The invention provides a method for preparing 1, 5-dimethyl-2-
nitryl imido-hexahydro-1, 3, 5-
triazine from
clothianidin wastewater, and relates to the technical field of
chemical preparation, the method comprises the following steps: Sp1, preparing a reaction liquid 1: standing
clothianidin acid
wastewater for layering, taking the upper-layer acid
wastewater, and carrying out reduced pressure
distillation to obtain an acid distillate and a mother solution; and dropwise adding liquid caustic soda into the
mother liquor to adjust the pH value to be neutral, then continuously dropwise adding the liquid caustic soda to adjust the pH value to be alkaline, and meanwhile, heating to absorb
ethylamine to obtain a reaction solution 1, and the method significantly reduces the wastewater generation amount, the
acid strength and the
environmental risk. According to the method, the
clothianidin acid wastewater is subjected to targeted treatment,
ethylamine in the clothianidin acid wastewater is effectively recovered and directly used for synthesis of downstream
triazine compounds, the defect that a large amount of high-
salinity wastewater is generated in traditional
neutralization treatment is overcome, the direct
discharge amount of strong-acidity wastewater is reduced, the risks of water acidification and
ammonia nitrogen pollution are reduced, and the method is suitable for industrial production. The environment protection is facilitated.