A method for treating wastewater from 1,2,3,6-tetrahydrophthalimide crystallization.

Abstract

This invention relates to the field of industrial wastewater treatment technology, specifically disclosing a method for treating 1,2,3,6-tetrahydrophthalimide crystallization wastewater. The method includes the following steps: S1, concentrating the 1,2,3,6-tetrahydrophthalimide crystallization wastewater to 30%–40% of its original volume to obtain a concentrated solution; S2, heating the concentrated solution to 155℃–165℃ and maintaining the temperature for 2.0h–3.0h to obtain a reaction solution; S3, adding water to the reaction solution, then cooling to allow crystallization, separating the solid and liquid phases to obtain a crystallization mother liquor and 1,2,3,6-tetrahydrophthalimide. The method for treating 1,2,3,6-tetrahydrophthalimide crystallization wastewater provided by this invention is simple to operate, easy to implement, and has low equipment maintenance costs. It achieves the goals of resource utilization of raw materials and clean production, and has high economic and environmental benefits.