Gallium electrolytic refining method

Abstract

The invention discloses a gallium electrolytic refining method, which relates to a gallium electrolytic refining process, in particular to a method for improving electrode materials in a refining process. The method is characterized in that: in the electrolytic refining process, a metal gallium sheet is used in places of a foil sheet as a cathode; and a platinum wire serving as a cathode lead wire is provided with a clean FEP tube protective layer. In the method, when the measures are carried out, the electrochemical corrosion problem of the foil is solved, the cathode foil sheet is replaced completely, the foil content in the electrolytic product is reduced from 0.08 to 0.2ppm before improvement to 0.01 ppm which is lower than a detection limit of glow discharge mass spectrometry, the product quality is improved, and operation flow is simplified.

Description

technical field [0001] A gallium electrolytic refining method relates to a gallium electrolytic refining process, in particular to an improved method for electrode materials in the refining process. Background technique [0002] The electrolytic refining method is to use the crude gallium to be purified as the anode, the high-purity gallium as the cathode, and the NaOH aqueous solution as the electrolyte under the temperature above the melting point of gallium (29.78°C), and make the metal coarse gallium on the anode under the action of an external current. After dissolving into the electrolyte, it migrates to the cathode through ion migration and discharges and precipitates at the cathode to obtain high-purity gallium. The method has the advantages of simple process and easy operation, and can produce 99.999%-99.9999% high-purity metal gallium. [0003] Pure platinum is used as electrode in high-purity gallium electrolytic refining, because H 2 High affinity to platinum, ...

AI Technical Summary

Problems solved by technology

[0003] Pure platinum is used as electrode in high-purity gallium electrolytic refining, because H 2 High affinity to platinum, low overpotential, precipitation potential GaO on the surface of platinum 2 - / Ga is high, so when Ga is precipitated at the cathode, hydrogen must be precipitated, which will accelerate the process of NaOH, H 2 The evaporation of O destroys the dynamic balance of electrolysis, causing the current efficiency to drop, and only H is precipitated in the later stage of electrolysis. 2 There will be no Ga precipitation, resulting in extremely high residual electrode rate

[0004] On the other hand, electrolytic refining uses platinum wire as the electrode lead and platinum sheet as the cathode electrode material. Each tank needs to be equipped with platinum electrode materials, which is expensive at one time.

Practice has proved that in the electrolysis process, there is a micro-electrochemical reaction between the platinum electrode material and the electrolyte, which causes the corrosion and consumption of the precious metal platinum electrode material

Platinum electrodes need to be treated with aqua regia before and after electrolysis, which not only causes the loss of platinum, but also pollutes people, objects and the environment.