改性聚四氟乙烯膜在油田含油污水中的表面ζ电位和电荷密度

对油田含油污水中不同孔径的改性聚四氟乙烯膜的流动电位进行了实验研究.根据Helmholtz-Smoluchowski方程算出改性聚四氟乙烯膜的微孔表面ζ电位,再根据Gouy-Chapmann方程,估算出膜表面的电荷密度.并对油田含油污水中悬浮颗粒的ζ电位进行了测定.结果表明:改性聚四氟乙烯膜表面带有负电荷,表面Zeta电位稳定在-20mV左右,而污水中悬浮颗粒ζ电位也为负值.由于膜表面电荷的作用,使膜具有更强的截留悬浮物颗粒及抗污染能力.

ζpotential and charge density on the membrane surface of the modified polytetrafluoroethylene in the oily sewage from oilfields

The streaming potential on the membrane surface of the modified polytetrafluoroethylene of different hole diameters in the oily sewage from oilfields are studied by experiments.The ζ potential of the membrane is estimated on the basis of Helmholtz-Smoluchowski equation,and then its surface charge density is estimated from the above ζ potential based on Gouy-Chapmann equation.The ζ potential of the suspended particles in the oily sewage from oilfields is measured.The experimental and the calculation results show that there is negative charge in the membrane surface,whose ζ potential maintains at-20 mV around.The ζ potential of the suspended particles in the oily sewage from oilfields is also negative.The membrane has stronger ability to retard the suspended particles in the oily sewage and to prevent pollution because of the charges on the membrane surface.