| 摘要 |
A catalyst composition suitable for catalysing the reaction of propylene with oxygen comprises antimony tetroxide in combination or in admixture with stannic oxide. The catalyst composition may be found by heating a mixture of antimony tetroxide and stannic oxide at 550 DEG -1,100 DEG C. Alternatively at least one of the oxide, stannous oxide, stannic oxide and the hydrated oxide which is obtained by the action of aqueous nitric acid on tin metal is heated at 550 to 1,100 DEG C. with at least one of the oxides antimony trioxide, antimony tetroxide, antimony pentoxide and the hydrated oxide which is obtained by the action of aqueous nitric acid on antimony metal in the presence of oxygen. Again, aqueous nitric acid may be added to a mixture of tin and antimony metals, the hydrated oxides of tin and antimony thereby formed being heated at 550 DEG -1,100 DEG C. in the presence of oxygen. The antimony and/or tin oxide constituent(s) may be formed by hydrolyzing with water a cationic salt of the metal, e.g. SbCl5, SnCl4 or a mixture thereof, and heating the resulting precipitate at 550 -1,100 DEG C. preferably in the presence of a volatile base, e.g. ammonia. Catalyst supports mentioned are silica, silica gel and graphite. Examples are given. The catalyst composition may be used for the conversion of methanol to hydrogen cyanide in the presence of ammonia and molecular oxygen. Specifications 864,660 and 876,446 also are referred to.ALSO:A catalyst composition comprising antimony tetroxide in combination, or in admixture with stannic oxide is suitable for catalysing the following reactions:-(1) propylene and oxygen to give acrolein (2) oxidative dehydrogenation of butene to butadiene in the presence of molecular oxygen (3) the oxidative dehydrogenation of methyl-butene to isoprene in the presence of molecular oxygen and (4) the conversion of propylene to acrylonitrile and isobutene to methacrylonitrile in the presence of ammonia and molecular oxygen. Examples are given one of which describes the conversion of isobutene to methacrolein. Specifications 864,666 and 876,446 also are referred to. |
