Studies on oxidative dehydrogenation of n-butane on bismuth molybdate-aluminium phosphate catalysts. II. Activity and selectivity

Olefins and diolefins are important intermediates in the petrochemical industry, and the future promises a further substantial increase in demand. Several catalysts have been formulated in the past for the abstraction of hydrogen from butenes and propylene. However, these catalysts are inefficient in the abstraction of first hydrogen from n-butane. Bismuth molybdates (β- and γ-phases) on aluminium phosphate have been found to be good catalysts for the oxidative dehydrogenation of n-butane. Optimal conditions for the yield of (butene+butadiene) have been established in the ranges of variables studied, using response surface methodology and the following ranges of experimental conditions: temperature, 400 to 500°C; W/F (catalyst to feed ratio), 0.25 to 2.5g/(mg mol/min); butane to oxygen ratio, 0.5 to 2.0mol/min; bismuth molybdate to o-AIPO4 ratio, 0 to 100mol/100 mol. A maximum yield of approximately 13% (butenes+butadiene) was obtained in the ranges of experimental variables studied.