| abstract |
Methacrolein is catalytically oxidized into methacrylic acid in the vapor phase at a temperature of 200 DEG to 450 DEG C. The catalyst used is comprised of molybdenum, phosphorus, potassium and/or cesium, vanadium, silver and/or tellurium, and oxygen, and represented by the formula: Mo12PaAbVcXdOe wherein A is K and/or Cs and X is Ag and/or Te, and a=0.5-5, b=0.1-4, c=0.05-3, d=0.001-2 and e is a positive number required by the valence states of the other elements present. |