TY - JOUR
T1 - Effect of varying piperazine concentration and post-modification on prepared nanofiltration membranes in selectively rejecting organic micropollutants and salts
AU - Liu, Yan ling
AU - Zhao, Yang ying
AU - Wang, Xiao mao
AU - Wen, Xiang hua
AU - Huang, Xia
AU - Xie, Yuefeng F.
N1 - Funding Information:
We acknowledge the funding for this research provided by the National Natural Science Foundation of China (No. 51761125013 and No. 51678331 ) and the special fund of State Key Joint Laboratory of Environment Simulation and Pollution Control ( 18Y01ESPCT ), Tsinghua University .
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/7/15
Y1 - 2019/7/15
N2 - Nanofiltration (NF) is considered as a promising technology for the removal of trace organic compounds (TrOCs) for wastewater reclamation, while a simultaneous low rejection of salts is desirable for the ease of using the reclaimed water. This study was conducted to exploit the potential of polypiperazine-amide NF membranes in achieving selective separation of TrOCs and NaCl by varying the concentration of the diamine monomer, piperazine (PIP), for interfacial polymerization and by modifying the nascent membrane surface with hydrophilic monomers, diethanolamine (DEA) and monoethanolamine (MEA). Results showed that increasing PIP concentration could decrease the membrane pore size and reduce the surface negative charge density, which led to an increased rejection of xylose and a reduced rejection of NaCl. The grafting of DEA or MEA molecules could further decrease the NaCl rejection, substantially improve the water permeability and maintain an effective removal for eight pharmaceuticals (PhACs). The optimal membrane prepared with a PIP concentration of 2.0 wt% and subsequently modified by MEA exhibited a rejection of NaCl at 33.1% and an average rejection of PhACs at 90.8% in a 10 mmol/L NaCl solution under an applied pressure of 6 bar. The membrane could have an even higher selectivity when the NaCl concentration was increased to higher levels. These results demonstrated the feasibility and versatility of the membrane in separating TrOCs from NaCl for wastewater reclamation.
AB - Nanofiltration (NF) is considered as a promising technology for the removal of trace organic compounds (TrOCs) for wastewater reclamation, while a simultaneous low rejection of salts is desirable for the ease of using the reclaimed water. This study was conducted to exploit the potential of polypiperazine-amide NF membranes in achieving selective separation of TrOCs and NaCl by varying the concentration of the diamine monomer, piperazine (PIP), for interfacial polymerization and by modifying the nascent membrane surface with hydrophilic monomers, diethanolamine (DEA) and monoethanolamine (MEA). Results showed that increasing PIP concentration could decrease the membrane pore size and reduce the surface negative charge density, which led to an increased rejection of xylose and a reduced rejection of NaCl. The grafting of DEA or MEA molecules could further decrease the NaCl rejection, substantially improve the water permeability and maintain an effective removal for eight pharmaceuticals (PhACs). The optimal membrane prepared with a PIP concentration of 2.0 wt% and subsequently modified by MEA exhibited a rejection of NaCl at 33.1% and an average rejection of PhACs at 90.8% in a 10 mmol/L NaCl solution under an applied pressure of 6 bar. The membrane could have an even higher selectivity when the NaCl concentration was increased to higher levels. These results demonstrated the feasibility and versatility of the membrane in separating TrOCs from NaCl for wastewater reclamation.
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U2 - 10.1016/j.memsci.2019.04.018
DO - 10.1016/j.memsci.2019.04.018
M3 - Article
AN - SCOPUS:85064451860
VL - 582
SP - 274
EP - 283
JO - Journal of Membrane Science
JF - Journal of Membrane Science
SN - 0376-7388
ER -