Flotation agent and method for recovering arsenic-free copper mineral

Abstract

The present invention provides: a flotation agent which is capable of improving the separation efficiency of an arsenic-free copper mineral from a mixture that contains an arsenic-containing copper mineral and the arsenic-free copper mineral; and a method for recovering an arsenic-free copper mineral with use of the flotation agent. Provided is a flotation agent which comprises a collection agent that is represented by formula (1), and which is used for the purpose of selectively recovering an arsenic–free copper mineral from a mixture that contains an arsenic-containing copper mineral and the arsenic-free copper mineral. (In the formula (1), R1 and R2 are each independently an alkyl group having 1 to 16 carbon atoms, and at least one of R1 and R2 is a branched alkyl group. R1 and R2 may each independently have a ring structure.)

Description

Flotation reagent and method for recovering arsenic-free copper minerals

[0001] The present disclosure relates to flotation agents and methods for recovering arsenic-free copper minerals.

[0002] In Japan, copper concentrate is imported from foreign countries that are so-called mining countries (for example, South American countries such as Chile and Peru), and is smelted domestically to produce copper bullion. Copper ore mined overseas generally contains copper minerals that contain arsenic (hereinafter simply referred to as arsenic-containing copper minerals) and copper minerals that do not contain arsenic (hereinafter simply referred to as arsenic-free copper minerals), but in recent years the arsenic content in copper concentrate has tended to increase.

[0003] Arsenic contained in copper concentrate is distributed to slag, flue dust, etc. during the smelting process, and these are fixed in a stable form and processed at the smelter. However, there are concerns about increased processing costs due to the increased arsenic content and problems such as storage space inside and outside the smelter. For this reason, there is a need for a technology for selectively recovering arsenic-containing copper minerals in the ore-dressing process, which is a preliminary step in the copper smelting process. For example, Patent Document 1 discloses a method for targeting arsenic-containing copper concentrate, in which the copper concentrate is heat-treated at 90 to 120°C, and then the arsenic minerals are floated and separated from the sinking chalcopyrite, bornite, etc.

[0004] However, the method of Patent Document 1 requires equipment and energy for heating a large amount of copper concentrate, which increases costs accordingly.

[0005] Japanese Patent Application Laid-Open No. 2006-239553

[0006] An object of the present disclosure is to provide a flotation agent that can improve the separation efficiency of an arsenic-free copper mineral from a mixture containing an arsenic-containing copper mineral and an arsenic-free copper mineral, and a method for recovering an arsenic-free copper mineral using the flotation agent.

[0007] [1] A flotation agent containing a collector represented by the following formula (1), which is used to selectively recover an arsenic-free copper mineral from a mixture containing an arsenic-containing copper mineral and an arsenic-free copper mineral: (In the formula (1), R １ and R ２are each independently an alkyl group having 1 to 16 carbon atoms, and R １ and R ２ At least one of R is a branched alkyl group. １ and R ２ may each independently have a cyclic structure. １ and R ２ [3] The flotation agent according to the above [1], wherein R is independently an alkyl group having 4 to 8 carbon atoms. １ and R ２ [4] The flotation agent according to the above [1] or [2], wherein R are all alkyl groups having 4 carbon atoms or all alkyl groups having 8 carbon atoms. １ and R ２ [5] The flotation agent according to any one of the above [1] to [3], wherein R is a branched alkyl group. １ and R ２ are each independently an alkyl group having 4 to 8 carbon atoms, and R １ and R ２ [6] The flotation agent according to the above [1], wherein R is a branched alkyl group. １ and R ２ are all branched alkyl groups having 4 carbon atoms or all branched alkyl groups having 8 carbon atoms. [7] The flotation agent according to the above [1], wherein the compound represented by formula (1) is a compound represented by the following formula (2): [8] The flotation agent according to the above [1], wherein the compound represented by formula (1) is a compound represented by the following formula (3): [9] The flotation agent according to any one of [1] to [8] above, wherein the arsenic-containing copper mineral is an arsenic-containing copper mineral containing one or more selected from the group consisting of enargite, luzonite, and arsenite-tetrahedrite.

[10] The flotation agent according to any one of [1] to [9] above, wherein the arsenic-free copper mineral is an arsenic-free copper mineral containing one or more selected from the group consisting of chalcopyrite, bornite, covellite, and chalcocite.

