Stirring water-washing method and device for producing tantalum powder by reducing potassium fluotantalate via metallic sodium

Abstract

The invention relates to a stirring water-washing method and device for producing tantalum powder by reducing potassium fluotantalate via metallic sodium. The water-washing method comprises the following steps of: performing stirring water-washing on the tantalum powder obtained by reducing potassium fluotantalate (K2TaF7) via metallic sodium (Na) which removes alkali metal haloids in an electrolyte solution, so as to remove harmful and indissolvable ultrafine-particle impurities in the tantalum powder; and then performing acid-washing and drying to obtain the initial tantalum powder. The method is high in the yield of tantalum powder; and the obtained tantalum powder is high in purity, good in particle size distribution and porosity, and especially suitable for manufacturing a tantalum electrolytic capacitor.

Description

technical field [0001] The invention relates to the field of hydrometallurgy, in particular to a metal sodium (Na) reduction of potassium fluorotantalate (K 2 TaF 7 ) A stirring and washing method and device for producing tantalum powder. Background technique [0002] Tantalum is a rare metal, mainly used in the electronics industry, chemical equipment, metal cutting, aerospace and other industries. In recent years, the consumption of tantalum has grown rapidly, but resources are scarce. Therefore, it is a development trend of the tantalum industry to effectively utilize tantalum resources and reduce the waste of tantalum. [0003] In the electronics industry, the main use of tantalum powder is to manufacture tantalum electrolytic capacitors. In recent years, capacitors require a high degree of miniaturization, high reliability and chip compatibility. In the high-end capacitor market, tantalum electrolytic capacitors can continuously meet the development trend of the abov...

AI Technical Summary

Problems solved by technology

If the settling time is too short during the stirring and washing process, some tantalum powders larger than 100nm will be seriously lost, and the yield of tantalum powder will be reduced. Prolonged settling time during the process will prolong the production cycle. At the same time, a large number of harmful and insoluble ultrafine impurity particles will also enter the tantalum powder, which will seriously affect the physical properties of the product, resulting in increased leakage current, reduced specific volume, and low impedance of the manufactured tantalum electrolytic capacitor. increase, reliability decreases; at the same time, it will also increase the content of oxygen (O), potassium (K), sodium (Na) and fluorine (F) in tantalum powder, which seriously affects the electrical properties of tantalum powder

And the stirring water washing device provided by Chinese patent CN102191389A adopts the mode of vertical stirring of the stirring paddle, which is easy to form a vortex during the stirring process, so that the stirring is not sufficient, the washing effect is not good, and the impurities mixed in the tantalum powder cannot be fully removed, so that the oxygen in the tantalum powder High content of (O), potassium (K), sodium (Na), carbon (C) and fluorine (F) will seriously affect the electrical properties of tantalum powder

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