Effects of Mn addition on dehydrogenation of methylcyclohexane over Pt/Al2O3 catalyst

• Published in: Applied catalysis. A, General General, 2017-08, Vol.543, p.75-81
• Main Authors: Nakano, Atsushi, Manabe, Shota, Higo, Takuma, Seki, Hirofumi, Nagatake, Satoshi, Yabe, Tomohiro, Ogo, Shuhei, Nagatsuka, Tomomi, Sugiura, Yukihiro, Iki, Hideshi, Sekine, Yasushi
• Format: Article
• Language: English
• Subjects: Dehydrogenation of methylcyclohexane; Methane formation; Mn addition; Organic hydride; Unsaturated coordination of Pt
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2017.06.017

[Display omitted] •The effect of adding Mn to Pt/Al2O3 on the selectivity of dehydrogenation for MCH was investigated.•Pt-Mn/Al2O3 shows higher selectivity for dehydrogenation than Pt/Al2O3 while keeping high activity.•Although Pt and Mn do not form an alloy, the unsaturated coordination of Pt decreased by adding Mn.•The unsaturated coordination of Pt promotes toluene decomposition, and adjacent Mn suppressed it. Methylcyclohexane (MCH) is a prospective hydrogen carrier candidate. Although Pt/Al2O3 catalyst shows high conversion for dehydrogenation of MCH at 623K, methane formation and deactivation caused by coke deposition are issues over the catalyst. Results of this study demonstrate that Mn addition to Pt/Al2O3 brought higher selectivity and stability for dehydrogenation of MCH than with Pt/Al2O3 alone. Although Pt and Mn do not form an alloy structure, Pt and Mn form an adjacent structure, and the unsaturated coordination of Pt which promotes methane formation and deactivation decreased. Pt-Mn/Al2O3 shows high catalytic performance by virtue of the coverage of such sites by MnOx.