Method for electrochemical deep removal of water-soluble extractant in tantalum liquid in potassium fluotantalate preparation process

Abstract

The invention discloses a method for electrochemical deep removal of a water-soluble extractant in a tantalum liquid in the potassium fluotantalate preparation process, and belongs to the technical field of deep removal of the water-soluble organic extractant in wet metallurgy extraction separation and purification processes. The method comprises the following steps: putting the tantalum liquid extracted and separated in the potassium fluotantalate production process flow into a reaction container; taking a tantalum rod as an anode and a tantalum material as an anode, immersing the cathode andthe anode into the tantalum liquid, applying an electric field of 1.5-3 V to the cathode and the anode, performing constant-potential electrolysis until the concentration of the water-soluble extractant dissolved in an aqueous tantalum solution is not changed, and continuously and uniformly introducing air from the bottom of a reaction container in the electrolysis process to achieve physical stripping; and carrying out a subsequent process for preparing potassium fluotantalate after the electrolysis is finished in order to obtain high-purity potassium fluotantalate. The method can effectively remove the water-soluble extractant dissolved in the solution deeply and prepares the low-carbon high-purity potassium fluotantalate. The method has the advantages of low energy consumption, and simplicity in operation.

Description

technical field [0001] The invention relates to the technical field of deep removal of water-soluble organic extractants in the process of hydrometallurgical extraction, separation and purification, in particular to a method for deep electrochemical removal of water-soluble extractants from tantalum liquid during the preparation of potassium fluorotantalate. Background technique [0002] The production of high-purity metal tantalum is based on high-purity potassium fluorotantalate as raw material, which is obtained by thermal reduction of metal sodium. Due to the similar chemical properties of tantalum and niobium, they coexist with each other in nature, and it is extremely difficult to separate them. At present, most manufacturers at home and abroad use organic extraction method to separate and purify tantalum and niobium in the process of producing potassium fluorotantalate. The main process flow is as follows: figure 1 shown. In the extraction and separation process, th...

AI Technical Summary

Problems solved by technology

[0003] For the residual organic extractant in the production process of high-purity potassium fluorotantalate, in order to prevent it from being further polluted, the air stripping method is often used to physically remove it, but because the organic extractant has a certain compatibility with water For example, the solubility of MIBK in aqueous solution is 2±0.2%. The removal effect of these organic extractants dissolved in tantalum liquid by physical stripping is not obvious, so that the carbon content in the final potassium fluorotantalate crystal is above 16ppm , unable to meet the preparation requirements of ultra-high-purity tantalum

The method of physical stripping can only remove the entrained organic extractant, but the dissolved water-soluble extractant cannot be removed by physical stripping. The deep removal of the organic extractant dissolved in the tantalum liquid after extraction and separation is the best way to prepare low-carbon high-purity fluorine Key Questions for Potassium Tantalate

Images