Conversion of ethane to acetaldehyde by partial oxidation with oxygen over BPO4-based catalysts

Abstract

Direct conversion of ethane to acetaldehyde by partial oxidation with oxygen proceeds selectively on BPO₄ modified with basic oxides.

The contribution of homogeneous reactions in the gas phase to the catalytic process can be neglected under the experimental conditions of this work. The kinetic results obtained for ZnO-added BPO₄ suggest that CH₃CHO and C₂H₄ are produced in parallel via a common reaction intermediate. This intermediate was assumed to be ethyl peroxide formed from an ethyl intermediate and O₂.

The role of basic oxides is to increase the basicity of the active site —B—O—, resulting in an increase in the rate of heterolytic splitting of C—H bond on the site.

The NH₃ temperature-programmed desorption (TPD) studies have suggested a weakening of the acidic strength of the host BPO₄ catalyst by addition of ZnO, MgO and CaO. This modification decreases the apparent activation energy of the conversion of C₂H₆, especially for the conversion to CH₃CHO.