JP7161778B2 - Hydrogen carrier and its manufacturing method - Google Patents

Description

The present invention relates to a hydrogen carrier that is excellent in hydrogen storage and release characteristics and is safe, and is particularly useful as a hydrogen terminal carrier for delivering hydrogen from hydrogen stations to end users, and a method for producing the same.

In recent years, due to the emergence of problems such as global warming, attention has been paid to renewable energy as an alternative to fossil fuels. For example, fuel cell vehicles have been developed to replace gasoline vehicles, and household fuel cells have been developed.

However, hydrogen, which is the fuel for fuel cells, is highly reactive and dangerous, and because it is a gas at normal temperature and pressure, it is less efficient than fossil fuels such as gasoline and kerosene, which are liquid at normal temperature and pressure. There is the problem of low

High-pressure hydrogen cylinders are the simplest means for increasing the transportation efficiency of hydrogen. However, high-pressure hydrogen cylinders have problems such as leaks and explosions, and their safety is low. Therefore, organic hydrides are being studied as hydrogen carriers. Organic hydrides include, for example, methylcyclohexane and decalin obtained by reducing toluene and naphthalene with hydrogen. Methylcyclohexane and decalin are safer than hydrogen and are excellent in handleability because they are liquids at normal temperature and normal pressure. However, when organic hydride is oxidized to extract hydrogen, a special catalyst and high temperature conditions are required. Organic hydrides are therefore not suitable as hydrogen terminal carriers, for example for delivering hydrogen from hydrogen stations to end users.

It is also being considered to reduce nitrogen with hydrogen to produce ammonia, transport this ammonia, and extract hydrogen by oxidizing the ammonia at the time of use. However, a catalyst and high energy are required to extract hydrogen from ammonia, and ammonia is by no means safe, and is not easy to handle because it is a gas at normal temperature and pressure and has a high vapor pressure. .

Therefore, hydrogen hydrate is expected as a hydrogen carrier, especially as a hydrogen terminal carrier. Hydrogen hydrate is extremely safe, and hydrogen is easily released simply by leaving it under normal temperature and normal pressure. However, in general, the formation of hydrogen hydrate requires low temperature and high pressure conditions such as −24° C. and 100 MPa. Therefore, in Patent Document 1, an aqueous solution of a hydrate-forming auxiliary such as tetrahydrofuran that shifts the phase equilibrium pressure and temperature of hydrogen hydrate to the normal pressure/normal temperature side is added through a porous filter to, for example, 5 MPa at less than 7 ° C. of hydrogen is disclosed. The ease with which hydrates are formed varies depending on the types of guest molecules to be clathrated.

In addition, hydrogen hydrate has the disadvantage that the storage amount of hydrogen is small because hydrogen to be occluded is gaseous at normal temperature and pressure. Therefore, Patent Document 2 describes a method of producing hydrogen hydrate using an aqueous solution of acetone or the like at a low temperature of -30° C. to -1° C. and a pressure of 3 to 20 MPa. Patent Document 3 discloses a method in which an aqueous solution of tetrahydrofuran or acetone is absorbed into the voids in the carbon nanotube beads, and hydrogen at 120 to 200 atm is absorbed into the hydrate cage at a temperature below the freezing point.

Japanese Unexamined Patent Application Publication No. 2012-236740 JP 2008-285341 A JP 2007-272781 A

As described above, various methods for producing hydrogen hydrate have been developed, but generally, hydrogen at a pressure of several tens of atmospheres or more (several MPa or more) is occluded in a hydrate cage.
Therefore, the present invention can be produced using hydrogen at normal pressure or relatively normal pressure, is excellent in hydrogen storage characteristics, and is also excellent in hydrogen release characteristics and is safe. An object of the present invention is to provide a hydrogen carrier useful as a terminal carrier and a method for producing the same.

The present inventors have made intensive studies to solve the above problems. As a result, it was found that a large amount of hydrogen can be easily occluded in a hydrate cage at normal pressure or a pressure relatively close to normal pressure by using hollow particles having pores in the outer shell, and completed the present invention. did.
The present invention is shown below. In addition, hereinafter, hollow particles having pores in the outer shell may be abbreviated as “hollow particles with pores”.

