Issue 14, 2018

Solvent effects on heterogeneous catalysis in the selective hydrogenation of cinnamaldehyde over a conventional Pd/C catalyst

Abstract

Solvent effects in the selective hydrogenation of an α,β-unsaturated aldehyde of cinnamaldehyde (CAL) were investigated under gas–liquid–solid reaction conditions. A conventional 5 wt% Pd/C catalyst and twelve organic solvents were used, including apolar solvents (three) and protic (two) and aprotic (seven) polar ones. The total rate of CAL hydrogenation strongly depended on the solvents used. The relationship between the rate of CAL hydrogenation observed and a few different solvent parameters was examined. The main product was hydrocinnamaldehyde (HCAL) with a selectivity of 80% or higher in most of the solvents examined except for pyridine and 4-methylpyridine. In these two solvents, the CAL hydrogenation was slow and the main product was changed to cinnamyl alcohol (COL) with a selectivity of about 60%. The addition of a small volume of pyridine to other solvents such as 2-propanol and tetrahydrofuran could change the rate of hydrogenation and switch the main product from HCAL to COL. Possible interactions among the solvents, CAL substrate, and Pd/C catalyst were examined by FTIR (attenuated total reflection (ATR-) and diffuse reflectance modes (DR-)) and TPD to discuss the solvent effects observed in the Pd-catalyzed heterogeneous CAL hydrogenation.

Graphical abstract: Solvent effects on heterogeneous catalysis in the selective hydrogenation of cinnamaldehyde over a conventional Pd/C catalyst

Supplementary files

Article information

Article type
Paper
Submitted
10 May 2018
Accepted
21 Jun 2018
First published
21 Jun 2018

Catal. Sci. Technol., 2018,8, 3580-3589

Solvent effects on heterogeneous catalysis in the selective hydrogenation of cinnamaldehyde over a conventional Pd/C catalyst

Y. Li, H. Cheng, W. Lin, C. Zhang, Q. Wu, F. Zhao and M. Arai, Catal. Sci. Technol., 2018, 8, 3580 DOI: 10.1039/C8CY00943K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements