JP2008106346A - Method for producing titanium based hydrogen storage alloy, and production equipment for titanium based hydrogen storage alloy - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a titanium based hydrogen storage alloy with which burning-synthesizing at high temperature is made possible, and further, the cost of a titanium based hydrogen storage alloy can be reduced, and to provide production equipment for a titanium based hydrogen storage alloy. <P>SOLUTION: A sample S composed of raw material powder essentially composed of titanium is mounted on a horizontal crucible 11 so as to be stored in a pressure vessel 21, and the inside of the pressure vessel 21 is made a gaseous hydrogen atmosphere of <0.9 MPa. The sample S is uniformly heated using a heater (uniform heating means) 14 or a part of the sample S is locally heated using an ignition line (local heating means) 12, thus the titanium based hydrogen storage alloy is burnt and synthesized. Since the pressure in the gaseous hydrogen atmosphere is controlled to <0.9 MPa, durability of the pressure vessel 21 is reduced, thus the production device is made inexpensive, and the cost of the titanium based hydrogen storage alloy can be reduced. Further, since the production device can be composed of an internal heating system, the burning-synthesizing of the titanium based hydrogen storage alloy can be performed at temperature higher than the conventional case. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a titanium base hydrogen storage alloy manufacturing method and a titanium base hydrogen storage alloy manufacturing apparatus capable of manufacturing a titanium base hydrogen storage alloy at low cost and low energy by combustion synthesis.

  In order to suppress the consumption of fossil fuel and promote the use of hydrogen as a fuel, hydrogen storage means for storing, transporting and supplying hydrogen is necessary. In particular, inexpensive and high-performance hydrogen storage alloys are indispensable for various hydrogen-related equipment such as automobile hydrogen tanks, heat pumps, and hydrogen purification, and their development is regarded as important.

  As a conventional industrial method for producing a hydrogen storage alloy, a melting method for producing a hydrogen storage alloy by dissolving a raw metal is mainly used. However, in the melting method, it is difficult to handle raw materials with greatly different vapor pressures, and volatile metals cause evaporation loss, so that it is difficult to accurately control the alloy composition. In addition, hydrogen storage alloy ingots manufactured by the melting method do not store hydrogen immediately after manufacturing due to surface poisoning due to oxygen and moisture in the atmosphere, and can reduce the poisoned surface and store hydrogen. In order to achieve this, it is necessary to repeat the “activation process” of applying and suctioning high-pressure hydrogen 10 to 20 times or more after pulverizing and heating the produced hydrogen storage alloy. As a result of the activation treatment, there is a problem that the energy cost for producing the hydrogen storage alloy increases. Further, even when the activation treatment is performed, it is difficult to completely remove the surface poisoning of the hydrogen storage alloy, so that there is a problem that the hydrogen storage ability of the hydrogen storage alloy cannot be fully utilized.

As techniques for solving these problems, Patent Literature 1 and Patent Literature 2 disclose a combustion synthesis method in which a hydrogen storage alloy is synthesized by combustion. In the combustion synthesis method, utilizing the fact that the reaction in which the hydrogen storage alloy is synthesized in a hydrogen atmosphere is a self-heating reaction, the raw material powder is heated in high-pressure hydrogen to synthesize the hydrogen storage alloy in a single heat treatment. In addition, the hydrogen storage alloy can be hydrogenated. Since the hydrogen storage alloy synthesized by the combustion synthesis method has already been hydrogenated, the contained hydrogen suppresses surface oxidation, and the activation treatment becomes unnecessary. Therefore, it is possible to obtain a hydrogen storage alloy that is low in energy cost and that can fully utilize the hydrogen storage capacity.
JP 2000-233906 A JP 2003-193166 A

  The technologies disclosed in Patent Document 1 and Patent Document 2 are mainly intended for Mg hydrogen storage alloys mainly composed of Mg, and the calorific value in the synthesis reaction used for combustion synthesis is relatively small, and high purity. In order to synthesize a hydrogen storage alloy, a high hydrogen pressure of 10 atm or more was required. When mass-producing hydrogen storage alloys using a hydrogen pressure of 10 atmospheres or more, it is difficult to mass-produce products while ensuring safety and complying with laws and regulations. In addition, the manufacturing equipment for combustion synthesis of hydrogen storage alloys in a high-pressure hydrogen atmosphere of 10 atmospheres or higher is heavier in order to ensure pressure resistance, and the inside is an expensive structural material with high pressure resistance, heat resistance, and corrosion resistance. Is necessary, and there is a problem that the cost is high. Furthermore, in this manufacturing apparatus, the heating apparatus must be an external heating type installed outside the pressure vessel. Therefore, the response of the temperature operation is slow, and if the structure is strengthened to improve the pressure resistance and heat resistance capacity, the heating apparatus is heated. Since the capacity is reduced, there is a limit to the pressure resistance and heat resistance. Therefore, the heating temperature in the combustion synthesis of the hydrogen storage alloy has an upper limit of about 600 ° C., and there is a problem that it is difficult to apply it to a system that requires a heating temperature exceeding this temperature.