[1] including hollow particles and hydrogen hydrate,
The outer shell of the hollow particles has pores,
A hydrogen carrier, wherein the hydrogen hydrate is contained in the hollow particles.

[2] The hydrogen carrier according to [1] above, wherein the hollow particles have a particle diameter of 1000 μm or less.

[3] The hydrogen carrier according to [1] or [2] above, wherein the ratio of the total open area of the pores to the surface area of the hollow particles is 0.5% or more and 10% or less.

[4] The hydrogen carrier according to any one of [1] to [3] above, wherein the hollow particles are hollow silica particles or hollow zeolite particles.

[5] The hydrogen carrier according to any one of [1] to [4] above, wherein the hydrogen hydrate contains a hydrate-forming aid in addition to water and hydrogen.

[6] A method for producing a hydrogen carrier, comprising:
A step of encapsulating water or an aqueous solution of a hydrate-forming aid inside hollow particles whose outer shells have pores;
cooling the hollow particles enclosing the water or the aqueous hydrate-forming aid solution to form a hydrate cage;
A method comprising the step of causing hydrogen to be occluded in said hydrate cage by contacting said hydrate cage with hydrogen.

[7] The method according to [6] above, wherein the pressure of the hydrogen is normal pressure or more and less than 1000 kPa.

[8] A step of producing a hydrogen carrier by the method described in [6] or [7] above;
A method for transporting hydrogen, comprising the step of transporting the hydrogen carrier.

The hydrogen carrier of the present invention can store a large amount of hydrogen, and the main constituents are only inorganic porous hollow particles and hydrogen hydrate. It is particularly useful as a hydrogen terminal carrier because hydrogen can be easily released by raising the temperature to . Moreover, the hydrogen carrier of the present invention can be efficiently produced without requiring extremely low-temperature or high-pressure hydrogen. Thus, for example, it does not require large-scale installations for its production, so that it can be produced in hydrogen stations for supplying hydrogen to end users. Therefore, the present invention is industrially extremely useful as a means of promoting the practical use of renewable energy sources such as fuel cells that use hydrogen as a main raw material.

FIG. 1 is an enlarged photograph of a perforated hollow particle according to the present invention. FIG. 2 is a schematic diagram of the equipment used to produce the hydrogen carrier according to the invention. FIG. 3 is a graph showing a cooling curve of the temperature in the vicinity of the hollow particles when manufacturing the hydrogen carrier according to the present invention.

The hydrogen carrier of the present invention comprises perforated hollow particles and hydrogen hydrates. The material of the perforated hollow particles is not particularly limited as long as the particles are safe, and the particles are sufficiently small and hollow. Examples include silica (SiO ₂ ) and zeolite. Although zeolite has silicon dioxide as its main skeleton, it has a crystal structure in which part of silicon is substituted with aluminum or the like.

The porous hollow silica particles can be easily produced by a conventional method, for example, the method described in WO2015/025529 or JP-A-2017-3148. That is, W /O emulsion is obtained. The size of the hollow particles can be adjusted by adjusting the size of the droplets in the emulsion. The droplet size can be adjusted by, for example, the type and amount of surfactant, stirring power, and the like. Also, the ratio of the pore area to the surface area of the hollow particles can be adjusted by adjusting the ratio of the pore-forming material used to the raw material of the hollow particles. Next, the W/O/W emulsion is prepared by adding the W/O emulsion to an aqueous phase such as an aqueous ammonium hydrogen carbonate solution and vigorously stirring the mixture. At this time, polysiloxane and silica containing a pore-forming material are formed in the oil phase. The formed particles are separated from the liquid phase, dried, and then calcined at about 350° C. or higher and 800° C. or lower to produce porous hollow silica particles.

