Applied Studies On Methane Catalytic Combustion

The influences of E dopant and preparation method on the Oxygen Storage Capacity (OSC) of CeO₂-ZrO₂ Oxygen Storage Materials (OSM) have been investigated. The effects of the OSM as a support material component have been studied, and the active catalysts of transition metal oxides such as Co₃O₄,Fe₂O₃ and MnO₂ have been optimized on purpose. The results show that different preparation methods have large effect on the OSC of OSM. The fresh samples prepared by coprecipitation method haven't the largest OSC and specific surface area, but they have the best thermal stability—after aged at high temperature, they have the largest OSC and specific surface area. Among the CeO2-ZrO₂ solid solutions with different E addition, The OSM containing 20% E exhibited the best thermal stability, the highest OSC after ageing. We found that YSZ-Al₂O₃+OSM was a kind of good support for methane combustion catalysts. The Co-Fe-Mn/YSZ-Al₂O₃+OSM catalyst exhibited high catalytic activity and good thermal stability. A natural gas catalytic premixed Burner for Household Applications has been developed on the basis of such methane combustion catalyst deposited over ceramic monolith honeycomb substrate. We optimized the other important parameters such as diameter of the nozzle, height and structure of the bracket, height of the catalyst washcoat, etc. the catalytic premixed burner and the reference noncatalytic burner were comparatively tested, and inspected by China Quality Supervising And Test Center for Gas Appliances (CGAC). The results show that the catalytic domestic gas appliance have the advantages of higher thermal efficiency, lower CO or NOx emissions and lower noise. So it's a kind of energy saving and environment friendly product with high efficiency. A natural gas catalytic premixed boiler prototype for Household Applications has been developed on the basis of such methane combustion catalyst system. We optimized the other key component such as firebox, heat-exchanger, and the other important parameters such as thickness of the ceramic board, height of the catalyst washcoat, working voltage of the fan, specific capacity, etc. The catalytic domestic gas water-heater and the reference noncatalytic gas water-heater were comparatively tested. The results show that catalytic domestic gas water-heater have the advantages of higher thermal efficiency, lower CO or NOx emissions. So it's also a kind of energy saving and environment friendly product with high efficiency.