JP2010260789A - Method for generating hydrogen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for generating hydrogen capable of efficiently generating hydrogen useful for a fuel for a fuel cell without heating to a high temperature under a controllable condition. <P>SOLUTION: The method for generating hydrogen includes bringing borane-ammonia represented by the chemical formula: NH<SB>3</SB>BH<SB>3</SB>into contact with a solid acid (1) or carbon dioxide (2) in the presence of water. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hydrogen generation method.

  Hydrogen gas can be generated by electrolyzing water; reacting metal with acid; reacting metal hydride with water; reforming methyl alcohol or natural gas with steam; hydrogen storage alloy; Various methods are known, such as a method of releasing hydrogen from hydrogen storage materials such as activated carbon, carbon nanotubes, and lithium-nitrogen materials. However, these methods have drawbacks such as requiring a large amount of energy to generate hydrogen, a small amount of hydrogen generation with respect to the raw materials used, and a large-scale facility. For this reason, these methods can be used for production on a factory scale or generation of hydrogen to the extent that they can be used in laboratories. It is unsuitable as a hydrogen supply method for automobile fuel cells; portable fuel cells for mobile phones and personal computers.

On the other hand, metal hydrides such as LiAlH ₄ and NaBH ₄ are used in laboratories as hydrogenation reagents, but when they come into contact with water, a large amount of hydrogen is temporarily generated to cause an explosive phenomenon. It must be handled with care and is also unsuitable as a hydrogen source for the fuel cell described above.

A method for generating hydrogen from an alkaline aqueous solution of tetrahydroborate such as NaBH ₄ has also been reported, but this method requires control of the alkali concentration (pH value). Attention is necessary (see Non-Patent Documents 1 and 2, Patent Documents 1 and 2).

In addition, a method of releasing hydrogen by utilizing thermal decomposition of borane / ammonia represented by the chemical formula: NH ₃ BH ₃ has been reported, but this method is used to cause thermal decomposition by heating to high temperature. In addition, a large amount of energy is required, and control of the reaction is difficult (Non-patent Documents 3 and 4).

Japanese Patent Laid-Open No. 2001-19401 JP 2002-241102 A

S. C. Amendola et al., International Journal of Hydrogen Energy, 25 (2000), 969-975 ; Z. P. Li et al., Journal of Power Source, 126 (2004) 28-33 V. Sit, et al., Thermochimica Acta, 113 (1987) 379 A. T-Raissi, Proceedings of the 2002 US DOE Hydrogen Program Review

The present invention has been made in view of the current state of the prior art described above, and its main purpose is to improve efficiency under controllable conditions without heating hydrogen gas used as fuel or the like of a fuel cell to a high temperature. It is to provide a novel method for generating hydrogen gas that can be generated well.

The present inventor has made various studies on hydrogen gas generation methods, focusing on borane / ammonia NH ₃ BH ₃ as a hydrogen generation source. As a result, borane / ammonia is soluble in water, and its aqueous solution has high stability, but when it is brought into contact with a specific substance, it can generate hydrogen, and the amount of hydrogen generated and generated It has been found that the control of the speed and the like can be easily performed, and the present invention has been completed here.

That is, the present invention provides the following hydrogen generation method and hydrogen supply method to the fuel cell.
1. A method for generating hydrogen, comprising bringing borane / ammonia represented by the chemical formula: NH ₃ BH ₃ into contact with at least one catalyst selected from the group consisting of a metal catalyst and a metal compound catalyst in the presence of water.
2. Item 2. The method for generating hydrogen according to Item 1, wherein the catalyst is at least one selected from the group consisting of platinum, palladium, nickel, cobalt, rhodium, and compounds containing these metals.
3. A method for generating hydrogen, comprising bringing borane / ammonia represented by the chemical formula: NH ₃ BH ₃ into contact with a solid acid in the presence of water.
4). Item 4. The method for generating hydrogen according to Item 3, wherein the solid acid is at least one selected from the group consisting of a polymer compound having a sulfonic acid group and an H-substituted zeolite type compound.
5). A method of generating hydrogen, comprising contacting borane / ammonia represented by the chemical formula: NH ₃ BH ₃ with carbon dioxide in the presence of water.
6). A method for supplying hydrogen to a fuel cell, wherein the hydrogen generated by the method according to any one of items 1 to 5 above is used as a hydrogen source for the fuel cell.

