Huijuan Zhang,Bin Li,Jiefeng Pan,Yawei Qi,Jiangnan Shen,Congjie Gao,Bart Van der Bruggen
Novel carboxyl-functionalized graphene oxide (CFGO)/polyamide (PA) nanofiltration (NF) membranes were prepared via interfacial polymerization (IP) of piperazine (PIP) and trimesoyl chloride (TMC). CFGO was fabricated by a chemical modification (ring opening followed by esterification) to the epoxide ring of GO. CFGO was then introduced in the PIP aqueous phase as an additive in the IP reaction. Compared with a pristine PA reference membrane, both the GO/PA and CFGO/PA membrane have an enhanced permeability (the optimum concentration of GO and CFGO in the membrane was 0.05% and 0.07%, and the corresponding water flux is 96.5 and 112.1 L/m 2 /h, respectively),with a slight decrease of the salt rejection. In dye desalination experiment, the permeation flux of 0.05%GO/PA membrane is only 75.5 L/m 2 /h, with 98.1% rejection of New Coccine (a dye with negative charge) and 28.7% retention for NaCl. For 0.07%CFGO/PA membrane, it can cut off 25.0% NaCl and 95.1% New Coccine, and its permeation flux can reach 110.4 L/m 2 /h, which shows that the CFGO/PA membrane could be potentially applied to the dye desalination and concentration process . The CFGO/PA membrane shows better performances in permeability and dye desalination than GO/PA membrane, due to the significantly increased hydrophilicity and enhanced surface charge density.
Mei-Ling Liu,Lu Li,Yu-Xuan Sun,Zheng-Jun Fu,Xue-Li Cao,Shi-Peng Sun
Efficient water treatment by a membrane with enduring high permeability and rejection is still a challenge because of the commonly recognized trade-off effect and the pore-blocking induced fouling issue. Herein, the scalable production of electro-conductive polyaniline/polyimide membranes for electrocatalysis enhanced filtration is reported for the first time. The prepared membrane presents the following significant advantages: (1) superior dye-solution permeability (204.1 L m −2 h −1 bar −1 ) while not sacrificing selectivity (99.8% for congo red), which is benefited from the synergic interplay of the enhanced hydrophilicity, enlarged pore size and high adsorption active site; (2) elevated electrical conductivity by almost two orders of magnitude, leading to significantly improved permeability recovery rate (87%) and electro-oxidative pollutant removal; (3) optimal compatibility of the two polymers results in robust mechanical strength without micro-cracks, which realizes large-scale membrane fabrication without performance deterioration. These results indicate that the synergy of electrocatalytic polymers with robust filtration polymers through direct phase inversion strategy will provide a paradigm shift of designing high-performance membranes with practical applications.
危险品化学品经营许可证（带存储）