JP2016124730A - High-pressure hydrogen production process and production system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process and system for providing a high-pressure hydrogen that is produced by separating a high-pressure gas comprising carbon dioxide and hydrogen from formic acid dehydrogenation reactor, under a mild condition of not higher than 100°C, without going through a significant pressure increase or pressure decrease process, into hydrogen and carbon dioxide as being at the high-pressure state, and purifying the same.SOLUTION: Provided is a process for producing, in a state as remaining at high-pressure, a higher purity hydrogen-containing gas by allowing a high-pressure gas of carbon dioxide and hydrogen at 7.3 MPa or more from formic acid dehydrogenation reactor, not higher than 32°C, to separate into two phases of a liquid phase in which only carbon dioxide is liquified, and a gas phase in which hydrogen is enriched.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for producing high-pressure hydrogen from a hydrogen storage agent such as formic acid. More specifically, the present invention does not require a compressor for compressing hydrogen and a compression step using this compressor, and formic acid. Provides a series of technologies to obtain high-purity high-pressure hydrogen by phase-separating carbon dioxide and hydrogen in the high-pressure state using the high-pressure state obtained by the mixed gas containing carbon dioxide and hydrogen generated by the decomposition of To do.

  When building a society using hydrogen as energy, when hydrogen is transported or supplied to a fuel cell, it is required to produce highly purified and high-density hydrogen that is more compressed and concentrated. For example, an automobile equipped with a fuel cell must be filled with hydrogen at a pressure of 35 MPa in a 171 L tank in order to secure a cruising range of 600 km.

  In order to supply this high-pressure hydrogen, it is necessary to first produce a mixed gas containing hydrogen, separate and purify the hydrogen therefrom, and compress it. There are a number of techniques for producing a mixed gas containing hydrogen. For example, each raw material is decomposed such as water decomposition method, hydrocarbon compound (methylcyclohexane) decomposition method, ammonia decomposition method, formic acid decomposition method, biomass decomposition method, natural gas decomposition method, etc. Among them, hydrogen is obtained by dehydrogenation reaction.

  However, the mixed gas containing hydrogen obtained by the conventional method requires a purification step to be used as energy for a fuel cell or the like, and requires various gas purification techniques. In addition, since the obtained gas is not at high pressure, in order to supply high-pressure hydrogen, it is necessary to construct a system that combines a compression process and a purification process. This is a major factor in raising costs.

  For example, it is separated and purified by the PSA method (Pressure Swing Absorption, Patent Document 1) or TSA method (Temperature Swing Absorption, Patent Document 2) using a separation membrane or adsorbent, and combined with high pressure and compression by a compressor. Manufactures high pressure hydrogen.

  When a hydrocarbon compound (methylcyclohexane) is used as a hydrogen source, hydrogen is obtained by dehydrogenation reaction, and simultaneously produced toluene (boiling point 121 ° C.) is gas-liquid separated. High-pressure hydrogen that can be supplied to a fuel cell vehicle or the like through an adsorbent is manufactured (Patent Documents 3 and 4). The problems with these technologies are that the dehydrogenation reaction temperature is as high as around 300 ° C, and the generated hydrogen is 0.18 MPa, so hydrogen is compressed to 35 MPa, which is necessary to fill the fuel cell. The compressor for that must be used. The hydrogen compressor has a complicated sealing mechanism for hydrogen that is leaky, has large vibrations and noise, and requires a large amount of energy for compression. To overcome this drawback, the raw material hydrocarbon compound is pressurized from the beginning. A technique has been invented for producing high-pressure hydrogen by increasing the pressure at a high pressure and performing dehydrogenation in that state. However, this technique also requires the energy to pressurize the hydrogen source first (Patent Document 5).

  When ammonia is used as a hydrogen source, hydrogen and nitrogen are generated by a dehydrocracking reaction as in the case of hydrocarbon compounds. The obtained mixed gas separates hydrogen with a separation membrane such as a palladium membrane and supplies it to a fuel cell or the like. However, ammonia is a gas at room temperature and normal pressure, and there is a problem in removing unreacted residual ammonia (Patent Document 6), the driving temperature of the palladium film is 300 ° C. or more (Patent Document 7), and ammonia Since the dehydrogenolysis temperature is 550 ° C. or higher (Patent Document 8), it requires a large amount of energy, including raising the temperature of liquid ammonia, and it is difficult to ensure a balance between the heating energy and the energy obtained. Have the disadvantages.

  On the other hand, when formic acid is used as a hydrogen source, hydrogen, carbon dioxide, and carbon monoxide are generated. However, carbon monoxide promotes deterioration of the electrode, and thus has a drawback that it is difficult to use. In response to this problem, a dehydrogenation technique using a metal complex catalyst that does not generate carbon monoxide has been developed (Patent Documents 9 and 10, Non-Patent Documents 1 to 8). However, it has a drawback that an organic solvent and an amine are required, and a catalyst that operates in water has been developed, but low catalytic activity and durability have been problems (Patent Documents 11 to 15, Non-Patent Document 9). ~ 12). In response to these problems, catalysts that exhibit extremely high activity in the dehydrogenation reaction of formic acid in water have been developed (Patent Documents 16 to 22, Non-Patent Documents 13 to 24).

  However, the gas not containing carbon monoxide obtained with these catalysts is a mixed gas of 1: 1 hydrogen and carbon dioxide, and the maximum generated gas mixture is 2 MPa. On the other hand, in order to obtain high-pressure hydrogen for use in fuel cell vehicles, etc., it is necessary to separate and purify the obtained hydrogen, and it is necessary to further boost the purified hydrogen to 35 MPa or more with a compressor. It is not realistic to install it as it is.

  In order to solve this problem, a technique for separating and purifying carbon dioxide and hydrogen includes a method using hydrogen or a carbon dioxide separation permeable membrane (Patent Documents 23 and 24), a PSA method using a hydrogen adsorption alloy (Patent Document 25), There is a PSA method (Patent Document 26) that removes carbon dioxide with an absorbing solution. However, since it is a technique for obtaining purified hydrogen under low pressure, a pressure increasing step is indispensable in any case.

