Insights into the enhanced performance of ignition and self-sustained combustion of n-decane over Co3O4-based catalysts

Abstract

Aiming to achieve efficient utilization of high-energy–density fuels in the promising portable power systems, self-sustained combustion of n-decane over Co3O4-based catalysts in a narrow quartz reactor was investigated. Chemiluminescence, gas chromatography and various physicochemical characterization methods were used in this study. The evidences suggest that Co3O4-based catalysts can significantly reduce the ignition temperature and broaden the flammability limits of n-decane. The heat release stored in the catalyst bed can help improve the flame stability, delay the flame extinction, and achieve auto-ignition without forced heating. Besides, great promotion of the catalytic performance of Co3O4 spinel is achieved by doping with 6 wt% PdO. PdO/Co3O4 catalysts exhibit higher activity and enhanced ability in effectual resistance toward deactivate than pure Co3O4. Furthermore, the coupling of heterogeneous and homogeneous reactions of n-decane has been analyzed. It can be revealed that both the adsorbed and gaseous OH* radicals play greatly different roles when using different catalysts. These findings promote the use of heavy hydrocarbon fuels for energy supply and contribute to designing efficient Co3O4-based catalysts rationally.