  The present invention has been made in view of such circumstances. The object of the present invention is to perform combustion synthesis at a high temperature by burning and synthesizing a hydrogen storage alloy under a lower pressure hydrogen atmosphere. It is another object of the present invention to provide a titanium base hydrogen storage alloy manufacturing method and a titanium base hydrogen storage alloy manufacturing apparatus capable of reducing the cost of the titanium base hydrogen storage alloy.

  A method for producing a titanium-based hydrogen storage alloy according to the first aspect of the present invention comprises heating a raw material powder mainly composed of titanium substantially uniformly in a hydrogen gas atmosphere of less than 0.9 MPa, thereby producing a titanium-based hydrogen storage alloy. It is characterized by manufacturing.

  The method for producing a titanium-based hydrogen storage alloy according to the second invention is characterized in that hydrogen gas is supplied as the hydrogen gas decreases in the hydrogen gas atmosphere.

  According to a third aspect of the present invention, there is provided a method for producing a titanium-based hydrogen storage alloy in which a raw material powder mainly composed of titanium is enclosed in a hydrogen gas atmosphere of less than 0.9 MPa, and a part of the raw material powder reacts to form titanium. A part of the raw material powder is locally heated to a temperature necessary for a synthesis reaction to synthesize a base hydrogen storage alloy to occur.

  A titanium-based hydrogen storage alloy manufacturing method according to a fourth aspect of the invention is characterized in that the raw material powder is dispersed in a substantially horizontal plane.

  A method for producing a titanium-based hydrogen storage alloy according to the fifth invention is characterized in that the raw material powder is produced by mechanically pulverizing a raw material mainly composed of titanium in an inert gas or hydrogen gas. .

  In the method for producing a titanium-based hydrogen storage alloy according to the sixth invention, the raw material powder is made of Cr, Fe, Mg, V, Mn, Zr, Ni, Y, Pr, Nd, Sm, Dy, La, other than titanium. It contains at least one element among Ce, Al, O, C, and Co.

  An apparatus for producing a titanium-based hydrogen storage alloy according to a seventh aspect of the present invention provides a horizontal crucible on which raw material powder containing titanium as a main component is placed, and the raw material powder placed on the horizontal crucible is substantially uniform. Uniform heating means for heating, a pressure vessel accommodating the horizontal crucible and the uniform heating means therein, filling the pressure vessel with hydrogen gas, and controlling the pressure of the hydrogen gas in the pressure vessel to less than 0.9 MPa And means for performing.

  An apparatus for producing a titanium-based hydrogen storage alloy according to an eighth aspect of the present invention provides a horizontal crucible for placing a raw material powder mainly composed of titanium, and a part of the raw material powder placed in the horizontal crucible locally. A local heating unit that heats the horizontal crucible and a pressure vessel that encloses the local heating unit in a hydrogen gas atmosphere of less than 0.9 MPa, and the local heating unit includes the raw material powder in the hydrogen gas atmosphere. It is configured to be heated to a temperature necessary for a synthesis reaction in which a part of the body reacts to synthesize a titanium-based hydrogen storage alloy.

  In the first and seventh inventions, titanium and hydrogen react with each other by the combustion synthesis in which the raw material powder containing titanium as a main component is uniformly heated in a hydrogen gas atmosphere of less than 0.9 MPa. Can be manufactured. Since the pressure in the hydrogen gas atmosphere could be less than 0.9 MPa, the durability of the pressure vessel that stores the raw material powder can be lowered. Further, the titanium-based hydrogen storage alloy manufacturing apparatus can have an internal heating type configuration in which a uniform heating means for heating the raw material powder is provided in the pressure vessel.

  In the second aspect of the invention, by supplying the hydrogen gas as the hydrogen gas in the hydrogen gas atmosphere decreases, the decrease in the hydrogen gas due to the production of the titanium-based hydrogen storage alloy is compensated.

  In the third and eighth inventions, titanium and hydrogen react with each other by locally heating a part of the raw material powder mainly composed of titanium in a hydrogen gas atmosphere of less than 0.9 MPa. A synthesis reaction in which the hydrogen storage alloy is synthesized by combustion occurs, and a synthesis reaction occurs continuously in the raw material powder by the reaction heat of the synthesis reaction, and a titanium-based hydrogen storage alloy is synthesized.

