Kinetics of formaldehyde oxidation on a vanadia-titania catalyst

Abstract

The heterogeneous catalytic oxidation of formaldehyde in the gas phase may be considered as an alternative to the multistep liquid-phase synthesis of formic acid. Monolayer vanadia-titania catalysts are active and selective in the oxidation of formaldehyde to formic acid. Detailed investigation of kinetics of formaldehyde oxidation over a monolayer vanadia-titania catalyst was carried out. It was established that byproduct form via a consecutive-parallel reaction network. CO2 results from formaldehyde oxidation via parallel pathway and from formic acid overoxidation via consecutive pathway; CO forms from formic acid via consecutive pathway. It was shown that oxygen and water accelerate formic acid formation and that water retards CO formation. Based on experimental data, a kinetic model of formaldehyde oxidation was developed. The kinetic model was used in the mathematical simulation of the formaldehyde oxidation process and in the determination of dynamic and design parameters of the reactor. Formic acid production by the gasphase oxidation of formaldehyde is unique and does not have any analogue. As opposed to conventional technologies, it is energy-saving, environmentally friendly, and technologically simple. An enlarged-scale pilot plant using this technology is under construction.