In the hydrogen generation method of the present invention, borane / ammonia represented by the chemical formula: NH ₃ BH ₃ is used as a hydrogen generation component. Borane / ammonia is a known compound and is a colorless compound having a density of 2.27 g / cm ³ . Although borane / ammonia is soluble in water, it hardly reacts with water at a temperature around room temperature, exists as a relatively stable aqueous solution, and its handling is easy and safe.

  There is no limitation in particular about the kind of borane / ammonia, and what is generally marketed can be used as it is. Further, other components may be included at the same time as long as there is no adverse effect on the hydrogen generation.

  The method for generating hydrogen of the present invention uses the above-described borane / ammonia as a hydrogen generating component, and in the presence of water, (1) at least one catalyst selected from the group consisting of a metal catalyst and a metal compound catalyst, 2) A method of contacting with a solid acid or (3) carbon dioxide. Hereinafter, each of these methods is demonstrated concretely.

Method of contacting with metal catalyst or metal compound catalyst FIG. 1 shows the results when a 0.3% by weight aqueous solution of borane / ammonia is left in an argon atmosphere at room temperature, immediately after being left, after 6 days, and after 30 days. It illustrates a ¹¹ B NMR spectrum. As is clear from this spectrum, in ¹¹ B NMR measurement, NH ₃ BH
_The peak attributed to ₃ (δ = -24 ppm) hardly changed, and no new peak was observed even after 1 month. This result shows that NH ₃ BH ₃ hardly reacts with water even after one month at room temperature.

On the other hand, according to the study of the present inventor, borane / ammonia reacts rapidly with water according to the following chemical reaction formula (1) by contacting with a metal catalyst or a metal compound catalyst in the presence of water. It was revealed that hydrogen was generated.

In this reaction, the amount of hydrogen generated is the sum of hydrogen generated by decomposition of NH ₃ BH ₃ itself and hydrogen from water, so the total amount of NH ₃ BH ₃ and H ₂ O involved in the reaction is As a result, 8.9 wt% of hydrogen is generated, and the hydrogen generation efficiency becomes very high.

  As the metal catalyst, metals belonging to Group 9 of the periodic table, metals belonging to Group 10, and the like are preferable, and cobalt, nickel, rhodium, palladium, platinum, and the like are particularly preferable.

  As the metal compound catalyst, a compound containing a metal belonging to Group 9 and a compound containing a metal belonging to Group 10 can be used. Since the hydrogen generation reaction in the present invention proceeds in a strong reducing atmosphere, it is considered that any compound containing the above metal is reduced to a metal during the reaction and effectively acts as a catalyst. Specific types of compounds are not particularly limited, and various compounds such as salts such as sulfates, oxides, and complex compounds can be used.

Specific examples of metals and metal compounds exhibiting high catalytic activity include platinum oxide, platinum, potassium tetrachloroplatinate (II), palladium sulfate, palladium, nickel sulfate, cobalt sulfate, di-μ-chlorobis (η-cycloocta- 1,5-diene) rhodium (I) ([Rh (1,5-COD) (μ-Cl)] ₂ )
Etc.

  In this invention, a metal catalyst and a metal compound catalyst can be used individually by 1 type or in mixture of 2 or more types.