JP 2014-189480 A Special table 2010-500272 gazette JP 2014-073923 A JP 2005-216774 A JP 2005-200363 A JP 2012-109064 A JP 2011-245459 A JP 2012-162457 A WO2008 / 047312 WO2012 / 070620 Japanese Patent No. 4572393 Japanese Patent No. 4875576 WO2011 / 108730 JP 2010-083730 A JP 2010-208927 A Japanese Patent No. 3968431 Japanese Patent No. 4009728 Japanese Patent No. 4822253 Japanese Patent No. 5030175 PCT / US2012 / 054823 PCT / JP2013 / 051606 Japanese Patent Application No. 2012-062042 JP 2014-1109 A JP 2014-203624 A JP 2012-1380 A JP 2010-143778 A

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The present invention has been made in view of the above-described prior art, and does not use a compressor or compression process for compressing hydrogen to a high pressure, and does not necessarily use the PSA method or the TSA method. It is an object to provide a method and an apparatus for producing high-pressure high-pressure hydrogen.
In addition, the present invention additionally provides a method and apparatus for producing high-purity high-pressure hydrogen without using a compressor or compression process for compressing a hydrogen storage agent that generates hydrogen to a high pressure. Let it be an issue.
Further, the present invention additionally provides a method and an apparatus for separating and producing high-purity high-pressure hydrogen from a high-pressure mixed gas without requiring a cryogenic temperature close to −200 ° C. as in cryogenic separation. To be an important issue.

As a result of intensive studies to achieve the above problems, the present inventors have obtained the following findings (A) to (C).
(A) By decomposing formic acid using a dehydrogenation catalyst, a high-pressure mixed gas of 7.3 MPa or higher, which is higher than the critical pressure of carbon dioxide, is obtained. By using this high-pressure mixed gas, hydrogen is compressed to a high pressure. Without using a compressor or a compression process for this purpose, and without using a purification method such as PSA or TSA, carbon dioxide can be separated from a high-pressure gas mixture at a temperature of 32 ° C. or lower (solid-liquid). High-pressure gas with increased hydrogen purity can be produced.
(B) The formic acid can be supplied to the dehydrogenation reaction vessel without necessarily using a compressor or a compression step for compressing formic acid to a high pressure.
(C) By adjusting the dehydrogenation reaction temperature and the resulting gas pressure to an appropriate range, the temperature from low temperature to near normal temperature (-38) is required without requiring an extremely low temperature near -200 ° C as in cryogenic separation. High-pressure gas with increased hydrogen purity can be produced by gas-liquid separation at a temperature of from 32 ° C. to 32 ° C.

〔前式(１)において、Mは、Ir、Rh、Ru、Co、Os、Ni、Fe、Pd、Pt、またはAuであり、A〜F(A〜Fのうちの１つ〜３つは存在しなくても良い。)は、それぞれ独立に、ハロゲン、リン、窒素、炭素、酸素、硫黄、もしくは水素を配位原子として含む配位子であるか、または、A〜Fのうちの２つは、Mに配位する２座配位子であるか、もしくは、該Mとは別のMを含む4座配位子構造のものであり、mは、正の整数、0、または負の整数である。〕
［５］水素貯蔵剤の脱水素化反応において、下記式(２)または式(３)で表されるものから選択される触媒を用いることを特徴とする[３]または[４]に記載の高圧ガス製造方法。

〔前式(２)において、Mは、Ir、Rh、Ru、Co、Os、Ni、Fe、Pd、Pt、またはAuであり、A〜Bは、それぞれ独立に、窒素、炭素、酸素、もしくは硫黄を配位原子として含む配位子であるか、または、AとBは、Mに配位する２座配位子であり、Lは、芳香族性アニオン配位子、または芳香族性配位子であり、置換基を有している場合は、前記配位子は１つでも複数でも良く、Zは、任意の配位子であるか、または存在せず、mは、正の整数、0、または負の整数である。〕

〔前式(３)において、M¹〜M²は、それぞれ独立に、Ir、Rh、Ru、Co、Os、Ni、Fe、Pd、Pt、またはAuであり、A¹〜A⁴は、それぞれ独立に、窒素、炭素、酸素、もしくは硫黄を配位原子として含む配位子であるか、または、A¹〜A⁴は、M¹とM²に配位する４座配位子であり、L¹〜L²は、それぞれ独立に、芳香族性アニオン配位子、または芳香族性配位子であり、置換基を有している場合は、前記配位子は１つでも複数でも良く、Z¹〜Z²は、それぞれ独立に、任意の配位子であるか、または存在せず、mは、正の整数、0、または負の整数である。〕
［６］ギ酸または／およびギ酸塩の脱水素化反応に下記式(４)〜(１０)で表されるものから選択される触媒を用いることを特徴とする[４]または[５]に記載の高圧ガス製造方法。

〔前記式(４)〜(１０)において、
式中の５員環および６員環は、芳香族性を有するものであり、また、A¹〜A⁴は、いずれも窒素であるか、またはそれぞれ独立に、窒素もしくは炭素であり、X¹〜X¹⁰は、それぞれ独立に、窒素または炭素であり、R¹〜R¹⁰は、それぞれ独立に、水素原子、アルキル基、フェニル基、ニトロ基、ハロゲン基、スルホン酸基(スルホ基)、アミノ基、カルボン酸基(カルボキシル基)、ヒドロキシ基(-OH)、オキシアニオン基(-O^-)、またはアルコキシ基(-OR)(ただし、Xⁱが窒素である場合、その窒素の位置のRⁱは存在しない。)であり、L¹〜L²は、それぞれ独立に、芳香族性アニオン配位子、または芳香族性配位子であり、置換基を有している場合は、前記配位子は１つでも複数でも良く、Z¹〜Z²は、それぞれ独立に、任意の配位子であるか、または存在せず、mは、正の整数、0、または負の整数であり、M¹〜M²は、それぞれ独立に、Ir、Rh、Ru、Co、Os、Ni、Fe、Pd、Pt、またはAuである。〕
［７］水素貯蔵剤の脱水素化反応を高圧反応容器で行い、高圧混合ガスの相分離を気液分離器で行う[１]〜[６]のいずれか１項に記載の高圧水素ガス製造方法。
［８］水素貯蔵剤の脱水素化反応を32〜300℃の反応温度下で行い、高圧混合ガスの相分離を前記反応温度より低い-38〜32℃の相分離温度で行うことを特徴とする[１]〜[７]のいずれか１項に記載の高圧水素ガス製造方法。
［９］相分離温度を０〜32℃、脱水素化反応温度を相分離温度より20〜100℃高い温度とする［８］に記載の高圧水素ガス製造方法。
［１０］高圧反応容器への水素貯蔵剤の供給を連続的または間欠的に行うことを特徴とする[１]〜[９]のいずれか１項に記載の高圧水素ガス製造方法。
［１１］内部が常圧の高圧反応容器へ所定量の水素貯蔵剤を供給後、該水素貯蔵剤を加熱して前記高圧混合ガスを生成し、高圧水素ガスの製造停止まで水素貯蔵剤を追加供給することなく水素濃度の高い高圧ガスを製造することを特徴とする[１]〜[１０]のいずれか１項に記載の高圧水素ガス製造方法。
［１２］水素貯蔵剤の脱水素化反応により全圧が7.3MPa以上の水素と二酸化炭素とを含む高圧混合ガスを生成する高圧反応容器と、水素と二酸化炭素とを含む高圧混合ガスを相分離して水素濃度の高い高圧ガスを生成する気液分離器と、前記高圧反応容器で生成した高圧混合ガスを0.4MPa以上の全圧を保持したまま前記気液分離器に送給する高圧混合ガス送給通路とを備える高圧水素製造装置。
［１３］前記高圧反応容器は水素貯蔵剤を32〜120℃に加熱する加熱手段を有し、前記気液分離器は高圧混合ガスを-38〜32℃に保持する温度調節手段を有することを特徴とする［１２］に記載の高圧水素製造装置。 The present invention has been completed based on these findings, and according to the present invention, the following inventions are provided.
[1] A high-pressure mixed gas containing hydrogen and carbon dioxide with a total pressure of 7.3 MPa or more is generated from a hydrogen storage agent by a catalyst dehydrogenation reaction, and the total pressure of the generated high-pressure mixed gas is reduced to 0.4 MPa or less. A high-pressure hydrogen gas production method for producing a high-pressure gas having a high hydrogen concentration by phase-separating the high-pressure mixed gas without lowering.
[2] The hydrogen storage agent is one or more selected from formic acid and / or formate, methanol, ethanol, isopropanol, formaldehyde, acetaldehyde, glyoxal, and glyoxalic acid, according to [1] High pressure hydrogen gas production method.
[3] An organometallic complex in which the catalyst for generating high-pressure hydrogen contains one or more transition metals selected from iridium, rhodium, ruthenium, cobalt, osmium, nickel, iron, palladium, platinum, and gold Alternatively, the high-pressure gas production method according to [2], which is a salt of these complexes.
[4] The high-pressure gas production method according to [2] or [3], wherein a catalyst selected from those represented by the following formula (1) is used in the dehydrogenation reaction from the hydrogen storage agent: .

