| 摘要 |
Metal oxides in microspherical form are prepared by hydrolyzing with steam a solution of metal alcoholate, phenolate, or cresylate in the form of liquid microspheres. The solution may be sprayed into the top of a vertical contacting zone, superheated steam introduced at the lower part of the zone, and the metal oxide particles withdrawn from the bottom of the zone and dried. Alcohol, phenol, or cresol vapours leaving the contacting zone are condensed, separated from water, and used to react with a metal or alloy to reform the alcoholate, phenolate, or cresylate solution. Oxides of Al, Mg, Zn, Ti, Ca, A, Mn, or mixtures of these oxides, may be produced. Examples describe the formation and hydrolysis of solutions of aluminimum amylate, zinc and aluminium phenolates, and zinc and aluminium cresylates to form alumina, and zinc oxidealumina. The alumina is useful as a catalyst or absorbent, and may be impregnated with solutions of molybdenum or chromium compounds to form hydroforming catalysts, or mixed with silica to form cracking catalysts. The zinc oxidealumina, either alone or treated with molybdenum or chromium compound solutions, is also useful as a hydroforming catalyst. Silica-alumina may be prepared by adding a hydrolysable silicon compound, e.g. ethyl silicate, to the aluminium alcoholate, phenolate, or cresylate solution. Mixed oxide may also be prepared by adding metallic soaps, e.g. naphthenates, oleates, palmitates, or stearates of Cr, Ni, Fe, Cu, Mn, Pb, Mo, or Co, to the solution to be hydrolized. Specification 719,723 is referred to.
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