhanced by adding PAC to the membrane matrix, and the removal of pharmaceuticals was considerably increased by 34% and 28% for PARA and MET, respectively.