Experimental Investigation Of Catalytic Combustion Characteristics Of Methane On Pd-based Catalysts

In 2009, China has a coal production of 30.5 million tons and the volume of pure methane discharged through ventilation during coal mining is between 15 and 20 billion cubic meter. Methane is one of the most difficult oxidized hydrocarbons and its greenhouse effect is 20 times bigger than carbon dioxide with the same mass. So now when the requirement of environmental protection is growing, the research and development of technology using ventilation gas is very significant. Because of the low methane concentration in ventilation gas (usually <1%), conventional combustion methods can't be used to utilize the methane. Also it's unfeasible for traditional pressure swing adsorption or temperature swing adsorption methods, because more energy would be consumed.Currently, ventilation gas can only be used by thermal oxidation, catalytic oxidation or utilized as auxiliary fuel at home and abroad. How to get efficient catalyst is the most important question in the technology of catalytic oxidation. The catalyst for methane catalytic combustion mainly contains Pd, Pt, Rh, Au and others. Among which, Pb becomes a research focus for its good low temperature burning activity, activity stability, and high methane conversion.In this paper, the modified Pd/γ-Al₂O₃ impregnated catalysts are used in low-temperature combustion of ventilation gas. From the view of basic application, the catalytic combustion activity of Pb catalysts are studied and optimally selected through changing Pd loadings, calcination temperature, concentration of methane, reaction space velocity and additives, etc. On the basis of above results, the resistance of catalysts to sulfur poisoning is investigated. Furthermore, thermal analysis technique is used to analyze the ability of sulfur poisoning before and after catalyst curing.The results show that supported Pd catalyst after a certain optimization selection can meet practical needs of ventilation gas application in industry. The technology has a certain environmental and economic benefits. Also it offers one possible solution for the treatment of Ventilation gas.