Process for the manufacture of unsaturated nitriles

Claim 1

IN A ONE-STAGE PROCESS FOR THE MANUFACTURE OF A COMPOUND SELECTED FROM THE GROUP CONSISTING OF ACRYLONITRILE AND METHACRYLONITRILE BY REACTING AN OLEFIN SELECTED FROM THE GROUP CONSISTING OF PROPYLNE AND ISOBUTYLENE, RESPECTIVELY, WITH AT LEAST ONE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF AIR AND OXYGEN IN THE PRESENCE OF AMMONIA, THE RATIO BY VOLUME OF OLEFIN:AMMONIA:AIR BEING WITHIN THE RANGE OF ABOUT 1:1:7.5 TO 1:1.2:10 AT A TEMPERATURE OF ABOUT 300 TO 600*C., UNDER A PRESSURE OF ABOUT 0.1 TO 10 ATMOSPHERES ABSOLUTE AND WITHIN A PERIOD OF TIME OF ABOUT 0.05 TO 50 SECONDS ON A CATALYST APPLIED TO A CARRIER, THE IMPROVEMENT WHICH CONSISTS IN CARRYING OUT THE REACTION IN CONTACT WITH THE SAID CATALYST CONSISTING ESSENTIALLY OF ABOUT 4.5 TO 10 GRAM ATOMS TIN IN THE FORM OF SNO2 PER GRAM ATOM VANADIUM IN THE FORM OF V2O5, AND ABOUT 50 TO 90% BY WEIGHT OF A CARRIER MATERIAL SELECTED FROM SILICIC ACID AND ALUMINUM PHOSPHATE, THE CATALYST HAVING BEEN CALCINED AT A TEMPERATURE OF ABOUT 400 TO 800*C.