Selective Hydrogenation Of Cinnamaldehyde And Levulinic Acid

In the first part, graphene, a new2D carbon material, was selected as the support for selective hydrogenation of cinnamaldehyde to cinnamyl alcohol. Through BET, XRD, XPS and TEM characterizations, it was found that graphene with larger surface area and less surface oxygenic functional groups made metal particles more uniform than other carbon materials, so it had potential to be a good catalyst support. After optimizing the preparation method, NaBH4was selected as a better reducing agent which made the preparation easier and the catalyst performed higher selectivity. At the condition of40℃,2MPa,10ml isopropanol and reacted for3h, cinnamaldehyde could be conversed91.8%, and the selectivity for cinnamyl alcohol was87.1%. Pt-Co bimetal catalyst with the mass ratio5:1was selected by investigating the metal additives and its ratio. At the same condition, cinnamaldehyde could be conversed94.6%, and the selectivity for cinnamyl alcohol was89.6%. HRTEM showed that Pt-Co bimetal formed a hollow structure in the surface of graphene which not only enlarged the availability of Pt nanoparticles but also increased the availability of Pt atoms and finally improved the catalytic activity.In the second part, rapid quenching Raney Ni catalyst was used for hydrogenation of levulinic acid to y-valerolactone. It’s found that rapid quenching Raney Ni performed better catalytic activity and selectivity than other skeleton type metal catalysts. By recycling tests and ICP detection, isopropanol was selected as the best solvent because it could efficiently restrain the metal loss. After optimization the reaction conditions,97.4%yield of γ-valerolactone could be achieved in100℃,1.5MPa. Compared with commercial used Raney Ni, rapid quenching Raney Ni was more stable after recycling tests. XRD, BET and SEM characterizations showed that rapid quenching Raney Ni had larger surface area and rougher surface which meant more active site.