Bimetallic Pt-Co catalysis on carbon nanotubes for the selective hydrogenation of cinnamaldehyde to cinnamyl alcohol: Preparation and characterization

• Published in: Journal of molecular catalysis. A, Chemical Vol. 279; no. 1; pp. 140 - 146
• Main Authors: Li, Yan, Li, Zhen-Guo, Zhou, Ren-Xian
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 02.01.2008; Elsevier
• Subjects: Catalysis; Chemistry; Cinnamaldehyde (CMA); Cinnamyl alcohol (CMO); Exact sciences and technology; General and physical chemistry; Pt-Co/CNTs catalyst; Selective hydrogenation; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Cinnamaldehyde (CMA); Selective hydrogenation; Cinnamyl alcohol (CMO); Pt-Co/CNTs catalyst; Mixed catalyst; Catalytic reaction; Carbon nanotubes; Enaldehyde; Cobalt; Hydrogenation; Supported catalyst; Characterization; Heterogeneous catalysis; Platinum; Preparation; Benzenic compound; Catalysis; Catalyst
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/j.molcata.2007.10.015

H 2-TPR profiles of the CNTs supported Pt-Co catalysts are shown in Fig. 2. The Pt-Co/CNTs (I) catalyst presents a large peak of H 2 consumption appearing at a higher temperature, 250 °C. The high consumption of H 2 (H 2/Pt = 3 .3) is in accordance with that already observed and can be interpreted by the following equation: ⌈Pt(OH) 4(Cl) 2⌋ 2− + 3H 2 → Pt 0 + 4H 2O + 2HCl + 2 e− .The other catalysts present a reduction maximum at about 20 °C, with a H 2/Pt ratio basically equal to 2. ▪ Carbon nanotubes (CNTs)-based Pt-Co catalysts are prepared by different impregnation techniques and different reduction methods (H 2, HCHO and KBH 4) for the selective reduction of cinnamaldehyde (CMA) to the corresponding cinnamyl alcohol (CMO). The selectivity and activity of the Pt-Co/CNTs catalysts can be improved significantly by using ammonia as a ligand and KBH 4 as a reducing agent because of the synergetic effect of Pt-Co-B. Furthermore, the hydrogenation rate of CMA increases ulteriorly in the presence of trace base and acid promoters.