STUDY ON THE DESALINATION BEHAVIORS OF PA/PSF THIN FILM COMPOSITE

A polypiperazine amide （PA）/polysulfone （PSF） thin film composite （TFC） was prepared by interracial polymerization （IP） using a trimesoyl chloride hexane solution as the oil phase and a piperazine aqueous solution as the water phase on a porous polysulfone hollow fiber substrate. Its separating behaviors were investigated systematically to various salts such as NaCl KCl, Na2SO4, MgCl2, CaCl2 and MgSO4, showing the highest rejection rate to Na2SO4, the second to MgSO4 the third to MgCl2 and CaCl2, and the lowest to KCI, NaCl, being 99%, 98%, 70%, 60%, 15% and 10% respectively. Under an increasing pressure or with time, the rejection rate of the TFC rises to a plateau. To various concentration of the feed, the rejection rate reduced gradually with the higher concentration.