[In the above formula (1), M is Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A to F (one to three of A to F are Each may independently be a ligand containing halogen, phosphorus, nitrogen, carbon, oxygen, sulfur, or hydrogen as a coordinating atom, or 2 of A to F. One is a bidentate ligand coordinated to M or a tetradentate ligand structure containing M different from M, and m is a positive integer, 0, or negative Is an integer. ]
[5] The dehydrogenation reaction of the hydrogen storage agent uses a catalyst selected from those represented by the following formula (2) or (3): [3] or [4] High pressure gas production method.

[In Formula (2), M is Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A to B are each independently nitrogen, carbon, oxygen, or It is a ligand containing sulfur as a coordinating atom, or A and B are bidentate ligands coordinated to M, and L is an aromatic anion ligand or aromatic coordination When it is a ligand and has a substituent, one or a plurality of the ligands may be present, Z is an arbitrary ligand or does not exist, and m is a positive integer. , 0, or a negative integer. ]

[In Formula (3), M ^{1 to} M ² are each independently Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A ^{1 to} A ⁴ are respectively Independently, it is a ligand containing nitrogen, carbon, oxygen or sulfur as a coordinating atom, or A ^{1 to} A ⁴ are tetradentate ligands coordinated to M ¹ and M ² , L ^{1 and} L ² are each independently an aromatic anion ligand or an aromatic ligand, and when having a substituent, one or a plurality of the ligands may be present. , Z ¹ -Z ² are each independently any ligand or absent, and m is a positive integer, 0, or a negative integer. ]
[6] The catalyst according to [4] or [5], wherein a catalyst selected from those represented by the following formulas (4) to (10) is used for the dehydrogenation reaction of formic acid and / or formate. High pressure gas production method.

[In the above formulas (4) to (10),
In the formula, the 5-membered ring and the 6-membered ring have aromaticity, and A ^{1 to} A ⁴ are all nitrogen, or are each independently nitrogen or carbon, and X ¹ ~ X ¹⁰ are each independently nitrogen or carbon, and R ^{1 to} R ¹⁰ are each independently a hydrogen atom, alkyl group, phenyl group, nitro group, halogen group, sulfonic acid group (sulfo group), amino group. group, a carboxylic acid group (carboxyl group), hydroxy (-OH), an oxy anion group (-O ^-), or an alkoxy group (-OR) (provided that if X ⁱ is nitrogen, R of the position of the nitrogen ⁱ does not exist.) and L ^{1 to} L ² are each independently an aromatic anion ligand or an aromatic ligand, ligand may be a plurality, even one 1, Z ¹ to Z ² are each independently a any ligand, or absent , M is a positive integer, 0 or a negative integer,, M ¹ ~M ² are each independently a Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt , or Au, . ]
[7] The high-pressure hydrogen gas production according to any one of [1] to [6], wherein the dehydrogenation reaction of the hydrogen storage agent is performed in a high-pressure reaction vessel, and phase separation of the high-pressure mixed gas is performed in a gas-liquid separator. Method.
[8] The dehydrogenation reaction of the hydrogen storage agent is performed at a reaction temperature of 32 to 300 ° C., and the phase separation of the high-pressure mixed gas is performed at a phase separation temperature of −38 to 32 ° C. lower than the reaction temperature. The high-pressure hydrogen gas production method according to any one of [1] to [7].
[9] The high-pressure hydrogen gas production method according to [8], wherein the phase separation temperature is 0 to 32 ° C. and the dehydrogenation reaction temperature is 20 to 100 ° C. higher than the phase separation temperature.
[10] The method for producing high-pressure hydrogen gas according to any one of [1] to [9], wherein the supply of the hydrogen storage agent to the high-pressure reaction vessel is performed continuously or intermittently.
[11] After supplying a predetermined amount of hydrogen storage agent to a high-pressure reaction vessel having an atmospheric pressure inside, the hydrogen storage agent is heated to generate the high-pressure mixed gas, and the hydrogen storage agent is added until production of high-pressure hydrogen gas is stopped The high-pressure hydrogen gas production method according to any one of [1] to [10], wherein a high-pressure gas having a high hydrogen concentration is produced without being supplied.
[12] A high-pressure reaction vessel that generates a high-pressure mixed gas containing hydrogen and carbon dioxide having a total pressure of 7.3 MPa or more by dehydrogenation of the hydrogen storage agent, and a phase separation of the high-pressure mixed gas containing hydrogen and carbon dioxide Gas-liquid separator that generates a high-pressure gas with a high hydrogen concentration, and a high-pressure gas mixture that is supplied to the gas-liquid separator while maintaining a total pressure of 0.4 MPa or more with the high-pressure gas mixture generated in the high-pressure reactor A high-pressure hydrogen production apparatus comprising a supply passage.
[13] The high-pressure reactor has heating means for heating the hydrogen storage agent to 32 to 120 ° C, and the gas-liquid separator has temperature adjusting means for holding the high-pressure mixed gas at -38 to 32 ° C. The high-pressure hydrogen production apparatus according to [12], which is characterized in that.