[11] A method for recovering an arsenic-free copper mineral, which selectively recovers an arsenic-free copper mineral from a mixture containing an arsenic-containing copper mineral and an arsenic-free copper mineral, comprising a recovery step of adding a flotation agent containing a collector to a slurry of the mixture to selectively float and beneficiate the arsenic-containing copper mineral, and selectively recovering the arsenic-free copper mineral, wherein the flotation agent is the flotation agent according to any one of [1] to

[10] above.

[0008] According to the present disclosure, it is possible to provide a flotation agent that can improve the separation efficiency of an arsenic-free copper mineral from a mixture containing an arsenic-containing copper mineral and an arsenic-free copper mineral, and a method for recovering an arsenic-free copper mineral using the flotation agent.

[0009] FIG. 1 is a schematic diagram showing a simple flotation tester (Hallimond tube) used in Examples 1 and 2 and Comparative Examples 1 and 2.

[0010] Hereinafter, a detailed description will be given based on an embodiment.

[0011] As a result of extensive research, the inventors have found that the use of a flotation agent containing, as a collector, a sulfide compound in which the alkyl group has a branched structure can improve the efficiency of separation of arsenic-free copper minerals from a mixture containing arsenic-containing copper minerals and arsenic-free copper minerals, and have completed the present disclosure based on this finding.

[0012] First, the flotation agent of the embodiment will be described.

[0013] The flotation agent of the embodiment includes a collector represented by the following formula (1) which is used to selectively recover an arsenic-free copper mineral from a mixture containing an arsenic-containing copper mineral and an arsenic-free copper mineral.

[0014]

[0015] In the above formula (1), R １ and R ２ are each independently an alkyl group having 1 to 16 carbon atoms, and R １ and R ２ At least one of R is a branched alkyl group. １ and R ２ may each independently have a cyclic structure. １ has a cyclic structure when R １ Any two carbon atoms among the carbon atoms constituting the alkyl group of R ２ has a cyclic structure when R ２ This means that any two carbon atoms among the multiple carbon atoms constituting the alkyl group are bonded to each other to form a cyclic structure.

[0016] The collector represented by the formula (1) is R １ and R ２ Since at least one of the groups is a branched alkyl group, the efficiency of separating the arsenic-free copper mineral from a mixture containing the arsenic-containing copper mineral and the arsenic-free copper mineral (hereinafter simply referred to as the efficiency of separating the arsenic-free copper mineral) can be improved.

[0017] In the above formula (1), R １ and R ２ The carbon numbers of R may be the same or different. １ and R ２ are each preferably independently an alkyl group having 4 to 8 carbon atoms, and R １ and R ２ and are more preferably alkyl groups each having 4 carbon atoms or alkyl groups each having 8 carbon atoms.

[0018] In particular, from the viewpoint of further improving the separation efficiency of arsenic-free copper minerals, it is preferable to use a copper ore containing R １ and R ２ Preferably, R is a branched alkyl group. １ and R２ may be the same or different.

[0019] R in the above formula (1) １ and R ２ are both branched alkyl groups, from the viewpoint of improving the separation efficiency of the arsenic-free copper mineral, R １ and R ２ are each preferably independently an alkyl group having 4 to 8 carbon atoms, and R １ and R ２ is more preferably a branched alkyl group having 4 carbon atoms, and among these, the compound represented by the above formula (1) is even more preferably a compound represented by the following formula (2):

[0020]

[0021] In addition, R in the above formula (1) １ and R ２ are both branched alkyl groups, from the viewpoint of improving the separation efficiency of the arsenic-free copper mineral and from the viewpoint of production costs, １ and R ２ is preferably a branched alkyl group having 8 carbon atoms, and among these, the compound represented by the above formula (1) is more preferably a compound represented by the following formula (3):

[0022]

[0023] The amount of the collector represented by the formula (1) added to the mixture containing the arsenic-containing copper mineral and the arsenic-free copper mineral may be 50 g or more, 60 g or more, or 70 g or more per ton of the mixture. When the amount of the collector added is 50 g or more per ton of the mixture, the separation efficiency of the arsenic-free copper mineral can be improved.

[0024] The amount of the collector represented by the formula (1) added may be 2000 g or less, 1500 g or less, or 1300 g or less per ton of the mixture. When the amount of the collector added is 2000 g or less per ton of the mixture, the efficiency of separation of the arsenic-free copper mineral can be improved.

[0025] The amount of the collector added may be 0.25 to 4 times the upper limit of the solubility of the collector in the solution (for example, water).

[0026] The amount of collector added is based on the copper concentrate. In the case of copper ore, the proportion of arsenic-containing copper minerals and arsenic-free copper minerals contained in the copper ore is low, so the amount of collector added can be adjusted appropriately accordingly.

