JPH06279879A - Method for removing sb and/or bi from sulfuric acid-acidified aqueous solution containing sb and/or bi - Google Patents

Abstract

PURPOSE:To remove Sb and/or Bi from a sulfuric acid-acidified aq. soln. contg. Sb and/or Bi. CONSTITUTION:Sb and/or Bi are removed from a sulfuric acid-acidified aq. soln. contg. Sb and/or Bi. In this case, the aq. soln. is heated at >=100 deg.C, a Pb compd. is added to the aq. soln. which is heated at >=100 deg.C, or a material contg. Pb is added to the aq. soln. which is heated at >=100 deg.C. Consequently, the process is simplified and easily controlled, and Sb and/or Bi, which are hardly separated by the well-known process, are efficiently removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing Sb and / or Bi from an acidic aqueous sulfuric acid solution containing Sb and / or Bi.

[0002]

2. Description of the Related Art In non-ferrous smelting, since various ores are used as raw materials, it is unavoidable that many kinds of metal elements are mixed in as impurities.
It also includes As, Sb, and Bi. Especially in copper smelting, the contents of Sb and Bi tend to increase in recent years,
It is practically difficult to completely remove it by the dry method, and therefore, even if it is small in quantity, As, Sb, Bi
Is contained in crude copper (copper anode) and is brought to the next electrolytic refining step. As, Sb, contained in crude copper (copper anode)
Bi and the like are partially eluted in the electrolytic solution, and the uneluted portion is accumulated at the bottom of the electrolytic cell as anode slime. Eluted As, Sb, B
When the concentration of impurities such as i rises, they are deposited on the copper cathode. Therefore, the concentration of As in the electrolytic solution is usually maintained at around 5 to 10 g / l, and the concentrations of Sb and Bi are maintained at around 0.3 to 0.5 g / l so that the impurity concentration is not deposited on the copper cathode. ing.

As a general method for maintaining the concentration of these impurities, a part of the electrolytic solution is taken out into another electrolytic cell to perform so-called decoppering electrolysis. In the latter stage of decoppering electrolysis, Cu is added to the cathode together with As. , Sb, Bi, etc. are deposited in the form of particles or powder, and also at the bottom of the electrolytic cell. Electrolytically precipitated copper is a name of those skilled in the art, and those that can be scraped off from the cathode and those that precipitate on the bottom of the tank are generally referred to as electrolytically precipitated copper.

This electrolytically precipitated copper is generally repeated in the copper smelting process, but a large amount of impurities circulate in the smelting process, which is not a preferable method. Therefore, conventionally, a dry method or a wet method for removing impurities in electrolytically precipitated copper out of the smelting system has been proposed. The dry method is not only costly due to the treatment of exhaust gas and dust containing arsenous acid (As ₂ O ₃ ), but is not a preferable method from the working environment. I need to think.

As a wet treatment method, for example, electrolytically precipitated copper is brought into contact with a sulfuric acid solution in the presence of an oxygen-containing gas, and Cu is added.
After leaching As and As, the leaching solution is cooled or arsenic sulfide and an aqueous hydrogen peroxide solution are added to the leaching solution to obtain C, respectively.
A method for separating u from As (Japanese Patent Laid-Open No. 59-74245, Japanese Patent Laid-Open No.
9-83936), etc., but the separated aqueous solutions each contained a considerable amount of impurities (Sb, Bi, etc.). The form of Cu and As separated and recovered from the obtained aqueous solution is generally tanpan (CuSO ₄ .5H ₂
O) or copper sulfide (CuS) and arsenous acid (As
₂ O ₃ ) but the above impurities are inevitably contained. Crude copper sulfide is repeated in copper smelting,
Crude arsenous acid becomes a product after being re-refined, but there are problems that the amount of the impurities is repeated in copper smelting or the removal of the impurities from crude tanpan and crude arsenous acid is difficult.

As a method for solving the above problems, for example, a sulfuric acid acidic aqueous solution obtained by leaching Cu or As is added with p.
Sulfurous acid gas was blown while maintaining H1.5 to 2.5, the precipitate formed after cooling was separated, and Cu containing less Sb and Bi,
Method for producing As-containing sulfuric acid aqueous solution (JP-A-61-23)
5521), and electrolytically precipitated copper is brought into contact with an acidic sulfuric acid aqueous solution containing iron ions in the presence of an oxygen-containing gas to produce an acidic sulfuric acid aqueous solution containing Cu and As with less Sb and Bi (JP-A-61-69930). ) Alternatively, a sulfuric acid aqueous solution is added to the electrolytically precipitated copper, and 5 to 15% by volume of sulfurous acid gas and 15% by volume or less of an oxygen-containing gas are blown into the resulting leachate to bring it into contact with activated carbon. , A method of producing a sulfuric acid aqueous solution containing Cu and As containing less Bi (JP-A-61-83625), and further, leaching As by contacting electrolytically precipitated copper with an aqueous alkali hydroxide solution in the presence of an oxygen-containing gas. A method for producing a Cu-containing sulfuric acid acid aqueous solution containing less Sb and Bi by contacting the insoluble residue and sulfuric acid solution after obtaining an As-containing alkaline aqueous solution containing less Sb and Bi by solid-liquid separation. Sho 6 2-77431) etc.

