A new method has been presented for the preparation of catalysts for selective hydrogenation of cinnamaldehyde to cinnamyl alcohol (compound used in the synthesis of drugs and flagrances). The following steps have been included in the catalysts preparation procedure: a. reaction of the support (g-Al₂O₃, TiO₂, SiO₂, MgO) with transition metal alkoxide (Zr(OBu)₄, Ti(OBu)₄, (BuO)₃VO); b. thermal decomposition of the obtained surface complex; c. dry impregnation with an aqueous solution of Pt and Fe salts; d. drying; e. reduction with gaseous hydrogen. The products of each step were characterized by means of AAS, XRD, FTIR-PAS, SEM, SIMS and TPR. The monolayer of transition metal oxide (TMOM) (ZrO₂, TiO₂ or V₂O₅) has been formed on the surface of support as a result of surface complex decomposition (b.) at 623 K. Small crystallites (<10 nm) of these oxides have been observed after the decomposition of mentioned complex at 823 K. Ferroane phase (PtFe) has been detected among others on the surface of reduced Pt-Fe catalysts.

A hydrogenation of cinnamyl aldehyde was performed in the flow system (T = 423–573 K, p = 1 atm). The catalyst’s selectivity in cinnamyl alcohol synthesis increased in the following order: Pt/support << Pt-Fe/support < Pt/TMOM/support < Pt-Fe/TMOM/support. In the optimized reaction conditions hydrogenation of cinnamaldehyde over Pt-Fe/ZrO₂/MgO yielded cinnamyl alcohol as a main product (78%, selectivity over 90 %).

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/8760 must be provided.

1. Selective hydrogenation of isophorone in the presence of catalysts containing nanostructured metals
2. Prolonged ageing polymers modified by plasma carbon black