Steam reforming of acetone over NiCoMgAl mixed oxide catalysts obtained from hydrotalcite precursors

Abstract

Layered double hydroxides obtained via co-precipitation method possess a kind of hydrotalcite structure comprising Ni2+/Co2+/Mg2+/Al3+cations in various amounts. Upon calcination of the hydrotalcite precursor, NiCoMgAl mixed oxides catalysts of varying Ni:Co ratio (0.3, 1.0 and 3.0) were obtained. These catalysts were tested for steam reforming of acetone at temperatures between 450 and 550 °C, with a molar feed (water/acetone) ratio of 4–10 and in the space-time range of 10–24 kg cat h/kmol acetone. Around 99% conversion of acetone was obtained over all the mixed oxide catalysts. However, a maximum hydrogen selectivity of ∼80% was obtained over NiCoMgAl(0.33). The time-on-stream behaviour was studied for 4 h at 500 °C and water/acetone molar ratio of 6. The catalyst showed good stability at the reforming conditions. Both homogeneous and heterogeneous kinetic models were developed for the complex reforming reaction systems.