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Acetic acid production by selective oxidation of ethanol using Au catalysts supported on various metal oxide

2009; Springer Science+Business Media; Volume: 42; Issue: 4 Linguagem: Inglês

10.1007/bf03214954

0017-1557

Steton Moses Tembe, Gary Patrick, Michael S. Scurrell,

Catalysis and Hydrodesulfurization Studies

The liquid-phase oxidation of ethanol to acetic acid using Au catalysts supported on various metal oxides was studied at 150°C using molecular oxygen as stoichiometric oxidant. Catalysts containing 1 wt% Au supported on TiO2, Al2O3, and ZnO were examined for ethanol oxidation. The results showed that ZnO and TiO2 gave higher initial activities as supports for gold in ethanol oxidation, followed by Al2O3. Ethanol conversions of >90% and selectivities to acetic acid of >95% were achieved when using ZnO and TiO2 as supports under conditions where a slight oxygen deficiency was used. With a slight excess of oxygen present initially, ethanol conversions of 99.4%, and a selectivity to acetic acid selectivity of 99.8% could be achieved. Gold leaching seemed to be very apparent with alumina as support and also, after continued use with titania-based catalysts. The use of higher initial concentrations of ethanol (range studied 5–40 mass% ethanol in water) led to higher ethyl acetate selectivities. High acetic acid selectivities were seen for relatively low (5–10 mass%) initial ethanol concentrations.