Although it is possible to produce an aqueous solution containing Cu and As containing a small amount of Sb and Bi by these methods,
It is necessary to control the amount of iron ions, the amount of sulfurous acid gas, or the amount of alkali hydroxide, and Sb,
There is an increase in the leaching rate of Bi or a decrease in the leaching rate of copper and arsenic. When sulfurous acid gas is added, not only the reduction of Sb ⁵⁺ to Sb ³⁺ but also the reduction of As ⁵⁺ takes place and
^{Since 3+} is generated, it is difficult to obtain a liquid having a high As concentration, and the leaching rate of As decreases. Further, in the case of adding iron ions, since Sb and Bi are co-precipitated in the compound of As and Fe, it is difficult to obtain a liquid having a high As concentration, and the leaching rate of As decreases. Iron ion amount, sulfurous acid gas amount, or
The appropriate amount of the alkali hydroxide is determined by the amount of Cu in the electrolytically precipitated copper, or the amount of As.
There is a problem that the separation quality of Sb, Bi and Cu, As is likely to fluctuate because the As quality varies.

As another method for removing Sb and Bi in the copper electrolytic solution, there is a method by adsorption using a chelate resin (Japanese Patent Publication No. 62-6751, Japanese Patent Publication No. 5-5901). in this way,
Although it has an advantage that the removal efficiency of Sb and Bi is high, it has a drawback that it requires a large amount of expensive hydrochloric acid, nitric acid and the like for eluting Sb and Bi adsorbed on the resin, resulting in a high cost.

[0009]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present inventors have keenly studied a method for removing Sb and / or Bi from an aqueous sulfuric acid solution containing Sb and / or Bi. As a result of continued examination, Sb and / or B
A sulfuric acid acidic aqueous solution containing i is heat-treated at 100 ° C. or higher, or a Pb compound is added to the sulfuric acid acidic aqueous solution and heat-treated at 100 ° C. or higher. Further, a substance containing Pb in the sulfuric acid acidic aqueous solution is added. It was found that Sb and Bi in the treatment liquid were removed by adding and heating at 100 ° C. or higher. Therefore, an object of the present invention is to provide a method for removing Sb and / or Bi from a sulfuric acid aqueous solution containing Sb and / or Bi.

[0010]

That is, the present invention is characterized in that (1) a sulfuric acid acidic aqueous solution containing Sb and / or Bi is heated at 100 ° C. or higher.
Sb from acidic aqueous sulfuric acid solution containing b and / or Bi
And / or a method for removing Bi. (2) Sb and / or Sb and / or Sb and / or Bi from the sulfuric acid aqueous solution containing Sb and / or Bi as described in (1) above, characterized in that a Pb compound is added to the sulfuric acid aqueous solution containing Sb and / or Bi. How to remove Bi. (3) A substance containing Pb is added to an acidic sulfuric acid aqueous solution containing Sb and / or Bi,
The method for removing Sb and / or Bi from an acidic aqueous sulfuric acid solution containing Sb and / or Bi according to (1) above. (4) Sb and / or Sb and / or (3) described above, wherein the sulfuric acid acidic aqueous solution containing Sb and / or Bi is obtained by leaching electrolytically precipitated copper at less than 100 ° C. Or S from an acidic sulfuric acid aqueous solution containing Bi
b and / or Bi removal method. Regarding

[0011]

DETAILED DESCRIPTION OF THE INVENTION A specific and detailed description will be given to facilitate understanding of the present invention. The sulfuric acid aqueous solution containing Sb and / or Bi, which is the object of the present invention, is not particularly limited. In copper smelting, an aqueous solution or the like obtained by leaching electrolytically precipitated copper or anode slime with sulfuric acid is exemplified. Hereinafter, a case where electrolytically precipitated copper is leached with sulfuric acid will be described as an example, but the present invention is not limited thereto.

