Dual catalyst bed for the oxidation of CH4 simultaneously to C2H4 and syngas

Abstract

Dual catalyst bed system was introduced into the conversion of methane in one reactor simultaneously to ethylene and syngas with appropriate concentrations, which could be used for further production of propanal via hydroformylation. To avoid the over consumption of O₂ on the first catalyst bed, the moderately active catalyst Co/γ-Al₂O₃ for methane partial oxidation was employed, followed by Na₂WO₄/Mn/SiO₂ catalyst, which was one of the most effective catalysts for the oxidative coupling of methane. The distribution of products could be tuned by controlling the relative dosages of the two catalysts and the reaction conditions. A mixture with the desired composition of CO/H₂/C₂H₄ = 1.1/1/1.2 was achieved, with the total yield of CO and C₂H₄ of about 18.5%, under the following optimized conditions: F = 150 cm³/min, CH₄/O₂ = 3, M₁:M₂ = 0.01 g:0.16 g (1: Co/γ-Al₂O₃; 2: Na₂WO₄/Mn/SiO₂). © 2007 American Institute of Chemical Engineers AIChE J, 2007