Study On The Efficient Nickel-based Catalyst And Novel Process For Synthesis Of P-phenetidine By Catalytic Hydrogenation

P-phenetidine is an important intermediate in organic synthesis,which is mainly used to prepare the precursor of food antioxidant-ethoxyquin with broad application and high market demand.The advantages of the method to synthesize p-phenetidine via catalytic hydrogenation of 4-nitrophenetole are more selective,stable and producing less waste.But types of catalysts and catalytic conditions have significant impact on the conversion rate,selectivity,and cycling times of catalyst,which limited the application in industry.Based on literature research and the analysis of technical principle,a new method was studied on high-efficiency nickel-based catalysts and process conditions,and a new synthetic process was developed.Three modified Ni based catalysts:Ti-Ni-Al?Mo-Ni-Al?Cr-Ni-Al was studied for their conversion rate,selectivity and stability.though Mo-Ni-Al framed catalyst has good conversion rate,selectivity and stability,optimized process conditions were studied with process temperature 363K,pressure 2.0MPa,methanol,methanol:4-nitrophenetole =1:1(V/V).The result indicated that the conversion rate was nearly 100%,the selectivity was 99.3%,but the the activity decreased significantly after 15 times recycling.In order to solve the problem of recycle times and develop a better type of catalyst,a series of supported nickel-based catalysts were prepared via IWIP of SiO2?TiO2??-Al2O3,and were evaluated with BET,XRT,TPR and reactivity assessment..Among the catalysts with the different supports,the?-Al2O3 supported nickel catalyst showed the highest activity and conversion rate;With the increase of nickle content,the activity of catalyst increased,but when Ni content reached 30%w/w,the conversion rate and selectivity reached the highest threshold.With the optimized process condition was:solvent-methanol,temperature 359-368K,pressure 2.0MPa,agititation speed 800rpm,the conversion rate was nearly 100%,selectivity was 99.2%,and the catalyst reactivity did not decreased significantly after recycled 35 times.After industrial production study,the production data was consistent with the bench scale result.And in production,water usage was not maore than 10%of solvent quantity,loading index was lower than 80%.The reactivity of catalyst did not decreased significantly with catalyst recycling.The study result supplied data for further scaling-up production and a series of feasible process conditions were supplied.