Non-volatile method for extracting zinc, iron and indium from solution of zinc, iron and indium

Abstract

The invention relates to a non-volatile method for extracting zinc, iron and indium from the solution of zinc, iron and indium. The method comprises the following steps of: a, separating the indium, namely adding sub-zinc oxide into the solution containing the zinc, the iron and the indium at the temperature of between 20 and 95 DEG C to perform indium-zinc separation directly to obtain zinc liquid and indium precipitate slag, and subjecting zinc liquid to impurity removal and purification and connecting the zinc liquid with power to accumulate the zinc, wherein in the process, the pH value is controlled to be 3.2 to 5.4 and the time is 0.5 to 3.0 hours; b, leaching, namely leaching the separated indium precipitate slag with sulfuric acid and supplying peracid to the leached slag to leach zinc; c, extracting, namely adding an extracting agent into the liquid rich in indium to perform extraction, and subjecting the extract liquid to back extraction, displacement, electrolysis and the like to further extract the indium; d, precipitating the iron, namely adjusting the pH value of the raffinate to obtain iron slag and iron-removed liquid through precipitation; and e, precipitating the zinc, namely adjusting the pH value of the iron-removed liquid and precipitating the zinc, returning the zinc slag to a zinc system to process the zinc slag and returning the mother liquor to the leaching step b. The method has the advantages of great improvement on the recovery rate of the indium, no volatilization, simple process and no ferrous and ferric conversion and reduction.

Description

【Technical field】 [0001] The invention relates to a method for extracting indium, in particular to a method for extracting indium from a zinc-iron-indium solution. 【Background technique】 [0002] At present, there are two methods commonly used to extract zinc, iron, and indium from zinc-iron-indium solution. One method is: iron removal by jarosite method - volatilization of indium by volatilization of jarosite slag - leaching of indium-containing smoke dust - indium-containing Liquid extraction and stripping, the disadvantage of this method is high cost and low recovery rate: due to the relatively high cost of iron vitriol precipitation, the volatilization cost and maintenance cost of the volatilization kiln also directly lead to high processing costs of indium, and in volatilization The sulfur dioxide produced in the kiln treatment process must be absorbed and treated, which greatly increases the investment cost and cost consumption. At the same time, because the volatiliza...

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Problems solved by technology

[0002] At present, there are two methods commonly used to extract zinc, iron, and indium from zinc-iron-indium solution. One method is: iron removal by jarosite method - volatilization of indium by volatilization of jarosite slag - leaching of indium-containing smoke dust - indium-containing Liquid extraction and stripping, the disadvantage of this method is high cost and low recovery rate: due to the relatively high cost of iron vitriol precipitation, the volatilization cost and maintenance cost of the volatilization kiln also directly lead to high processing costs of indium, and in volatilization The sulfur dioxide produced in the kiln treatment process must be absorbed and treated, which greatly increases the investment cost and cost consumption. At the same time, because the volatilization control in the volatilization kiln treatment is not easy to control, the recovery rate of indium is only about 70-80%. Another method is to neutralize and precipitate indium after the ferric iron in the zinc-iron-indium solution is reduced to ferrous iron by a reducing agent, and then extract and strip indium after the obtained indium slag is redissolved. Volatilization kiln, and the reducing agent used is zinc sulfide concentrate, which avoids the input cost of other reducing agents, but using this method to convert and reduce ferric iron requires a higher temperature and a longer time, and after the precipitation of indium, the divalent iron Iron needs to be oxidized to ferric iron and then goethite method is used to remove iron. Since the volume of iron and zinc does not change greatly during the process of conversion, indium precipitation, goethite iron removal and other processes, the treatment capacity Large, long processing time, high processing cost

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