In the conventional method, hydrogen stored in hydrocarbons, ammonia, biomass, hydrogen adsorbent, etc. had to be boosted using a compressor or compression process to supply it to a fuel cell vehicle, etc. In some cases, after obtaining hydrogen at a high temperature, there was no technique for purifying the hydrogen as it was, so the hydrogen was purified by the PSA method or the TSA method once after normal pressure, and then compressed by a compressor. However, high temperature energy is required in the dehydrogenation process, the structure of the compressor for compressing hydrogen is complicated, and a large amount of energy is required for that purpose.
In contrast, in the present invention, a high-pressure gas composed of carbon dioxide and hydrogen can be automatically obtained mainly from formic acid by a dehydrogenation reaction. Therefore, hydrogen can be purified by using the high-pressure gas. It is possible to supply hydrogen purified at a high pressure without necessarily using a purification method such as the PSA method or the TSA method, and without requiring a large amount of energy by a compressor, a compression process, or the like. In addition, it is not always necessary to use a compressor or compression process for compressing formic acid at a high pressure to supply formic acid to the dehydrogenation reaction vessel, and the dehydrogenation reaction temperature and the obtained gas pressure are adjusted to an appropriate range. Thus, a high-pressure gas with increased hydrogen purity can be produced by gas-liquid separation at a temperature near room temperature without requiring a low temperature such as deep cold separation or a large amount of energy therefor. Furthermore, since only hydrogen and carbon dioxide can be obtained from formic acid, carbon dioxide can also be obtained at the same time after hydrogen separation, and it can be used for another process without purification.

The drawing which shows the example of the high pressure hydrogen production system of the Example of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Drawing which shows the relationship between the setting pressure in reaction container in the high pressure hydrogen production of the Example of this invention, a gas generation rate, and the generation amount ratio of hydrogen and a carbon dioxide. The figure which shows the time change of the gas generation amount at the time of changing the setting pressure in reaction container, and a gas generation speed. The drawing which shows the time change of the molar ratio of hydrogen to carbon dioxide in the separated gas when the pressure during gas-liquid separation is 10 MPa and 20 MPa. Phase diagram of the hydrogen-carbon dioxide system. The figure which shows the time change of the gas generation amount at the time of changing dehydrogenation reaction temperature and a gas generation speed.

(Configuration of high-pressure hydrogen system)
An example of a system for producing high-pressure hydrogen is shown in a configuration as shown in FIG. 1, and mainly includes a dehydrogenation reaction section that generates high-pressure gas from a hydrogen storage agent, and carbon dioxide and hydrogen from the generated high-pressure gas. It is the system comprised from the gas-liquid separation part which isolate | separates.

(Hydrogen storage agent)
In the present invention, the hydrogen storage agent for obtaining the high-pressure hydrogen gas to be produced is not particularly limited as long as a gas containing high-pressure hydrogen can be generated, but is preferably formic acid and / or formate. In addition to formic acid and formate, alcohols such as methanol, ethanol and isopropanol, and formaldehyde, acetaldehyde, glyoxal and glyoxalic acid can be used as the hydrogen storage agent.
These hydrogen storage agents can be used as one kind or a mixture of two or more kinds, and can also be used as a solution containing a solvent or a dispersion containing a dispersant. The solvent or dispersion medium at that time may be solid or liquid. When formic acid or / and formate are used as the hydrogen storage agent, at least one solvent or dispersion medium selected from water, alcohol, hydrocarbon, etc. can be used, preferably water, ethylene glycol, polyethylene glycol Glycerin, methanol, ethanol, propanol, pentanol, and the like can be used, but water having low solubility in supercritical carbon dioxide, ethylene glycol, polyethylene glycol, glycerin, and more preferably water are more preferable. be able to. In addition, although alcohol is used also as a solvent or a dispersion medium, it can also be used as a hydrogen storage agent simultaneously.

(Examples of raw materials containing hydrogen storage agents)
In addition, treated products obtained by hydrocarbon reforming, coal dry distillation, coal gasification, etc., treated products containing solutions obtained by decomposition of plant-based biomass, treated products obtained from treatment of manure, etc. Since all of the processed products obtained by the decomposition treatment of waste plastics contain formic acid and / or formate, they can be used as raw materials (solutions, dispersions, etc.) containing hydrogen storage agents in the present invention. . In particular, as biomass, formic acid can be obtained by decomposing saccharides such as cellulose, glucose derived from hemicellulose, and fructose, and thus treated products containing hydrogen storage agents are useful when hydrogen is used as energy in the future. Can be used as a raw material.

(Acidity of formic acid and / or formate, counter cation)
When using formic acid or / and formate as a hydrogen storage agent as a solution, the acidity range is not particularly limited, but the acidity is preferably in the range of 1-9, more preferably 1-7. It is preferable to use in. In order to keep this acidity constant, formate can be used, but the counter cation of formate is not particularly limited. For example, as a cation, lithium ion, magnesium ion, sodium ion, potassium ion And various metal ions such as calcium ion, barium ion, strontium ion, yttrium ion, scandium ion, or lanthanoid ion, or ammonium ion, and alkylammonium ion such as tetramethylammonium and tetraethylammonium. These counter ions may be one type, or two or more types may coexist.

(Formic acid concentration)
In the present invention, when formic acid and / or formate as a hydrogen storage agent is used as a solution or a dispersion, if the total concentration of formic acid and formate is in the range of 1 μmol / L to 26 mol / L, high pressure Although it is possible to generate hydrogen, it is preferably in the range of 1 mmol / L or more and 26 mol / L or less, and more preferably in the range of 1 mol / L or more and 26 mol / L or less, more preferably high pressure. Hydrogen can be generated.

(Reactor for generating hydrogen)
In the present invention, the dehydrogenation reactor for generating high-pressure hydrogen gas to be produced can use a general pressure vessel such as stainless steel, but carbon monoxide is generated by contact of formic acid and metal. The container is preferably made of a material other than metal, such as resin, glass or ceramics. Further, it is preferable that the liquid contact part with formic acid is covered with resin, glass or ceramics. Can be used.

(Catalyst for generating hydrogen)
The catalyst for generating high-pressure hydrogen is preferably an organometallic complex composed of a transition metal. The transition metal species used for the catalyst for causing the dehydrogenation reaction is an organometallic complex containing at least one transition metal from iridium, rhodium, ruthenium, cobalt, osmium, nickel, iron, palladium, platinum or gold, or These salts can be used, but iridium, rhodium, ruthenium, and cobalt are preferably used, and iridium is more preferably used.