In the method of the present invention, borane / ammonia represented by the chemical formula: NH ₃ BH ₃ may be brought into contact with at least one catalyst selected from the group consisting of a metal catalyst and a metal compound catalyst in the presence of water. The specific treatment method is not particularly limited, for example, a method of adding water to a mixture of borane / ammonia and a catalyst; either or both of borane / ammonia and a catalyst are previously prepared as an aqueous solution or an aqueous dispersion, It is possible to adopt a method of mixing these. In these methods, for example, in the former case, the hydrogen generation rate, generation amount, and the like can be easily controlled by adjusting the water addition rate, addition amount, and the like. In the latter case, by adjusting the mixing rate, mixing ratio, concentration of the aqueous solution, and the like of borane / ammonia and the catalyst, the hydrogen generation rate, generation amount, etc. can be easily controlled.

  As shown in the above reaction formula, 2 mol of water reacts with 1 mol of borane / ammonia to generate hydrogen, so in order to sufficiently react the borane / ammonia used as a raw material, the amount of water used is It is preferable that the amount be about 2 mol or more per 1 mol of borane / ammonia.

  The solubility of borane / ammonia in water is about 26% by weight at 23 ° C., and when an aqueous solution is prepared in advance, an aqueous solution up to a saturated concentration can be used. An aqueous solution containing ammonia as an insoluble component may be used. The lower limit of the borane / ammonia concentration in the borane / ammonia aqueous solution is also not particularly limited. For example, an aqueous solution having a very low concentration of borane / ammonia concentration of 0.1% by weight or less can be used.

  About the usage-amount of a catalyst, since hydrogen generation | occurrence | production reaction can be accelerated | stimulated when the amount increases, what is necessary is just to determine suitably in consideration of the required hydrogen generation speed, cost, etc. For example, the amount of catalyst can be selected from a wide range of about 0.0001 to 10 mol per mol of borane / ammonia, but considering the balance of reaction rate, catalyst cost, etc., for example, The amount of catalyst may be about 0.001 to 0.5 mol with respect to 1 mol of ammonia.

  The reaction temperature is not particularly limited, but is 0 ° C. or more, which is the freezing point of water, preferably about 80 ° C. or less, and more preferably about 10 to 50 ° C.

  There is no limitation in particular about the pressure and atmosphere in the reaction system at the time of reaction, and it can select suitably.

Method of contacting with solid acid Also when contacting with a solid acid, according to the chemical reaction formula (1), borane / ammonia and water react rapidly to generate hydrogen.

Any solid acid can be used without particular limitation as long as it does not dissolve in the reaction solution and exhibits properties as a Bronsted acid or Lewis acid. For example, a polymer compound having a sulfonic acid group, an H-substituted zeolite type compound, or the like can be used. The concentration of the acid sites of these solid acids is not particularly limited. For example, a solid acid having a cation exchange capacity of about 0.01 to 10 mg equivalent / g, preferably about 0.1 to 5 mg equivalent / g. Can be used.

As the polymer compound having a sulfonic acid group, the structure of the polymer portion is not limited. If the sulfonic acid group is bonded, the polymer compound is effective as a catalyst but does not change in the reaction system. It is preferable. In general, a styrene resin such as a styrene polymer, a copolymer of styrene and divinylbenzene, or a sulfonic acid group bonded to a side chain such as a fluorine resin is easily industrially available as an ion exchange resin. . For example, as styrene resin, Amberlyst (registered trademark of Rohm and Haas), Amberlite (registered trademark of Rohm and Haas), Dowex (DOWEX) (registered trademark of Dow Chemical Company) ) Etc., and those commercially available. Examples of the fluorine-based resin include the following structural formula

Nafion NR-50, Nafion SAC-13 (both Du P
For example, perfluorosulfonic acid commercially available under a trade name such as a registered trademark of Ont Corporation may be used.

  As the H-substituted zeolite type compound, for example, H-substituted Y-type zeolite, H-substituted β-type zeolite, H-substituted mordenite type zeolite and the like can be used.

For the method of bringing borane / ammonia represented by the chemical formula: NH ₃ BH ₃ into contact with a solid acid in the presence of water, at least one catalyst selected from the group consisting of the above metal catalysts and metal compound catalysts is used. A method similar to that used can be employed.

  The amount of water used, reaction conditions, and the like may be the same as in the case of using the above-described catalyst.