[0027] The flotation agent may further contain various additives such as a suppressor, a foaming agent, etc. in addition to the collector represented by the formula (1). The flotation agent may also be composed solely of the collector represented by the formula (1) without containing the additives.

[0028] The arsenic-containing copper mineral contained in the mixture is a copper mineral containing arsenic. Specifically, it is a copper mineral containing arsenic (As) as a chemical composition. For example, enargite (Cu ３ AsS ４ ), Luzonite (Cu ３ AsS ４ ), Tennantite (Cu ６ [Cu ４ (Fe, Zn) ２ ]As ４ S １３ ), Giraudite (Cu ６ [Cu ４ (Fe, Zn) ２ ]As ４ Se １３ ), Goldfieldite (Cu ６ Cu ４ Te ２ (Sb, As) ４ S １３ ), Argentotennantite, Ag ６ [Cu ４ (Fe, Zn) ２ ]As ４ S １３ Among these, even when the arsenic-containing copper mineral contains one or more selected from the group consisting of enargite, luzonite, and arsenite, the separation efficiency of the arsenic-free copper mineral is good.

[0029] The arsenic-free copper mineral contained in the mixture is a copper mineral that does not contain arsenic. Specifically, it is a copper mineral that does not contain arsenic element in its chemical composition. For example, chalcopyrite (CuFeS ２ ), Bornite, Cu ５ FeS ４ ), Cobellite, CuS, Chalcocite, Cu ２ Even when the arsenic-free copper mineral contains one or more selected from the group consisting of chalcopyrite, bornite, covellite, and chalcocite, the separation efficiency of the arsenic-free copper mineral is good.

[0030] The arsenic-containing copper mineral may contain single-edged particles with the arsenic-free copper mineral. The arsenic-free copper mineral may also contain a trace amount (e.g., 0.1 wt % or less) of single-edged particles with the arsenic-containing copper mineral. The arsenic-free copper mineral may also contain a trace amount (e.g., 0.1 wt % or less) of arsenic as an impurity.

[0031] The mixture containing an arsenic-containing copper mineral and an arsenic-free copper mineral may be a mixture of an arsenic-containing copper mineral and an arsenic-free copper mineral. For example, it may be a mixture of fine particles of an arsenic-containing copper mineral that have been pulverized and atomized and fine particles of an arsenic-free copper mineral that have been pulverized and atomized. It may also be a copper concentrate containing an arsenic-containing copper mineral and an arsenic-free copper mineral, or a copper ore containing an arsenic-containing copper mineral and an arsenic-free copper mineral.

[0032] When the fine particles of arsenic-containing copper mineral and the fine particles of arsenic-free copper mineral contained in the mixture have an average particle size of 10 μm or more, the arsenic-containing copper mineral is more easily adsorbed onto the air bubbles, thereby improving the efficiency of separation of the arsenic-free copper mineral from the mixture.

[0033] Furthermore, the mixing ratio of the arsenic-containing copper mineral and the arsenic-free copper mineral in the mixture is not limited as long as the separation efficiency of the arsenic-free copper mineral is not reduced. For example, the arsenic-containing copper mineral and the arsenic-free copper mineral may be in the same ratio, or the arsenic-containing copper mineral may be in a greater amount than the arsenic-free copper mineral, or the arsenic-containing copper mineral may be in a smaller amount than the arsenic-free copper mineral.

[0034] Next, a method for recovering an arsenic-free copper mineral according to an embodiment will be described.

[0035] A method for recovering an arsenic-free copper mineral according to an embodiment is a method for selectively recovering an arsenic-free copper mineral from a mixture containing an arsenic-containing copper mineral and an arsenic-free copper mineral, and uses the flotation reagent according to the embodiment. The method for recovering an arsenic-free copper mineral includes a recovery step.

[0036] In the recovery step of the method for recovering an arsenic-free copper mineral, a flotation agent containing a collector is added to a slurry of the mixture to selectively float and beneficiate the arsenic-containing copper mineral, thereby selectively recovering the arsenic-free copper mineral. The flotation agent added to the slurry of the mixture is a flotation agent containing the collector represented by formula (1) above. A slurry of the mixture can be produced by adding water to a mixture containing the arsenic-containing copper mineral and the arsenic-free copper mineral.

