Publication Date:
2012-12-13
Description:
The catalytic activities of Cu/MO x (MO x = Al 2 O 3 , TiO 2 , and ZnO) catalysts in the gas-phase hydrogenolysis of glycerol were studied at 180–300 °C under 0.1 MPa of H 2 . Cu/MO x (MO x = Al 2 O 3 , TiO 2 , and ZnO) catalysts were prepared by the incipient wetness impregnation method. After reduction, CuO species were converted to metallic copper (Cu 0 ). Cu/Al 2 O 3 catalysts with high acidity, high specific surface areas and small metallic copper size favored the formation of 1,2-propanediol with a maximum selectivity of 87.9 % at complete conversion of glycerol and a low reaction temperature of 180 °C, and favored the formation of ethylene glycol and monohydric alcohols at high reaction temperature of 300 °C. Cu/TiO 2 and Cu/ZnO catalysts exhibited high catalytic activity toward the formation of hydroxyacetone with a selectivity of approx. 90 % in a wide range of reaction temperature. In gas-phase hydrogenolysis of glycerol, Cu/Al 2 O 3 catalysts with high acid strength of weak and strong acid sites and small-sized metallic copper favored the formation of propanediols, ethylene glycol and monohydric alcohols. Cu/TiO 2 and Cu/ZnO catalysts with low acid strength of weak acid sites and large-sized metallic copper favored the rapid dehydration of glycerol to hydroxyacetone.
Print ISSN:
0930-7516
Electronic ISSN:
1521-4125
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
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