  The amount of solid acid used depends on the strength, concentration, etc. of the acid point of the solid acid to be used, but cannot be determined unconditionally. For example, the acid in the solid acid with respect to 1 mol of borane / ammonia. The number of equivalent points can be about 0.0001 to 10 equivalents, preferably about 0.01 to 2 equivalents.

  In addition, the product may interact with the acid sites of the solid acid, and the activity of the acid sites may decrease. In this case, the activity of the solid acid is increased by washing with an acidic solution after the reaction. Can be played.

Method of contacting with carbon dioxide In the present invention, hydrogen can also be generated by a method of contacting borane / ammonia with carbon dioxide in the presence of water.

  As a specific method, for example, a method of introducing carbon dioxide from a gas phase portion or a liquid phase portion into a reaction vessel containing a borane / ammonia aqueous solution can be mentioned. The amount of carbon dioxide introduced is not particularly limited, but for example, carbon dioxide may be introduced at a pressure of about 0.01 MPa to 0.5 MPa, preferably about 0.03 MPa to 0.2 MPa. Carbon dioxide may be used alone or in combination with an inert gas.

  About the usage-amount of water, reaction conditions, etc., what is necessary is just the same as the case where the above-mentioned catalyst is used.

  In this method, the amount of hydrogen generated, the rate of generation, etc. can be easily controlled by adjusting the amount of carbon dioxide introduced, the rate of introduction, the concentration of borane / ammonia solution, and the like.

Method of using the hydrogen generation method The hydrogen generated by the method of the present invention can be directly supplied to the fuel cell as fuel for the fuel cell, for example. In particular, since hydrogen can be generated at temperatures near room temperature, and the hydrogen generation rate, generation amount, etc. can be controlled, fuel cells for automobiles; portable fuel cells for mobile phones, personal computers, etc. This method is highly useful as a hydrogen supply method.

  The generated hydrogen can be collected and stored in a container filled with a hydrogen storage alloy, for example. It is also possible to control the internal pressure of the generated hydrogen by using a hydrogen storage alloy and adjusting the temperature according to the equilibrium pressure-temperature relationship.

  According to the hydrogen generation method of the present invention, hydrogen gas can be efficiently generated under controllable conditions without heating to a high temperature. The hydrogen gas generated by the method of the present invention is highly useful as a fuel for, for example, a fuel cell for automobiles and a portable fuel cell.

The figure which shows the time-dependent change of ¹¹ B NMR spectrum when 0.3 weight% aqueous solution of borane ammonia is left at room temperature in argon atmosphere. The graph which shows the relationship between the hydrogen release amount and reaction time which were measured in Examples 1, 2, and 4-9. The graph which shows the relationship between the hydrogen release amount measured in Examples 10-12, and reaction time. The graph which shows the relationship between the hydrogen release amount and reaction time which were measured in Examples 14-16. FIG. 18 shows the time course of ¹¹ B NMR spectrum measured in Example 17. FIG.

  Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1
A 4.0 ml platinum oxide (PtO ₂ ) powder was placed in a 30 ml two-necked flask, a gas burette was connected to one of its mouths, and a 50 ml isobaric separatory funnel was connected to the other. . In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

The system was evacuated using a vacuum pump, purged with argon gas, a borane / ammonia aqueous solution was poured into the two-necked flask from the isobaric separatory funnel, and stirring was continued at room temperature. A gas release of 39 ml was observed 1 minute after the start of stirring, 65 ml after 2 minutes, 87 ml after 5 minutes, 105 ml after 10 minutes, and 107 ml after 30 minutes.

As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 3 times the mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 2
Into a 30 ml two-necked flask, 4.0 mg of platinum (Pt) powder was placed, a gas burette was connected to one of the mouths, and a 50 ml isobaric separatory funnel was connected to the other. In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

  The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature.

