2. Operating principles of mild oxidation catalysts

2.1 Key features

Catalysts for mild oxidation are oxides and oxysalts (phosphates, sulfates) of transition metals from the first columns of the periodic table (V, Nb, Mo, W, etc.). These crystallized oxide catalysts are naturally polyfunctional. They exhibit the acidic (Lewis and Brønsted O—H), electronic (semiconductivity) and redox properties required in any oxidation reaction. The Me ⁿ⁺ cations most active in controlled oxidation are V ⁵⁺ and Mo ⁶⁺ , which subsequently reduce and reoxidize very readily. As the cation is reducible, it is the properties of the Me ⁿ⁺ —O ^2– ...