  In the fourth invention, the raw material powder in the hydrogen gas atmosphere is dispersed in a horizontal plane without forming a green compact, so that hydrogen gas can easily diffuse in the raw material powder in the hydrogen gas atmosphere. .

  In the fifth invention, the raw material reaction interface is increased by mechanically grinding the raw material to produce the raw material powder.

  In the sixth invention, in addition to titanium, at least one of Cr, Fe, Mg, V, Mn, Zr, Ni, Y, Pr, Nd, Sm, Dy, La, Ce, Al, O, C, Co A titanium-based hydrogen storage alloy can be produced from the raw material powder containing the element by the same method.

  In the first and seventh inventions, since the pressure of the hydrogen gas atmosphere could be less than 0.9 MPa, it is easier to ensure safety and comply with laws and regulations than in the past, and mass production of titanium-based hydrogen storage alloys is more possible. It becomes easy. In addition, the durability of the pressure vessel that stores the raw material powder can be reduced, and a titanium-based hydrogen storage alloy manufacturing apparatus can be manufactured at a lower cost than before. Therefore, the cost of the titanium-based hydrogen storage alloy to be manufactured can be reduced. In addition, the titanium-based hydrogen storage alloy manufacturing equipment has an internal heating type structure that enables rapid temperature control and manufactures titanium-based hydrogen storage alloys that require temperatures higher than the conventional limits. Therefore, it is possible to manufacture other types of titanium-based hydrogen storage alloys depending on the application.

  In the second invention, by supplying the hydrogen gas as the hydrogen gas in the hydrogen gas atmosphere decreases, the reduction of the hydrogen gas due to the formation of the titanium-based hydrogen storage alloy is compensated for, and the titanium-based hydrogen storage alloy Can be efficiently manufactured.

  In the third and eighth inventions, a titanium-based hydrogen storage alloy is produced by locally heating a part of the raw material powder mainly composed of titanium in a hydrogen gas atmosphere of less than 0.9 MPa. Therefore, the input energy for producing the titanium-based hydrogen storage alloy is small, and the energy cost of the titanium-based hydrogen storage alloy can be reduced.

  In the fourth invention, when the titanium-based hydrogen storage alloy is manufactured, the hydrogen gas can be easily diffused in the raw material powder in the hydrogen gas atmosphere. This facilitates the reaction in which the titanium-based hydrogen storage alloy is combusted and synthesized. Therefore, a titanium-based hydrogen storage alloy can be produced efficiently.

  In the fifth invention, the raw material is mechanically pulverized to produce the raw material powder, whereby the reaction interface of the raw material is increased and the reaction for synthesizing the titanium-based hydrogen storage alloy is facilitated. It becomes possible to manufacture the base hydrogen storage alloy efficiently.

  In the sixth invention, in addition to titanium, elements such as Cr, Fe, Mg, V, Mn, Zr, Ni, Y, Pr, Nd, Sm, Dy, La, Ce, Al, O, C, and Co are used. Various titanium-based hydrogen storage alloys containing these elements can be produced from the contained raw material powder. Therefore, the present invention has excellent effects, such as being able to produce a titanium-based hydrogen storage alloy containing components according to the application.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
FIG. 1 is a schematic cross-sectional view showing the configuration of the titanium-based hydrogen storage alloy manufacturing apparatus of the present invention. In the titanium-based hydrogen storage alloy manufacturing apparatus, the horizontal crucible 11 formed in a dish shape is surrounded by a heat insulating material 22 and further stored in a pressure vessel 21. The horizontal crucible 11 is configured such that the sample S, which is a raw material powder mainly composed of titanium, can be dispersed and placed in a horizontal plane. A heater (uniform heating means) 14 for uniformly heating the horizontal crucible 11 is disposed on the bottom and side surfaces of the horizontal crucible 11. A carbon heater was used as the heater 14. The heat insulating material 22 is formed in a hollow rectangular parallelepiped shape, houses the horizontal crucible 11 and the heater 14 therein, and covers the entire periphery of the horizontal crucible 11 and the heater 14.

  The titanium-based hydrogen storage alloy manufacturing apparatus includes a plurality of thermocouples 13, 13,... For measuring the temperature around the horizontal crucible 11 and the sample S. The heater 14 and the thermocouples 13, 13,... Are connected to a temperature control unit 41 outside the pressure vessel 21. The temperature control unit 41 is configured to measure the temperature around the horizontal crucible 11 and the temperature of the sample S using the thermocouples 13, 13,... And supply the current to the heater 14 to heat the sample S. ing. The temperature control unit 41 can control the temperature of the sample S by controlling the current to the heater 14 by PID control while measuring the temperature around the horizontal crucible 11 and the temperature of the sample S.

