Process for the manufacture of unsaturated aldehydes and acids from the corresponding olefins

Abstract

A process for the catalytic oxidation of olefins to unsaturated aldehydes and acids and the ammoxidation of olefins to unsaturated nitriles in which the catalyst comprises a promoted, reduced, antimony oxidemolybdenum oxide-containing catalyst.

We claim: 
     
       1. A process for the oxidation of propylene and isobutylene to form the corresponding unsaturated aldehydes and unsaturated acids comprising contacting in the vapor phase at a temperature within the range of from about 250° to about 600° C. a mixture of a molecular oxygen-containing gas and either propylene or isobutylene, or mixtures thereof, in a molar ratio of oxygen to olefin within the range from about 0.5 to 10, in the presence of a promoted, reduced, antimony oxide-molybdenum oxide-containing catalyst wherein the catalyst is prepared by combining the following components in any order: a. an aqueous slurry of molybdenum trioxide;   b. a reducing agent selected from the group consisting of finely divided metal, sulfur, sulfur dioxide, hydrogen sulfide, hydrazine, hydrate, ammonia, hydroxylamine and an organic reducing agent capable of reducing at least some of the molybdenum to a valence state below +6 in a ratio of from about 0.0001 to 0.2 moles of the reducing agent per mole of molybdenum;   c. antimony oxide in a ratio of from about 0.1 to 9 moles of antimony oxide per mole of molybdenum; and   d. at least one promoter element in the form of a non-oxidizing compound selected from the group consisting of tellurium, tungsten, titanium, manganese, nickel, iron, copper, lead, rhenium, bismuth, tin, uranium, chromium, phosphorus and boron, said promoter element being added in a ratio of from about 0.0001 to 10 moles of promoter element per mole of molybdenum.   
     
     
       2. The process in claim 1 wherein the finely divided metal in component (b) in the catalyst preparation is selected from the group consisting of molybdenum, tungsten, aluminum and nickel. 
     
     
       3. The process in claim 2 wherein the catalyst components are combined in the following order: a. molybdenum trioxide is reacted with the reducing agent;   b. antimony trioxide is added to the reaction mixture of (a); and   c. the promoter element in the form of a non-oxidizing compound is subsequently added to the reaction mixture of (b). .Iadd. 4. A process for the production of methacrylic acid by the oxidation of methacrolein with molecular oxygen in the vapor phase at a reaction temperature of about 200° C. to about 500° C. in the presence of a promoted, reduced, antimony oxide-molybdenum oxide containing catalyst wherein the catalyst is prepared by combining the following components in any order:   a. an aqueous slurry of molybdenum trioxide;   b. a reducing agent selected from the group consisting of a finely divided metal, sulfur, sulfur dioxide, hydrogen sulfide, hydrazine hydrate, ammonia, hydroxylamine, and an organic reducing agent capable of reducing at least some of the molybdenum to a valence state below +6 in a ratio of from about 0.0001 to 0.2 mole of the reducing per mole of molybdenum;   c. antimony oxide in a ratio of from about 0.01 to 9 moles of antimony oxide per mole of molybdenum; and   d. at least one promoter element in the form of a non-oxidizing compound selected from the group consisting of tellurium, tungsten, titanium, manganese, nickel, iron, cobalt, lead, rhenium, bismuth, tin, uranium, chromium, phosphorus and boron, said promoter element being added in a ratio of from about 0.0001 to 1.0 moles of promoter element per mole of molybdenum. .Iaddend..Iadd. 5. The process of claim 4 wherein the finely divided metal in component (b) in the catalyst preparation is selected from the group consisting of molybdenum, tungsten, aluminum and nickel. .Iaddend. .Iadd. 6. The process of claim 5 wherein the promoter element is phosphorus. .Iaddend..Iadd. 7. The process of claim 6 wherein catalyst is of the formula P 0 .01 [Sb 2  Mo 3  O x  +Mo° 0 .06 ]. .Iaddend..Iadd. 8. The process of claim 5 wherein the finely divided metal in component (b) in the catalyst preparation is molybdenum. .Iaddend..Iadd. 9. The process of claim 5 wherein the catalyst components are combined in the following order:   a. molybdenum trioxide is reacted with a reducing agent;   b. antimony trioxide is added to the reaction mixture of (a); and   c. the promoter element in the form of a non-oxidizing compound is subsequently added to the reaction mixture of (b). .Iaddend..Iadd. 10. A process for the production of methacrylic acid by the oxidation of methacrolein with molecular oxygen in the vapor phase at a reaction temperature of about 200° C. to about 500° C. in the presence of a reduced, antimony oxide-molybdenum oxide containing catalyst wherein the catalyst is prepared by combining the following components in any order:   a. an aqueous slurry of molybdenum trioxide;   b. a reducing agent selected from the group consisting of a finely divided metal, sulfur, sulfur dioxide, hydrogen sulfide, hydrazine hydrate, ammonia, hydroxylamine and an organic reducing agent capable of reducing at least some of the molybdenum to a valence state below +6 at ratio of from about 0.0001 to 0.2 moles of the reducing agent per mole of molybdenum; and   c. antimony oxide in a ratio of from about 0.1 to 9 moles of antimony oxide   
     
     
        promoted molybdenum. .Iaddend..Iadd. 11.  The process of claim 10 wherein the finely divided metal in component (b) in the catalyst preparation is selected from the group consisting of molybdenum, tungsten, aluminum and nickel. .Iaddend..Iadd. 12. The process of claim 11 wherein the finely divided metal in component (b) in the catalyst preparation is molybdenum. .Iaddend..Iadd. 13. The process of claim 11 wherein the catalyst is of the formula [Sb 2  Mo 3  O x  +Mo° 0 .06 ]. .Iaddend. .Iadd. 14. The process of claim 11 wherein the catalyst components are combined in the following order: a. molybdenum trioxide is reacted with the reducing agent; and   b. antimony trioxide is added to the reaction mixture of (a). .Iaddend.