A thin film nanocomposite reverse osmosis membrane containing amine-functionalized carbon nanotubes

Thin film composite reverse osmosis (RO) membranes were fabricated by interfacial polymerization of m-phenylenediamine and trimesoyl chloride monomers and modified with amine-functionalized multi-walled carbon nanotubes (MWCNT-NH₂), which dispersed in amine solution. The surface characteristics of the prepared membranes were studied by scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle analysis. The desalination performance of the membranes was investigated in terms of water flux and NaCl rejection. The hydrophilicity and permeability of the modified membranes were increased without any reduction in their salt rejection. The fouling resistance of the membranes was evaluated by their flux decrement through filtration of bovine serum albumin (BSA) solution and water flux recovery ability after the fouling. The incorporating of MWCNT-NH₂ into polyamide layer of RO membranes improved their fouling resistance by reducing surface roughness and increasing negative charge and hydrophilicity of the membrane surface. The membrane containing 0.002 wt% MWCNT-NH₂ presented the best desalination and antifouling performance.