  Furthermore, the titanium-based hydrogen storage alloy manufacturing apparatus locally heats a part of the sample to a temperature necessary for a synthesis reaction in which a part of the sample S reacts to synthesize a titanium-based hydrogen storage alloy. An ignition wire (local heating means) 12 for performing an operation (hereinafter referred to as ignition) is provided. FIG. 2 is a schematic perspective view showing the horizontal crucible 11, the sample S, and the ignition wire 12. The ignition wire 12 is a heating wire that generates heat when current is conducted, and is placed in contact with the sample S placed on the horizontal crucible 11. When the ignition wire 12 generates heat, a part of the sample S in contact with the ignition wire 12 is heated. The ignition wire 12 is connected to a current supply unit 42 outside the pressure vessel 21, and the current supply unit 42 is configured to supply a predetermined current to the ignition wire 12.

  The pressure vessel 21 is configured to withstand an internal pressure of at least 1 MPa or less. The pressure vessel 21 is provided with a gas supply pipe 31 for supplying hydrogen gas to the inside and a gas discharge pipe 32 for discharging hydrogen gas from the inside. The gas supply pipe 31 and the gas discharge pipe 32 are connected to a hydrogen gas control unit 30 outside the pressure vessel 21 by piping. Further, the pressure vessel 21 is provided with a pressure gauge 33 for measuring the internal pressure, and the pressure gauge 33 is connected to the hydrogen gas control unit 30. The hydrogen gas control unit 30 includes a measuring device that measures the pressure in the pressure vessel 21 using a vacuum pump, a hydrogen gas cylinder, a pressure gauge 33, and a pressure regulator. The hydrogen gas control unit 30 supplies the hydrogen gas from the gas supply pipe 31 into the pressure vessel 21, discharges the hydrogen gas from the gas discharge tube 32, and adjusts the supply amount and the discharge amount of the hydrogen gas to adjust the pressure vessel 21. Control the hydrogen gas pressure inside.

  Next, based on the Example performed using the manufacturing apparatus of the titanium base hydrogen storage alloy which consists of the above structure, the manufacturing method of the titanium base hydrogen storage alloy of this invention is demonstrated. In the present invention, as a method for producing a titanium-based hydrogen storage alloy from the sample S, which is a raw material powder containing titanium as a main component, a method for combusting and synthesizing the titanium-based hydrogen storage alloy by uniformly heating the sample S; There is a method of combusting and synthesizing a titanium-based hydrogen storage alloy by igniting the sample S.

  First, as a method for producing a titanium-based hydrogen storage alloy of the present invention, a method for combusting and synthesizing a titanium-based hydrogen storage alloy by heating the sample S uniformly will be described with reference to examples. A sample S made of titanium powder having a particle size of 1 mm or less and a purity of about 99% was placed on the horizontal crucible 11 and a titanium-based hydrogen storage alloy manufacturing apparatus shown in FIG. 1 was set. The sample S is sprayed without being compacted and placed on the horizontal crucible 11 so that hydrogen gas can easily diffuse in the sample S in a hydrogen gas atmosphere. The mass of the sample S was 500 g. Hydrogen gas was supplied into the pressure vessel 21 from the gas supply pipe 31. The hydrogen gas penetrates into the heat insulating material 22 and the pressure vessel 21 is in a pressurized hydrogen gas atmosphere.

  FIG. 3 is a characteristic diagram showing temperature and pressure histories in an example in which a titanium-based hydrogen storage alloy was combusted and synthesized by heating the sample S uniformly. In the figure, the horizontal axis indicates time, and the vertical axis indicates temperature and pressure. In FIG. 3, the temperature around the horizontal crucible 11 is indicated by diamonds, the pressure of the hydrogen gas in the pressure vessel 21 is indicated by triangles, and the sample temperature is indicated by squares. In the example, the supply of the hydrogen gas was stopped in a state where the pressure of the hydrogen gas was 0.5 MPa, and heating was started by the heater 14. Since the heater 14 is disposed on the bottom and side surfaces of the horizontal crucible 11, the entire sample S can be heated at a substantially uniform temperature. As the temperature around the horizontal crucible 11 rises, the sample temperature and the hydrogen gas pressure also rise. When the temperature around the horizontal crucible 11 reaches 600 ° C., the sample temperature rises rapidly and the hydrogen gas pressure falls. . The sample temperature reached a maximum of 900 ° C. At this stage, the temperature rise by the heater 14 was stopped, and the temperature around the horizontal crucible 11 was maintained at about 600 ° C. After the sample temperature dropped to about 700 ° C., hydrogen gas was additionally supplied from the gas supply pipe 31 a plurality of times. The timing at which hydrogen gas is supplied is indicated by arrows in FIG. After 2 hours from the start of heating, it was confirmed that the pressure of hydrogen gas was not reduced, and the operation of the production apparatus was stopped. After cooling the production apparatus, the produced titanium-based hydrogen storage alloy was taken out.

