Effect of titanium dioxide nanoparticles on polydimethylsiloxane/polyethersulfone composite membranes for gas separation

Introducing inorganic nanoparticles into the structure of polymeric membranes is an interesting approach for the enhancement of physical, chemical, and separation properties of the membranes. In this article, the performance of a two‐layer nanocomposite membrane for gas separation was studied. Three different methods for embedding titanium dioxide (TiO 2 ) nanoparticle were employed for the membrane preparation. The techniques include blending TiO 2 in the polydimethylsiloxane (PDMS) coating layer, blending TiO 2 in the polyethersulfone (PES) support and dip coating of PES support with TiO 2 accompanied by PDMS coating. The aim of the current research was finding the optimum technique for introducing TiO 2 into the membrane to obtain superior performance for gas separation. The results indicated that PES support containing TiO 2 nanoparticles possessed favorable effect on gas separation capability. The optimum performance was obtained by PDMS‐coated membranes prepared with 7 wt% TiO 2 ‐embedded PES support. Carbon dioxide (CO 2 ) permeance, CO 2 /nitrogen, and CO 2 /methane selectivity were obtained as 188.7 GPU, 8.6, and 3.4, respectively. POLYM. ENG. SCI., 2012.