Preparation and reactive applications of nanoporous silicon carbide membranes

Abstract SiC nanoporous membranes have been prepared by chemical-vapor deposition/chemical-vapor infiltration of two different precursors, namely tri-isopropylsilane (TPS) and 1,3-disilabutane (DSB). Both precursors produce nanoporous membranes. The TPS-derived membranes are hydrothermally stable, while the DSB membranes produced, so far, are not. SiC nanoporous membranes have also been prepared by conventional dip-coating techniques using a novel pre-ceramic polymeric precursor allyl-hydridopolycarbosilane (AHPCS), a partially allyl-substituted hydridopolycarbosilane (HPCS). These membranes are stable in air-treatment at 450 °C, but have, so far, also proven unstable to high-temperature steam. The nanoporous hydrogen selective SiC membranes show promise for application in membrane reactors for the water gas shift and steam reforming reactions.