Blend polyethersulfone/zirconium oxychloride octahydrate membranes crosslinked by polyvinyl alcohol layer for high saline water desalination

Abstract

Abstract Mixed matrix membranes were prepared by blending polyethersulfone with zirconium oxychloride octahydrate (ZOH) solution, and coating by polyvinyl alcohol layer. Different analyses were applied in the prepared membranes. Membranes performances were examined using different salty solutions concentrations (5000, 10,000 and 20,000 mg/L) and a real sample from highly concentrated seawater (brine) of 1,30,900 mg/L. The results indicate that blending polyethersulfone with 1.5% ZOH and coating with polyvinyl alcohol (PVA) cross-linking layer (M4) provides salt rejection of 99.9% with permeate flux of 32.4 L/m2.h for the salt solution of 5000 mg/L, while salt rejection was 92% with permeate flux of 11.1 L/m2.h for the salt solution of 1,30,900 mg/L. The results indicate enhancement in the hydrophilicity of the membranes especially after coating by the PVA layer and increasing the ZOH%, such as the high permeate flux and the lowest contact angle of prepared membrane M4 (1.5% ZOH) which was 39.7°. A long time experiment was applied on the prepared membrane (M4), where the results indicate that the permeate flux for a long time was approximately fixed for 120 h, which indicates that the membrane can be considered as a self-cleaning membrane.