Catalytic combustion kinetics of acetone and toluene over Cu0.13Ce0.87Oy catalyst

Catalytic combustion kinetics of acetone and toluene at low concentrations in air over the previous Cu0.13Ce0.87Oy catalysts calcined at different temperatures was investigated in order to gain more insight into their catalytic behaviors. A differential packed-bed tubular reactor operated at atmospheric pressure was used to obtain the kinetic data. Reactions were carried out at temperatures between 423 and 483 K and organic compound partial pressures ranging from 10 to 101 Pa. Results showed that the simple power-law model was not enough to represent the kinetics of acetone or toluene combustion over the catalyst. The apparent reaction order and the apparent activation energy for acetone or toluene combustion over the catalyst varied with inlet compound partial pressure and reaction temperature, respectively. Based on the experimental evidence and available information in literature, a kinetic expression assuming reaction between adsorbed acetone and lattice oxygen was proposed to describe acetone combustion and a Langmuir–Hinshelwood (LH) equation assuming reaction between adsorbed toluene and adsorbed oxygen on different adsorption sites was used to account for toluene combustion. It was found that the kinetic equation derived from the mechanistic considerations provided fairly good fits to the kinetic data for catalytic combustion of acetone or toluene over the Cu0.13Ce0.87Oy catalyst. The estimated kinetic parameters of the Cu0.13Ce0.87Oy catalysts calcined at different temperatures were compared and the main difference among the three catalysts for acetone and toluene combustion was revealed.