Bioinspired synthesis of multi-walled carbon nanotubes based enoxacin-imprinted nanocomposite membranes with excellent antifouling and selective separation properties

Abstract

Abstract Inspired from the bioadhesive surface modified technology of polydopamine (pDA) and the radical polymerization method of amphiphilic grafted copolymer (ACMO@PVDF), the bioinspired porous enoxacin-imprinted nanocomposite membranes (EINCMs) were synthesized by developing the multi-walled carbon nanotubes (MCNTs)-based nanocomposite structure. The EINCMs were prepared through immersion phase inversion method and sol–gel blot imprinted method for selective purification and separation of enoxacin. Testing results indicated that the surface physicochemical properties such as higher micropores, significantly improved hydrophilicity and enhanced antifouling ability, could be successfully obtained. Results showed that the specific adsorption capacity was markedly enhanced from 3.72 mg g−1, which was for the non-imprinted nanocomposite membrane (NINCMs), to 31.56 mg g−1 for the imprinted one. In addition, the imprinting factor β was proved as high as 4.44 and the perm-selectivity of membrane was also measured in the form of separation factor γ, which was calculated as 6.03. Furthermore, the rebinding capacities reached about over 90. 36% of the initial adsorption capacity after 5 cycles of adsorption/desorption. The rebinding capacity just only declined to 82.89% after another 5 cycles rebinding circulations. The highly stable stability and homogeneous growth of enoxacin-imprinted layers on pDA@MCNTs surfaces might probably be the reason for desirable performance and stability. The as-obtained results could be concluded that this synthesis method would provide wastewater treatments containing enoxacin with a highly stable and selective separation performance.