Catalytic ability of plasma heat-treated metal oxides on vapor-phase Beckmann rearrangement

Abstract The vapor-phase Beckmann rearrangement of cyclohexanone oxime for e -caprolactam catalyzed by various metal oxide powders was studied by using a flow reactor system. It was shown that there is a correlation between the e -caprolactam selectivity and electronegativity of the catalysts. The most effective catalyst for this reaction was niobium oxide, which was prepared by the microwave cold plasma heating method. This means that the surface characteristics of metal oxides prepared by the plasma heating are different from those prepared by the electric furnace heating method.