Carbon-copper-containing powder

Abstract

To provide a carbon-copper-containing powder for the purpose of reusing copper residues as a product while retaining carbon content.SOLUTION: Provided is a carbon-copper-containing powder, comprising C: 5 to 50 mass%, Cu: 15 mass% or more, and MA: 5 to 50 mass%, where MA is one or more selected from the group consisting of Mg, Si, Al, and Fe; the total content of C, Cu, and MA is 80 mass% or more; the average particle size is 50 μm or less; the powder includes porous carbon particles whose surfaces have porous; and the porous contains Cu and MA.SELECTED DRAWING: Figure 1B

Description

[Technical field]

[0001] The present disclosure relates to carbon-copper containing powders. [Background technology]

[0002] During the manufacture of copper products (copper melting process), copper residues may be generated. The copper residues may contain, in addition to copper, carbon derived from charcoal, etc., used to prevent the oxidation of molten copper.

[0003] Currently, in light of resource depletion, recycling of various things is progressing, and recycling of metals that are consumed in large quantities has been carried out for some time. Copper is one of the metals that is consumed in large quantities, and the copper residue mentioned above is usually recycled to recover metallic copper. Summary of the Invention [Problem to be solved by the invention]

[0004] When metallic copper is recovered from copper residue, carbon, which is an unnecessary component, is treated as waste. From the viewpoint of reducing the burden on the environment, the present inventors have investigated reusing the copper residue without treating the carbon contained in the copper residue as waste.

[0005] The present disclosure has been made in view of the above circumstances, and one of its objectives is to provide a carbon-copper containing powder for recycling copper residues as products while still containing carbon. [Means for solving the problem]

[0006] Aspect 1 of the present invention is 1. A carbon-copper containing powder comprising: The composition of the components is C: 5 to 50 mass%; Cu: 15% by mass or more; M is at least one selected from the group consisting of Mg, Si, Al and Fe. A : 5 to 50 mass%; C, Cu and M AThe total content is 80% by mass or more, The average particle size is 50 μm or less, The porous carbon particles have pores on the surface, and Cu and M are contained in the pores. A The carbon-copper containing powder comprises:

[0007] Aspect 2 of the present invention is The composition of the composition is one or more selected from the group consisting of Ca, P, K, Zn, Ni, Mn, Cr, Ti, Cl, Sn, Sr, Zr, V, Rb, S, Mo and Pb. B The carbon-copper-containing powder according to embodiment 1, further comprising more than 0% by mass and not more than 20% by mass of

[0008] Aspect 3 of the present invention is 3. The carbon-copper-containing powder of embodiment 1 or 2, wherein each particle has an inscribed circle diameter of less than 600 μm.

[0009] A fourth aspect of the present invention is The carbon-copper-containing powder according to any one of Aspects 1 to 3 is an antibacterial powder.

[0010] A fifth aspect of the present invention is The carbon-copper-containing powder according to any one of Aspects 1 to 3 is a deodorant powder. Effect of the Invention

[0011] According to an embodiment of the present invention, it is possible to provide a carbon-copper containing powder for recycling copper residue as a product while still containing carbon. [Brief description of the drawings]

