Ion separation by Reverse Osmosis on MFI zeolite Membranes

摘要

Separation of ions from aqueous solutions has been performed by reverse osmosis (RO) on α-alumina-supported MFI-type zeolite membranes synthesized by in situ crystallization. The effects of ion valence, hydrated ion size, and the operation temperature on the ion diffusion, water permeation and separation efficiency were investigated. For the 0.1M metal chloride single-salt solutions, the separation efficiency in terms of ion rejection was found to increase with the ion valances in the order rAl3+＞rMg2+＞rNa+,while the ion and water fluxes changed in the reverse order. For a multicomponent solution containing NaCl, KCl, NH4Cl, CaCl Cl, CaCl2 and MgCl MgCl2, both the ion and water fluxes increased with increasing the operation temperature.