JPH0653948B2 - Treatment method of sulfuric acid acidic solution containing bismuth - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for selectively separating and removing soluble bismuth from impurities accumulated in a sulfuric acid acidic solution of an electrolytic solution in an electrolytic step of copper smelting by a simple operation. It is a thing.

(Prior art and its problems) In electrolytic refining of copper, many metals such as gold, silver, nickel, selenium, tellurium, bismuth, arsenic, and antimony are contained in the anode as the anode, in addition to the target metal copper. include. A part of them elutes with copper, and when they accumulate to a certain concentration or more, they precipitate with copper and deteriorate the quality of electrolytic copper. Therefore, in order to keep these eluted impurities below a certain concentration, it is necessary to purify the electrolytic solution.

Conventionally, as a method for separating bismuth in a copper electrolyte,
A copper electrolytic solution is electrolyzed using an insoluble anode made of lead, etc., and is removed as decoppered slime, a copper removal electrolytic method is neutralized, sodium carbonate is added to the copper electrolytic solution, and hydrogen sulfide gas is blown into the electrolytic solution. There is also a sulfide precipitation method of removing as a sulfide precipitate by the above method, and a method of producing a tampan which removes together with the above-mentioned impurities by concentrating the electrolyte solution in which impurities such as antimony are accumulated to crystallize copper sulfate crystals. However, in each of these methods, a much larger amount of copper is removed together with the impurities to be removed. Therefore, in order to recover this copper, it is re-introduced into the preceding stage of the copper smelting step and repeatedly treated. However, it was not satisfactory for the purpose of removing impurities from the system.

Other removal methods are disclosed in Japanese Patent Laid-Open No. 55-107793.
Precipitation produced by adding and mixing one or both of basic antimony sulfate and basic bismuth sulfate to a sulfuric acid acidic solution containing free sulfuric acid of at least 700 g / arsenic among arsenic, antimony and bismuth. A method for removing arsenic, antimony, and bismuth in a sulfuric acid acidic solution, which is characterized by separating the same, is disclosed, but this method dissolves a large amount of a substance of the same kind as the target substance for purification in the electrolytic solution at one time. Therefore, if the operation is mistaken, there is a danger that the concentration of the impurities in the electrolytic solution is increased.

(Purpose of the invention) The present inventors have solved the above-mentioned problems of the prior art, and separated and removed bismuth contained in the copper electrolytic solution by a simple operation,
As a result of studies to provide a method for removing bismuth in a sulfuric acid acidic solution that reduces the bismuth concentration in the electrolytic solution, it was found that the above object can be achieved very easily by contacting activated carbon with the electrolytic solution. The present invention has been reached.

(Structure of the invention) That is, the gist of the present invention is that a sulfuric acid acidic solution containing bismuth is characterized in that activated carbon is brought into contact with a sulfuric acid acidic solution containing bismuth to adsorb the bismuth to the activated carbon. The processing method is in.

In the present invention, to bring the activated carbon into contact with the copper electrolyte,
A method may be used in which a column is filled with activated carbon to form a layer, and this layer is passed through. Alternatively, the activated carbon may be stirred with an electrolytic solution in a tank, or these two methods may be used in combination. The temperature of the electrolytic solution in contact with the activated carbon may be 60 ° C. which is a normal electrolysis temperature. However, the action of activated carbon is the adsorption of bismuth, so the temperature of the electrolytic solution is preferably 60 ° C. or lower.

Next, the present invention will be specifically described with reference to examples.

The following examples do not limit the scope of the invention.

Example 1 Cu 42 g /, Ni 15 g /, As 5.1 g /, S
b480mg /, Bi93mg /, free sulfuric acid 210g /
200 ml of the copper electrolytic solution of 1 was placed in a 300 ml Erlenmeyer flask with a stopcock, 20 g of different activated carbon was added to each Erlenmeyer flask, and the mixture was stirred for 24 hours. This stirring process is 6
The test piece was immersed in a constant temperature bath at 0 ° C. Bismuth in the electrolytic solution after the treatment was analyzed, and the obtained results are shown in Table 1.

Example 2 By the same method as in Example 1, the electrolytic solution having the same composition as in Example 1 was changed to a liquid temperature of 40 ° C., 60 ° C., 80 ° C., 20 g of each of Tsurumi Coal powder activated carbon was added, and the mixture was placed in a constant temperature bath. Table 2 shows the analytical values of bismuth in the electrolytic solution after stirring for 24 hours.

As is clear from the above results, according to the present invention, it is possible to easily separate bismuth from other elements with good selectivity.

(Effects of the Invention) The present invention having the above-described configuration exhibits the following effects.

(1) Since the activated carbon and the electrolytic solution are only brought into contact with each other, there is no consumption of free sulfuric acid and mixing of different metals into the solution unlike the conventional neutralization method.

(2) When the purification target of the electrolytic solution is bismuth, the solution from which bismuth has been removed according to the present invention can be sent to the electrolysis process as it is or in part, reducing the load of the Danpan manufacturing process and the decoppering electrolysis process. it can.

Claims (1)

[Claims] 1. A method for treating an acidic sulfuric acid solution containing bismuth, which comprises contacting activated carbon with an acidic sulfuric acid solution containing bismuth to adsorb the bismuth on the activated carbon.