Study On Green Continuous Process Of β-Aminopropionitrile

D-calcium pantothenate is one of the thirteen essential vitamins of human body. It has been applicated extensively in the feed industry except as a drug and health food additive outside. And domestic and international market demand is under the growth rate of11%-12%year by year. So D-calcium pantothenate has good economic efficiency and vast development prospects. P-Alanine is an important intermediate of D-calcium pantothenate. The synthesis technology of β-alanine has many reports at home and abroad, but there are some defects such as low yield, difficult separation of products, many side reactions, especially the synthesis of β-aminopropionitrile. Therefore, the technical study on green continuous process of preparation of β-aminopropionitrile is significant meaningful for realizing industrialization continuous process of that.This dissertation mainly focuses on study on the continuous process of β-aminopropionitrile with fixed bed.First of all, under the conditions of130℃,9.0MPa, LHSV0.8h-1,mole ratio of liquid ammonia and acrylonitrile is20:1, a life test was carried out for1236hours with Dut-0molecular sieve as catalyst by fixed bed. The average selectivity of β-aminopropionitrile is80.2%. The result of the life test has guiding significance for the industrial continuous process of β-aminopropionitrile.Secondly, ammonolysis of3,3’-iminepropionitrile with ammonia use six different molecular sieves as catalyst by fixed bed. The contents of the β-aminopropionitrile are increased with the temperature, but less than3%with the conditions of130-400℃,9.0MPa.The addition reactions of liquid ammonia to acrylonitrile are carried out with three different catalysts. The conversions of acrylonitrile are all100%under the optimized conditions. And the selectivities of β-aminopropionitrile are all more than94%. The experimental results are the best with mordenite as catalyst. And the optimum condition is determined as130℃,7.0MPa, LVSH=0.8h-1,25:1mole ratio of liquid ammonia to acrylonitrile, the selectivities of β-aminopropionitrile reach above95%.The normalization curve of GC is drawed for the production, and the normalization curve of β-aminopropionitrile is not linear.