Method for enriching and recovering indium from zinc oxide acid supernate

Abstract

The invention discloses a method for enriching and recovering indium from zinc oxide acid supernate, which is characterized by comprising the following: a step A of reduction and purification, which is to put iron powder into zinc oxide acid supernate to reduce Fe<3+> into Fe<2+> and removing the impurities from the solution at the same time; a step B of liquid and solid separation, which is to filter the solution obtained by the step A to obtain reduced and purified solution and reduced and purified slag; and a step C of replacing precipitated indium, which is to add zinc scum into the reduced and purified solution obtained by the step B to replace the precipitated indium, filtering to obtain filtrate and indium-enriched slag, recovering indium from the enriched slag and returning the filtrate to a zinc system to recovery zinc. The method is mainly used in wet-method zinc making plants for enriching and recovering indium from zinc oxide acid supernate.

Description

technical field [0001] The invention relates to a method for enriching and recovering indium, in particular to a method for enriching and recovering indium from zinc oxide supernatant. technical background [0002] Indium is a rare dispersed metal. Because of its unique and excellent physical and chemical properties, it is widely used in high-tech fields such as electronic computers, energy, electronics, optoelectronics, national defense, aerospace, nuclear industry, chemical industry and modern information industry. , and industries such as the manufacture of fusible alloys. At home and abroad so far, almost no single indium deposits and indium-based deposits have been found, and most of the indium exists in sphalerite and galena in a sparse state. Therefore, most of the raw materials for recovering indium come from the indium-enriched slag, a by-product produced during the lead-zinc smelting process. That is, the leaching slag produced in the zinc smelting process is vol...

AI Technical Summary

Problems solved by technology

The process of substituting zinc powder for indium sinking requires a large amount of zinc powder, and the unit consumption of enriched zinc powder per kilogram of indium is 60-70kg, and the cost is relatively high; moreover, due to the high activity of zinc powder and fast reaction speed, it is easy to produce a large amount of highly toxic AsH 3 Gas, while adding zinc powder to prevent explosion, it is necessary to add water while adding zinc powder, which also reduces the efficiency of sinking indium

Although the zinc oxide calcine neutralization and indium precipitation process is low in cost, due to the high content of Fe and other impurities in the zinc oxide calcine, the produced indium-enriched slag contains low In grade, and the indium-enriched slag contains high Fe and other impurities. , and difficult to filter

Nowadays, due to the decrease in the grade of indium in the raw materials and the increase in the content of impurities such as Fe and Cu, it is difficult to obtain high-grade indium-enriched slag by directly replacing indium with zinc powder and indium with zinc oxide calcination. The slag contains low indium and high impurity content, which greatly increases the subsequent recovery cost of indium

Therefore, it is difficult to obtain indium-enriched slag with higher In grade and lower impurity content from the process of enriching and recovering indium from zinc oxide supernatant in the prior art. How to obtain higher grade and lower impurity content from the above raw materials Indium-enriched slag and reduced production costs are subjects to be further explored

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