Study On The Process And Dynamics Of Catalytic Hydrogenation Of Adiponitrile Preparate Hexanediamine

Hexanediamine is a kind of important chemical raw material, mainly for producing nylon 66 reaction with adipic acid, and for producing nylon 610 reaction with sebacic acid. Recently, with the progress of technology and the development of novel chemical materials, hexanediamine also can be used to produce polyimide acid ester foams, coatings, adhesives, rubber chemicals and bleach, etc. And it has been more and more widely used.In the process of catalytic hydrogenation of adiponitrile to hexanediamine, ethanol was taken as solvent and Raney Ni as catalyst. Uniform experiments and single-factor experiments were designed to research the effect of reaction time,reaction temperature,hydrogen pressure, catalyst amount and stirring rate on adiponitrile hydrogenation reaction. The results showed that when the amount of adiponitrile was 144 grams, and the same volume of absolute ethylalcohol were used as solvent, the temperature was 75℃, reaction time was 8 hours, the ratio of catalyst mass was 6.6% of adiponitrile mass, hydrogen pressure was 3.3Mpa and stirring rate was 500r·min-1, the percent conversion reached 100% and the yield was more than 96%.The reaction kinetics of catalytic hydrogenation of adiponitrile on Raney-Ni catalyst had been studied in a high-pressure batch reactor. Under the condition of no inside and outside diffusion, the concentration of adiponitrile, aminocaproic nitrile and hexanediamine versus time over the Raney-Ni catalyst were measured. The kinetic parameters of catalytic hydrogenation of adiponitrile to hexanediamine such as reaction order, rate constant and activated energy in each step were obtained.The results show that in the condition of eliminating the influence of inner and outer diffuse, the catalytic hydrogenation of adiponitrile is the level 1 when the temperature is 328K to 358K and the pressure is 2-3.5MPa. As to hydrogen pressure is 1.4 level reaction; while Hexamethylene diamine formed by continuing to aid hydrogen to the interim production aminocaproicnitrile, the reaction is 0 level to aminocaproicnitrile and 1.3 level to hydrogen pressure. Dynamics function of catalyzing adiponitrile could be got by fitting the dynamics parameter which gives a solid theory basement to understand the reaction.In this dissertation, laser monitoring device was used, poikilothermic dissolution method was adopted to determine the solubility of hexanediamine in methanol-water and ethylene glycol-water system. The temperature range of this experiment is form 5℃to 35℃, Water range of the mixed solvent is from 10% to 30%. The results showed that hexanediamine's solubility increased with the temperature increasing in different systems, hexanediamine's solubility increased with the increasing of water content at the same temperature. And the experimental results were correlated by using simplified Parameter equation, the calculated results and the experimental data were in good correspondence. Solubility data obtained in this study can supply reference for the separation and purification of the crude products.