INVESTIGATION OF THE CATALYSTS OF FUEL COMBUSTION .15. THERMAL-STABILITY OF THE CEO2-AL2O3 SYSTEM

The dependences of the thermal stability of the Ce/Al2O3 system on tem perature (873-1573 K) and on the content of supported cerium (0-13 wt % CeO2) are studied by the x-ray diffraction method. The maximum therm al stability is shown to be reached when no more than 5 wt % of CeO2 i s introduced into the system. Contrary to the La2O3-Al2O3 system, the thermal stability of alumina is unaffected by the method used to intro duce cerium. Promotion of Al2O3 by cerium has less of a stabilizing ef fect on the support structure than does lanthanum. This phenomenon is due to a limited interaction between cerium and Al2O3.