Outgassing of 12.5 ml 1 minute after the start of stirring, 23.5 ml after 2 minutes, 53.5 ml after 5 minutes, 97.5 ml after 10 minutes, and 105 ml after 30 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 3 times the mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 3
After completion of the reaction in Example 2, the platinum (Pt) powder was recovered by filtration, put into a 30 ml two-necked flask, a gas burette was connected to one of its mouths, and 50 ml of the other mouth. An isobaric separatory funnel was connected. 50 mg borane / ammonia (NH ₃ BH ₃ , purity 90%) for isobaric separator
15 ml of an aqueous solution in which was dissolved was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature.

Gas release of 11 ml was observed 1 minute after the start of stirring, 22 ml after 2 minutes, 51 ml after 5 minutes, 97 ml after 10 minutes, and 105 ml after 30 minutes. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 3 times the mol of borane / ammonia used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 4
Place a 4.8 mg potassium tetrachloroplatinate (II) powder (K ₂ PtCl ₄ ) in a 30 ml two-necked flask, connect a gas burette to one of its mouths, and add 50 ml to the other. An isobaric separatory funnel was connected. In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

  The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature.

Outgassing of 1.5 ml after 1 minute of stirring, 5.5 ml after 2 minutes, 18.5 ml after 5 minutes, 45.5 ml after 10 minutes, and 99 ml after 30 minutes was observed. Gas chromatography (GC) and mass spectrometry (MS)
As a result, it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.8 times mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 5
A 5.0 ml palladium sulfate (PdSO ₄ ) powder was placed in a 30 ml capacity two-necked flask, a gas burette was connected to one of its mouths, and a 50 ml isobaric separatory funnel was connected to the other. . In an isobaric separatory funnel, 15 mg of 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved.
1 aqueous solution was added.

  The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature.

Outgassing of 5.5 ml after 5 minutes from the start of stirring, 8.0 ml after 10 minutes, 27 ml after 60 minutes, 47 ml after 120 minutes, and 71 ml after 240 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was twice as much as that of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 6
4.5 mg of palladium (Pd) powder was placed in a 30 ml two-necked flask, a gas burette was connected to one of the ports, and a 50 ml isobaric separatory funnel was connected to the other. In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

  The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature.

Outgassing of 3.0 ml after 5 minutes from the start of stirring, 35 ml after 10 minutes, 15.5 ml after 60 minutes, 27.5 ml after 120 minutes, 53 ml after 240 minutes, and 71.5 ml after 360 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was twice as much as that of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 7
A 4.3 ml nickel sulfate (NiSO ₄ ) powder was placed in a 30 ml two-necked flask, a gas burette was connected to one of its mouths, and a 50 ml isobaric separatory funnel was connected to the other. . In an isobaric separatory funnel, 15 mg of 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved.
1 aqueous solution was added.

  The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature.

Outgassing of 1.0 ml 5 minutes after the start of stirring, 1.5 ml after 10 minutes, 8.0 ml after 60 minutes, 31 ml after 120 minutes, 86.5 ml after 240 minutes, and 92 ml after 300 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.6 times moles of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 8
A 4.3 ml cobalt sulfate (CoSO ₄ ) powder was placed in a 30 ml two-necked flask, a gas burette was connected to one of its mouths, and a 50 ml isobaric separatory funnel was connected to the other. . In an isobaric separatory funnel, 15 mg of 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved.
1 aqueous solution was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature. Outgassing of 1.0 ml 5 minutes after the start of stirring, 3.0 ml after 10 minutes, 43 ml after 30 minutes, 95 ml after 60 minutes, and 98 ml after 80 minutes was observed. Gas chromatography (GC) and mass spectrometry (MS)
As a result, it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.8 times mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 9
5.0 mg of di-μ-chlorobis (η-cycloocta-1,5-diene) rhodium (I) ([Rh (1,5-COD) (μ-Cl)] ₂ ) in a 30-ml two-necked flask The powder was put, a gas burette was connected to one of the ports, and a 50 ml isobaric separatory funnel was connected to the other port. For the isobaric separator,
15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

  The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature.

