(630f) Partial Oxidation of Ethanol Over Platinum-Tin Catalysts for Hydrogen Generation

The objective of this work was to investigate Pt-Sn bimetallic catalysts on various supports like PSZ (Partially stabilized zirconia), alumina and cordierite for partial oxidation of ethanol. The effects of each catalytic system on hydrogen selectivity, conversion of ethanol were studied. The selectivity to ethane and ethylene was found to be higher for pure Pt than Pt-Sn on PSZ support. Amongst the Pt-Sn catalysts, Pt-Sn-PSZ demonstrated hydrogen selectivity of 40% which is higher than on Pt-Sn-alumina and Pt-Sn-cordierite. The changes in selectivity was attributed to good active-metal support interactions which was characterized using temperature programmed technique and pulse-chemisorption. The reduction of platinum, tin and platinum-tin alloy were found to be favored on PSZ than the other two supports which was evident from Temperature programmed reduction profile. Pulse-Chemisorption shows that the active particle diameter was 25 nm on PSZ which is much smaller than alumina (270 nm) and cordierite (111 nm) . The metallic surface area achieved on PSZ was 18 m2/g metal which was higher than observed on alumina and cordierite. Overall, hydrogen selectivity, ethanol conversion was found to be better at all C/O ratios for Pt-Sn-PSZ than Pt-Sn- alumina and Pt-Sn-cordierite. As the second phase of the project plasma surface modification of the ceramic monoliths was achieved using nitrogen. TPR data shows that plasma surface modification introduced new phases of platinum and tin in the system which may contribute to definite changes in the product selectivities and conversion of ethanol.