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How to get the large specific surface, good thermal stability, and high catalytic activity of methane combustion catalyst is still unresolved issues. A melting point of MgO up to 2850 ° C, and other oxides, at high temperatures has a large specific surface area, so MgO is considered to be used as a carrier of the catalyst at high temperature. La, Ce, Y, Mn, Cr, Cu and other metal affect the literature has not been reported for the performance of the supported catalyst of MgO, so our system studied rare earth element and a transition metal as additives NiO / MgO catalyst activity and stability. The main results are as follows: 1. Using the sol-gel method of NiO / M x -MgO the O y (M = Ce, Cu, Cr, La, Y,, Mn Ti) catalyst. M additives NiO / MgO catalyst for methane combustion performance. Aid of M different degree to improve the activity of the catalyst of NiO / MgO, wherein the Cu, Mn-modified catalyst activity is preferably, but poor stability; La, Ce, Y modified catalyst activity center, better stability. BET, XRD, TEM test results further show that while the sintered Cu, Mn-modified catalyst after the second evaluation; La, Ce, Y-modified catalyst having a larger specific surface area, and good resistance to sintering ability, wherein Y the modified catalyst stability. 2.Y content of the Nio / (Y 2 O 3 ) x - (MgO) 1-2x catalyst The activity of the best ratio of x = 0.075 the best catalyst activity. Nio / (Y to the 2 O 3 ) 0.075 - (MgO) 0.85 catalyst aging at 1000 ℃ for 5h still has a high catalytic activity, and good thermal stability. Series M (= Ni, Co, Cu) / (CeO 2 ) x - (Mgo) 1-x catalysts for methane combustion The performance impact of investigation. Ce content Nio / (CeO 2 ) x - (MgO) 1-x catalyst activity there are also the best ratio, when at x = 0.1, the catalyst activity and stability of the best. Have a great impact to (CeO 2 ) 0.1 - (MgO) 0.9 load a different active ingredient as the carrier of the catalyst for methane combustion performance best load of Cu catalyst activity, but after the second evaluation. catalyst sintered; activity supported Ni catalysts supported Cu catalysts or less, and the best stability; supported Co catalyst activity than the first two, stability center, surface area reduction at least, anti-sintering ability. 1000 ° C calcined NiO / (CeO 2 ) 0.1 - (MgO) , 0.9 catalyst by second evaluation, the structure of the catalyst did not happen any change to achieve stability. The surface area of ??the catalyst 14.32m 2 · g -1 , has high catalytic activity and good thermal stability.
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