Applied Catalysis A: General, Vol.568, 76-85, 2018
Supported TiO2/MCM-41 as an efficient and eco-friendly catalyst for highly selective preparation of cyclohexanone oxime from solvent-free liquid phase oxidation of cyclohexylamine with molecular oxygen
A green and efficient approach for solvent-free selective catalytic oxidation of cyclohexylamine to cyclohexanone oxime in liquid phase has been developed. The results showed that the supported 30%TiO2/MCM-41 as efficient and eco-friendly catalyst gave 78.4% of cyclohexylamine conversion with 89.1% of selectivity to cyclohexanone oxime. It has been demonstrated that the catalytic active sites are the surface titanium hydroxyl groups of catalyst. Moreover, the present catalyst can be easily separated, recycled, regenerated and reused. The probable catalytic reaction mechanism of cyclohexylamine with molecular oxygen over supported TiO2/MCM-41 was suggested. This work affords a new and environmentally friendly route for the synthesis of cyclohexanone oxime, and has important industrial application prospects.
Keywords:Supported TiO2/MCM-41;Cyclohexylamine;Cyclohexanone oxime;Molecular oxygen;Solvent-free;Liquid phase catalytic oxidation