In the leaching reaction of electrolytically precipitated copper with a sulfuric acid solution, the reaction according to the following formula proceeds, Cu is oxidized to Cu ²⁺ , As is oxidized to As ⁵⁺ , and the large amount of Cu and As. The part is leached. Cu + H ₂ SO ₄ + 1/2 ・ O ₂ → CuSO ₄ + H ₂ O ・ ・ ・ ・ (1) 2As + 5/2 ・ O ₂ + 3H ₂ O → 2H ₃ AsO ₄・ ・ ・ ・ (2 ) The amount of sulfuric acid used is preferably 1.0 to 1.2 with respect to the amount of Cu.
When the amount is less than 1.0 equivalent, the leachate becomes weakly acidic, and precipitates such as Cu ₃ AsO ₄ are formed to reduce the leaching rate of Cu and As. If it exceeds 1.2 equivalents, Cu, As
Although it does not affect the leaching rate of, since the amount of sulfuric acid used increases,
Not preferable. The concentration of Cu and As is not particularly limited,
If the solubility is exceeded, the leaching rate of Cu and As will decrease.
It is preferably not more than the solubility of Cu ²⁺ and As ⁵⁺ .

When the electrolytically precipitated copper and the sulfuric acid acidic solution are brought into contact with each other at a temperature of less than 100 ° C. in the presence of an oxygen-containing gas to perform leaching treatment, as the concentration of As increases in the presence of Cu and As. In particular, the leaching rate of Sb becomes high and Bi
Is also slightly leached. The form of leached Sb is As
When the concentration is low, the form is Sb ³⁺ , but As
If the concentration is high, it is leached in the form of Sb ⁵⁺ . The reason for this is not clear, but if an attempt is made to obtain a leachate with a high As concentration, the S in the leachate obtained by such treatment will be
It is difficult to obtain a leachate with a high b concentration and a high As content and a low Sb content.

Below 100 ° C. in the presence of an oxygen-containing gas,
When the leachate obtained by contacting electrolytically precipitated copper with a sulfuric acid solution is heat-treated at 100 ° C. or higher, or when a Pb compound is added to the leachate and heat-treated at 100 ° C. or higher,
Furthermore, a substance containing Pb is added to the leachate to obtain 10
When heat-treated at 0 ° C or higher, Sb once dissolved in the liquid
^{For 5+} , it is assumed that the reaction according to the following formula proceeds and Sb precipitates. 2H ₃ SbO ₄ → Sb ₂ O ₅ ↓ + 3H ₂ O ··· (3) The precipitate of Sb due to the above reaction is Bi, P in the leachate.
Coprecipitates with a small amount of b, Cu and As. further,
When a Pb compound or a substance containing Pb is added to the leaching solution, the precipitation rate of Sb increases because it coprecipitates with the additive.

The Pb compound used in the present invention is not particularly limited, but is typically PbSO ₄ , PbO, PbCO ₃
Etc. are illustrated. The substance containing Pb is also not particularly limited, but in copper smelting, examples include leaching residues when electrolytically precipitated copper or anode slime is leached with sulfuric acid. The addition amount of the Pb compound or the substance containing Pb is not particularly limited, but if the addition amount is small, the precipitation rate of Sb will be low, and if added in a large amount, the Sb quality in the precipitate will be low and the recovery of Sb will be Not suitable as a raw material. The processing temperature is
There is no particular limitation as long as it is 100 ° C. or higher, but preferably,
The temperature is 160 ° C. to 240 ° C. When the temperature is low, the Sb precipitation rate is low, and when the temperature is high, the heating cost is high. A method of treating electrolytically precipitated copper with a sulfuric acid solution in contact with an oxygen-containing gas at 100 ° C. or higher (the electrolytically precipitated copper leaching residue coexists) is also possible, which is an embodiment of the present invention. . In addition, in this invention, acidic means pH 2.5 or less. When the pH exceeds 2.5, Cu ₃ AsO _{4 and the} like are precipitated, which is not preferable.

According to the present invention, Cu, As are contained, and S
From a sulfuric acid acidic aqueous solution containing b and / or Bi, C
It is possible to secure the concentrations of u and As and remove Sb and / or Bi. Cu and As obtained by the method of the present invention
The contained sulfuric acid acidic aqueous solution is suitable for separation and recovery of Cu and As by a known method.

Examples of the present invention will be described below.

Example 1 Cu 48.2%, As 41.2%, Sb 4.14
%, Bi 0.57%, Pb 2.73%, electrolytically precipitated copper 280
100 g / l sulfuric acid solution (2.8 l) was used, and the temperature was maintained at 60 to 65 ° C., while stirring with a propeller stirrer, air (1 l / min) was blown in for 13 hours for leaching treatment, and then solid-liquid separation was performed. Then, 2.77 l of the leaching solution and a leaching-insoluble residue were obtained. The leachate 0.4 l (Cu 49.9 g / l, T-As 45.
2 g / l, As ⁵⁺ 44.3 g / l, T-Sb 2.73 g / l, S
b ⁵⁺ 2.71 g / l, Bi 0.06 g / l, Pb 0.02 g / l)
Was heated and held at 200 ° C. for 1 hour while being stirred in an autoclave, and after cooling, solid-liquid separation and water washing were performed, and after the heat treatment, the liquid of 0.
I got 4l and the item.

