The removing of fluorine from the new liquid of the zinc smelting system by chemical precipitation method using a new type of composite defluorination agent D-3 was studied. The effects of reaction temperature, reaction time, dosage of defluorination agent added and the initial pH of the new solution on the defluorination rate were investigated. The results show that the reaction time has the greatest influence on the defluorination rate, followed by the dosage of defluorination agent, then the reaction temperature, and the initial pH of the fluorine-containing new solution has the least influence. Based on the results of the single-factor test and combined with the actual production situation, the optimal fluoride removal conditions are determined as follows:the addition amount of D-3 defluorination agent is 40 times, the reaction temperature is 70 ℃, the reaction time is 1.0 h, and when the initial pH of the new fluorine-containing solution is approximately 5.0, the defluorination rate under the conditions is approximately 75%, and the residue rate is 12%. When the fluorine content in the new liquid exceeds 200 mg/L, the defluorination rate exceeds 75%, and the defluorination effect is better.

hydrometallurgical zinc smelting  /  defluorination agent  /  chemical precipitation method  /  fluorine  /  removal