The perforated hollow zeolite particles can be easily produced by a conventional method such as the method described in JP-A-2009-269788. That is, a core zeolite containing a metal such as aluminum is formed, zeolite crystals not containing the metal are grown to form a shell, the metal is removed, and the core zeolite is decomposed with a silica decomposing agent to obtain an active material. Hollow-porous zeolite particles can be made.

The size, eg diameter, of the perforated hollow particles is an important parameter for the present invention. The present invention has been devised in consideration of the fact that hydrogen is absorbed in the hydrate cage existing in the place where hydrogen diffuses due to the diffusion phenomenon of hydrogen in water. That is, in view of the fact that hollow particles having a diameter exceeding the diffusion distance of hydrogen have a wasteful area of water in which hydrogen absorption does not occur in the first place, the present invention proposes to enclose water in perforated hollow particles having an appropriate diameter. By arranging the water containing the hydrate cages within a distance where the hydrogen entering from the pores of the outer shell can diffuse, efficient hydrogen absorption is realized. Since the diffusion coefficient of hydrogen in water is approximately 7.44×10 ⁻⁹ m ² /sec, the diffusion distance as a function of time is roughly calculated to have the following relationship: .
Time Hydrogen diffusion distance 1 minute 94 μm
10 minutes 298 μm
30 minutes 517 μm
That is, since it diffuses to about 517 μm in about 30 minutes, the diameter is about 1000 μm.

Therefore, the size of the perforated hollow particles may be appropriately adjusted in consideration of the time required for hydrogen diffusion. The smaller the perforated hollow particles, the shorter the hydrogen absorption in the hydrate cage. If the diameter is 1000 μm or less, it can be said that the time efficiency of hydrogen absorption is sufficiently high. On the other hand, it may be difficult to manufacture hollow particles that are excessively small, and the hydrogen storage capacity per unit weight of the hydrogen carrier may be rather small. The diameter is more preferably 10 μm or more, more preferably 500 μm or less or 100 μm or less, even more preferably 50 μm or less or 30 μm or less, and particularly preferably 25 μm or less. The diameter of the hollow particles can be measured using a laser diffraction particle size distribution analyzer, a scanning electron microscope, or the like. Further, the hollow particles used may contain hollow particles exceeding the above range as long as the problems of the present invention can be solved.

The hollow particles used in the present invention have pores in their outer shells. Hydrogen can be occluded in the hydrate cages contained in the hollow particles through such pores. Such a pore diameter can be, for example, 10 nm or more and 500 nm or less in equivalent circle diameter. If the equivalent circle diameter is 500 nm or less, sufficient strength of the hollow particles can be maintained regardless of the existence of pores, and if it is 10 nm or more, sufficient hydrogen storage efficiency can be ensured. The diameter is preferably 50 nm or more, more preferably 100 nm or more, and preferably 400 nm or less. Moreover, the ratio of the total area of the pore openings to the surface area of the hollow particles (including the pore portions) is preferably 0.5% or more and 10% or less. If the ratio is 0.5% or more, sufficient hydrogen storage efficiency can be ensured, and if the ratio is 10% or less, the strength of the hollow particles can be sufficiently maintained. The circle-equivalent diameter of the pores and the ratio of the open area of the pores can be determined by a conventional method. For example, it is possible to photograph a representative hollow particle under magnification with a scanning electron microscope (SEM), import the obtained image data into image analysis software, and obtain the image data using the image analysis software.

The hydrogen carriers of the present invention are perforated hollow particles containing hydrogen hydrate therein. In the hydrogen carrier of the present invention, since the hydrogen hydrate is enclosed in the perforated hollow particles, not only can it be produced under milder conditions, but the hydrogen hydrate may be stabilized.

