A kinetic model for partial oxidation of ethane to acetic acid on promoted VPO catalyst

The partial oxidation of ethane to acetic acid on promoted VPO with Mo, using an Mo/V ratio of 0.2, has been investigated experimentally and theoretically. The reaction was carried out in a differential reactor at 1360 kPa, in the temperature range 548–623 K, with space times of 1.2–3.6 s and oxygen concentrations of 5–20%. The rate of oxidation of ethane was found to be approximately first order in ethane and zero order in oxygen at 548 K. At 623 K, the order of reaction with respect to ethane decreased to about 0.5, while that for oxygen increased to about 0.27. A kinetic model has been developed, which assumes that adsorbed oxygen reacts with ethane to form ethene, acetic acid, CO and CO2. Ethene is further oxidized to acetic acid, CO and CO2 through a redox mechanism. The model exhibits good agreement with the experimental data. © 2000 Society of Chemical Industry