In this paper, a polyethersulfone (PES)/multi-walled carbon nanotubes (MWCNTs) composite membrane was prepared us- ing phase inversion. The surface morphology and internal structure of the membrane were observed b...In this paper, a polyethersulfone (PES)/multi-walled carbon nanotubes (MWCNTs) composite membrane was prepared us- ing phase inversion. The surface morphology and internal structure of the membrane were observed by scanning electron microscopy (SEM). The effects of MWCNTs content on various aspects of membrane performance such as porosity, water flux, and antifouling characteristics were investigated. Results showed that proper addition of MWCNTs would improve the properties of the membrane. MWCNTs had a strong adsorption capacity for industrial dyes and the composite membrane could be used as an effective method to identify and clean up illegal dyes in foods. In addition, this new method for iden- tifying dyes is rapid: the cleanup procedure in the determination of illegal dyes in foods by the composite membrane was shortened to 30 min or less compared to 6-8 h for traditional methods.展开更多
As a routine measurement to alleviate membrane fouling, hydraulic cleaning is of great significance for the steady operation of ultrafiltration(UF) systems in water treatment processes. In this work, a comparative s...As a routine measurement to alleviate membrane fouling, hydraulic cleaning is of great significance for the steady operation of ultrafiltration(UF) systems in water treatment processes. In this work, a comparative study was performed to investigate the effects of the composition of backwash water on the hydraulic cleaning performance of UF membranes fouled by humic acid(HA). Various types of backwash water, including UF permeate, Milli-Q water, Na Cl solution, CaCl_2 solution and HA solution, were compared in terms of hydraulically irreversible fouling index, total surface tension and residual HA. The results indicated that Milli-Q water backwash was superior to UF permeate backwash in cleaning HA-fouled membranes, and the backwash water containing Na+or HA outperformed Milli-Q water in alleviating HA fouling. On the contrary, the presence of Ca^(2+) in backwash water significantly decreased the backwash efficiency. Moreover, Ca^(2+) played an important role in foulant removal, and the residual HA content closely related to the residual Ca^(2+) content.Mechanism analysis suggested that the backwash process may involve fouling layer swelling, ion exchange, electric double layer release and competitive complexation. Ion exchange and competitive complexation played significant roles in the efficient hydraulic cleaning associated with Na+and HA, respectively.展开更多
基金supported by the Fund of Key Projects of Higher Education in Henan Province, China (17A550018)the Fund of Henan Province Science and Technology Research Project, China (172102310314)
文摘In this paper, a polyethersulfone (PES)/multi-walled carbon nanotubes (MWCNTs) composite membrane was prepared us- ing phase inversion. The surface morphology and internal structure of the membrane were observed by scanning electron microscopy (SEM). The effects of MWCNTs content on various aspects of membrane performance such as porosity, water flux, and antifouling characteristics were investigated. Results showed that proper addition of MWCNTs would improve the properties of the membrane. MWCNTs had a strong adsorption capacity for industrial dyes and the composite membrane could be used as an effective method to identify and clean up illegal dyes in foods. In addition, this new method for iden- tifying dyes is rapid: the cleanup procedure in the determination of illegal dyes in foods by the composite membrane was shortened to 30 min or less compared to 6-8 h for traditional methods.
基金supported by the National Natural Science Foundation of China (No. 51308146)the Program for New Century Excellent Talents in University (No. NCET-13-0169)+2 种基金the China Postdoctoral Science Foundation funded project (No. 2015T80360)the Heilongjiang Postdoctoral Fund (No. LBH-Z13083)the Open Project of State Key Laboratory of Urban Water Resource and Environment (No. ES201511-02)
文摘As a routine measurement to alleviate membrane fouling, hydraulic cleaning is of great significance for the steady operation of ultrafiltration(UF) systems in water treatment processes. In this work, a comparative study was performed to investigate the effects of the composition of backwash water on the hydraulic cleaning performance of UF membranes fouled by humic acid(HA). Various types of backwash water, including UF permeate, Milli-Q water, Na Cl solution, CaCl_2 solution and HA solution, were compared in terms of hydraulically irreversible fouling index, total surface tension and residual HA. The results indicated that Milli-Q water backwash was superior to UF permeate backwash in cleaning HA-fouled membranes, and the backwash water containing Na+or HA outperformed Milli-Q water in alleviating HA fouling. On the contrary, the presence of Ca^(2+) in backwash water significantly decreased the backwash efficiency. Moreover, Ca^(2+) played an important role in foulant removal, and the residual HA content closely related to the residual Ca^(2+) content.Mechanism analysis suggested that the backwash process may involve fouling layer swelling, ion exchange, electric double layer release and competitive complexation. Ion exchange and competitive complexation played significant roles in the efficient hydraulic cleaning associated with Na+and HA, respectively.