Study On The Process And Apparent Dynamics For The Preparation Of Diaminopropane By The Ammonolysis Of Dichloropropane

Chloroorganic compounds as wastes in chemical processes have a great impact on the environment. The most efficient waste disposal relies on their transformation to the commercially usable compounds. One of the universal and efficient method of disposal of chloroorganic compounds is ammonolysis. This process allows for the preparation of many usable amines from waste chloroorganic compounds, utilizing readily available and relatively inexpensive ammonia. In this paper, the preparation of 1,2-diaminopropane by the ammonolysis of 1,2-dichloropropane is comprehensively studied.The influence of different catalysts and different solvent systems on the ammonolysis process were researched, and on the basis, orthogonal experimental method was employed. The reaction temperature, reaction time, the molar ratio of liquid ammonia to 1,2-dichloropropane ,the amount of catalyst used were examined to find out the optimized reaction conditions. The results were as follows:â‘  The optimized catalyst of ammonolysis of 1,2-dichloropropane was CuO.â‘¡The ammonolysis process of 1,2-dichloropropane could be undergone under water as the solvent system, and good yield was obtained.â‘¢The orthogonal experiments showed that the optimized reaction conditions of the ammonolysis of 1,2-dichloropropane were : reaction temperature 160°C, reaction time 4h ,the molar ratio of liquid ammonia to 1,2-dichloropropane 40:1, the amount of catalyst 1% accord to the amount of 1,2-dichloropropane used, and under this reaction condition the yields of ammonolysis processes were above 50%.Meanwhile , the apparent kinetics of ammonolysis process was researched by measuring the conversion of 1,2-dichloropropane and the yield of 1,2-diaminopropane. The kinetics model was established as follows:dC_DAp/dt=k₁C_DCP^α-k₂C_DCP^β×C_DAP^γdC_polyamine/dt=k₂C_DCP^β×C_daP^γThe volumes of reaction system were obtained through the simulation by the chemical software ASPEN PLUS .The reaction order , active energy and the pre-exponential factor were determined. The results were as follows:â‘£The chemical software ASPEN PLUS was introduced to simulate the volume of the ammonolysis process, the results showed that the value of gas volumes and liquid volumes were reasonable.⑤The experimental datas from the ammonolysis process were analysed by the software Visual Basic 6.0 and Origin 7.0. The result showed that the apparent reaction order of the ammonolysis main reaction was α≈1.20, the apparent reaction rate constants were 0.55208, 0.93393, 1.44422 under the temperatures 393.15K, 413.15K, 433.15K separatively , and the apparent active energy was 34.062 kJ/mol; the apparent reaction order of the ammonolysis side reaction(only take the dipropylenetriamine in to consideration) was β= 1.58149 , γ=1.10387, the apparent reaction rate constants were 4.82551, 5.40046, 8.79012 under the temperatures 393.15K, 413.15K, 433.15K respectively.