[0037] The slurry of the mixture to which the flotation agent is added is a fluid in which minerals containing an arsenic-containing copper mineral and an arsenic-free copper mineral (e.g., mineral particles such as arsenic-containing copper mineral particles and arsenic-free copper mineral particles) are suspended in an aqueous solution. The water added to the mixture containing the arsenic-containing copper mineral and the arsenic-free copper mineral is not particularly limited, and may be, for example, distilled water, tap water, or natural water. Furthermore, water obtained by filtering tap water, natural water, or other water through a reverse osmosis membrane (RO membrane) filter (hereinafter simply referred to as RO water) may also be used.

[0038] The amount of water added to the mixture is not particularly limited as long as it can turn the mixture into a slurry, and may be, for example, 2 mL or more and 500 mL or less per 1 g of the mixture.

[0039] Furthermore, the temperature of the slurry of the mixture to which the flotation agent is added is not particularly limited as long as it is a temperature at which the arsenic-containing copper mineral can be floated, and may be, for example, room temperature (approximately 20°C or higher and 25°C or lower).

[0040] In the embodiment of the method for recovering arsenic-free copper mineral, a so-called reverse flotation process is performed in which arsenic-containing copper mineral is floated to the top surface of the slurry mixture and beneficiated, while arsenic-free copper mineral is retained in the slurry mixture and recovered.

[0041] The method for recovering arsenic-free copper minerals involves blowing air or nitrogen into a slurry of the mixture. This separation method utilizes the fact that among the mineral particles in the slurry, hydrophobic particles easily adhere to the air bubbles and float to the surface, while hydrophilic particles do not easily adhere to the air bubbles and remain in the slurry.

[0042] The collector represented by formula (1) has a site that selectively adsorbs to the arsenic-containing copper mineral compared to the arsenic-free copper mineral, and a hydrophobic site that easily adheres to the air bubbles, and therefore the collector represented by formula (1) selectively causes the arsenic-containing copper mineral (particles) to adhere to the air bubbles and float to the top surface of the slurry. １ and R ２ Since at least one of the groups is a branched alkyl group, i.e., the carbon chain is branched, the collector represented by formula (1) can more efficiently attach arsenic-containing copper minerals to air bubbles and increase the amount of arsenic-containing copper minerals that float. As a result, the froth becomes a high-arsenic copper concentrate in which arsenic is concentrated. Thus, the arsenic-free copper minerals are concentrated in the sinking ore (tailing), and the sinking ore becomes a low-arsenic copper concentrate in which arsenic is reduced.

[0043] The float contains a large amount of arsenic-containing copper minerals. The float may contain not only arsenic-containing copper minerals but also other minerals, impurities, small amounts of arsenic-free copper minerals, etc. On the other hand, the sink contains a large amount of arsenic-free copper minerals. The sink may contain not only arsenic-free copper minerals but also other minerals, impurities, small amounts of arsenic-containing copper minerals, etc.

[0044] In this way, by adding a flotation agent containing the collector represented by the above formula (1) to the slurry of the mixture, selectively flotating and beneficiating the arsenic-containing copper mineral, and selectively recovering the arsenic-free copper mineral that has precipitated in the slurry of the mixture, a concentrate containing a large amount of arsenic-free copper mineral can be obtained from the mixture of arsenic-containing copper mineral and arsenic-free copper mineral. In this way, copper mineral with a low arsenic content or no arsenic can be efficiently recovered from the mixture of arsenic-containing copper mineral and arsenic-free copper mineral.

[0045] According to the embodiment described above, by using a flotation reagent containing the collector represented by formula (1), it is possible to improve the efficiency of separating the arsenic-free copper mineral from a mixture containing the arsenic-containing copper mineral and the arsenic-free copper mineral.

[0046] Although the embodiments have been described above, the present disclosure is not limited to the above embodiments, but includes all aspects encompassed by the concept of the present disclosure and the scope of the claims, and can be modified in various ways within the scope of the present disclosure.

[0047] Next, examples and comparative examples will be described, but the present disclosure is not limited to these examples.

[0048] Example 1 An arsenic-containing copper mineral and an arsenic-free copper mineral were used as mineral specimens for study. Specifically, as an arsenic-containing copper mineral, a mineral specimen named arsenoptite was set as mineral specimen 1, and as an arsenic-free copper mineral, a mineral specimen named chalcopyrite was set as mineral specimen 2. Each mineral specimen was pulverized using a FRITSCH disc mill, and the specimens that were sieved to a 75 μm sieve were used as test samples.