FIG. 4 is a characteristic diagram showing the results of X-ray diffraction of a titanium-based hydrogen storage alloy produced by uniform heating. The horizontal axis of the figure indicates the angle 2θ formed by the incident X-ray and the diffraction line, and the vertical axis indicates the signal intensity of the diffraction line in arbitrary units. The peak shown in the figure is a peak attributed to TiH ₂ , and it was found that high-purity TiH ₂ was produced. It is estimated that the fact that the pressure of the hydrogen gas is reduced during the operation of the production apparatus corresponds to the fact that Ti reacts with the hydrogen gas to produce TiH ₂ . That is, the titanium-based hydrogen storage alloy is combusted and synthesized by uniformly heating the sample S to 600 ° C. or higher in a hydrogen gas atmosphere. As shown in FIG. 3, the decrease in the pressure of the hydrogen gas occurs at a pressure of less than 0.9 MPa, and the titanium-based hydrogen storage alloy is combusted and synthesized from the hydrogen gas and the sample S in a hydrogen gas atmosphere of less than 0.9 MPa. It is clear that this reaction is occurring.

Next, a method for combusting and synthesizing a titanium-based hydrogen storage alloy by igniting the sample S will be described using examples. A sample S made of titanium powder having a particle size of 45 μm or less and a purity of about 99% was placed on the horizontal crucible 11, and a titanium-based hydrogen storage alloy manufacturing apparatus shown in FIG. 1 was set. The sample S is sprayed without being compacted and placed on the horizontal crucible 11. Hydrogen gas was supplied from the gas supply pipe 31 into the pressure vessel 21, and the pressure of the hydrogen gas in the pressure vessel 21 was set to 0.9 MPa. Ignition was performed by supplying current from the current supply unit 42 to the ignition wire 12 in a state where the pressure of the hydrogen gas in the pressure vessel 21 was 0.9 MPa. In addition, you may perform operation which preheats the temperature of the sample S to predetermined temperature using the heater 14 before ignition. By ignition, a part of the titanium powder contained in the sample S is locally heated, and a synthetic reaction occurs in which titanium and hydrogen gas react to synthesize TiH ₂ which is a titanium-based hydrogen storage alloy. Since the synthesis reaction of TiH ₂ is an exothermic reaction, the other part of the sample S is heated by the heat generated by causing the synthesis reaction of a part of the sample S, and further the synthesis reaction of TiH ₂ occurs. In this manner, the TiH ₂ synthesis reaction occurs continuously upon ignition, and finally the TiH ₂ synthesis reaction is performed on the entire sample S.

FIG. 5 is a characteristic diagram showing temperature and pressure histories in an example in which a titanium-based hydrogen storage alloy was combusted and synthesized by ignition. In the figure, the horizontal axis indicates time, and the vertical axis indicates temperature and pressure. FIG. 5 shows a history of the pressure of the hydrogen gas in the pressure vessel 21 and the sample temperature. The sample temperature rapidly rises to a temperature of 900 ° C. or higher by ignition, and at the same time, the pressure of hydrogen gas is reduced. That is, by heating a part of the sample S to 900 ° C. or higher by ignition, a TiH ₂ synthesis reaction occurs, and a TiH ₂ synthesis reaction occurs continuously by reaction heat. After the TiH ₂ synthesis reaction propagates to the entire sample S, the sample temperature gradually decreases, but the hydrogen gas pressure also gradually decreases, and it is clear that the TiH ₂ synthesis reaction is proceeding steadily. It is. The decrease rate of the sample temperature decreases at around 700 ° C. This is due to heat generation due to Ti reacting with hydrogen gas again after decomposition of TiH _{2 in} a high temperature range. After cooling the production apparatus, the produced titanium-based hydrogen storage alloy was taken out. In addition, you may perform operation which replenishes hydrogen gas with the fall of the pressure of hydrogen gas.