[0012] [Figure 1A] FIG. 1A shows a surface SEM image of sample No. 1. [Figure 1B] FIG. 1B shows an enlarged surface SEM image of the porous carbon particles of sample No. 1. [Diagram 2] FIG. 2 shows a surface SEM image of the porous portion of sample No. 1 analyzed by EDX. [Figure 3A] FIG. 3A shows the results of EDX analysis of region A shown in FIG. [Figure 3B] FIG. 3B shows the EDX analysis results for point B shown in FIG. [Figure 3C] FIG. 3C shows the EDX analysis results of point C shown in FIG. [Figure 3D] FIG. 3D shows the EDX analysis results of point D shown in FIG. [Figure 3E] FIG. 3E shows the EDX analysis results of point E shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present inventors have conducted research from various angles in order to realize a carbon-copper containing powder that allows copper residues to be reused as products while still containing carbon. The present inventors have investigated antibacterial applications of copper residues that can be used as products while still containing carbon. However, as a result of the inventors' investigations, it has been found that compositions (mixtures) of copper residues, etc., in which a carbon material such as charcoal is simply mixed with copper, do not have sufficient antibacterial properties. As a result of further intensive research, the present inventors have found that, in addition to carbon and copper, one or more elements selected from the group consisting of Mg, Si, Al, and Fe (hereinafter referred to as "M A The porous carbon particles are adjusted to a predetermined component composition including Cu and M, and the average particle size is controlled to a predetermined value. A It was found that the inclusion of M in the solution provided sufficient antibacterial properties against at least one of Staphylococcus aureus and Escherichia coli. This is because (1) the solution contained M in addition to Cu. A (2) Moisture penetrates into the pores of the porous carbon particles, and the Cu and M contained in the pores are activated. A This is thought to be due to the following: (1) the antibacterial effect was improved by ionization of the pores, and (2) bacteria were captured within the pores with improved antibacterial effect, allowing the antibacterial effect to work more efficiently. In addition, a porous carbon material such as charcoal can adsorb malodorous substances into the pores and have a deodorizing effect. In this embodiment, the pores are filled with Cu and M. A It was expected that the deodorizing effect would be reduced because the copper particles would be filled in to some extent. However, as a result of the study by the present inventors, it was found that the carbon-copper-containing powder according to this embodiment has the same deodorizing effect as porous carbon materials such as charcoal. This shows that the carbon-copper-containing powder according to this embodiment is also useful as a deodorizing powder. However, the technical scope of the present invention is not limited by the above mechanism. The following provides details of each requirement stipulated by the embodiment of the present invention.

[0014] The carbon-copper containing powder according to an embodiment of the present invention has a component composition of C: 5 to 50 mass%; Cu: 15% by mass or more; M is at least one selected from the group consisting of Mg, Si, Al and Fe. A : 5 to 50 mass%; C, Cu and M A The total content is 80% by mass or more, The average particle size is 50 μm or less, The porous carbon particles have pores on the surface, and Cu and M are contained in the pores. A Includes. The powder containing the carbon can be used as a product such as an antibacterial powder. Each requirement will be explained below.

[0015] <1. Ingredient composition> The carbon-copper-containing powder according to the embodiment of the present invention has a composition comprising 5 to 50 mass% of C, 15 mass% or more of Cu, and at least one selected from the group consisting of Mg, Si, Al, and Fe. A : 5 to 50 mass% and containing C, Cu and M A The total content is 80 mass % or more.

[0016] (C:5~50% by mass) C may be an element derived from charcoal or the like used to inhibit oxidation of molten copper. By making the C content 5 to 50 mass % while satisfying other specified requirements, sufficient antibacterial properties can be exhibited. The C content is preferably 10 mass % or more, more preferably 15 mass % or more. The C content is preferably 45 mass % or less, more preferably 40 mass % or less.

[0017] (Cu: 15% by mass or more) Cu is an element that mainly contributes to antibacterial properties. The Cu content is 15% by mass or more to ensure sufficient antibacterial properties. The upper limit of the Cu content is not particularly limited, but may be, for example, 90% by mass or less. In an example of a method for producing a carbon-copper-containing powder according to an embodiment of the present invention described later (a method for performing coarse pulverization, fine pulverization, and coarse particle removal), when normal copper residue (whose Cu content may exceed 50% by mass) is used, the copper components contained in the coarse particles, etc. are removed during the process, and as a result, the Cu content may be 50% by mass or less. Considering the use of this example of the production method, it is preferable to set the Cu content to 50% by mass or less, since it is not necessary to add a Cu-containing material, etc. during the process, and the productivity of the carbon-copper-containing powder according to an embodiment of the present invention is improved.

