JP6652268B2 - Refining equipment - Google Patents

Description

The present invention relates to a refining apparatus, and particularly to a method for producing high-purity magnesium.

  Patent Documents 1 and 2 disclose a mixture of a first oxide (for example, magnesium oxide, potassium oxide or calcium oxide) and a second oxide (for example, carbon dioxide or silicon monoxide). Alternatively, a method of desorbing oxygen from the first or second oxide by irradiating a compound with a laser has been proposed.

  Patent Literature 2 also discloses a method of obtaining high-purity silicon by irradiating a mixture of a first oxide and a second oxide at a predetermined ratio or a combination thereof with a laser to obtain high-purity silicon.

Japanese Patent No. 5864659 No. 5546359

  When this is applied to refining of magnesium, when silicon monoxide is used as a reducing agent, the purity of the obtained magnesium is about 25%, and even when silicon is used as a reducing agent, the purity is about 70% at best. In these methods, it is considered at present that the purity is limited. However, in consideration of application to a magnesium battery or the like, a magnesium purity of at least 90% or more is required, and a new method for obtaining high-purity magnesium is required for that purpose.

 Theoretically, when a temperature higher than the boiling point is applied to an oxide by using a laser or the like under a predetermined condition, the bond with oxygen is cut, and the substance bonded to the oxygen is separated. Can be. That is, it is possible to separate a target substance from various oxides, not limited to magnesium. However, it is very difficult to select the predetermined conditions, and it is very difficult to effectively increase the purity of a target substance (hereinafter referred to as a target substance).

  The present inventor has found a method for obtaining high-purity magnesium as a result of research and experiments. Another object of the present invention is to provide a refining apparatus and a method for selectively extracting only a target substance from a target substance and an oxide of the target substance, not only magnesium, to obtain a high-purity target substance. At this time, a laser is used as a heat source, and a high-purity target substance is obtained by optimizing laser irradiation conditions.

That is, the refining device of the present invention
By irradiating the target substance and a mixture or compound of the oxide of the target substance with a laser at a predetermined output that satisfies a temperature condition that is equal to or lower than the boiling point of the oxide and equal to or higher than the boiling point of the target substance. Separating the target substance from the oxide.

  The predetermined output is applied to the oxide and the target substance mixed at a fixed ratio, the laser having a constant wavelength and irradiation time, and irradiating the laser by changing the output of the laser under the temperature condition. The laser output when the purity of the target substance obtained at that time is high may be used.

  The target substance may be magnesium.

  The refining device may include an adhesion medium that deposits the target substance obtained by evaporating by irradiating the laser.

  Further, the attachment medium may be divided into a plurality of sections, and the target substance may be simultaneously deposited on each section.

  Further, the adhesion medium may be removable from the refining device.

  Further, the surface of the attachment medium may be covered with carbon powder, and the attached target substance may be removable from the attachment medium.

  According to the present invention, it is possible to provide a method for obtaining a high-purity target substance from a mixture of various target substances and oxides of the target substance. Further, this method can provide a method for refining magnesium with high purity, and can be used as a fuel for a magnesium battery.

It is a typical side sectional view of the laser refining device of the present invention. (Example 1) FIG. 4 is a graph showing the relationship between the mixing ratio of magnesium oxide and silicon, the magnesium fraction and the silicon fraction [mass% concentration], and energy efficiency [mg / kJ]. FIG. 4 is a diagram showing the relationship between laser output [W] and magnesium purity [mass% concentration]. It is a schematic diagram of the collector of the present invention. (Example 2) FIG. 1 is a schematic perspective configuration diagram of a laser refining device of the present invention. (Example 3)

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the drawings, similar parts are denoted by the same reference numerals.

  FIG. 1 is a schematic side sectional view of a laser refining device 100 according to a first embodiment of the present invention. FIG. 1 shows a processing chamber 101 generally called a chamber. An exhaust pump P is attached to the processing chamber 101, and the inside of the processing chamber 101 is exhausted as needed.

  Note that a gas introduction pipe (not shown) is provided in the processing chamber 101, and a nitrogen gas, an argon gas, a helium gas, a neon gas, an inert gas, or the like can be selectively introduced into the processing chamber 101.

  The processing chamber 101 is provided with a stage 103 on which the container 102 is placed. The container 102 contains a substance to be irradiated with the laser by the laser irradiation device 104. A collector 107 for depositing a substance evaporated by laser irradiation is provided above the container 102.

  In addition, an entrance window 105 for taking in the laser emitted from the laser irradiation device 104 into the processing chamber 101 is provided above the processing chamber 101. The optical path of the laser is provided with a reflecting mirror 106 for changing the optical path so that the laser irradiated from the laser irradiation device 104 can be taken into the processing chamber 101 through the incident window 105.

  As the laser irradiation device 104, for example, a solid laser, a gas laser, or a semiconductor laser irradiation device using an energy source including sunlight, geothermal heat, wind power, or the like of several kW can be used.