As a result of analyzing the produced titanium-based hydrogen storage alloy, high-purity TiH ₂ was produced. The decrease in the pressure of the hydrogen gas is presumed to correspond to the fact that Ti reacts with the hydrogen gas to produce TiH ₂ . As shown in FIG. 5, it can be seen that a reaction in which the titanium-based hydrogen storage alloy is combusted and synthesized from hydrogen gas and the sample S in a hydrogen gas atmosphere of less than 0.9 MPa is generated by ignition. That is, it has been clarified that a highly pure titanium-based hydrogen storage alloy can be produced in a hydrogen gas atmosphere of less than 0.9 MPa even by the ignition method.

  In the present invention, it is effective for efficient production of a titanium-based hydrogen storage alloy to produce a sample S which is a raw material powder by pulverizing a raw material mainly composed of titanium. A sample S was manufactured by pulverizing the raw material in an inert gas atmosphere using an airtight ball mill, and combustion synthesis of a titanium-based hydrogen storage alloy was performed. When the particle size of the sample S was 1 mm and 45 μm, the combustion synthesis of the titanium-based hydrogen storage alloy was completed more quickly when the particle size was 45 μm. That is, by crushing the raw material, the reaction interface of the raw material containing titanium is increased, and the combustion synthesis of the titanium-based hydrogen storage alloy proceeds smoothly, so that the titanium-based hydrogen storage alloy can be efficiently produced. Become. The raw material may be pulverized in hydrogen gas.

In the above-described embodiments, a form in which titanium powder is reacted with hydrogen gas to generate TiH ₂ is shown. However, the present invention is not limited to this, and titanium-based hydrogen storage is performed by reacting titanium with another element. The form which manufactures an alloy may be sufficient. Next, the Example which manufactures TiFe which is a titanium base hydrogen storage alloy using this invention is described.

FIG. 6 is a schematic cross-sectional view showing a method of placing raw material powder on the horizontal crucible 11 in order to produce TiFe. As a raw material powder, 200 g of a sample S in which titanium powder and iron powder are mixed at a molar ratio of 1: 1 is spread and placed on the horizontal crucible 11, and further, the sample S is covered with titanium powder and spread. An ignition wire 12 is disposed in contact with the titanium powder. The other configuration of the titanium-based hydrogen storage alloy manufacturing apparatus is the same as the configuration shown in FIG. Hydrogen gas was supplied from the gas supply pipe 31 into the pressure vessel 21, and the pressure of the hydrogen gas in the pressure vessel 21 was set to 0.5 MPa. Ignition was performed by supplying current from the current supply unit 42 to the ignition wire 12 in a state where the pressure of the hydrogen gas in the pressure vessel 21 was 0.5 MPa. The ignition occurred synthetic reaction in which a titanium powder and the hydrogen gas TiH ₂ is synthesized by the reaction, by using the heat generated by the synthesis reaction of TiH _2, by the reaction with the titanium and iron in the sample S TiFe A synthetic reaction occurs in which is synthesized.

FIG. 7 is a characteristic diagram showing a temperature history in an example in which TiFe is combusted and synthesized by ignition. In the figure, the horizontal axis indicates time, and the vertical axis indicates temperature. FIG. 7 shows a history of the sample temperature. As the synthesis reaction of TiH ₂ occurs continuously by ignition, the sample temperature rapidly rises, and then the synthesis reaction of TiFe proceeds and the sample temperature gradually decreases. After cooling the production apparatus, the produced titanium-based hydrogen storage alloy was taken out. FIG. 8 is a characteristic diagram showing the results of X-ray diffraction of the manufactured TiFe. The horizontal axis of the figure indicates the angle 2θ formed by the incident X-ray and the diffraction line, and the vertical axis indicates the signal intensity of the diffraction line in arbitrary units. The three main peaks shown in the figure are peaks attributed to TiFe, and it is clear that high-purity TiFe is produced.