[0018] (M A :5~50% by mass) M A is at least one selected from the group consisting of Mg, Si, Al and Fe. These elements are usually contained in copper residues and can have a synergistic effect with Cu in terms of antibacterial properties. In order to fully exert this effect, M A The content is 5% by mass or more, preferably 10% by mass or more, and more preferably 15% by mass or more. A Since the effect may be saturated even if M is contained in excess, A The content is set to 50% by mass or less, and preferably 45% by mass or less. M AIt is preferable that the alloy contains at least two selected from the group consisting of Mg, Si, Al and Fe, more preferably at least three selected from the group consisting of Mg, Si, Al and Fe, and even more preferably all of Mg, Si, Al and Fe. This can further improve the synergistic effect with Cu with regard to antibacterial properties. A When these elements are contained, the content of each element alone is preferably 0.1% by mass or more, and more preferably 1.0% by mass or more.

[0019] (C, Cu and M A The total content is 80% by mass or more) The carbon-copper-containing powder according to the embodiment of the present invention contains C, Cu and M, which are active ingredients that contribute to antibacterial properties. A It must contain mainly C, Cu and M. A The total content of C, Cu and M is 80 mass% or more. A The total content is preferably 85% by mass or more, and more preferably 90% by mass or more.

[0020] (Other elements) The carbon-copper-containing powder according to the embodiment of the present invention further comprises one or more M selected from the group consisting of Ca, P, K, Zn, Ni, Mn, Cr, Ti, Cl, Sn, Sr, Zr, V, Rb, S, Mo, and Pb. B M B can be contained without reducing the antibacterial properties as long as the total amount is 20 mass % or less. B may contain a total amount of more than 0 mass%, or 0.1 mass% or more. Usually, copper residue also contains M B Therefore, by allowing the total content to be more than 0 mass% and 20 mass% or less, M B The productivity of the carbon-copper containing powder according to the embodiment of the present invention can be improved, for example by eliminating the need for a process for removing M. B The content of each element alone is preferably 7 mass % or less.

[0021] The carbon-copper containing powder according to the embodiment of the present invention further comprises C, Cu, M A and M.B In the composition of the carbon-copper-containing powder according to one embodiment of the present invention, the balance is C, Cu, M. A and M. B The total amount of the unavoidable impurities may be, for example, 0% by mass or more (or more than 0% by mass) and 1.0% by mass or less.

[0022] <2. Particle size>

[0023] The carbon-copper-containing powder according to the embodiment of the present invention has an average particle size of 50 μm or less. By setting the average particle size within this range, the product is easy to handle and can effectively exhibit antibacterial properties. There is no particular lower limit to the average particle size, but from the viewpoints of cost and ease of handling, it is preferably 1 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more. The average particle size is measured by a laser diffraction method, and the particle size (D50) of the cumulative 50% of the number from the fine particle side of the cumulative particle size distribution is defined as the "average particle size" in this specification. The particle size is the circle equivalent particle size, and the basis of the particle size is the volume. The measurement device that can be used is a laser diffraction type particle size distribution measurement device LA-950 (manufactured by Horiba, Ltd.), etc.

[0024] In the carbon-copper-containing powder according to the embodiment of the present invention, the inscribed circle diameter of each particle is preferably less than 600 μm. By setting the diameter within this range, the product can be handled more easily. In addition, the uniformity is improved, and the variation in antibacterial properties within the powder can be reduced. The lower limit of the inscribed circle diameter is not particularly limited, but may be, for example, 0.1 μm or more. The inscribed circle diameter of each particle can be measured by obtaining a surface SEM image of each particle. Here, the porous carbon particles may contain even finer particles within the pores, but in this specification, "each particle" in the "inscribed circle diameter of each particle" does not include particles within the pores of the porous carbon particles, and the particles within the pores are interpreted as part of the porous carbon particles.