  See Japanese Patent No. 5546359, filed and registered by the present inventors, for a refining apparatus 100 of this type, which is incorporated herein by reference.

  In this embodiment, focusing on magnesium, a mixture of magnesium and magnesium oxide is stored in the container 102. The substance contained in the container 102 is not limited to the above, and may be a mixture or compound of any target substance and an oxide of the target substance, such as calcium oxide and calcium, potassium oxide and potassium.

  The laser irradiation device 104 irradiates the mixture of magnesium and magnesium oxide contained in the container 102 with laser. The intensity of the laser at this time is determined as follows. First, since magnesium oxide has a boiling point of about 3873K and magnesium has a boiling point of about 1363K, laser irradiation is performed with a laser output that realizes a temperature range of 1363K to 3873K. By irradiating a laser in this temperature range, magnesium and oxygen in the magnesium oxide are separated, and at the same time, magnesium is ejected from the container 102 as a vapor. The vaporized magnesium is deposited on the surface of the collector 107.

  Next, a method for selecting the optimum value of the laser output for obtaining high-purity magnesium within this temperature range so as to efficiently improve the purity of magnesium obtained on the collector 107 will be described based on experimental results. It is shown below.

  The laser can heat only a very small area, and the temperature of the irradiated area can be arbitrarily realized by adjusting the irradiation intensity, irradiation time, and the like. The present inventor made a sample in which the mixing ratio of magnesium oxide and magnesium was kept constant, irradiated the sample with a laser, measured the purity of magnesium, and conducted an experiment to examine the laser output when the purity was highest. Was. That is the experimental result shown in FIG. In this experiment, a sample was prepared in which the molar ratio of magnesium was 60% and the molar ratio of magnesium oxide was 40% so that the mixture ratio was always constant. ), And irradiated with a semiconductor laser having a wavelength of 808 nm while changing the laser intensity for one second at a time. FIG. 3 shows the relationship between the laser output [W] and the magnesium purity [wt%] (mass% concentration) at this time. When the output of the irradiation laser is changed, the temperature changes, and an optimum temperature is realized. FIG. 3 illustrates this clearly. As the laser output is increased, the purity of magnesium rapidly increases around 950 [W], and the purity further decreases when the laser output is further increased. At a laser output of 950 [W] indicating the highest magnesium purity, although not shown in FIG. 3, the amount of the substance deposited on the collector 107 was 25 mg, and 23.1 mg of this was determined to be magnesium by analysis. It is clear. That is, a purity of 92.4% by weight is obtained. This is 95.3% in molar ratio.

  Thus, the optimum value 950 [W] of the laser output can be obtained. Here, the reason why 950 [W] is optimal in the experimental results depends on the beam diameter of the irradiation laser, the irradiation time, and the like, and does not always reach this value under the experimental conditions in which these parameters are different. However, it can be easily inferred that there is an optimum value of the laser output for each parameter.

  As described above, by selecting the optimum value of the laser output, high-purity magnesium can be obtained. In addition, it can be used as a method for separating a target substance from various oxides other than magnesium.

  Next, a method for improving the purity of magnesium obtained from magnesium oxide as described below using this example will be described.

  First, as a first step, magnesium oxide is mixed or combined with a reducing agent such as silicon monoxide, silicon, carbon, or the like, is contained in a container 102, and is irradiated with a laser by a laser irradiation device 104, whereby magnesium and oxygen are removed. Simultaneously with the separation, the gas is ejected from the container 102 as steam. This vapor is vapor-deposited on the surface of the collector 107 provided on the upper part of the container 102.

  FIG. 2 shows experimental results obtained by examining a substance constituting a substance deposited on the surface of the collector 107 at this time. FIG. 2 shows the mixing ratio when magnesium oxide and silicon are used as a reducing agent on the horizontal axis, and the magnesium fraction and silicon fraction [wt%] (mass% concentration) obtained by reduction at this time are shown on the left. The vertical axis shows the energy efficiency [mg / kJ] on the right vertical axis. As shown in FIG. 2, the mixing ratio of magnesium oxide and silicon affects the reduction efficiency of magnesium. According to FIG. 2, even if the mixing ratio of silicon is low, the ratio of magnesium obtained by reduction is low, and The higher the mixing ratio of silicon, the higher the proportion of silicon. The fact that the mixing ratio of the oxide and its reducing agent affects the reduction efficiency is described in Japanese Patent Publication No. 5546359 cited above. According to FIG. 2, when magnesium oxide: silicon = 1: 0.2-0.3, the proportion of magnesium in the product is high, that is, 60-70%. Analysis shows that most of the constituents other than magnesium in this product are magnesium oxide.

