GALLIUM PRODUCTION METHOD FROM ALKALI-ALUMINATE SOLUTIONS OF ALUMINA INDUSTRY Russian patent published in 2015 - IPC C25C1/22 C22B58/00 

FIELD: electricity.

SUBSTANCE: method includes the preparation of a base mixture by mixing a mother solution and a bypass solution in the ratio equal to 1: (0.8÷0.9) at constant stirring and air treatment in a quantity of 0.4-0.6 Nm³/h per 1 m³ of the mixture at a temperature of 70-90°C, then lime is introduced in a quantity of 28-30 kg CaO_act. per 100 kg of Al₂O₃ in the solution with the further detachment of a buildup deposit. Then the first stage of electrolysis is carried out at the current concentration of 3.0-3.5 kA/m³ and temperature of 40-50°C using zincate solution as an electrolyte. The second stage is carried out using the base mixture as the electrolyte at the current concentration of 5.6-6.0 kA/m³ and temperature of 28-35°C. At the third stage, upon setting the constant value of the cathode potential, concentration of reverse polarity current is decreased up to 1.5-2.0 kA/m³ and the solution of a cathode deposit is made in the receiving solution containing 85-90 kg/m³ Na₂O_caustic. The fourth stage is carried out at the current concentration of 1.25-1.50 kA/m³ using the receiving solution as the electrolyte; at that the cathode deposit is dissolved in a waste electrolyte of the second stage at a temperature of 60-70°C by a reverse polarity current with the current concentration of 3-4 kA/m³.

EFFECT: increased relative productivity, reduced power consumption, production of commercial gallium with high purity.

2 cl, 2 tbl, 1 ex