  The structure of the organometallic complex composed of the transition metal used as a catalyst is not particularly limited in solubility in a solution containing a hydrogen storage agent, but has a complex structure that dissolves in a solution containing a hydrogen storage agent. The complex structure is preferably a transition metal complex represented by the general formula (1), a complex metal complex, a tautomer or stereoisomer thereof, or a complex containing a salt thereof as a catalyst. Can do.

〔前式(１)において、Mは、Ir、Rh、Ru、Co、Os、Ni、Fe、Pd、Pt、またはAuであり、A〜F(A〜Fのうちの１つ〜３つは存在しなくても良い。)は、それぞれ独立に、ハロゲン、リン、窒素、炭素、酸素、硫黄、もしくは水素を配位原子として含む配位子であるか、または、A〜Fのうちの２つは、Mに配位する２座配位子であるか、もしくは、該Mとは別のMを含む４座配位子構造のものであり、mは、正の整数、0、または負の整数である。〕

[In the above formula (1), M is Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A to F (one to three of A to F are Each may independently be a ligand containing halogen, phosphorus, nitrogen, carbon, oxygen, sulfur, or hydrogen as a coordinating atom, or 2 of A to F. One is a bidentate ligand coordinated to M or a tetradentate ligand structure containing M different from M, and m is a positive integer, 0, or negative Is an integer. ]

  Specific examples include ruthenium chloride triphenylphosphine and chlororuthenium triphenylphosphine trisulfonate complexes. The structure of a metal complex that can be used as a highly selective catalyst is specifically described. As for the structure, a transition metal complex represented by general formula (2) or general formula (3), a complex metal complex, a tautomer or stereoisomer thereof, or a complex containing a salt thereof is used as a catalyst. it can.

〔前式(２)において、Mは、Ir、Rh、Ru、Co、Os、Ni、Fe、Pd、Pt、またはAuであり、A〜Bは、それぞれ独立に、窒素、炭素、酸素、もしくは硫黄を配位原子として含む配位子であるか、または、AとBは、Mに配位する２座配位子であり、Lは、芳香族性アニオン配位子、または芳香族性配位子であり、置換基を有している場合は、前記配位子は１つでも複数でも良く、Zは、任意の配位子であるか、または存在せず、mは、正の整数、0、または負の整数である。〕

〔前式(３)において、M¹〜M²は、それぞれ独立に、Ir、Rh、Ru、Co、Os、Ni、Fe、Pd、Pt、またはAuであり、A¹〜A⁴は、それぞれ独立に、窒素、炭素、酸素、もしくは硫黄を配位原子として含む配位子であるか、または、A¹〜A⁴は、M¹とM²に配位する４座配位子であり、L¹〜L²は、それぞれ独立に、芳香族性アニオン配位子、または芳香族性配位子であり、置換基を有している場合は、前記配位子は１つでも複数でも良く、Z¹〜Z²は、それぞれ独立に、任意の配位子であるか、または存在せず、mは、正の整数、0、または負の整数である。〕

[In Formula (2), M is Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A to B are each independently nitrogen, carbon, oxygen, or It is a ligand containing sulfur as a coordinating atom, or A and B are bidentate ligands coordinated to M, and L is an aromatic anion ligand or aromatic coordination When it is a ligand and has a substituent, one or a plurality of the ligands may be present, Z is an arbitrary ligand or does not exist, and m is a positive integer. , 0, or a negative integer. ]

[In Formula (3), M ^{1 to} M ² are each independently Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A ^{1 to} A ⁴ are respectively Independently, it is a ligand containing nitrogen, carbon, oxygen or sulfur as a coordinating atom, or A ^{1 to} A ⁴ are tetradentate ligands coordinated to M ¹ and M ² , L ^{1 and} L ² are each independently an aromatic anion ligand or an aromatic ligand, and when having a substituent, one or a plurality of the ligands may be present. , Z ¹ -Z ² are each independently any ligand or absent, and m is a positive integer, 0, or a negative integer. ]

  For example, more specifically, a transition metal complex represented by any one of the following formulas (4) to (10), a complex metal complex, a tautomer or stereoisomer thereof, or a complex containing a salt thereof, etc. It can be used as a catalyst.

〔前記式(４)〜(１０)において、
式中の５員環および６員環は、芳香族性を有するものであり、また、A¹〜A⁴は、いずれも窒素であるか、またはそれぞれ独立に、窒素もしくは炭素であり、X¹〜X¹⁰は、それぞれ独立に、窒素または炭素であり、R¹〜R¹⁰は、それぞれ独立に、水素原子、アルキル基、フェニル基、ニトロ基、ハロゲン基、スルホン酸基(スルホ基)、アミノ基、カルボン酸基(カルボキシル基)、ヒドロキシ基(-OH)、オキシアニオン基(-O^-)、またはアルコキシ基(-OR)(ただし、Xⁱが窒素である場合、その窒素の位置のRⁱは存在しない。)であり、L¹〜L²は、それぞれ独立に、芳香族性アニオン配位子、または芳香族性配位子であり、置換基を有している場合は、前記配位子は１つでも複数でも良く、Z¹〜Z²は、それぞれ独立に、任意の配位子であるか、または存在せず、mは、正の整数、0、または負の整数であり、M¹〜M²は、それぞれ独立に、Ir、Rh、Ru、Co、Os、Ni、Fe、Pd、Pt、またはAuである。〕

[In the above formulas (4) to (10),
In the formula, the 5-membered ring and the 6-membered ring have aromaticity, and A ^{1 to} A ⁴ are all nitrogen, or are each independently nitrogen or carbon, and X ¹ ~ X ¹⁰ are each independently nitrogen or carbon, and R ^{1 to} R ¹⁰ are each independently a hydrogen atom, alkyl group, phenyl group, nitro group, halogen group, sulfonic acid group (sulfo group), amino group. group, a carboxylic acid group (carboxyl group), hydroxy (-OH), an oxy anion group (-O ^-), or an alkoxy group (-OR) (provided that if X ⁱ is nitrogen, R of the position of the nitrogen ⁱ does not exist.) and L ^{1 to} L ² are each independently an aromatic anion ligand or an aromatic ligand, ligand may be a plurality, even one 1, Z ¹ to Z ² are each independently either any ligand, or absent , M is a positive integer, 0 or a negative integer,, M ¹ ~M ² are each independently a Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt , or Au, . ]

