Selective Synthesis of Hydrocinnamaldehyde over Bimetallic Ni-Cu Nanocatalyst Supported on Graphene Oxide

Hydrogenation of cinnamaldehyde yields hydrocinnamaldehyde, cinnamyl alcohol, and hydrocinnamyl alcohol, all having important applications in different industries. The selective synthesis of hydrocinnamaldehyde, which is a perfumery compound, from cinnamaldehyde is challenging. In the current work, bimetallic nanocatalyst Ni-Cu supported on reduced graphene oxide (RGO) was prepared via the solvothermal method. Different combinations of Ni-Cu@RGO were used for the hydrogenation of cinnamaldehyde in methanol as a solvent at 20 bar and 150 degrees C. Ni-Cu ratio was altered to understand its influence on the selectivity of the desired product hydrocinnamaldehyde. Hydrogenation of C=C bond over the C=O bond was favored over 5% Ni-Cu@RGO catalyst in the optimized ratio of Ni:Cu (1:1). Optimization of process parameters and characterization of fresh and reused catalyst was performed. The Langmuir-Hinshelwood-Hougen-Watson model was used to fit the reaction data. The catalyst is robust and reusable, and the process is green.