[0025] <3. Porous carbon particles> The carbon-copper containing powder according to an embodiment of the present invention includes porous carbon particles having pores on the surface thereof, and Cu and M are contained within the pores. A This improves antibacterial properties. Cu and M are contained in the pores. A The presence of can be confirmed by analyzing the composition inside the pores with EDX. As a result of EDX analysis, there are parts in the pores where the composition showing the maximum peak is Cu and / or where the composition showing the maximum peak is M. A It is preferable that the composition having the maximum peak is Cu and the composition having the maximum peak is M. A It is more preferable that the antibacterial agent contains both of the above moieties. This can further improve the antibacterial property.

[0026] The shape of the porous carbon particles (particle shape, pore shape, etc.) is not particularly limited, and may be the shape of charcoal, which is usually used to suppress the oxidation of molten copper. Regarding the pore size, the inscribed circle diameter is preferably 0.5 μm or more, more preferably 1 μm or more. In addition, the inscribed circle diameter is preferably 20 μm or less, more preferably 10 μm or less. This allows Cu and M to be contained in the pores. A becomes easier to penetrate.

[0027] The carbon-copper-containing powder according to the embodiment of the present invention may contain other particles as long as it satisfies the above requirements. For example, Cu and / or M may be contained in the pores. A The porous carbon particles may contain no Cu, M A and M. B The metal particles (or alloy particles) may contain at least one selected from the group consisting of:

[0028] <4. Manufacturing method>

[0029] The carbon-copper containing powder according to the embodiment of the present invention is composed of porous carbon particles having pores on the surface, Cu and M. AThe copper residue containing at least M is crushed to an average particle size of 50 μm or less. During this crushing process, Cu and M are trapped in the pores of the porous carbon particles. A is introduced, and a carbon-copper containing powder according to an embodiment of the present invention is obtained. The pulverization method is not particularly limited, and may be performed using a pulverizer such as a disk mill. The pulverization may include two or more steps, such as first roughly pulverizing to a size on the order of a few millimeters using a roll pulverizer or the like, and then finely pulverizing using a pulverizer such as a disk mill. This reduces the load on the pulverizer (fine pulverizer) such as a disk mill, and also allows Cu and M to be trapped in the pores of the porous carbon particles. A It is also preferable to include a coarse particle removal step using a vibrating sieve or the like after pulverization (fine pulverization). This makes it possible to remove coarse particles (e.g., with an inscribed circle diameter of 600 μm or more), making it easier to obtain a carbon-copper-containing powder with an inscribed circle diameter of less than 600 μm. In the above-mentioned manufacturing method, as long as ordinary copper residue is used as the raw material, it is possible to obtain a carbon-copper containing powder that satisfies the composition specified in the embodiment of the present invention without any particular adjustment of the composition.

[0030] The method for producing a carbon-copper-containing powder according to an embodiment of the present invention may include other steps as long as the object of the present disclosure is achieved. For example, as long as the component composition specified in the embodiment of the present invention is satisfied, additional raw materials (copper material, carbon material such as porous carbon particles, M) may be added to increase or decrease the amount of each element as necessary. A The process may include steps of adding ingredients (e.g., ingredients) and / or removing certain components. EXAMPLES

[0031] The following examples are provided to more specifically describe the embodiments of the present invention. The embodiments of the present invention are not limited to the following examples, and may be modified as appropriate within the scope of the above and below-described aims, and all of these are included in the technical scope of the embodiments of the present invention.

