Catalytic performance of Rh/CeO2 in the gasification of cellulose to synthesis gas at low temperature

The gasification of cellulose has been investigated on Rh catalysts supported on CeO2, ZrO2, Al2O3, TiO2, MgO, and SiO2 at very low temperatures (723-823 K) in a laboratory-scale fluidized-bed reactor using air as a gasifying agent. Of the catalysts, only Rh/CeO2 showed the excellent catalytic performance in the cellulose gasification at above 823 K, resulting in 100% carbon conversion to gas. The details of reaction conditions that affected the performance of the catalyst have been optimized. The best results have been found at above 823 K using the total flow rate of 170 cm(3) min(-1) of inlet gases. The total carbon conversion was achieved when 50 mg of cellulose was used in a batch. The Rh loading of 1.2 x 10(-4) mol (g of catalyst)(-1) on CeO2 and W/F of 1.8 gh mol(-1) were optima for the total conversion of carbon to gases. Fresh and used catalysts were characterized by a Brunauer-Emmett-Teller (BET) analysis and transmission electron microscopy (TEM). The BET surface area has been decreased from 59 to 24 m(2)/g during the first batch reaction; however, this value decreased to 21 m(2)/g during the next 20 batches. No Rh particle was observed in the TEM image of the fresh catalyst; however, in the used catalyst, it was observed, and the particle size was 1.5-2.2 nm on CeO2.