Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

PP-IV-15carbon containing compounds. Reaction (1) need high temperatures > 500 °C and thecatalysts are ceria supported transition metals. The properties of supported ceria catalysts arevery sensitive to the ceria structure, particle sizes, and surface area.H 2 yield (H 2 mol/ethanol mol)2,52,01,51,00,50,0CeO25%Cu/CeO23%Cu/CeO210%Cu/CeO2400 450 500 550Temperature, 0 CFig. 1. H 2 yield over Cu/CeO 2 catalyst in steam reforming of ethanol (GHSV = 3000 h –1 ).Currently, we have developed the method based on ceria precipitation from water/alcoholmixtures producing near uniform ceria samples with high surface area and particle sizesbetween 4-8 nm. After incipient wetness impregnation of ceria with corresponding amount ofcopper nitrate, followed by calcination at 400 °C in air flow, a set of Cu/CeO 2 catalyst withdifferent copper loading was prepared. Their activities in the reaction (1) are presented onfig.1 and table 1. The best activities were achieved on in the range of 1-10% of copperloading with selectivity near 2 moles of hydrogen per one mole of ethanol. Obtained resultsshows that copper supported on nanocrystalline CeO 2 are promising catalysts for steamethanol reforming but the further development is needed to improve their selectivity to H 2 .Table 1. The products of ethanol conversion over Cu/CeO 2 at 500 °C (GHSV = 3000 h –1 ).Culoading,% wtC 2 H 5 OHconversion,%H 2Product composition, % molyield 1 ,% H 2 CO CO 2 CH 4 C-other 2none 70,0 16,6 46,0 0,3 20,3 10,6 22,80,5 28,7 11,9 58,0 0,2 22,2 6,4 13,21 90,1 29,1 51,5 0,2 23,0 8,4 16,93 93,5 28,8 51,0 1,3 22,5 6,9 18,35 84,6 30,5 54,0 0,2 23,1 7,3 15,410 63,4 30,3 59,0 0,8 22,6 8,1 9,520 54,0 16,0 52,0 0,3 22,2 4,9 20,630 57,2 18,7 52,0 0,3 22,8 7,9 17,01 The mole ratio of hydrogen formed and theoretical hydrogen yield2 including ethane, ethylene, acetaldehyde, acetone423