[0032] Porous carbon particles with pores on the surface, Cu and M, generated during the copper product manufacturing process (copper melting process) A The copper residue containing at least was collected and dried at 105°C for 24 hours using a dryer. Since the copper residue may also contain coarse objects such as screws, in order to reduce the load on the crusher in the crushing process described below, magnetic coarse objects such as screws were removed using a magnetic separator. The copper residue was then coarsely crushed using a roll crusher so as to pass through a sieve with a mesh size of 2.3 mm. After the coarse crushing, the remaining magnetic coarse objects were removed using a magnetic separator. Then, the copper residue was crushed using a disk mill so as to have an average particle size of 50 μm or less. Specifically, the copper residue was crushed using ethanol as a crushing aid, and after crushing, the particle size distribution was measured using a laser diffraction particle size distribution measuring instrument LA-950 (manufactured by Horiba, Ltd.), and the particle size (D50) of the cumulative 50% of the number from the fine particle side of the cumulative particle size distribution was set as the average particle size, and crushing (fine crushing) was repeated until the average particle size was 50 μm or less. The particle size was the circle equivalent particle size, and the standard for the particle size was volume. Then, to remove coarse particles, the mixture was passed through a vibrating sieve (mesh size 600 μm) and the powder that passed through the sieve was collected. Then, to remove the ethanol, which is a grinding aid, the mixture was dried at 105°C for 24 hours using a dryer to obtain powder sample No. 1. Powder samples No. 2 to 6 were obtained in the same manner as sample No. 1, except that copper residue generated during the manufacture of other copper products was used. The composition analysis results of each sample are shown in Table 1. The average particle size of samples No. 1 to 6 was all within the range of 34 to 36 μm.

[0033] [Table 1]

[0034] The powders of samples No. 1 to 6 were observed with an SEM and analyzed with EDX. As a result, all the powders contained porous carbon particles with pores on the surface, and Cu and M were found to exist within the pores. AThe inscribed circle diameter of each particle was less than 600 μm, and the porous diameter (inscribed circle diameter) was 3 to 8 μm. As an example, FIG. 1A shows a surface SEM image of sample No. 1, and FIG. 1B shows an enlarged surface SEM image of the porous carbon particles of sample No. 1. As shown in FIG. 1A, the diameter of the inscribed circle 1 of the largest particle was 200 μm, and the diameter of the inscribed circle 2 of the smallest particle was 1 μm. In addition, porous carbon particles 3 having pores on the surface were confirmed. The pores of the porous carbon particles shown in FIG. 1B contained even finer particles. FIG. 2 shows a surface SEM image of the porous part of sample No. 1 analyzed by EDX, FIG. 3A shows the EDX analysis results of area A (within the dashed line, about 3 μm × 3 μm) shown in FIG. 2, and FIG. 3B to FIG. 3E show the EDX analysis results of points B to E (about Φ1 μm) shown in FIG. 2, respectively. The EDX measurement equipment used was an SEM (JSM-7100F, manufactured by JEOL Ltd.) and an EDX (JED-2300F, manufactured by JEOL Ltd.), and the accelerating voltage was set to 10 kV. As shown in FIG. 3A, in region A within the porous region, Cu and M A In addition, in the porous region, as shown in FIG. 3B, there is a portion (point B) where the composition showing the maximum peak is Cu, and as shown in FIG. 3C, there is a portion (point C) where the composition showing the maximum peak is M. A It was confirmed that the mixture contained a portion (point C) that was either one of the above (Mg).

[0035] Additionally, for comparison, we prepared sample No. 7, which was commercially available copper powder (manufactured by Hayashi Pure Chemical Industries, Ltd., model number: 03003695, purity: 99.6% or higher), and sample No. 8, which was a mixture of commercially available copper powder and charcoal used to inhibit oxidation in molten copper so that the Cu content was 20 mass%.