Outgassing of 2.0 ml after 1 minute of stirring, 6.0 ml after 2 minutes, 28 ml after 5 minutes, 75 ml after 10 minutes, 91 ml after 30 minutes, and 91 ml after 60 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.6 times moles of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.
In addition, it was confirmed that the fuel cell was operated by introducing the gas into the solid polymer fuel cell as it was.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

The graph of FIG. 2 shows the relationship between the amount of hydrogen released and the reaction time measured in Examples 1, 2, and 4-9. From this result, it can be seen that each catalyst used in the above examples is effective for the hydrogen generation reaction by the reaction of borane / ammonia (NH ₃ BH ₃ ) and water.

Example 10
1700 mg of H-type perfluorosulfonic acid resin (trade name: Nafion NR-50, DuPont) (cation exchange capacity of about 0.8 mg equivalent / g resin) and 15 ml of water in a 50 ml two-necked flask The gas burette was connected to one of the ports, and a 50 ml isobaric separatory funnel was connected to the other port. In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature. Outgassing of 2.0 ml after 1 minute of stirring, 6.5 ml after 5 minutes, 15.0 ml after 10 minutes, 47.5 ml after 30 minutes, 75.5 ml after 60 minutes, and 92 ml after 120 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.6 times moles of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 11
600 ml of H-type styrene ion exchange resin (trade name: DOWEX 50WX8-100, Dow Chemical Company) (cation exchange capacity of about 1.7 mg equivalent / ml resin)) and 15 ml Water was added, a gas burette was connected to one of the ports, and a 50 ml isobaric separatory funnel was connected to the other port. In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature. A gas release of 49.5 ml 1 minute after the start of stirring, 79.5 ml after 2 minutes, 88.5 ml after 3 minutes, 94.5 ml after 5 minutes, and 97.5 ml after 10 minutes was observed. As a result of gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.7 times mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 12
600 ml of H-type styrene ion exchange resin (trade name: Amberlyst 15, Rohm and Haaas) ((cation exchange capacity of about 4.7 mg equivalent / g resin)) and 15 ml in a 50 ml capacity two-necked flask
Of water, a gas burette was connected to one of the ports, and a 50 ml isobaric separatory funnel was connected to the other port. The isobaric separatory funnel contains 50 mg of borane / ammonia (NH ₃ BH ₃ ,
15 ml of an aqueous solution in which 90% purity was dissolved was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature. A gas release of 40 ml was observed 1 minute after the start of stirring, 76.5 ml after 2 minutes, 91.5 ml after 3 minutes, 99.5 ml after 5 minutes, and 101 ml after 10 minutes. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.8 times mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

The relationship between the hydrogen release amount measured in Examples 10 to 12 and the reaction time is shown in the graph of FIG. From this result, it can be seen that each solid acid used in Examples 10 to 12 is effective for a hydrogen generation reaction by a reaction between borane / ammonia (NH ₃ BH ₃ ) and water.

Example 13
After completion of the reaction in Example 12, the ion exchange resin (Amberlyst 15) was recovered by filtration, immersed in 10 ml of 10% sulfuric acid for 1 hour, filtered, washed 5 times with water, and 30 minutes at 90 ° C. Dried.

Place the ion exchange resin (Amberlyst 15) collected in the above method and 15 ml of water into a 50 ml two-necked flask, connect a gas burette to one of its mouths, and add 50 ml of etc. to the other mouth. A pressure separatory funnel was connected. In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature. Outgassing of 39 ml was observed 1 minute after the start of stirring, 75 ml after 2 minutes, 90.5 ml after 3 minutes, 99 ml after 5 minutes, and 100 ml after 10 minutes. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.8 times mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  In addition, it was confirmed that the hydrogen gas generated by the above-described method was introduced into the solid polymer fuel cell as it was to operate the fuel cell.

