High dye separation performance of novel Cu-BTC/PES MMMs with water-stabilized Cu-BTC nanoparticles

Metal-organic frameworks (MOFs), as porous materials, have been extensively applied in a variety of realms, but little of these has been reported used in sewage disposal field owing to its precariousness toward water. Herein, a novel mixed matrix membrane of polyethersulfone (PES) was synthesized using Cu-BTC-IPA, a hydrolytic resistance MOF modified with isopropanol (IPA), which exhibits high permeability and water stability. A significant increase in hydrophilicity of the membrane was found in the modified membranes compared with the pure membrane. The porosity measurement confirmed the increased efficiency of mass transfer in the modified membranes. An enhancement in membrane performance was observed by introducing the Cu-BTC-IPA filler into the PES matrix, with a remarkable increase (207%) in pure water flux observed compared to that of the pristine PES membrane (264.2 L m(-2) h(-1) bar(-1)), reaching 546.4 L m(-2) h(-1) bar(-1). Meanwhile, it exhibited superior rejection of dyestuffs (98.4% for Congo red and 98.9% for Coomassie brilliant blue). In addition, the Cu-BTC-IPA/PES mixed matrix membrane demonstrated remarkable anti-biofouling properties, as evidenced by its high flux recovery rates of bovine serum albumin (BSA) solutions. The consequences indicate that introducing stable MOF into mixed matrix membranes (MMMs) is extremely effective in improving membrane performance for sewage treatment.