  In addition, the form which manufactures a titanium base hydrogen storage alloy by making other elements other than Fe react with titanium may be sufficient as the manufacturing method of the titanium base hydrogen storage alloy of this invention. For example, the production method of the titanium-based hydrogen storage alloy of the present invention includes, in addition to titanium and Fe, Cr, Fe, Mg, V, Mn, Zr, Ni, Y, Pr, Nd, Sm, Dy, La, Ce, and Al. A titanium-based hydrogen storage alloy may be manufactured using a raw material powder containing at least one element among, O, C, and Co as the sample S. Various titanium-based hydrogen storage alloys containing these elements can be produced from the raw material powder containing these elements by the same method as that for producing TiFe using the raw material powder containing Fe. . When TiFe is produced using a raw material powder in which O is added to a mixture of titanium powder and iron powder, TiFe oxide is deposited on the surface of TiFe, and hydrogen enters TiFe from the interface between TiFe and the deposited TiFe oxide. Is easier to enter. Therefore, by manufacturing a titanium-based hydrogen storage alloy from a raw material powder containing O in addition to titanium and Fe, it is possible to manufacture a titanium-based hydrogen storage alloy that is easy to store hydrogen. Further, when a titanium-based hydrogen storage alloy is manufactured using raw material powder to which Ni is added, Ni contained in the manufactured titanium-based hydrogen storage alloy acts as a hydrogen separation catalyst. Therefore, by manufacturing a titanium-based hydrogen storage alloy from raw material powder containing titanium as the main component and containing Ni, a titanium-based hydrogen storage alloy that can easily dissociate hydrogen when using the stored hydrogen is manufactured. It becomes possible to do. Thus, according to the present invention, it is possible to produce a titanium-based hydrogen storage alloy having properties according to the application by adjusting the components to be contained.

  As described above in detail, in the present invention, titanium and hydrogen react with each other by the combustion synthesis in which the raw material powder containing titanium as a main component is uniformly heated in a hydrogen gas atmosphere of less than 0.9 MPa. A storage alloy can be produced. Since the pressure at the time of combustion synthesis of the titanium-based hydrogen storage alloy can be made less than 0.9 MPa, it is easier to ensure safety and comply with laws and regulations than before, and mass production of the titanium-based hydrogen storage alloy becomes easier. Since the pressure in the pressure vessel 21 can be reduced to less than 0.9 MPa, the durability of the pressure vessel 21 can be reduced, and a titanium-based hydrogen storage alloy production apparatus can be produced at a lower cost than before. It becomes. Therefore, the cost of the titanium-based hydrogen storage alloy to be manufactured can be reduced. Further, since the pressure in the pressure vessel 21 could be reduced to less than 0.9 MPa, the titanium-based hydrogen storage alloy manufacturing apparatus has an internal heating type in which the heater 14 for heating the raw material powder is provided in the pressure vessel 21. Could be configured. By making the titanium-based hydrogen storage alloy manufacturing equipment internal heating type, rapid temperature control becomes possible, and it is possible to manufacture titanium-based hydrogen storage alloys that require a temperature higher than the conventional limit. Become. Therefore, it is possible to manufacture other types of titanium-based hydrogen storage alloys depending on the application. Also, by supplying hydrogen gas as the hydrogen gas in the hydrogen gas atmosphere decreases, it compensates for the decrease in hydrogen gas due to the formation of titanium-based hydrogen storage alloy, and efficiently manufactures titanium-based hydrogen storage alloy Is possible.

  Further, in the present invention, a part of the raw material powder mainly composed of titanium is locally heated in a hydrogen gas atmosphere of less than 0.9 MPa, whereby titanium and hydrogen react with each other to react with titanium-based hydrogen storage alloy. Reactions in which combustion is synthesized occur continuously, and a titanium-based hydrogen storage alloy can be produced. In addition to being able to manufacture a titanium-based hydrogen storage alloy in a hydrogen gas atmosphere of less than 0.9 MPa, it is possible to manufacture a titanium-based hydrogen storage alloy with a small input energy, thus reducing the energy cost of the titanium-based hydrogen storage alloy. Can be reduced.

  In addition, the raw material powder is sprayed without being compacted and placed on the horizontal crucible 11, and hydrogen gas can easily diffuse in the raw material powder in a hydrogen gas atmosphere. Contact with hydrogen gas is easy, and a reaction in which the titanium-based hydrogen storage alloy is synthesized by combustion is efficiently performed. Moreover, by mechanically grinding the raw material, the reaction interface of the raw material is increased, the reaction for synthesizing the titanium-based hydrogen storage alloy is facilitated, and the titanium-based hydrogen storage alloy can be efficiently produced. Become.

  In the present embodiment, the titanium-based hydrogen storage alloy manufacturing apparatus of the present invention has a form including both the ignition wire (local heating means) 12 and the heater (uniform heating means) 14. Even if it is a form provided with either, it is possible to implement | achieve the manufacturing method of the titanium base hydrogen storage alloy of this invention. Moreover, in this Embodiment, although the form which mounts the sample S which is raw material powder in the horizontal crucible 11 was shown, if raw material powder is the state which is not compacted, raw material powder will be used with a vertical crucible. Even if the body is held, the present invention can be realized. Moreover, in this Embodiment, although the form which used the ignition wire 12 which is a heating wire as a local heating means in this invention was shown, this invention is not restricted to this, This invention is the sample of sample S with a burner or a laser. The form which implement | achieved the local heating means by other methods, such as the method of heating a part, may be sufficient.

