Regeneration of the Oxidation Catalysts Based on the Aqueous Solutions of Non-Keggin Mo-V-P Heteropoly Acids by Molecular Oxygen

ABSTRACT Kinetic peculiarities of regeneration of the aqueous solutions of non‐Keggin‐type Mo‐V‐P heteropoly acids HaPzMoyVx′Ob (HPA‐x′) and their acidic salts by O2 are studied. The HPA‐x′ solutions have heightened thermal stability that permits to consider them as highly efficient catalysts for different oxidation processes. In the HPA‐x′ and their salts solutions, these peculiarities prove to be similar. The studied reaction is of the first order with respect to O2 and V(IV), if [V(IV)] is higher than 0.8 M. As [V(IV)] decreases during the reaction, its order with respect to V(IV) increases to the third. The apparent activation energy of the reaction at temperatures 150–170°С is 37.5 kJ mol−1. The obtained kinetic equation was used to calculate a new effective air reactor for the regeneration of the homogeneous HPA‐x′ catalyst in a pilot process of methylethylketone synthesis.