[0036] Antibacterial tests were conducted on powder samples No. 1 to 8. The test method was based on JIS Z 2801:2010. Specifically, each powder (specimen) was thinly spread in a petri dish to an area of ​​about 5 cm x about 5 cm, and a test bacteria liquid was inoculated onto the surface. The test bacteria liquid was prepared by inoculating and culturing the test bacteria on a nutrient agar medium (a nutrient source for increasing the number of test bacteria) and using nutrient bouillon (a nutrient source during testing). Two types of test bacteria were used: Staphylococcus aureus and Escherichia coli. Table 2 shows the viable cell counts after 24 hours of culture when samples No. 1 and No. 7 were used as specimens, Table 3 shows the viable cell counts after 24 hours of culture when samples No. 2 to No. 6 were used as specimens, and Table 4 shows the viable cell count after 24 hours of culture when sample No. 8 was used. Note that after 24 hours of culture, the viable cell count of the control sample was 5×10 7 Under the above conditions, samples with a viable cell count of 100 or less were evaluated as exhibiting sufficient antibacterial properties. Furthermore, after 24 hours of incubation, the viable cell count of the control sample was 5×10 7 Under the above conditions, samples with a viable cell count of 10 or less were evaluated as exhibiting good antibacterial properties, and samples with a viable cell count of less than 1 were evaluated as exhibiting even better antibacterial properties.

[0037] [Table 2]

[0038] [Table 3]

[0039] [Table 4]

[0040] The test results in Tables 2 to 4 reveal the following: Samples Nos. 1 to 6 are examples that satisfy all of the requirements of the embodiments of the present invention, and have sufficient antibacterial properties against at least one of Staphylococcus aureus and Escherichia coli, and have equivalent antibacterial properties to the copper powder of sample No. 7 for comparison. Sample No. 8 had insufficient antibacterial properties, although it had the same copper content as Samples Nos. 1 to 6. This is believed to be because it did not satisfy the component composition specified in the embodiment of the present invention, and / or because the crushing step specified in the embodiment of the present invention was not carried out, and therefore components such as Cu were not contained within the pores of the porous carbon particles (charcoal).

[0041] Furthermore, in order to evaluate the deodorizing effect of the carbon-copper containing powder according to this embodiment, the following experiment was carried out. 1g of the charcoal used in sample No. 1, sample No. 7, or sample No. 8 (referred to as sample No. 9) was placed in a 5L gas bag, and 3L of malodorous gas was then poured in, after which the change in malodorous gas concentration over time was measured using a detector tube. As a comparison, the malodorous gas concentration was measured in the same manner as above without putting sample powder in the 5L gas bag (no powder). The malodorous gas was isovaleric acid, hydrogen sulfide, or methyl mercaptan. The results are shown in Tables 5 to 7.

[0042] [Table 5]

[0043] [Table 6]

[0044] [Table 7]

[0045] The test results in Tables 5 to 7 reveal the following: Sample No. 1 is an example that satisfies all of the requirements of the embodiment of the present invention, and had the same deodorizing effect as charcoal (sample No. 9). [Explanation of symbols]

[0046] 1. Inscribed circle of the largest particle 2. Inscribed circle of the smallest particle 3. Porous carbon particles

Claims

1. 1. A carbon-copper containing powder comprising: The composition of the components is C: 5 to 50% by mass; Cu: 15% by mass or more; M is at least one selected from the group consisting of Mg, Si, Al and Fe. Ａ : 5 to 50 mass%; C, Cu and M Ａ The total content is 80% by mass or more, The average particle size is 50 μm or less, The porous carbon particles have pores on the surface, and Cu and M are contained in the pores. Ａ 1. A carbon-copper containing powder comprising:

2. The composition of the alloy is at least one selected from the group consisting of Ca, P, K, Zn, Ni, Mn, Cr, Ti, Cl, Sn, Sr, Zr, V, Rb, S, Mo and Pb. Ｂ The carbon-copper-containing powder according to claim 1, further comprising more than 0 mass% and not more than 20 mass% of

3. 3. The carbon-copper containing powder according to claim 1, wherein the inscribed circle diameter of each particle is less than 600 μm.

4. 3. The carbon-copper-containing powder according to claim 1, which is an antibacterial powder.

5. 3. The carbon-copper-containing powder according to claim 1, which is a deodorizing powder.

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