According to the present invention, it becomes possible to produce a titanium-based hydrogen storage alloy containing high-purity TiH ₂ , and this titanium-based hydrogen storage alloy can generate high-density hydrogen gas, so that it can be used as a hydrogen generation source. Is promising. In addition, the titanium-based hydrogen storage alloy synthesized by the combustion synthesis method used in the present invention suppresses surface oxidation and does not require activation treatment, so that the hydrogen storage capacity can be fully utilized. It is possible and highly useful. Further, according to the present invention, since a titanium-based hydrogen storage alloy can be manufactured at a lower cost and lower energy cost than before, the titanium-based hydrogen storage alloy manufactured according to the present invention can be used as an efficient energy source. Is possible.

It is typical sectional drawing which shows the structure of the manufacturing apparatus of the titanium base hydrogen storage alloy of this invention. It is a typical perspective view which shows a horizontal crucible, a sample, and an ignition wire. It is a characteristic view which shows the log | history of the temperature and pressure in the Example which carried out the combustion synthesis | combination of the titanium base hydrogen storage alloy by heating a sample uniformly. It is a characteristic view which shows the result of the X-ray diffraction of the titanium base hydrogen storage alloy manufactured by uniform heating. It is a characteristic view which shows the log | history of the temperature and pressure in the Example which carried out the combustion synthesis | combination of the titanium base hydrogen storage alloy by ignition. It is typical sectional drawing which shows the method of mounting raw material powder in a horizontal crucible in order to manufacture TiFe. It is a characteristic view which shows the log | history of the temperature in the Example which carried out the combustion synthesis | combination of TiFe by ignition. It is a characteristic view which shows the result of the X-ray diffraction of manufactured TiFe.

Explanation of symbols

11 Horizontal crucible 12 Ignition wire (local heating means)
13 Thermocouple 14 Heater (uniform heating means)
DESCRIPTION OF SYMBOLS 21 Pressure vessel 22 Heat insulating material 30 Hydrogen gas control part 31 Gas supply pipe 32 Gas discharge pipe 41 Temperature control part 42 Current supply part S Sample (raw material powder)

Claims (8)

Production of a titanium-based hydrogen storage alloy characterized by manufacturing a titanium-based hydrogen storage alloy by substantially uniformly heating a raw material powder mainly composed of titanium in a hydrogen gas atmosphere of less than 0.9 MPa. Method. The method for producing a titanium-based hydrogen storage alloy according to claim 1, wherein hydrogen gas is supplied as the hydrogen gas decreases in the hydrogen gas atmosphere. The raw material powder mainly composed of titanium is enclosed in a hydrogen gas atmosphere of less than 0.9 MPa,
Titanium characterized in that a part of the raw material powder is locally heated to a temperature necessary for a synthesis reaction in which a part of the raw material powder reacts to synthesize a titanium-based hydrogen storage alloy. A method for producing a base hydrogen storage alloy.   The method for producing a titanium-based hydrogen storage alloy according to any one of claims 1 to 3, wherein the raw material powder is dispersed in a substantially horizontal plane. The titanium base according to any one of claims 1 to 4, wherein the raw material powder is produced by mechanically pulverizing a raw material mainly composed of titanium in an inert gas or hydrogen gas. A method for producing a hydrogen storage alloy. In addition to titanium, the raw material powder is at least one of Cr, Fe, Mg, V, Mn, Zr, Ni, Y, Pr, Nd, Sm, Dy, La, Ce, Al, O, C, and Co. An element is contained. The manufacturing method of the titanium base hydrogen storage alloy as described in any one of Claim 1 thru | or 5 characterized by the above-mentioned. A horizontal crucible on which raw material powder mainly composed of titanium is placed;
Uniform heating means for substantially uniformly heating the raw material powder placed in the horizontal crucible;
A pressure vessel that houses the horizontal crucible and the uniform heating means;
And a means for filling the pressure vessel with hydrogen gas and controlling the pressure of the hydrogen gas in the pressure vessel to less than 0.9 MPa. A horizontal crucible on which raw material powder mainly composed of titanium is placed;
Local heating means for locally heating a part of the raw material powder placed in the horizontal crucible;
A pressure vessel enclosing the horizontal crucible and the local heating means in a hydrogen gas atmosphere of less than 0.9 MPa,
The local heating means is configured to heat up to a temperature necessary for causing a synthesis reaction in which a part of the raw material powder reacts in the hydrogen gas atmosphere to synthesize a titanium-based hydrogen storage alloy. An apparatus for producing a titanium-based hydrogen storage alloy, comprising:

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