Method for preparing tungsten from WO3

Abstract

The invention relates to a method for preparing tungsten from WO3, belonging to the technical field of electrolysis and electrophoresis. The method is used for realizing one-step electrodeposition to obtain WO3 from with fused salt as medium under the action of pulse direct current. The method is characterized in that a component comprising NaCl, KCl and NaWO4 is used as medium, wherein the molar ratio of NaCl to KCl to NaWO4 is 2:2:(0.01-2):2:0.05, and the powdered WO3 which is 10-20 wt% of the fused salt medium is added; and after impurity removal by pre-electrolysis, pure tungsten is obtained by electrodeposition at an electrodeposition temperature of 650-750 DEG C, electrodeposition time of 1-3 hours and current density of 300-600 A / m2. The method provided by the invention has the following characteristics: (1) the component of the fused salt is common cheap agent, is easily-accessible and has low cost and less consumption; (2) the production technology has short process and wide parameter control range, and is easy to operate and implement; (3) the electrodeposition temperature is low, so that the fused salt does not volatilize; and (4) the component of the fused salt can be ensured to not to change with the prolongation of the electrodeposition time, so as to ensure the stability of electrodeposition process. The method has good prospect in tungsten production and applications.

Description

technical field [0001] The present invention relates to a kind of by WO 3 A method for preparing metal tungsten, especially a method for electrodepositing tungsten in a molten salt system, belongs to the technical field of electrolysis and electrophoresis. Background technique [0002] The content of tungsten in the earth's crust is small, accounting for only 0.007% of the weight of the earth's crust. Metallic tungsten has not been found in nature, and about 15 kinds of tungsten minerals have been discovered so far, among which wolframite and scheelite are the most important, and they are the main raw materials for tungsten metallurgy. Due to the special nature of metal tungsten, the extraction of metal tungsten from wolframite or scheelite cannot be obtained through high-temperature smelting process like extracting iron from iron ore or extracting copper from copper ore to obtain liquid metal with higher grade. The leaching-purification or extraction-roasting process has ...

AI Technical Summary

Problems solved by technology

However, due to the strong corrosiveness of phosphate, its application is limited, and at 700 ° C, the brittle layer of β-tungsten is mainly deposited.

in Na 2 WO 4 -Li 2 WO 4 -WO 3 , Na 2 WO 4 -WO 3 、Na 2 WO 4 -ZnO-WO 3 、NaF-NaCl-WO 3 In the system, the tungsten deposition layer with smaller crystal grains is obtained by using the pulse electrodeposition method, thereby improving the quality of the deposition layer, but the electrodeposition temperature of these systems is very high, and as the electrodeposition progresses, the melting The salt composition changes greatly, resulting in unstable deposition effect