Role of potassium in the aerobic oxidation of aromatic alcohols over K+-promoted Mn/C catalysts

The aerobic oxidation of aromatic alcohol on alkali metal promoted Mn/C catalysts has been investigated. A dramatic improvement of the oxidation activity can be observed when the Mn/C catalyst is modified with potassium ions. Characterizations of Raman and X-ray absorption fine structure (XAFS) evidence that potassium ions induce a large local distortion to Mn-O octahedrons in supported manganese oxides with coexistence of Mn2+ and Mn3+, which has been suggested to be a vital factor to enhance the activation Of 02 for the oxidation of benzylic alcohol. (C) 2008 Elsevier B.V. All rights reserved.