Abstract
A plate-type nickel catalyst on an aluminum plate prepared by electroless plating, which consisted of displacement of aluminum with zinc and the deposition of nickel by chemical reduction, has high activity and high selectivity to form hydrogen and carbon monoxide for methanol decomposition. This nickel catalyst, then would be suitable for a plate-type catalyst for the construction of a wall reactor system, which has an effective exchange of heat energy, a quick load response due to a low pressure loss and a downsized dimension of the reactor. In this study, in order to accumulate any kinetic information and derive the reaction rate equation for constructing the wall reactor system, a kinetic study for methanol decomposition on the plate-type nickel catalyst prepared by electroless plating was conducted at 533–623 K and atmospheric pressure.
The reaction rate equation revealed that a methanol molecule is strongly adsorbed on the plate-type catalyst surface, forming a methoxy species (CH3O-), and the rate-determining step involves the abstraction of hydrogen from the adsorbed methoxy species. Furthermore, the reaction rate was depressed by the introduction of carbon monoxide in the reaction feed, but was not affected by that of hydrogen. By assuming the Langmuir–Hinshelwood mechanism, the integrated rate equation is derived from the obtained kinetic data in fitting parameters, such as the constant of the reaction rate and adsorption equilibrium for methanol, hydrogen, and carbon monoxide, by means of the Simplex method. The derived rate equation is well expressed with each experimental result.
