| Because energy sources are lessened and environmental pollution is becoming worse in the world. The cleaning gas fuel Cl-I4 is enlightened by the human people. Catalytic combustion offers great advantages over conventional combustion methods. During the past decades, research efforts have been promoted by the requirements concerning environmental protection and the wish to use energy source more efficiently. The catalytic material which meets the ektreme operative condition is the key technology . Al2O~ is a kind of porous, high dispersive solid material, which has big surface area . It' S Inicropore has catalytic effect property, such as adsorption, surface acid and so on. So make it as supported material.In this paper two deferent series Palladium supported catalysts were investigated. The first was prepared at 6OO~C. In this series A120-1 was pretreated by MO,(M~Zr, Fe, Ce, Mg), then Palladium was loaded on it, finally ealcined at 6000C, the catalysts of l%Pd/A1203, l%Pdl%Zr/A120, l%Pdl%Fe/A120.,, 1%Pdl%Ce/Al.O.,, l%Pdl%Mg/A120., were got. Then did activity, surface area, XRD, TEM, TPD, TG experiments separately. The activity experiment showed that the metal oxide addition promoted the catalyst' s activity greatly, especially the Mg addition. l%Pdl%Mg/Al,03 catalyst has high catalytic activity to ignite the methane combustion reaction at low temperature. The temperature of 10% transformation ratio to CU4 is 280'U, the completecombustion of methane is at 400'C. But l%Pd/A120~ catalyst' s T is 3600C. So the addition effect is excellent. The order of metal oxide effect is as below: Mg>Ce>Zr>Fe. In the deferent content of Mg addition experiment (the catalysts are 1%Pdl%Mg/Al20~, l%Pd2%Mg/Al20~, 1%Pd4%Mg/Al20~, l%PdS%Mg/Al203, 1%PdlO%Mg/A120.D, it showed the activity of catalyst decreased when the content of Mg addition increased. Especially when the content of Mg addition exceed 10% the activity of catalyst decreased greatly ,T11 is 34500. The catalyst calcined at 600X2 has big surface area. The area changes from 115m2/g to 165in2/g. we got the conclusion that the activity of catalyst is better with the surface area increasing.The second was caleined at l000XD. In this series A1201 was pretreated by M0jM~W, Ce, Zr, La, Mn, Ni, Mg, Fe), then Palladium of 1% was loaded on it, finally calcined at 100000, the catalysts of l%Pd/A1203, l%Pd1%1V/A1zO:~, 1%PdO. 5%Ce/ALO3, 1%PdI%Zr/A1203, 1%Pdl%La/A1203, l%Pdl%Mn/Al2O~, l%Pdl%NTi/A120.1, 1%Pdl%Mg/A120., and l%Pdl%Fe/Al20, were got. Then did activity, surface area, XRD, TEM, TPD, TG experiments separately. The activity experiment showed some metal oxide addition promoted the catalytic activity, the other restrained the catalytic activity. In them Mg, Fe, Zr, Ni promoted the catalytic activity; Ce, La, W, Mn restrained the catalytic activity. The catalyst pretreated by Mg addition has best activity in this series, it' s T10 is 365'C. The catalyst of 1%Pd/Al203' s T1,~ is 4050C. In addition lMgllAl, 2Mg1OA1 (lMgllAl expresses Mg and Almole ratio is 1:11.) were got using co-precipitator. lMgllAl calcined at 1200'C, 2Mg1OA1 calcined at 1000C. Then 1% Palladium was loaded on it, finally calcined at 100000. The activity experiment showed the 1%Pd/2Mg1OA1 has excellent activity, it' s T, is 32000. Comparison with 1%Pd/A120., calcined at l000C, it' s T0 decreased 8500. But the1%Pd/IMg11A1' s T10 is 41500. Because the lMgilAl was calcined at 120000 it produced a lot of a -A120-1. a -Al201 made the catalyst surfacearea decreased greatly. 1%Pd/2MglOAl' s area is 68. lm2/g, 1%Pd/lMgllAl' s is 13. 7m2/g.Comparison with two different series, we found the surface area and activity of Palladium supported catalyst are affected by calcinedtemperature greatly. The surface area of catalyst caicined at 600 00 changes from 115m2/g to 165m2/g, and the surface area of catalystcalcined at 1000 00 changes from 70m2/g to 90m'/g. contrast to l%PdlMg/AL03,caicjne~ at 6000C, surface area is 161.6m2/g; calcined at 100000, surface ar... |
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