| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for distillating and purifying ethylenediamine (EDA) from a mixture containing N-methyl ethylenediamine (Me-EDA) as an impurity.SOLUTION: There is provided a method of purifying ethylenediamine including a post treatment by distillating a mixture containing EDA, Me-EDA and water with ethylenediamine of at least 99.5 mass%, concentration of N-methyl ethylenediamine in a range of 0.005 to 0.15 mass%, with introducing the mixture to a distillation tower run under tower top pressure from 10 mbar to 4 bar, where a mass ratio of water/ethylenediamine in the mixture is aX:Y, where X is mass percentage at the azeotropic point of two-component mixture of water and ethylenediamine at the tower top pressure, Y is mass percentage of ethylenediamine at the azeotropic point of two-component mixture of water and ethylenediamine at the tower top pressure, and a is a real number of 0.9 or more.SELECTED DRAWING: None |
