Direct synthesis of Mn-Ti-SBA-15 catalyst for the oxidation of ethylbenzene

• Published in: Catalysis science & technology 2013-01, Vol.3 (9), p.234-2348
• Main Authors: Visuvamithiran, P, Shanthi, K, Palanichamy, M, Murugesan, V
• Format: Article
• Language: English
• Subjects: Catalysts; Catalytic activity; Ethylbenzene; Manganese; Oxidants; Oxidation; Titanium; X-ray photoelectron spectroscopy
• ISSN: 2044-4753; 2044-4761
• DOI: 10.1039/c3cy00306j

Bimetallic Mn-Ti-SBA-15 materials were prepared by direct hydrothermal method with appropriate pH adjustment. The materials were characterized by low and wide angle XRD, N 2 sorption studies, DRSUV-Vis, XPS, ESR, SEM and TEM. The XRD and BET results clearly demonstrated the incorporation of manganese and titanium species in the SBA-15 framework without affecting the mesoscopic nature of the material. The oxidation state and coordination environment of the active sites were confirmed by DRSUV-Vis, XPS and ESR. The results revealed that Mn 2+ is in octahedral geometry whereas Mn 3+ and Ti 4+ are in tetrahedral coordination in the SBA-15 framework. The O1s XPS spectrum well established the framework incorporation of manganese and titanium species. The catalytic activity of Mn-Ti-SBA-15 materials was evaluated in the oxidation of ethylbenzene with TBHP as the oxidant under optimized reaction condition. It was found that Mn-Ti-SBA-15(50) catalyst showed high catalytic activity with a rate constant of 7.155 × 10 −3 min −1 . The synergetic effect of Mn 2+ /Mn 3+ and Ti 4+ sites in Mn-Ti-SBA-15 is a promising catalyst for the oxidation of ethylbenzene and other alkylbenzenes. Bimetallic Mn-Ti-SBA-15 materials were prepared by direct hydrothermal method with appropriate pH adjustment.