Polysulfone(PS)hollow-fiber ultrafiltration membrane was characterized combined with flux and streaming potential in single electrolyte solutions.The effects of trans-membrane pressure,electrolyte concentration,ion va...Polysulfone(PS)hollow-fiber ultrafiltration membrane was characterized combined with flux and streaming potential in single electrolyte solutions.The effects of trans-membrane pressure,electrolyte concentration,ion valence and pH value of electrolyte solution on the streaming potential(SP)of the membrane were investigated.The zeta potential and surface charge density of the membrane were calculated on the basis of Helmholtz-Smoluchowski equation and Gouy-Chapmann theory.The results indicate that the valence and concentration of cation have a greater influence on the SP and surface charge density of PS membrane than those of anion,and the pH value of electrolyte solution has great effects on the SP and zeta potential of the membrane surface. Both the absolute value of the streaming potential and water flux of the adsorbed membrane decrease,compared with those of the clean membrane.The streaming potential and flux of the cleaned membrane can be completely recovered by cleaning with the mass fraction of 0.8%EDTA at pH=10.展开更多
The streaming potential of poly(vinyl butyral) (PVB) hollow fiber membrane was studied in different electrolyte solutions (including NaCl, KCl, CaCl2 and MgCl2), the effects of ionic strength, ion valence and pH...The streaming potential of poly(vinyl butyral) (PVB) hollow fiber membrane was studied in different electrolyte solutions (including NaCl, KCl, CaCl2 and MgCl2), the effects of ionic strength, ion valence and pH value on the streaming potential (SP) of the membrane were investigated. The zeta potentials and surface charge densities of the membrane were estimated on the basis of Helmholtz-Smoluchowski equation and Gouy-Chapmann theory. The results show that the PVB membrane has a weak negative charge due to the specific adsorption of ions. Moreover, the streaming potential, the zeta potential and the surface charge density of the membrane depend strongly on the salt concentration and the type and valence of ions. The iso-electric point (IEP) of the PVB membrane is arotmd 3.0 in the monovalent media (NaC1 and KC1) and 3.5 in divalent electrolytes (CaCl2 and MgCl2). A few retentions were obtained for PVB membrane in low concentration solutions. This result verifies that the negative charged membrane surface can reject inorganic solutes by means of electrostatic repulsion effect even though the size of membrane pores is much larger than the size of salts.展开更多
基金Project(20776161)supported by the National Natural Science Foundation of China
文摘Polysulfone(PS)hollow-fiber ultrafiltration membrane was characterized combined with flux and streaming potential in single electrolyte solutions.The effects of trans-membrane pressure,electrolyte concentration,ion valence and pH value of electrolyte solution on the streaming potential(SP)of the membrane were investigated.The zeta potential and surface charge density of the membrane were calculated on the basis of Helmholtz-Smoluchowski equation and Gouy-Chapmann theory.The results indicate that the valence and concentration of cation have a greater influence on the SP and surface charge density of PS membrane than those of anion,and the pH value of electrolyte solution has great effects on the SP and zeta potential of the membrane surface. Both the absolute value of the streaming potential and water flux of the adsorbed membrane decrease,compared with those of the clean membrane.The streaming potential and flux of the cleaned membrane can be completely recovered by cleaning with the mass fraction of 0.8%EDTA at pH=10.
基金Project(21176264)supported by the National Natural Science Foundation of ChinaProject(11JJ2010)supported by the Hunan Provincial Natural Science Foundation of China+1 种基金Project(CL11096)supported by the Undergraduate Innovation Training Foundation of Central South University,ChinaProject(BL12053)supported by the Undergraduate Innovation Training Foundation of Hunan Province,China
文摘The streaming potential of poly(vinyl butyral) (PVB) hollow fiber membrane was studied in different electrolyte solutions (including NaCl, KCl, CaCl2 and MgCl2), the effects of ionic strength, ion valence and pH value on the streaming potential (SP) of the membrane were investigated. The zeta potentials and surface charge densities of the membrane were estimated on the basis of Helmholtz-Smoluchowski equation and Gouy-Chapmann theory. The results show that the PVB membrane has a weak negative charge due to the specific adsorption of ions. Moreover, the streaming potential, the zeta potential and the surface charge density of the membrane depend strongly on the salt concentration and the type and valence of ions. The iso-electric point (IEP) of the PVB membrane is arotmd 3.0 in the monovalent media (NaC1 and KC1) and 3.5 in divalent electrolytes (CaCl2 and MgCl2). A few retentions were obtained for PVB membrane in low concentration solutions. This result verifies that the negative charged membrane surface can reject inorganic solutes by means of electrostatic repulsion effect even though the size of membrane pores is much larger than the size of salts.