Example 14
Put 8 mg of H-substituted Y-type zeolite (SiO ₂ / Al ₂ O ₃ = 4.8) and 15 ml of water into a 50 ml two-necked flask, connect a gas burette to one of its mouths, A 50 ml isobaric separatory funnel was connected to the mouth. In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature. Outgassing of 11 ml 5 minutes after the start of stirring, 21 ml after 10 minutes, 45.5 ml after 30 minutes, 63.5 ml after 60 minutes, and 84 ml after 180 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.4 moles compared to borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 15
Place 7 mg of H-substituted β-type zeolite (SiO ₂ / Al ₂ O ₃ = 25) and 15 ml of water into a 50-ml two-necked flask, connect a gas burette to one of its mouths, and connect the other. A 50 ml isobaric separatory funnel was connected to the mouth. In an isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was previously dissolved was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature. Outgassing of 34 ml after 5 minutes from the start of stirring, 48 ml after 10 minutes, 64 ml after 20 minutes, 73 ml after 30 minutes and 79 ml after 60 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.2 times the mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Example 16
Place 5 mg of H-substituted mordenite zeolite (SiO ₂ / Al ₂ O ₃ = 15) and 15 ml of water in a 50 ml two-necked flask, connect a gas burette to one of its mouths, 50 ml in mouth
An equal pressure separating funnel was connected. In the isobaric separatory funnel, 15 ml of an aqueous solution in which 50 mg of borane / ammonia (NH ₃ BH ₃ , purity 90%) was dissolved was added.

The system was evacuated using a vacuum pump and purged with argon gas. Then, an aqueous borane / ammonia solution was poured into the two-necked flask from an isobaric separatory funnel and stirring was continued at room temperature. Outgassing of 24 ml 5 minutes after the start of stirring, 35 ml after 10 minutes, 61 ml after 30 minutes, 77.5 ml after 60 minutes, and 88 ml after 120 minutes was observed. As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that the released gas was hydrogen. The amount of hydrogen released was 2.5 moles compared to borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

The relationship between the hydrogen release amount and the reaction time measured in the above Examples 14 to 16 is shown in the graph of FIG. From this result, it can be seen that each solid acid used in Examples 14 to 16 is effective for hydrogen generation reaction by reaction of borane / ammonia (NH ₃ BH ₃ ) with water.

Example 17
Put 200 mg borane ammonia (NH ₃ BH ₃ , purity 90%) and 15 ml water (H ₂ O) in a 200 ml two-necked flask connected to a 400 ml gas bag and dissolve by stirring. Then, carbon dioxide at one atmospheric pressure (0.1 MPa) was introduced. The mixture was stirred at room temperature and ¹¹ B NMR was measured over time. FIG. 5 is a graph showing the time course of the ¹¹ B NMR spectrum. From this spectrum, a reaction of 70% borane / ammonia was confirmed after 3 days. Further, in the ¹¹ B NMR spectrum after 7 days, the peak of −24 ppm attributed to borane / ammonia disappeared completely, and only the peak mainly attributed to H ₃ BO ₃ was observed at 19.24 ppm.

As a result of performing gas chromatography (GC) and mass spectrometry (MS), it was confirmed that hydrogen gas was released. The amount of hydrogen released was 2.3 times mol of borane / ammonia (NH ₃ BH ₃ ) used as a raw material.

  Further, it was confirmed that the hydrogen gas generated by the above-described method was directly introduced into the polymer electrolyte fuel cell and the fuel cell was operated.

Claims (4)

A method for generating hydrogen, comprising bringing borane / ammonia represented by the chemical formula: NH ₃ BH ₃ into contact with a solid acid in the presence of water. The method for generating hydrogen according to claim 1, wherein the solid acid is at least one selected from the group consisting of a polymer compound having a sulfonic acid group and an H-substituted zeolite type compound. A method of generating hydrogen, comprising contacting borane / ammonia represented by the chemical formula: NH ₃ BH ₃ with carbon dioxide in the presence of water. A method for supplying hydrogen to a fuel cell, wherein the hydrogen generated by the method according to claim 1 is used as a hydrogen source of the fuel cell.

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