[0049] The quality of each test sample was analyzed by measuring the concentration of each element using an electron probe microanalyzer JXA-8500F manufactured by JEOL Ltd. The results for Mineral Sample 1 are shown in Table 1, and the results for Mineral Sample 2 are shown in Table 2.

[0050]

[0051]

[0052] The compound of formula (2) was used as a collector, and the collector was dispersed in pure water to prepare an aqueous solution containing the compound of formula (2) (hereinafter simply referred to as the aqueous solution of formula (2)). 5 g of mineral specimen 1 (arsenic-containing copper mineral) and pure water were added to a beaker, and the mineral specimen 1 and pure water were stirred for 5 minutes. Next, the aqueous solution of formula (2) was further added to the beaker so that the compound of formula (2) was 100 g per ton of mineral specimen 1, and the solution in the beaker was stirred for 3 minutes. Next, 1.0 mL of a 0.2 wt % solution of methyl isobutyl carbinol (MIBC) was added as a general-purpose foaming agent, and the mixture was stirred for 2 minutes. The resulting slurry 10, which was then allowed to stand for 3 minutes, was then placed in a simple flotation tester 1 (Hallimond tube) shown in Figure 1.

[0053] Next, nitrogen 20 was introduced into the slurry 10 from below the tube 2 constituting the simple flotation tester 1 through the plug 4, generating bubbles 11, and separation by flotation was carried out for 10 minutes. Specifically, most of the arsenic-containing copper mineral particles, which are highly hydrophobic particles 12, adhered to the bubbles 11 and floated up, and the bubbles 11 burst at the top and settled and accumulated in the tube 3 connected to the tube 2 (float A, froth). On the other hand, the particles that did not adhere to the bubbles 11 remained in the tube 2 (tailing B, tailings).

[0054] Then, the amount of float A relative to the total amount of mineral sample 1 charged into simple flotation tester 1 was calculated as the flotation rate of mineral sample 1.

[0055] Next, the same procedure was repeated except that Mineral Sample 1 was replaced with Mineral Sample 2 (arsenic-free copper mineral), and the amount of float A relative to the total amount of Mineral Sample 2 charged into the simple flotation tester 1 was calculated as the float rate of Mineral Sample 2. Then, the separation efficiency (float rate of Mineral Sample 1 / float rate of Mineral Sample 2) was calculated.

[0056] The above-described measurement of separation efficiency was carried out twice (N=2). The two obtained separation efficiency values ​​were then averaged to obtain the separation efficiency of Example 1.

[0057] Example 2 The separation efficiency was determined in the same manner as in Example 1, except that the chemical formula (2) was replaced with the chemical formula (3) above.

[0058] Comparative Example 1 Separation efficiency was determined in the same manner as in Example 1, except that the chemical formula (2) was replaced with the chemical formula (4) below.

[0059]

[0060] Comparative Example 2 Separation efficiency was determined in the same manner as in Example 1, except that the chemical formula (2) was replaced with potassium amyl xanthate (PAX, chemical formula (5) below).

[0061]

[0062] The results of the separation efficiency obtained in Examples 1 and 2 and Comparative Examples 1 and 2 are shown in Table 3. The greater the separation efficiency, that is, the higher the float rate of Mineral Sample 1 and the lower the float rate of Mineral Sample 2, the more preferable it is.

[0063]

[0064] As shown in Table 3, in the above tests using mineral specimens, Example 1 used a flotation agent containing a collector represented by formula (2), and Example 2 used a flotation agent containing a collector represented by formula (3). This confirmed that the separation efficiency of arsenic-free copper mineral from a mixture containing arsenic-containing copper mineral and arsenic-free copper mineral was higher than in Comparative Examples 1 and 2, which used a flotation agent containing a collector represented by formula (4) or a collector represented by formula (5).

[0065] Example 3 An arsenic-containing copper ore was used as an ore sample. The arsenic-containing copper ore was pulverized using a ball mill, and a sample in which 80% of the undersize distribution was 75 μm was used as a test sample.

[0066] The quality analysis of the test sample was performed according to the following analytical flow. First, the weight of the test sample was measured, followed by microwave heating and acid dissolution, and the solution was filled up to a constant volume to obtain an analysis sample solution. Next, the analysis sample solution was subjected to ICP analysis using an ICP-OES 5110 manufactured by Agilent Technologies, and the element concentrations in the solution were quantitatively analyzed. Specifically, the solution volume after filling up was multiplied by the solution concentration of each component element analyzed by ICP, and the result was divided by the weight of the acid-dissolved sample to obtain the element quality (wt%). The quality analysis results of the arsenic-containing copper ore, which was the raw material for the test sample, are shown in Table 4.