In the transition metal complexes represented by the general formulas (1) to (10), the counter ions are not particularly limited, but examples of the anions include hexafluorophosphate ions (PF6 ⁻ ), tetrafluoroborate ions ( BF4 @ ^-), hydroxide ions (OH ^-), acetate ion, carbonate ion, phosphate ion, sulfate ion, nitrate ion, halide ion (e.g. fluoride ion (F ^-), chloride ion (Cl ^-), bromide ion (Br ^-), iodide ion (I ^-), etc.), hypohalous acid ion (e.g. hypofluorite ion, hypochlorite ion, hypobromous acid ion, hypoiodous ion), Halogenite ion (for example, fluorite ion, chlorite ion, bromite ion, iodate ion, etc.), halogenate ion (for example, fluorate ion, chlorate ion, bromate ion, iodate ion, etc.) , Perhalogenated acid One (e.g. perfluorinated acid ion, perchloric acid ion, perbromic acid ion, periodic acid ion, etc.), trifluoromethanesulfonate ion (OSO ₂ CF ₃ ^-), tetrakis pentafluorophenyl borate ion [B (C ₆ F _{5) 4} ^-], and the like. The cation is not particularly limited, but various metal ions such as lithium ion, magnesium ion, sodium ion, potassium ion, calcium ion, barium ion, strontium ion, yttrium ion, scandium ion, lanthanoid ion, hydrogen ion, etc. Can be mentioned. These counter ions may be of one type, but two or more types may coexist. However, this description is only an example of a possible mechanism and does not limit the present invention.

(Hydrogen generation method)
In the present invention, the dehydrogenation reaction for obtaining the high-pressure hydrogen gas to be produced can be suitably performed by either a batch method or a flow method. In the case of the batch type, high-pressure hydrogen gas is generated in the reaction vessel, and the obtained gas can be transferred to a gas-liquid separator at the subsequent stage. In the flow method, since the reaction start temperature is 50 ° C. or higher, high-pressure gas can be generated by changing the temperature while flowing with a pump, and it is transferred to the gas-liquid separator at the subsequent stage as it is. Purification can be performed.

(Hydrogen generation temperature)
In the present invention, the dehydrogenation reaction for obtaining the high-pressure hydrogen gas to be produced is carried out by using a gas-liquid separator at a later stage to convert hydrogen and carbon dioxide if the mixed gas of hydrogen and carbon dioxide purified from formic acid is in a uniform phase state. Can be separated. That is, if a dehydrogenation reaction is carried out at a temperature higher than the critical temperature for forming a uniform phase, a uniform mixed gas can be obtained, and hydrogen can be purified in a subsequent stage while maintaining a high pressure state. That is, if it is carried out at -38 ° C or higher where a supercritical phase of a mixed gas of hydrogen and carbon dioxide appears, high-pressure hydrogen can be suitably produced, but further, it is carried out in the range of 32 ° C or higher of the critical temperature of carbon dioxide. More preferably, it can be carried out at a temperature of 50 ° C. or higher at which the dehydrogenation reaction proceeds. In particular, in order to perform gas-liquid separation in the latter stage efficiently from low temperature to near room temperature (-38 ° C to 32 ° C) without significantly reducing the pressure at the time of generation, the hydrogen generation temperature is from -38 ° C to 32 ° C. It is desirable that the temperature be higher than the critical temperature locus.

(Gas pressure at the time of generation)
In the present invention, the high-pressure gas containing hydrogen and carbon dioxide generated from formic acid (which is a gas when converted to normal temperature and normal pressure) is 0.1 MPa or more, and the solid-gas is separated by a gas-liquid separator at the subsequent stage. Hydrogen can be purified by separation, but since a gas-liquid phase does not appear at a maximum critical pressure of 200 MPa or more, it is preferably within the range. That is, high-pressure hydrogen purified by a gas-liquid separator in the subsequent stage can be produced in the range of normal pressure (0.1 MPa) to 200 MPa. More preferably, if the triple point pressure is 0.4 MPa or more and 200 MPa or less, carbon dioxide can be liquefied and hydrogen can be separated as a gas. Most preferably, the critical pressure during gas purification is 7.3 MPa. If it is 200 MPa or less, hydrogen and carbon dioxide become a uniform fluid at the time of generation, and gas-liquid separation in the subsequent stage is easy to perform.

(Gas-liquid separator)
In the present invention, by performing gas-liquid separation in a high pressure state, carbon dioxide is liquefied from a mixed gas of hydrogen and carbon dioxide to obtain purified carbon dioxide as a liquid, and purified hydrogen as a gas. it can. In the gas-liquid separation, the dehydrogenation reactor can be used as a gas-liquid separator as it is, but it is preferable to carry out separation and purification with a gas-liquid separator provided separately.

(Gas-liquid separator temperature)
In addition, the final point of the vapor-liquid equilibrium line of pure carbon dioxide is the critical point of pure carbon dioxide, and the critical point changes as the composition changes as hydrogen is added to the carbon dioxide (critical trajectory). That is, under conditions below the critical point and above the vapor pressure of pure carbon dioxide, the mixture has a gas phase and a liquid phase, but the carbon dioxide becomes a solid below a certain temperature, so the mixture no longer has a critical point. (Upper critical point), it becomes a gas-solid mixture through gas-liquid-solid equilibrium (FIG. 5). Therefore, the temperature range in which hydrogen purification can be performed only needs to be a temperature at which carbon dioxide is liquefied or solidified, and may be a boiling point of hydrogen (−252 ° C.) or higher and a critical temperature of carbon dioxide (32 ° C.) or lower. Preferably, if it is in the range of the triple point (-57 ° C) or higher and the critical temperature of carbon dioxide (32 ° C) or lower, a gas-liquid phase appears, so that separation and purification are possible, and more preferably the highest critical point (upper critical endpoint (upper critical endpoint) ) Temperature (-38 ° C) or higher and the critical temperature of carbon dioxide critical point (32 ° C) or lower, the supercritical gas mixture is converted into a gas-liquid phase, gas-liquid separated, and hydrogen and carbon dioxide Carbon can be separated.

(Gas-liquid separator pressure)
In the present invention, the pressure during the separation of hydrogen and carbon dioxide in the gas-liquid separator may be the same as the high-pressure state when the high-pressure mixed gas is generated. It is also possible to set or reduce the pressure to a pressure lower than the time. If the pressure of the gas-liquid separator in the present invention is within the range of normal pressure (0.1 MPa) to 200 MPa, hydrogen can be separated and purified by the gas-liquid separator, but more preferably pure carbon dioxide. Carbon dioxide can be liquefied and hydrogen can be separated at the same time as long as the pressure at the triple point (−38 ° C., 0.4 MPa) is 0.4 MPa or more and 200 MPa or less. The temperature at that time is from low temperature to around room temperature (−38 ° C. to 32 ° C.), and gas-liquid separation is possible in this region, and the hydrogen concentration can be further increased.

