Synthesis of highly active nano-sized (1 wt.% Pt/CeO2) catalyst for water gas shift reaction in medium temperature application

A simultaneous precipitation/digestion method has been developed to precipitate a crystalline cerium (III) carbonate (Ce-2(CO3)(3)center dot 8H(2)O) by a controlled reaction between aqueous solutions of Ce(NO3)(3)center dot 6H(2)O and K2CO3 at room temperature. The nano-sized CeO2 supports with crystallite size of 8.0 nm and high surface area of 131.6 m(2)/g were successfully prepared through a decomposition of a cerium (III) carbonate at 400 degrees C for 4 h. The digestion time was optimized to get highly active 1 wt.% Pt/CeO2 catalyst for the water gas shift (WGS) reaction. 1 wt.% Pt/CeO2 catalyst exhibited the highest CO conversion (82%) and 100% selectivity to CO2 at 320 degrees C at very high gas hourly space velocity (GHSV) of 45,625 h(-1) if an optimized digestion time of 4 h was used for the synthesis of cerium (III) carbonate. (C) 2011 Elsevier B.V. All rights reserved.