To advance commercial application of forward osmosis (FO), we investigated the effects of two additives on the performance of polysulfone (PSf) based FO membranes: one is poly(ethylene glycol) (PEG), and anot...To advance commercial application of forward osmosis (FO), we investigated the effects of two additives on the performance of polysulfone (PSf) based FO membranes: one is poly(ethylene glycol) (PEG), and another is PSf grafted with PEG methyl ether methacrylate (PSf-g-PEGMA). PSf blended with PEG or PSf-g- PEGMA was used to form a substrate layer, and then polyamide was formed on a support layer by interfacial polymerization. In this study, NaC1 (1 mol·L^-1) and deionized water were used as the draw solution and the feed solution, respectively. With the increase of PEG content from 0 to 15 wt-%, FO water flux declined by 23.4% to 59.3% compared to a PSf TFC FO membrane. With the increase of PSf-g-PEGMA from 0 to 15 wt-%, the membrane flux showed almost no change at first and then declined by about 52.0% and 50.4%. The PSfwith 5 wt-% PSf-g-PEGMA FO membrane showed a higher pure water flux of 8.74 L·m^-2·h^-1 than the commercial HTI membranes (6-8 L·m^-2·h^-1) under the FO mode. Our study suggests that hydrophobic interface is very important for the formation ofpolyamide, and a small amount of PSf- g-PEGMA can maintain a good condition for the formation of polyamide and reduce internal concentration polarization.展开更多
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (Grant No. 51278317). We would like to express our special thanks to Prof. Elimelech and his group members at Yale University (New Haven, CN, USA) for guidance on FO experimental setups and interfacial polymerization.
文摘To advance commercial application of forward osmosis (FO), we investigated the effects of two additives on the performance of polysulfone (PSf) based FO membranes: one is poly(ethylene glycol) (PEG), and another is PSf grafted with PEG methyl ether methacrylate (PSf-g-PEGMA). PSf blended with PEG or PSf-g- PEGMA was used to form a substrate layer, and then polyamide was formed on a support layer by interfacial polymerization. In this study, NaC1 (1 mol·L^-1) and deionized water were used as the draw solution and the feed solution, respectively. With the increase of PEG content from 0 to 15 wt-%, FO water flux declined by 23.4% to 59.3% compared to a PSf TFC FO membrane. With the increase of PSf-g-PEGMA from 0 to 15 wt-%, the membrane flux showed almost no change at first and then declined by about 52.0% and 50.4%. The PSfwith 5 wt-% PSf-g-PEGMA FO membrane showed a higher pure water flux of 8.74 L·m^-2·h^-1 than the commercial HTI membranes (6-8 L·m^-2·h^-1) under the FO mode. Our study suggests that hydrophobic interface is very important for the formation ofpolyamide, and a small amount of PSf- g-PEGMA can maintain a good condition for the formation of polyamide and reduce internal concentration polarization.