  Next, the present invention will be specifically described based on examples and reference examples, but the present invention is not limited to the following examples.

(Reference Example 1)
[High pressure mixed gas generation]
Attach a pipe with a valve and a pressure gauge to a 26 mL stainless steel pressure vessel, put 20 mL (0.32 mol) of 16M formic acid, 2.5 mg (4.0 μmol) of the catalyst shown in formula (11), and normal temperature and normal pressure (25 ° C, Carbon dioxide was circulated at 0.1 MPa) to replace the air in the container. Thereafter, the valve was closed and heated to 80 ° C. in a water bath while shaking to start the dehydrogenation reaction, and the reaction was continued until the pressure became constant. As a result, it was found that the pressure increased to 140 MPa, and further, it was confirmed by gas chromatography that the gas components were 1: 1 hydrogen and carbon dioxide. Furthermore, although the partial pressure of hydrogen was 70 MPa, it was confirmed that by further gas-liquid separation of the generated mixed gas, purified high-pressure hydrogen up to about 70 MPa was finally obtained. At this time, it was confirmed that carbon monoxide was not contained in the gas phase mainly composed of hydrogen.

(Reference Example 2)
[Dehydrogenation reaction]
A high-pressure hydrogen gas production test apparatus is shown in FIG. In a 50 mL stainless steel autoclave (Fig. 1, (8) high-pressure reactor), 40 mL (6.32 mmol) of 16M (15.8M) formic acid and 2.6 mg (4.1 μmol) of the catalyst shown in formula (11) are placed at room temperature. Carbon dioxide was circulated at a pressure (25 ° C., 0.1 MPa) to replace the air in the container. Thereafter, (6) the valve was closed, and the mixture was heated to 80 ° C. with a water bath while stirring with a magnetic stirrer to initiate the dehydrogenation reaction. (16), (24) and (26) Set the pressure adjustment valve to a pressure of 0.1 MPa to 40 MPa, and after starting the reaction, when the total pressure reaches the specified pressure, The rate of occurrence was measured. First, close (19) SV-7 (stop valve), (20) SV-8 (stop valve), open (18) SV-6 (stop valve), and (21) gas-liquid separation container (50 mL , 100 MPa, −50 to 35 ° C.) As a result of the measurement, it was confirmed that the obtained gas component was approximately 1: 1 of hydrogen and carbon dioxide (FIG. 2). Further, the gas generation rate obtained at each pressure was returned to normal temperature and pressure. The results are shown in FIG. At that time, if the dehydrogenation reaction temperature is 80 ° C, 1.46 L / hour at normal pressure, 1.54 L / hour at 1 MPa, 1.13 L / hour at 5 MPa, 0.84 L / hour at 10 MPa, 0.84 L / hour at 30 MPa At 0.23 L / hour and 40 MPa, 0.08 L / hour, it was found that the generated gas velocity becomes slower as the pressure increases (FIG. 3).

Example 1
[Gas-liquid separation pressure of high-pressure mixed gas]
In Reference Example 2, it was found that high-pressure hydrogen and carbon dioxide of about 1: 1 were obtained, so in order to examine the feasibility of hydrogen purification when a (21) gas-liquid separator was connected in the latter stage, (18) Close the SV-6 (stop valve), open (20) SV-8 (stop valve), (19) SV-7 (stop valve), and mix the high pressure obtained from the device of Reference Example 2 The gas was led to (21) gas-liquid separation vessel (50 mL, 100 MPa, -50 to 35 ° C.). Next, the high-pressure mixed gas was subjected to gas-liquid separation at each pressure while maintaining the temperature of the gas-liquid separation container at room temperature (25 ° C.), and the components of the gas phase were measured by gas chromatography. As a result, when the pressure was 10 MPa, the ratio of hydrogen to carbon dioxide was approximately 1: 1. However, when the pressure was 20 MPa, the gas component at 3: 2 and 30 MPa had a ratio of hydrogen to carbon dioxide of approximately It was confirmed that the ratio was 3: 1 (75% hydrogen, 25% carbon dioxide) (FIG. 4). In any case, carbon monoxide was not contained, and the obtained gas was consistent with the hydrogen-carbon dioxide phase diagram (FIG. 5), and it was found that the corresponding gas was obtained.

(Example 2)
[Gas-liquid separation temperature of high pressure mixed gas]
Next, in the same apparatus as in Example 1, with the pressure for gas-liquid separation kept constant at 30 MPa, (21) the temperature of the gas-liquid separation container was set in the range of 0 ° C to 30 ° C, and each temperature Gas-liquid separation was performed and gas components were measured. As a result, at a temperature of 25 ° C. (below the critical temperature of 32 ° C.), at 10 MPa, the ratio of hydrogen to carbon dioxide is slightly increased to 1.2, whereas at 20 MPa, the hydrogen concentration is slightly increased. It was found that the hydrogen concentration further increased (FIG. 4). As a result of measuring the concentration of hydrogen and carbon dioxide at 30 MPa, when the temperature is 35 ° C, which is higher than the critical temperature, the ratio of hydrogen to carbon dioxide is approximately 1.0, and the gas-liquid separator temperature is 1 ° C. 1.5, a gas containing 59% hydrogen, and further -15 ° C, it was found to be 2.24, a high-pressure gas containing 69% hydrogen, and it is possible to purify hydrogen by pressure and temperature. It was confirmed. Also in this example, carbon monoxide was not contained. From this, by adjusting the state of one (21) gas-liquid separation container (adjusted in the range of 50 mL, ~ 100 MPa, -50 ° C to 32 ° C), the high-pressure gas obtained by the dehydrogenation reaction was directly converted into hydrogen. It was found that the gas and liquid can be separated into more purified hydrogen and purified liquefied carbon dioxide.

Example 3
[Adjustment of high-pressure hydrogen production rate]
Next, the reaction temperature of high-pressure hydrogen obtained by dehydrogenation was examined using the same apparatus as in Example 2 (FIG. 6). As a result, it was found that when changing from 80 ° C. → 90 ° C. → 50 ° C. → 60 ° C. → 70 ° C. → 80 ° C., high pressure gas of 10 MPa or more can be generated at 50 ° C. or higher. Furthermore, these high-pressure gases are approximately 1: 1 in hydrogen and carbon dioxide, and as in Example 2, hydrogen and carbon dioxide can be separated based on the phase diagram by adjusting the temperature of the gas-liquid separator. It was confirmed.

