Activating molybdenum-contg. mixed oxide catalyst for propene ammoxidation - by treating with readily-dispersed bismuth-III cpd. at 300-600 deg.C

摘要

Activating molybdenum-contg. mixed oxide catalysts which can contain other metal ions such as Cr, Bi, Fe, Co, Na or Si (I), and which are used for the gas-phase ammoxidation of propene to acrylonitrile (AN) at 350-500 deg.C and 30-200 kPa in a fluidised bed comprises adding 1 pt. wt. of a Bi(III) cpd. (II) which is readily dispersible in the gas phase at 350-500 deg.C to 10-100 pts. wt. ammonia-treated catalyst (I) at 300-600 deg.C and allowing it to react for 5 mins.-2 hrs. USE/ADVANTAGE - The process enables exhausted or badly produced catayst (I) to be regenerated or activated without removing it from the ammoxidation unit; the reactivated (I) has selectivity above 82% w.r.t. AN