An Effective Pt-Cu/SiO₂ Catalyst for the Selective Hydrogenation of Cinnamaldehyde

Table 3

Catalytic activities of Pt-Cu/SiO catalysts for the hydrogenation of CAL.

Sample	Con. (%)	TOF (h^−1)	Sel. (mol%)
			COL	HALD	HALC	Others
SiO2	5.8	-	0	0.9	1.5	97.6
Cu/SiO2	10.2	-	1.4	5.9	6.3	86.4
Pt/SiO2	38.3	329	3.7	1.3	35.4	59.6
Pt-Cu/SiO2	37.9	3076	64.1	5.4	11.3	19.2

Reaction conditions: 50 mg catalyst, 1.00 g CAL, 30 mL isopropanol, 10 bar H₂, 80°C, 2 h. Turnover frequency (TOF) = [moles of cinnamyl alcohol formed]/[(moles of Pt loading) × (reaction time) × D(Pt)] [27]. Including possibly 1-(3-propoxyprop-1-enyl)benzene, cinnamyl formate, cinnamic acid, benzyl cinnamate, 4,4-diphenylcyclohexane-1,5-dienyl acetate, and other condensation products that could be identified by GC-MS because of their large molecular weights.