Methane pyrolysis on deposited resistive MeO x /carborundum catalysts, where MeO x is MgO, CaO, MgO/Al2O3, MgO/ZrO2, CaO/Al2O3, and CaO/ZrO2

Abstract

Thermostable oxide catalysts (Al2O3, ZrO2, MgO, and CaO) deposited onto a resistive support (carborundum) are investigated for oxygen-free methane pyrolysis. Adding MgO, ZrO2, and Al2O3 to pure carborundum considerably improves methane conversion and selectivity toward acetylene. In contrast, the deposition of СаO reduces the total activity of deposited catalysts. The maximum selectivity toward acetylene (23.6%) is achieved on MgO/SiC catalyst with methane conversion of 68% at T = 1290°C. Examination of the MgO/SiC sample shows that the catalyst retains its catalytic characteristics without decomposition (methane conversion, ≈69%; selectivity toward acetylene, ≈22%) for more than 4 h of operating in methane pyrolysis (15% СН4 in nitrogen) at a temperature of 1300°С as a result of there being no carbon corrosion of the carborundum resistive support, in comparison to the metal catalysts.