| 摘要 |
FIELD: chemical technology. ^ SUBSTANCE: invention relates to a selective method for removing chloride as NaCl from waste in method for preparing N-phosphonomethyliminodiacetic acid. The waste flow is neutralized with NaOH to pH value about 7, water is evaporated from flow of neutralized waste under atmospheric or lower pressure at temperature from 40°C to 130°C until to precipitation of NaCl. The precipitate is filtered off at temperature from 35°C to 110°C to isolate NaCl from filtrate and NaCl is washed out with saturated saline solution. Invention provides effective removal of NaCl from waste in a method for manufacturing N-phoaphonomethyliminodiacetic acid. ^ EFFECT: improved treatment method. ^ 7 cl, 2 ex |
