Desalination by reverse osmosis using MFI zeolite membranes

This paper reports an experimental study on the reverse osmosis desalination of aqueous solutions using alpha-alumina-supported MFI-type zeolite membranes. A Na+ rejection of 76.7% with a water flux of about 0.112 kg m(-2) h(-1) was obtained for a 0.1 M NaCl feed solution under an applied pressure of 2.07 MPa. For a complex feed solution containing 0.1 M NaCl + 0.1 M KCl + 0.1 M NH4Cl + 0.1 M CaCl2 + 0.1 M MgCl2, rejections of Na+, K+, NH4+, Ca2+ and Mg2+ reached 58.1%, 62.6%, 79.9%, 80.7%, and 88.4%, respectively, with a water flux of 0.058 kg m(-2) h(-1), after 145 h of operation at an applied pressure of 2.4 MPa. (C) 2004 Elsevier B.V. All rights reserved.