Particle/metal-based monolithic catalysts dual-bed reactor with beds-interspace supplementary oxygen: Construction and performance for oxidative coupling of methane

Abstract

A novel particle/metal-based monolithic catalysts dual-bed reactor with beds-interspace supplementary oxygen is constructed comprising of the upper-layer 5 wt%Na₂WO₄-2 wt%Mn/SiO₂ particle catalyst and the under-layer 3 wt%Ce-5 wt%Na₂WO₄-2 wt%Mn/SBA-15/Al₂O₃/FeCrAl metal-based monolithic catalyst as well as a side tube in the interspaces of two layers for supplementing O₂. The reaction performance of oxidative coupling of methane (OCM) in the dual-bed reactor system is evaluated. The effects of the reaction parameters such as feed CH₄/O₂ ratio, reaction temperature and side tube feed O₂ flowrate on the catalytic performance are investigated. The results indicate that the suggested mode of dual-bed reactor exhibits an excellent performance for OCM. CH₄ conversion of 33.2%, C₂H₄ selectivity of 46.5% and C₂ yield of 22.5% could be obtained, which have been increased by 6.4%, 4.1% and 5.5%, respectively, as compared with 5 wt%Na₂WO₄-2 wt%Mn/SiO₂ particle catalyst in a single-bed reactor and increased by 10.7%, 31.9% and 17.7%, respectively, as compared with 3 wt%Ce-5 wt%Na₂WO₄-2 wt%Mn/SBA-15/Al₂O₃/FeCrAl metal-based monolithic catalyst in a single-bed reactor. The effective promotion of OCM performance in the reactor would supply a valuable reference for the industrialization of OCM process.