Structural and catalytic properties of V-SBA-15 for the vapor phase oxidation of diphenylmethane

• Published in: Reaction kinetics, mechanisms and catalysis Vol. 104; no. 2; pp. 399 - 415
• Main Authors: Santhanaraj, D., Suresh, C., Gurulakshmi, M., Sasirekha, N. R., Shanthi, K.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-12-2011
• Subjects: Catalysis; Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Physical Chemistry; Diphenylmethane; Vapor phase oxidation; Direct hydrothermal; V-SBA-15
• ISSN: 1878-5190; 1878-5204
• DOI: 10.1007/s11144-011-0373-5

The influence of Si/V ratio of mesoporous V-SBA-15 on the structure and catalytic behavior has been investigated for the vapor phase oxidation of diphenylmethane (DPM) to benzophenone (BP) using CO
2
free air as oxidant under atmospheric pressure. The reaction conditions were optimized for a maximum conversion of DPM and selectivity for BP on V-SBA-15 (25). These catalysts were synthesized with different Si/V ratios of 10, 25, 50, 75 and 100 by the direct hydrothermal method under mild acidic conditions and characterized by using X-ray diffraction, ICP-OES, EDAX, DRUV–Vis, photoluminescence and transmission electron microscopy techniques. It was found that a large amount of vanadium is incorporated mainly in isolated tetrahedral environment with a terminal V=O bond. Under the optimized conditions, the activity of all the catalysts were compared and found that V-SBA-15 with Si/V = 25 ratio, exhibited the maximum activity. The difference in the catalytic activity is related to their physico-chemical properties.