Hydrogenation of Cinnamaldehyde over Pt‐Modified Molecular Sieve Catalysts

Abstract

The catalytic properties of various Pt-modified molecular sieves were tested in liquid-phase hydrogenation of cinnamaldehyde and compared to Pt/MgO and commercial Pt/C catalysts. The type of support considerably influenced the catalytic properties. The superior selectivity performance of microporous catalysts was confirmed; the highest selectivity to allyl alcohol of about 40 % was obtained over the beta support whereas the mesoporous MCM-41-supported catalyst was unselective. The highest activity was obtained over the Pt/mordenite catalyst. In order to clarify the performance of catalysts, several characterization methods (XRD, XRF, FTIR, surface measurements) were employed.

Effect of Support Acidity on Liquid-Phase Hydrogenation of Benzene to Cyclohexene over Ru–B/ZrO2Catalysts

“…36 Murzin and co-workers found a decrease in the selectivity to unsaturated alcohol with increasing support acidity in cinnamaldehyde hydrogenation over Pt-modified molecular sieves catalysts. 42 Similar results were obtained over Ru/Al 2 O 3 catalysts, 43 inferring that the hydrogenation of the CC bond is promoted by the acid sites. Thus, it is rational to relate the selectivity patterns observed on the Ru−B/ZrO 2 -M, Ru−B/ZrO 2 -A, and Ru−B/ZrO 2 -T catalysts to the difference in the acidity of the ZrO 2 supports.…”

“…Researchers have evidenced that the product selectivity was influenced by the support acidity in many selective hydrogenation reactions. ,, Volckmar et al found that a high total amount of acid sites and a high amount of strong Lewis acid sites on the Ag/SiO 2 –Al 2 O 3 catalysts induced a low selectivity to allyl alcohol in acrolein hydrogenation . Murzin and co-workers found a decrease in the selectivity to unsaturated alcohol with increasing support acidity in cinnamaldehyde hydrogenation over Pt-modified molecular sieves catalysts . Similar results were obtained over Ru/Al 2 O 3 catalysts, inferring that the hydrogenation of the CC bond is promoted by the acid sites.…”

“…As far as the close similarity of the Ru–B nanoparticles on these Ru–B/ZrO 2 catalysts is concerned, it is reasonable to assume that the difference in the selectivity to cyclohexene is mainly determined by the ZrO 2 supports. Researchers have evidenced that the product selectivity was influenced by the support acidity in many selective hydrogenation reactions. ,, Volckmar et al found that a high total amount of acid sites and a high amount of strong Lewis acid sites on the Ag/SiO 2 –Al 2 O 3 catalysts induced a low selectivity to allyl alcohol in acrolein hydrogenation . Murzin and co-workers found a decrease in the selectivity to unsaturated alcohol with increasing support acidity in cinnamaldehyde hydrogenation over Pt-modified molecular sieves catalysts .…”

Chemoselective hydrogenation of cinnamaldehyde at atmospheric pressure over combustion synthesized Pd catalysts

“…The catalytic activity also depends on the acidity or the basicity and structural characteristics (particles size and porosity) of the support [29,30]. Different types of supported palladium catalysts such as Pd/carbon [31,32], Pd/SiO2 [33], Pd/Al2O3 [34], Pd/TiO2 [35], Pd/Fe2O3@C [36] have been reported to be efficient catalytic system for the hydrogenation of cinnamaldehyde.…”