Method for separating and extracting indium and gallium from indium-gallium solution

Abstract

The invention relates to a method for separating and extracting indium and gallium from an indium-gallium solution. The method comprises the steps that (1) extraction is carried out, i.e., organic phosphoric acid is adopted as an extraction agent, and diluents are added, so that an organic phase is obtained, and the organic phase is added to liquid to be extracted for extraction after pH value is adjusted; (2) reverse extraction of indium is carried out, i.e., reverse extraction is conducted on the extracted phase in the step (1) with concentrated hydrochloric acid, so that an indium-enriched aqueous phase is obtained; (3) reverse extraction of gallium is carried out, i.e., reverse extraction is conducted on the organic phase subjected to reverse extraction in the step (2) with an oxalic acid solution, so that a gallium-enriched aqueous phase is obtained; (4) zinc or aluminum is added into the indium-enriched aqueous phase obtained in the step (2) to obtain indium through replacement, or alkaline substances are added to obtain indium hydroxide sediment; (5) precipitants are added into the gallium-enriched water phase obtained in the step (3) to obtain calcium oxalate, filtration is carried out to remove calcium oxalate, and replacement is carried out on liquid obtained after filtration with zinc or aluminum to obtain the simple substance gallium, or alkaline substances are added to obtain gallium hydroxide sediment. According to the method, two elements are recovered by conducting extraction once and reverse extraction twice, separation is complete, the recovery rate is high, operation is easy, and production cost is reduced.

Description

technical field [0001] The invention belongs to the field of hydrometallurgy, in particular to a method for separating and extracting indium and gallium from an indium gallium solution. Background technique [0002] Indium and gallium, as rare metal elements, are important industrial materials and are often used in alloys, sensors and semiconductors. Due to the scarcity of the two elements, recycling indium or gallium from some industrial waste or electronic waste has become an important way. Indium gallium often exists in some industrial wastes at the same time, such as smelting zinc slag, indium gallium alloy target waste and discarded indium gallium arsenic detectors. The separation of the two elements will inevitably be involved in the recycling process. However, the properties of indium and gallium are relatively similar in the ionic state of solution, and it is difficult to separate and extract, so it has become a common problem in the industry. [0003] The existing...

AI Technical Summary

Problems solved by technology

[0003] The existing method of separating indium and gallium from the solution is mainly to extract indium with P204 extractant first, and then recover gallium from the raffinate, but when extracting indium, some gallium will be co-extracted into the organic phase, resulting in a low recovery rate of gallium

In addition, there are also literature reports to separate by hydrolysis and precipitation, but the hydrolysis pH values ​​of the two are relatively close, the control is difficult, and it is easy to entrain and co-precipitate, resulting in impure product or low recovery rate