  Next, the products to be deposited on the collector 107 (consisting essentially of magnesium and magnesium oxide as described above) are collected, stored in the container 102, and irradiated again with the laser. The intensity of the laser at this time is within the above-mentioned temperature range, and by irradiating with a predetermined laser output at which the purity of magnesium is highest, magnesium having a higher purity than magnesium obtained from magnesium oxide in the first irradiation is obtained. Can be obtained.

  Here, the collector 107 has a plate-like shape in FIG. 1, but various shapes can be adopted. Further, the collector 107 may be made of any material as long as it satisfies a heat-resistant condition that does not dissolve by the heat of the evaporant from the container 102 to be deposited here. In the present embodiment, a copper plate is used as the collector 107.

  In this manner, high-purity magnesium can be deposited on the collector 107. In a portable charger using a magnesium battery that has been put into practical use, a magnesium plate having a size of 6 cm square and a thickness of 1 mm is used. At this time, the weight of magnesium was 6.3 g. In the experiment of FIG. 3 described above, a laser of 950 [W] was irradiated for 1 second to obtain 23.1 mg of magnesium. Therefore, the irradiation radius of the laser of 8 kW was widened, the area was increased, and the laser output per 1 cm 2 was obtained. , The same temperature can be realized, so that 0.19 g of magnesium can be laminated per second. When this is irradiated for 33 seconds, the weight becomes 6.3 g, and one magnesium plate can be manufactured in 33 seconds. For example, if 30 laser refining apparatuses 100 of the first embodiment are used to irradiate different places and simultaneously perform evaporation, one sheet can be manufactured in one second. The collector 107 can be used as it is as a magnesium electrode by making it removable. However, some contrivance is required to reuse the collector 107. For example, if powder such as carbon is adhered to the surface of the collector 107, only magnesium can be peeled off after vapor deposition.

  FIG. 4 is a perspective configuration diagram schematically showing a collector portion in the refining device of Embodiment 2 of the present invention. FIG. 4 divides the collector 107 in the refining apparatus of the first embodiment into several sections, each of which plays the role of the collector in the first embodiment, and deposits a target substance which is evaporated by laser irradiation. In addition, by making the thickness of the boundary of the partition thin or making a cut so that each partition can be easily separated, it can be used as it is as fuel for the magnesium battery. The number and shape of the collector are arbitrary, and the magnesium plate is formed in the determined shape as described above. The magnesium plate does not need to be cut or otherwise processed. When manufacturing a magnesium plate by a conventional method, it is necessary to perform three steps of producing a material called a billet by casting, rolling it, obtaining a plate, and cutting it into a predetermined shape. According to Example 2, a plate having an arbitrary shape suitable for the collector can be simultaneously formed only by the step of laser irradiation.

  FIG. 5 is a perspective view schematically showing a state in which the collector 107 in the refining apparatus according to the third embodiment of the present invention is divided into several sections to form a sheet, and is fed like a belt conveyor by a plurality of gears 108. It is a block diagram. The collector 107 deposits a target substance, which is evaporated by laser irradiation in each section as a collector, on the collector 107 below the gear 108. The collector 107 moves clockwise in FIG. 5 by the rotation of the gear 108, and at this time, the target substance deposited by the peeling device 109 is peeled and dropped into the container 102. This is repeated when irradiating the laser again. The gear 108 operates by receiving power from a drive unit and a control unit (not shown).

  At this time, by using a plurality of laser irradiation devices and simultaneously irradiating different portions in the container 102, a plurality of target substances can be quickly and uniformly obtained in each section of the collector 107. .

  The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments.

  INDUSTRIAL APPLICATION This invention can be utilized in the field of the refining apparatus using a laser.

REFERENCE SIGNS LIST 100 Refining device 101 Processing chamber 102 Container 103 Stage 104 Laser irradiation device 105 Incident window 106 Reflector 107 Collector 108 Gear 109 Stripper

Claims (5)

By irradiating the target substance and a mixture or compound of the oxide of the target substance with a laser at a predetermined output that satisfies a temperature condition that is equal to or lower than the boiling point of the oxide and equal to or higher than the boiling point of the target substance. A refining apparatus for separating the target substance from the oxide,
Wherein the predetermined output, the oxide of the magnesium and the magnesium mixed a certain percentage, the laser was constant wavelength and irradiation time, the Rukoto varied in the temperature, the highest magnesium purity the for obtaining an optimum value of indicates to laser power, and a laser output adjusting means,
Refining equipment. The refining device includes an adhesion medium that deposits the target substance obtained by evaporation by irradiating the laser.
The refining device according to claim 1, wherein: The adhesion medium is divided into a plurality of sections, and the target substance is simultaneously deposited on each section,
3. The refining device according to claim 2 , wherein: The adhesion medium is removable from the refining device,
The refining device according to claim 2 or 3 , wherein: The adhesion medium has a surface covered with carbon powder, and the attached target substance can be removed from the adhesion medium.
The refining device according to any one of claims 2 to 4 , wherein:

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