摘要:
A process for producing an antimony-containing oxide catalyst with improved strength is described, by the steps of preparing a slurry containing an antimony compound, a polyvalent metal compound and a silica sol as the essential ingredients, adjusting the pH of the slurry to 7 or less, heat treating the slurry at a temperature of 40.degree. C. or higher, and thereafter drying the slurry and calcining the dried particles, wherein said slurry is irradiated with ultrasonic waves during the pH adjustment, or after the pH adjustment and before completion of the heat treatment.
摘要:
A method for producing an aqueous silica sol is described, comprising admixing a fine silica powder having an ultimate particle size of 5 to 200 millimicrons with an aqueous medium at a pH not higher than 5 while applying ultrasonic vibrations having a frequency within the range of from 10 to 100 kilohertz to the aqueous medium to thereby disperse said silica powder in said aqueous medium and thus convert the mixture into an aqueous sol.
摘要:
A process for producing an antimony-containing oxide catalyst supported on silica for use in a fluidized bed reaction is described, by the steps of preparing a slurry containing an antimony compound, a polyvalent metal compound, and silica sol as the essential ingredients, heat treating the slurry at a pH of 7 or less and at a temperature of 40.degree. C. or higher, and thereafter spray-drying the slurry and calcining the dried particles, wherein said silica sol has a multi-peak particle size distribution profile that is derived by using a mixture of silica sol A in an amount corresponding to form 10 to 90 wt % of the total silica in the catalyst and silica sol B in an amount corresponding to 90 to 10 wt % of the total silica in the catalyst, with silica sols A and B having different average particle sizes, provided that the relations 3
摘要:
Iron-antimony metallic oxide catalysts which have become deactivated after being used for the production of aldehydes, acids, nitriles, or dienes through oxidation, ammoxidation, or oxidative dehydrogenation of organic compounds in fluidized-bed reactors are regenerated by adding to the catalyst a molybdenum-enriched catalyst formed by supporting a molybdenum component which is volatile or capable of forming a volatile compound under reaction conditions on a metallic oxide catalyst. The metallic oxide catalysts contain as essential components (I) Fe, (II) Sb, (III) at least one element selected from the group consisting of V, Mo and W, and (IV) Te.
摘要:
Iron-antimony metallic oxide catalysts which have become deactivated after being used for the production of aldehydes, acids, nitriles, or dienes through oxidation, ammoxidation, or oxidative dehydrogenation of organic compounds in fluidized-bed reactors are regenerated by adding to the catalyst a solid molybdenum component which is volatile or capable of forming a volatile compound under reaction conditions. The metallic oxide catalysts contain as essential components (I) Fe, (II) Sb, (III) at least one element selected from the group consisting of V, MO, and W, and (IV) Te.
摘要:
The present invention provides a fluidized bed catalyst for the synthetic reaction of organic compounds which has a reduced catalyst loss. A fluidized bed catalyst for organic compound synthetic reaction, characterized in that 90% or more of the catalyst particles is in the range of 5-500 .mu.m on the weight-based particle size distribution and 90% or more of the 20-75 .mu.m particles has a crushing strength which satisfies the following equation:CS>A.multidot.d.sub..alpha.wherein CS represents a crushing strength �g-weight/particle!,A represents a constant 0.001,d represents a particle diameter �.mu.m!, and.alpha. represents a constant 2.
摘要:
A process for the production of antimony-containing metal oxide catalysts, comprising preparing a slurry containing as essential components an antimony component, a polyvalent metal compound, and silica sol, heating and drying the slurry to form a solid product, and then calcining the solid product, wherein the antimony component is a mixture of (A) at least one of antimonic acid, polyantimonic acid and the salts thereof and (B) antimony trioxide, and is prepared by mixing (A) and (B) in such a manner that the antimony provided by the (B) constitutes from 0.1 to 70 atomic % of the total amount of antimony and further in an aqueous slurry state. These antimony-containing metal oxide catalysts have superior activity and physical properties, and further reproducibility in the preparation thereof. Thus they are useful for production of aldehydes and acids through oxidation, nitriles through ammoxidation, and dienes, unsaturated aldehydes and unsaturated acids through oxidative dehydrogenation.
摘要:
A process for preparing an antimony/tellurium-containing metal oxide catalyst, comprising preparing a slurry containing an antimony compound, a polyvalent metal compound, and a silica support starting material selected from silica sol and mixtures of silica sol and white carbon, fumed silica or silica hydrogel, heating the slurry at a pH or 7 or less and a temperature of at least 40.degree. C., mixing the above heat treated slurry with a tellurium solution which has been independently prepared by oxidizing metallic tellurium with hydrogen peroxide in the presence of the oxide, oxyacid or oxyacid salt of at least one metal selected from the group consisting of vanadium, molybdenum and tungsten, and then drying and calcining the resulting mixture.
摘要:
A process for producing acrylonitrile by the vapor-phase catalytic ammoxidation of propylene, which comprises(I) reacting propylene, a molecular oxygen-containing gas and ammonia in the presence of a catalyst expressed by the following empirical formulaFe.sub.a Sb.sub.b Mo.sub.c Me.sub.d Te.sub.e Q.sub.f Na.sub.g O.sub.h. (SIO).sub.iwherein Me is at least one element selected from the group consisting of V and W,Q is at least one element selected from the group consisting of Cu, Mg, Zn and Ni, andthe subscripts a, b, c, d, e, f, g, h and i each represents atomic ratios such that when a=10; b=13 to 28; c=0.1 to 2.5; d=0.05 to 1; e=0.2 to 5; f=0 to 4 (in which case b=13 to 20), or f=2 to 6 (in which case b=20 to 28); g=0 to 3; h=the number of oxygens corresponding to the oxide formed by the combination of the components, and i=25 to 200;in a fluidized bed catalytic reaction zone at a temperature of about 380 to about 500.degree. C. and a pressure of about 0.2 to about 3 kg/cm.sup.2 -G while adjusting the propylene/oxygen/ammonia molar ratio to about 1:about 1:about 0.8 to about 1:about 4:about 3;(II) the catalyst being prepared by(1) intimately mixing starting materials for the Fe, Mo, Me, Te and Q components in a form soluble in water or nitric acid, a starting material for the Sb component, and silica sol which may or may not contain an Na component, thereby to form a slurry containing these components and having a non-volatile solids content of about 10 to about 50% by weight;(2) so that the composition of the final catalyst is within the range expressed by the empirical formula above;(3) spray-drying the resulting slurry, and(4) calcining the resulting spray-dried particles at a temperature of about 600 to about 950.degree. C. thereby to form a catalyst with a composition within the above empirical formula and with all of the Mo, Me, and Te components substantially dissolved in an iron/antimony oxide compound (FeSbO.sub.4) in the form of a solid solution.
摘要:
There is provided a process for producing a particulate iron-antimony containing oxide composition having high compressive strength, comprising the steps of: providing an aqueous slurry containing iron ions, nitrate ions and antimony trioxide; adjusting the slurry to a pH value in the range of 0.5 to 3 as measured at 40.degree. C.; heating the slurry; spray-drying the heated slurry; and calcining the resultant particles.