Activation extraction separation method for fluorine and chloride ions in zinc sulfate solution

Abstract

The invention relates to an activation extraction separation method for fluorine and chloride ions in a zinc sulfate solution, which comprises the following steps: acid adjustment activation: adding concentrated sulfuric acid into the zinc sulfate solution to adjust the pH value and temperature, and mixing and blending the solution with an activating agent to damage the fluorine-containing metal complexes in the solution and decompose the fluorine-containing metal complexes into free-state fluorine ions and convert into HF molecules; extraction separation: separating the fluorine and chloride ions in the activated zinc sulfate solution by use of an extraction agent to obtain an organic phase loaded with fluorine and chloride and a raffinate with low content of fluorine and chloride; raffinate purification: removing most of the extraction organic phase through multi-segment standing clarification and ultrasonic air flotation; performing deep adsorption by use of powdery active carbon to remove residual organic phase in the raffinate to obtain adsorption residue and qualified raffinate; and impurity washing and back extraction of the loaded organic phase. According to the method provided by the invention, the key reason hindering the extraction fluorine removal effect in the zinc sulfate solution as well as the crystallization and scaling in the back extraction process is found so that the different problems are simple and easy to impellent. The fluorine removal rate exceeds 60%, and the chlorine removal rate reaches about 90%. The liquid after impurity washing and the liquid after back extraction directly return to an alkali washing process of a zinc hydrometallurgy system to be comprehensively utilized.

Description

technical field [0001] The invention belongs to the technical field of purification of zinc smelting solution by wet method, and specifically relates to a method for activating, extracting and separating fluorine and chloride ions from zinc sulfate solution, and is especially suitable for purifying zinc sulfate solution with high content of fluorine and chloride ions in zinc smelting by wet method separate. Background technique [0002] In the wet zinc smelting industry, the fluorine and chloride ions in the zinc sulfate solution have always been technical difficulties and forbidden areas in this industry. As we all know, in the process of zinc electrowinning, if the concentration of chloride ions in the zinc sulfate solution is too high, the cathode and anode plates will be severely corroded, resulting in a decrease in the life of the anode and cathode plates, and a decrease in the quality of zinc precipitated from the cathode. However, the high concentration of fluoride i...

AI Technical Summary

Problems solved by technology

[0011] In short, the existing technologies for removing fluoride and chloride ions in zinc sulfate solution still have various deficiencies or limitations, and it is still necessary to develop new technological routes to improve them.

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