Catalyst for producing unsaturated carboxylic acids

Abstract

A process for producing unsaturated carboxylic acids, which comprises oxidizing unsaturated aldehydes in the vapor phase in the presence of a catalyst comprising a catalytic oxide supported on an inert carrier, such catalytic oxide containing metal elements in the atomic ratio Mo:V:Cu:Cr:W of 12:2-14:1-6:0-4:0-12 with the proviso that Cr + W is not 0.

What is claimed is: 
     
       1. A catalyst adapted for the production of unsaturated carboxylic acids through the vapor phase oxidation of unsaturated aldehydes comprising a catalytic oxide supported on an inert carrier, said catalytic oxide consisting essentially of the recited metal elements in the atomic ratio Mo:V:Cu:Cr:W of 12:2-14:1-6:0-4:0-12 with the proviso that Cr + W is not O, said inert carrier having a surface area not greater than 2 m 2  /g and a porosity of 30 to 65%, at least 90% of the pores having a pore diameter in the range of 50 to 1,500 microns. 
     
     
       2. The catalyst of claim 1 wherein said inert carrier is selected from α-alumina, silicon carbide, pumice, silica, zirconia, titanium oxide and mixtures thereof. 
     
     
       3. The catalyst of claim 1 wherein said catalytic oxide consists essentially of the recited metal elements in the atomic ratio Mo:V:Cu:Cr:W of about 12:4:6:2.2:0.6:2.4. 
     
     
       4. The catalyst of claim 1 wherein said catalytic oxide consists essentially of the recited metal elements in the atomic ratio Mo:V:Cu:Cr:W of about 12:6:2.2:0:2.4. 
     
     
       5. The catalyst of claim 1 wherein said catalytic oxide consists essentially of the recited metal elements in the atomic ratio Mo:V:Cu:Cr:W of about 12:4.6:2.2.0.4:4. 
     
     
       6. The catalyst of claim 1 wherein said catalytic oxide consists essentially of the recited metal elements in the atomic ratio Mo:V:Cu:Cr:W of about 12:6:2.2:1.2:0. 
     
     
       7. The catalyst of claim 1 wherein said catalytic oxide consists essentially of the recited metal elements in the atomic ratio Mo:V:Cu:Cr:W of about 12:4.6:4.4:0.6:2.4. 
     
     
       8. The catalyst of claim 1 wherein said catalytic oxide consists essentially of the recited metal elements in the atomic ratio Mo:V:Cu:Cr:W of about 12:8:2.2:0.8:1.0.