Effect of hydrophilic Cu3(BTC)2 additives on the performance of PVDF membranes for water flux improvement

Abstract

In this study, a polyvinylidene fluoride (PVDF) membrane for water treatment was modified by dispersing hydrophilic metal–organic framework (MOF) particles, namely Cu3(BTC)2 and acidified Cu3(BTC)2, in a PVDF solution. The effects of the Cu3(BTC)2 and acidified Cu3(BTC)2 additives on the PVDF membranes were investigated in terms of hydrophilicity of the membrane surface and the water flux through the membrane. The PVDF membranes modified with hydrophilic MOF particles demonstrate improved water flux and maintain similar rejection values due to their improved hydrophilicity. Water fluxes of Cu3(BTC)2 and acidified Cu3(BTC)2 added membranes were 295.66 and 558 LMH which were 47 and 72.3% higher than those of the pure PVDF membrane, respectively. Acidified Cu3(BTC)2 was more stable and well immobilized in the PVDF membrane as no leaching of the metallic element was observed during the water permeation.