METHOD OF CLEANING DIETHANOLAMINE SOLUTION FROM IMPURITIES Russian patent published in 2013 - IPC C07C213/10 B01D3/14 

FIELD: chemistry.

SUBSTANCE: method of cleaning diethanolamine solution from impurities involves heating a contaminated aqueous solution of diethanolamine which contains diethanolamine decomposition products and thermally stable salts, followed by fractionation of the obtained vapour-liquid mixture. Said vapour-liquid mixture is fractionated in a fractionation column at pressure of 100-110 kPa and bottom temperature of 170-180°C while feeding inert gas into the bottom part, distilling water; the obtained still residue is fractionated in a vacuum fractionation column at pressure of 1-3 kPa and bottom temperature of 180-185°C while feeding C₉-C₁₃ hydrocarbons into the bottom part and obtaining a distillate - purified diethanolamine and a still residue which contains diethanolamine decomposition products and thermally stable salts.

EFFECT: method increases the degree of extraction of diethanolamine from a contaminated aqueous solution and reduces loss thereof during purification.

2 cl, 1 dwg, 3 tbl