| 摘要 |
<p>1278514 Porous alumina shapes KAISER ALUMINUM & CHEMICAL CORP 18 Sept 1969 [20 Sept 1968] 46098/69 Heading C1A Large surface area alumina shapes are formed by grinding a calcined alumina, having a loss on ignition of less than 12% by weight, mixing the finely divided alumina with water, contacting the aqueous alumina with bubbles, which form pores in the alumina, then shaping, curing and activating the alumina by heating. The bubbles may be formed by an agent which is gaseous between 0‹ and 100‹ C. such as air, nitrogen, CO 2 and fluorocarbons having a boiling point below 0‹ C. Alternatively, the agent may be a liquid which has a boiling point between 0‹ and 100‹ C., such as appropriate alcohols, ketones, ethers and chlorofluorocarbons. Hydrogen peroxide may also be used. A catalytic agent, such as Pt can be introduced at any stage of the process, for instance mixing an aqueous solution of a metal salt mixed with the slurry, or by immersion of or spraying the alumina shape formed.</p> |