[0067]

[0068] 250 g of the test sample and 750 mL of pure water were charged into a 1 L agitator flotation machine, and the pH of the slurry of the pure water and test sample was adjusted to 10.5 with 1 mol / L aqueous sodium hydroxide solution and stirred for 5 minutes.

[0069] Next, the compound of formula (3) was added to the slurry in an amount of 0.25 mol per ton of test sample, and the slurry was stirred for 3 minutes. Next, methyl isobutyl carbinol (MIBC), a general-purpose foaming agent, was added to the slurry in an amount of 10 g per ton of test sample, and the slurry was stirred for 0.5 minutes.

[0070] Next, air was introduced into the Agitair flotation machine to generate bubbles, and separation by flotation treatment was carried out for 1 minute. The sample that adhered to the bubbles was collected as float, and the sample that did not adhere to the bubbles and remained in the slurry was collected as sink. The quality of the collected samples was analyzed, and the recovery rate of arsenic-containing copper mineral was calculated from the following formula (A), the recovery rate of arsenic-free copper mineral was calculated from the following formula (C), and the separation efficiency was calculated from the following formula (D). In addition, the weight of copper derived from the arsenic-containing copper mineral was calculated from the following formula (B).

[0071]

[0072] Comparative Example 3 The recovery rate of the arsenic-containing copper mineral, the recovery rate of the arsenic-free copper mineral, and the separation efficiency were determined in the same manner as in Example 3, except that the compound of formula (3) was replaced with the compound of formula (4) as the collector.

[0073] Table 5 shows the results of the recovery rate and separation efficiency obtained in Example 3 and Comparative Example 3. It is preferable that the recovery rate and separation efficiency of the arsenic-containing copper mineral are high.

[0074]

[0075] As shown in Table 5, in the above test using the ore sample, it was confirmed that Example 3, which used a flotation agent containing the collector represented by formula (3), had a higher separation efficiency than Comparative Example 3, which used a flotation agent containing the collector represented by formula (4).

[0076] 1 Simple flotation tester 2, 3 Tube 4 Plug 10 Slurry 11 Air bubbles 12 Highly hydrophobic particles 20 Nitrogen or air A Float B Tailings

Claims

1. A flotation agent containing a collector represented by the following formula (1) and used for selectively recovering arsenic-free copper minerals from a mixture containing arsenic-containing copper minerals and arsenic-free copper minerals. (In the above formula (1), R １ and R ２ are each independently an alkyl group having 1 to 16 carbon atoms, and at least one of R １ and R ２ is a branched alkyl group. R １ and R ２ may each independently have a cyclic structure.) 2. R １ and R ２ are each independently an alkyl group having 4 to 8 carbon atoms, the flotation agent according to claim 1.

3. R １ and R ２ The flotation agent according to claim 1, wherein both are alkyl groups having 4 carbon atoms or both are alkyl groups having 8 carbon atoms.

4. R １ and R ２ The flotation agent according to claim 1, wherein both are branched alkyl groups.

5. R １ and R ２ are each independently an alkyl group having 4 to 8 carbon atoms, and R １ and R ２ are both branched alkyl groups. The flotation agent according to claim 1.

6. R １ and R ２ are both branched alkyl groups having 4 carbon atoms or both branched alkyl groups having 8 carbon atoms, the flotation agent according to claim 1.

7. The flotation agent according to claim 1, wherein the compound represented by the formula (1) is a compound represented by the following formula (2).

8. The flotation agent according to claim 1, wherein the compound represented by the formula (1) is a compound represented by the following formula (3).

9. The arsenic-containing copper mineral is an arsenic-containing copper mineral containing at least one selected from the group consisting of digenite, luzonite, and enargite, and the flotation agent according to claim 1.

10. The arsenic-free copper mineral is an arsenic-free copper mineral containing at least one selected from the group consisting of chalcopyrite, bornite, covellite, and chalcocite, and the flotation agent according to claim 1.

11. A method for recovering an arsenic-free copper mineral by selectively recovering the arsenic-free copper mineral from a mixture containing an arsenic-containing copper mineral and an arsenic-free copper mineral, comprising: adding a flotation agent containing a collector to a slurry of the mixture to selectively float and beneficiate the arsenic-containing copper mineral, and having a recovery step of selectively recovering the arsenic-free copper mineral, wherein the flotation agent is the flotation agent according to any one of claims 1 to 10.

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