Preparation of maleic anhydrides and catalysts thereof

Claim 1

IN THE VAPOR PHASE CATALYTIC PARTIAL OXIDATION PROCESS FOR THE MANUFACTURE OF A DICARBOXYLIC ACID ANHYDRIDE FROM THE GROUP CONSISTING OF MALEIC ANHYDRIDE AND METHYL MALEIC ANHYDRIDE, THE IMPROVEMENT COMPRISING CONDUCTING THE OXIDATION IN CONTACT WITH A CATALYST COMPRISING SOLID INERT CARRIER PARTICLES HAVING AN ADHERENT COATING OF SOLID INERT CARRIER PARTICLES HAVING AN ADHERENT COATING OF AN INTIMATE MIXTURE OF VANADIUM PENTOXIDE AND MOLYBDENUM TRIOXIDE THEREON PRODUCED BY COATING SAID AN INTIMATE MIXTURE OF VANADIUM PENTOXIDE AND MOLYBDENUM TRIOXIDE BY CONTACTING THE CARRIER PARTICLES WITH AN AQUEOUS SOLUTION CONTAINING COLLOIDAL VANADIUM PENTOXIDE AND COLLOIDAL MOLYBDENUM TRIOXIDE PREPARED BY FUSING A MIXTURE OF V2O5 AND M0O3 WHEREIN THE RATIO OF V2O5 TO M0O3 IS FROM 10:1 TO 1:1, POURING SAID FUSED MIXTURE INTO WATER AGITATION TO PREPARE SAID AQUEOUS COLLOIDAL SOLUTION AND EVAPORATING THE WATER FROM THE COLLOIDAL SOLUTION WHILE IN CONTACT WITH THE CARRIER PARTICLES.