CATALYST SYSTEM FOR CATALYTIC GAS PHASE REACTIONS FEATURING AN INCREASING CATALYST ACTIVITY IN THE DIRECTION OF FLOW OF THE GAS

摘要

The invention relates to catalyst systems for catalytic gas phase reactions which are characterized in that the catalyst activity increases in the direction of flow of the gas, the catalyst activity being controlled using mixtures of low activity and high activity catalysts. The invention further relates to methods for producing phthalic anhydride, ethylene dichloride, cyclohexanone, maleic anhydride, and acrylic acid.