Study On The Catalytic Amination Reaction Of Sorbitol To Nitriles

In the context of the shortage of global fossil resources,the development of fuels and basic chemicals through catalytic conversion with renewable biomass resources has become a trend.In this paper,the biomass-derived sorbitol has been converted to acetonitrile and propionitrile through catalytic amination method.It provides a new research to convert sorbitol to value-added chemicals.A series of metal oxide catalysts were prepared by kneading extruding method and were tested in a fixed-bed reactor for the amination of sorbitol to nitriles.Fe₁₅/?-Al₂O₃catalyst showed the highest activity among all the catalysts.Acetonitrile and propionitrile as major products were obtained over this catalyst,meanwhile,pyridine,ethylene as well as propylene as by-products were also received.The parameters affecting the performance of the catalyst Fe₁₅/?-Al₂O₃ were investigated carefully.When the reaction was conducted under the optimized parameters,being a temperature of 510 ^oC,atmospheric pressure with a molar ratio of ammonia to sorbitol of 14:1 and GHSV of 982 h^-1,the total carbon yield of C₂ and C₃ nitriles reached40.1%.The catalyst was characterized by XRD,N₂ adsorption measurement,TEM,XPS and IR of the adsorbed pyridine.Characterization results revealed that the doping of suitable amount of iron into?-Al₂O₃ can create Br?nsted acid centers in the catalyst,which can accelerate the condensation of aldehydes with ammonia to generate imines and are beneficial to the selective conversion of sorbitol to acetonitrile and propionitrile.The doped iron exists in the form of Fe₂O₃ nanoparticles with diameters of 5–7 nm observed from TEM images.The Fe₂O₃ nanoparticles act as dehydrogenation-hydrogenation active species in the catalytic conversion of sorbitol with ammonia.