  In the high-pressure hydrogen production method and production system of the present invention, carbon dioxide and hydrogen obtained by dehydrogenating formic acid become a high-pressure gas of 100 MPa or more, and further, the purity of the gas is high by using a gas-liquid separator without greatly reducing the pressure. High pressure and high pressure hydrogen can be supplied easily. Many high-pressure hydrogen supply systems purify hydrogen through membrane separation at low pressure and then compress it with a compressor to supply high-pressure hydrogen, but these systems do not require these equipment and processes. Therefore, a simple system can be assembled and less energy is required for driving. In particular, since formic acid is used as the hydrogen storage agent, it is driven at a low temperature of 100 ° C. or lower, and therefore a safe system can be constructed in the future when building an energy system using hydrogen as energy. In addition, because of its simple structure, it is possible to reduce the size, and it is easy to deal with a wide range of scales from large hydrogen supply systems to small supply systems.

Claims (13)

  Without degrading the total pressure of the generated high-pressure mixed gas to 0.4 MPa or less by generating a high-pressure mixed gas containing hydrogen and carbon dioxide with a total pressure of 7.3 MPa or more from the hydrogen storage agent using a catalyst. A high-pressure hydrogen gas production method for producing a high-pressure gas having a high hydrogen concentration by phase-separating the high-pressure gas mixture.   The high-pressure hydrogen according to claim 1, wherein the hydrogen storage agent is one or more selected from formic acid or / and formate, methanol, ethanol, isopropanol, formaldehyde, acetaldehyde, glyoxal, and glyoxalic acid. Gas production method.   An organometallic complex containing one or more transition metals selected from iridium, rhodium, ruthenium, cobalt, osmium, nickel, iron, palladium, platinum, and gold, or a complex thereof, for generating high-pressure hydrogen The high-pressure gas production method according to claim 2, wherein The high-pressure gas production method according to claim 2 or 3, wherein a catalyst selected from those represented by the following formula (1) is used in the dehydrogenation reaction from the hydrogen storage agent.

[In the above formula (1), M is Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A to F (one to three of A to F are Each may independently be a ligand containing halogen, phosphorus, nitrogen, carbon, oxygen, sulfur, or hydrogen as a coordinating atom, or 2 of A to F. One is a bidentate ligand coordinated to M or a tetradentate ligand structure containing M different from M, and m is a positive integer, 0, or negative Is an integer. ] The method for producing a high-pressure gas according to claim 3 or 4, wherein a catalyst selected from those represented by the following formula (2) or formula (3) is used in the dehydrogenation reaction from the hydrogen storage agent. .

[In Formula (2), M is Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A to B are each independently nitrogen, carbon, oxygen, or It is a ligand containing sulfur as a coordinating atom, or A and B are bidentate ligands coordinated to M, and L is an aromatic anion ligand or aromatic coordination When it is a ligand and has a substituent, one or a plurality of the ligands may be present, Z is an arbitrary ligand or does not exist, and m is a positive integer. , 0, or a negative integer. ]

[In Formula (3), M ^{1 to} M ² are each independently Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt, or Au, and A ^{1 to} A ⁴ are respectively Independently, it is a ligand containing nitrogen, carbon, oxygen or sulfur as a coordinating atom, or A ^{1 to} A ⁴ are tetradentate ligands coordinated to M ¹ and M ² , L ^{1 and} L ² are each independently an aromatic anion ligand or an aromatic ligand, and when having a substituent, one or a plurality of the ligands may be present. , Z ¹ -Z ² are each independently any ligand or absent, and m is a positive integer, 0, or a negative integer. ] 6. The high-pressure gas production method according to claim 4, wherein a catalyst selected from those represented by the following formulas (4) to (10) is used for the dehydrogenation reaction of formic acid and / or formate. .

[In the above formulas (4) to (10),
In the formula, the 5-membered ring and the 6-membered ring have aromaticity, and A ^{1 to} A ⁴ are all nitrogen, or are each independently nitrogen or carbon, and X ¹ to X ¹⁰ is each independently nitrogen or carbon, and R ^{1 to} R ¹⁰ are each independently hydrogen atom, alkyl group, phenyl group, nitro group, halogen group, sulfonic acid group (sulfo group), amino group , A carboxylic acid group (carboxy group), a hydroxy group, an oxyanion group, or an alkoxy group (provided that when X ⁱ is nitrogen, there is no R ^{i at the} nitrogen position), L ^{1 to} L ² Are each independently an aromatic anion ligand or an aromatic ligand, and when having a substituent, one or a plurality of the ligands may be used, and Z ^{1 to} Z ² are each independently either any ligand, or not present, m is a positive integer , 0 or a negative integer,, M ¹ ~M ² are each independently Ir, Rh, Ru, Co, Os, Ni, Fe, Pd, Pt , or Au,. ]   The method for producing high-pressure hydrogen gas according to any one of claims 1 to 6, wherein a dehydrogenation reaction of the hydrogen storage agent is performed in a high-pressure reaction vessel, and phase separation of the high-pressure mixed gas is performed in a gas-liquid separator.   The dehydrogenation reaction of the hydrogen storage agent is performed at a reaction temperature of 32 to 300 ° C, and the phase separation of the high-pressure mixed gas is performed at a phase separation temperature of -38 to 32 ° C lower than the reaction temperature. The high-pressure hydrogen gas production method according to any one of 1 to 7.   The method for producing high-pressure hydrogen gas according to claim 8, wherein the phase separation temperature is 0 to 32 ° C and the dehydrogenation reaction temperature is 20 to 100 ° C higher than the phase separation temperature.   The method for producing high-pressure hydrogen gas according to any one of claims 1 to 9, wherein the hydrogen storage agent is supplied to the high-pressure reaction vessel continuously or intermittently.   After supplying a predetermined amount of hydrogen storage agent to a high-pressure reaction vessel having an atmospheric pressure inside, the hydrogen storage agent is heated to produce the high-pressure mixed gas, and additional hydrogen storage agent is supplied until production of high-pressure hydrogen gas is stopped. The high-pressure hydrogen gas production method according to any one of claims 1 to 10, wherein a high-pressure gas having a high hydrogen concentration is produced.   A high-pressure reaction vessel that generates a high-pressure mixed gas containing hydrogen and carbon dioxide with a total pressure of 7.3 MPa or more by dehydrogenation reaction of the hydrogen storage agent, and a high-pressure mixed gas containing hydrogen and carbon dioxide are phase-separated into hydrogen. A gas-liquid separator that generates high-concentration high-pressure gas, and a high-pressure mixed gas supply passage that supplies the high-pressure mixed gas generated in the high-pressure reaction vessel to the gas-liquid separator while maintaining a total pressure of 0.4 MPa or more. And a high-pressure hydrogen production apparatus.   The high-pressure reactor has heating means for heating the hydrogen storage agent to 32 to 120 ° C., and the gas-liquid separator has temperature control means for holding the high-pressure mixed gas at −38 to 32 ° C. The high pressure hydrogen production apparatus according to claim 12.

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