TiO_2改性Al_2O_3微滤膜荷电性及其对膜水通量的影响  

SURFACE ELECTRIC CHARGE OF Al_2O_3 MICROFILTRATION MEMBRANE MODIFIED BY TiO_2 AND ITS INFLUENCE ON WATER FLUX OF MEMBRANE

作　　者：周健儿[1] 张小珍[1] 汪永清[1] 胡学兵[1] 梁健[1] 

机构地区：[1]景德镇陶瓷学院,景德镇333000

出　　处：《中国陶瓷》2007年第4期7-9,14,共4页China Ceramics

摘　　要：以硫酸钛、尿素为主要原料,采用均相沉淀法在Al2O3微滤膜孔表面成功制备了一层纳米TiO2改性涂层。采用显微电泳法通过测定Al2O3微滤膜颗粒表面TiO2涂层的zeta电位表征了TiO2涂层改性Al2O3微滤膜表面的荷电性,并探讨了微滤膜荷电性其对其水通量的影响。宏观电泳测试和Zeta电位分析表明,经TiO2改性后,Al2O3微滤膜表面荷电性能发生了明显改变,未改性膜Zeta电位等电点为pH=6.3,而改性后膜在pH=2～12时均荷负电。经TiO2改性Al2O3微滤膜的纯净水渗透通量较未改性时明显提高;当pH=6.6时,经TiO2改性后Al2O3微滤膜表面zeta电位绝对值的变化规律与相应的改性Al2O3微滤膜的纯净水渗透通量的变化趋势完全一致,表明微滤膜水过滤通量的提高与改性涂层改变了膜孔表面的电动性质密切相关。For the modification of α-Al2O3 microflitration membrane, the nano-crystalline TiO2 coating was prepared by homogeneous precipitation method using titanium sulfate and urea as raw materials. The obtained coating was dense and composed of 15-20nm TiO2 particles. The surface electric charge of Al2O3 microfiltration membrane modified by TiO2 was characterized by measuring the zeta potential of TiO2 coating on constituent particles of the membrane through microelectrophoresis. The influence of membrane surface zeta potential on the water permeate flux of Al2O3 membrane was explored. It is found that the surface electric charge condition of Al2O3 membrane has been changed obviously after modifying by nano-crystalline TiO2 coating, through macroscopical electrophoresls testing and zeta potential measurement. The isoelectric point is at pH=6.3 for unmodified Al2O3 membrane, but Al2O3 membrane modified by TiO2 coating is negative electric charged with pH value ranging from 2 to 12. The purified water permeate flux of Al2O3 microfiltration membrane modified by nano-sized TiO2 increases apparently, comparing to the unmodified. The absolute value of surface zeta potential of Al2O3 microfiltration membrane modified by TiO2 shows the same change trend as the corresponding water permeate flux of modified membranes. The increasing of purifying water flux for modified membrane is closely related to the change of membrane electric kinetic characteristic resulted from the TiO2 modifying coating.

关 键 词：TIO2涂层 AL2O3 微滤膜 表面荷电性 水 通量 

分 类 号：TQ174.758[化学工程—陶瓷工业]