Study On Hydrodeoxygenation Process Of 2,5-dicyanofuran

Adiponitrile is an important raw material for the production of adipic diamine,which is a high value and important chemical product.Adipic diamine is mainly used in the raw materials of nylon 66 and high-end polyurethane.With the development of economy,people’s demand for it is increasing day by day.Currently,there is no relevant route to produce the chemical product in China,which is under the awkward situation of being controlled by others.In this study,a new method was proposed for synethsis of adiponitrile.The preparation of raw materials and its hydrogenation-deoxidation process were carried out.Moreover,the thermodynamic analysis of the reaction process,the design,preparation and characterization of catalysts,and the optimization of reaction conditions were mainly explored.The main conclusions are as follows.Firstly,the thermodynamic analysis of the target reaction process is carried out.The relationship between reaction heat,reaction standard gibbs free energy,reaction equilibrium constant and reaction temperature were analyzed.The hydrodeoxidation of raw materials is an exothermic reaction in thermodynamics,the heat released from the hydrogenation reaction is close to 400 KJ/mol,the heat released from the deoxidation reaction is 150 KJ/mol,the equilibrium constant of both reactions is more than 10,the reactions can proceed spontaneously.Ionic liquid can be used as catalyst and co-solvent for the preparation of 2,5-dicyanofuran via the reaction of ionic liquid hydroxylamine salt and 2,5-furandiformaldehyde（DFF）.The suitable reaction condition was 120℃for 2h.The solvent was 8ml paraxylene,4ml ionic liquid,and the molar ratio of ionic liquid hydroxylamine salt to 2,5-furandiformaldehyde（DFF）was 1:1.5.The yield of 2,5-dicyanofuran was 78%.The hydrogenation reaction of 2,5-dichocyanofuran was carried out with a Pd-based catalyst,supported on SiO₂and Al₂O₃carrier with a loading of 3%.Ethanol（15ml）was used as the solvent.The catalyst was 0.12g,the hydrogen pressure was4MPa,and the raw material was 0.28g.The catalyst can be reused for more than three times,and the catalytic activity is almost unchanged.The catalysts were characterized by infrared ray,XRD,scanning electron microscope and transmission electron microscope,etc.It was proved that the ionic liquid had good stability,and still had good reaction performance after repetition.The catalyst Pd/SiO₂not only had the same load as the theoretical value,but also the metal Pd was completely reduced and existed in the zero-valent state with good catalytic performance.