Table 1 shows the quantitative values and the precipitation rate of the liquid after the heat treatment according to Example 1.

[Table 1]

[0019]

[Example 2] PbS was added to 0.4 l of the leachate used in Example 1.
Add 10 g of O ₄ and stir in the autoclave to 2
After heating and holding at 00 ° C. for 1 hour, solid-liquid separation and water washing were carried out after cooling, and 0.4 liter of liquid and a liquid were obtained after heat treatment.

Table 1 shows the quantitative values and the precipitation rate of the solution after the heat treatment according to Example 2.

[0021]

Example 3 PbO was added to 0.4 l of the leachate used in Example 1.
Of 10 g was added, and the mixture was stirred for 200 minutes in an autoclave.
After heating and holding at 1 ° C. for 1 hour, cooling and solid-liquid separation and water washing were performed, and 0.4 liters of liquid and a substance were obtained after the heat treatment.

Table 1 shows the quantitative values and the precipitation rate of the liquid after the heat treatment according to Example 3.

[0023]

Example 4 PbC was added to 0.4 l of the leachate used in Example 1.
Add 10 g of O ₃ and stir in an autoclave for 2
After heating and holding at 00 ° C. for 1 hour, solid-liquid separation and water washing were carried out after cooling, and 0.4 liter of liquid and a liquid were obtained after heat treatment.

Table 1 shows the quantitative values and the precipitation rate of the solution after the heat treatment according to Example 4.

[0025]

Example 5 Cu 48.2%, As 41.2%, Sb 4.14
%, Bi 0.57%, Pb 2.73%, electrolytically precipitated copper 300
0 g was added to 3.0 g of a 100 g / l sulfuric acid solution, the temperature was kept at 60 to 65 ° C., while stirring with a propeller stirrer, 1 l / min of air was blown into the solution for 15 hours for leaching treatment, and then solid-liquid separation was performed. Then, 2.97 l of the leaching solution and a leaching-insoluble residue were obtained. 0.4 l of the exudate (Cu 50.4 g / l, T-As 4
4.7 g / l, As ⁵⁺ 43.5 g / l, T-Sb 2.72 g / l,
Sb ⁵⁺ 2.70 g / l, Bi 0.05 g / l, Pb 0.02 g /
l) the leaching insoluble residue (Cu 4.0%, As 10.7%,
Sb 22.9%, Bi 6.56%, Pb 29.2%) 3 g, and while stirring in an autoclave, 100 ° C, 120
℃, 140 ℃, 160 ℃, 180 ℃, 200 ℃, 240
The temperature was changed to 0 ° C., and the mixture was heat-treated for 1 hour, cooled, and solid-liquid separated and washed with water.

Table 2 shows the quantitative values and the precipitation rate of the liquid after the heat treatment according to Example 5.

[Table 2]

As can be seen from the table, in the embodiment of the present invention,
It is possible to significantly reduce Sb and Bi while maintaining high Cu and As concentrations.

This is obtained by treating the treatment liquid by a known method,
It shows that Sb, Cu having a low Bi content, and As can be recovered.

[0029]

As described above, Sb and / or Sb and / or Bi from the aqueous sulfuric acid solution containing Sb and / or Bi of the present invention is used.
Alternatively, according to the method of removing Bi, the process is simple and difficult control is not required, and S which is difficult to separate by the known method.
b and / or Bi can be removed efficiently.

Claims (4)

[Claims] 1. A sulfuric acid aqueous solution containing Sb and / or Bi is heat-treated at 100 ° C. or higher to obtain Sb and / or Bi from the sulfuric acid aqueous solution containing Sb and / or Bi. Removal method. 2. The Sb and / or Sb and / or Bi from the sulfuric acid aqueous solution containing Sb and / or Bi according to claim 1, wherein a Pb compound is added to the sulfuric acid acidic aqueous solution containing Sb and / or Bi. Or a method of removing Bi. 3. A sulfuric acid aqueous solution containing Sb and / or Bi according to claim 1, wherein a substance containing Pb is added to the sulfuric acid aqueous solution containing Sb and / or Bi. A method for removing Sb and / or Bi. 4. Sb and / or Sb and / or Sb according to claim 3, wherein the sulfuric acid acidic aqueous solution containing Sb and / or Bi is electrolytically precipitated copper leached at a temperature of less than 100 ° C. Alternatively, a method for removing Sb and / or Bi from a sulfuric acid aqueous solution containing Bi.