| 摘要 |
PURPOSE:To obtain the titled composition which continues to hold a high surface area even if exposed at high temp. for a long period and has the heat resistance by adding a basic compd. to a mixed aq. soln. of Al2O3 hydrate and colloidal SiO2, thickening and gelatinizing the mixture, drying and calcining the obtained gelatinized material. CONSTITUTION:A basic compd. such as an aq. NH3 soln. or aliphatic amines is added to a mixed aq. soln. of both Al2O3 hydrate which is amorphous and has the partial solubility for an acid and collidal SiO2 and the mixture is regulated to 7-10pH, thickened and gelatinized by performing the kneading and the stirring at 10-150 deg.C temp. region. Then gel wherein SiO2 is uniformly dispersed to Al2O3 is dried, crushed and thereafter calcined. Since the aimed composition consisting of a composite oxide of Al2O3 and SiO2 obtained by such a way is thermally stable even if exposed at >=1,000 deg.C for a long period, it is available as a carrier of the catalytic combustion and the purification of exhaust gas of an automobile.
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