Hydrogen hydrate refers to a hydrate cage in which hydrogen is clathrated. A hydrate cage is a solid crystal constructed by water molecules, and three types of cubic structure type I and structure II, and hexagonal structure H type are known. Each structure contains an S-cage, which is a dodecahedron containing 12 regular pentagons composed of 5 water molecules. Hereinafter, a regular x-sided y-hedron is represented by xy. For example, S-cage is represented by 5 ¹² . Structure type I includes an M-cage (5 ¹² 6 ² ) composed of a 12-sided pentagon and a two-sided hexagon in addition to the S-cage, and structure type II includes an S-cage plus , L-cage (5 ¹² 6 ⁴ ), and structure H type contains S′-cage (4 ³ 5 ⁶ 6 ³ ) and U-cage (5 ¹² 6 ⁸ ) in addition to S-cage. It is known that the crystal structure of hydrate cages is determined mainly by the size and shape of the enclosed guest molecules, and undergoes phase transitions depending on temperature and pressure. It has also been reported that two hydrogen molecules are included in the S-cage and four hydrogen molecules are included in the L-cage.

Cryogenic temperatures and high pressures of 100 MPa or higher are required to stably hold hydrogen hydrate. However, the use of a hydrate formation aid allows the formation conditions of the hydrate cage to be at relatively higher temperatures and relatively lower pressures. Examples of hydrate-forming aids include, but are not limited to, tetrahydrofuran, tetrahydrofurfuryl alcohol, 1,3-dioxolane, 2,5-dihydrofuran, tetrahydrofuran sulfonic acid, tetrahydrofuran and its derivatives; tetrabutylammonium bromide , quaternary ammonium salts such as tetrabutylammonium chloride, tetrabutylammonium hydroxide, tetrabutylammonium fluoride, tetramethylammonium hydroxide; phosphates such as tetraphenylphosphonium bromide; carbonization of propane, methane, cyclopentane, etc. hydrogens; ketones such as acetone; and epoxies such as propylene oxide.

The amount of the hydrate-forming adjuvant to be used may be adjusted as appropriate. can. If the ratio is 1% by mass or more, the action of the hydrate-forming aid is exhibited more reliably. On the other hand, if the ratio is 40% by mass or less, the hydrogen storage capacity can be secured more reliably. The ratio is more preferably 2% by mass or more, even more preferably 5% by mass or more, and more preferably 15% by mass or less. More specifically, the amount to be used may be determined in consideration of the water solubility of the hydrate-forming adjuvant. For example, the solubility of tetrabutylammonium bromide in water at room temperature is about 40% by mass, and the solubility of tetrahydrofuran in water is about 19%.

In the case of hydrogen hydrate, if a hydrate forming aid is used, the hydrogen storage capacity is reduced by that amount, and not all hydrate cages store hydrogen. Actually, the hydrogen absorption amount of the hydrogen hydrate obtained under hydrogen of 100 atm was about 0.10% by mass. However, according to experimental findings by the present inventors, a hydrogen storage capacity of approximately 0.60% by mass was achieved despite the use of normal pressure hydrogen. As described above, in the present invention, although hydrogen is used at normal or relatively normal pressure, a hydrogen storage capacity six times or more than that obtained using hydrogen at 100 atm was achieved.

A method for producing a hydrogen carrier according to the present invention will be described below.
1. Step of Enclosing Water or Aqueous Solution In this step, water or an aqueous solution of a hydrate cage-forming adjuvant is enclosed inside the perforated hollow particles. When an aqueous hydrate cage-forming auxiliary agent solution is used, the concentration of the aqueous hydrate cage-forming auxiliary agent solution should be the same as the ratio of the hydrate cage-forming auxiliary agent to the total of the water forming the hydrate cage and the hydrate-forming auxiliary agent. good.

As a specific method for encapsulating water or the aqueous solution in the porous hollow particles, a conventional method can be used. For example, after the porous hollow particles are immersed in water or the aqueous solution, water or the aqueous solution is introduced into the porous hollow particles by reducing pressure, stirring, ultrasonic irradiation, shaking, or a combination of two or more of these operations. can be easily enclosed.
After encapsulating water or the aqueous solution into the porous hollow particles, the porous hollow particles may be separated from excess water or the aqueous solution by filtration, centrifugation, or the like.

2. Hydrate cage formation step In this step, the perforated hollow particles in which the water or the aqueous solution of the hydrate-forming aid is encapsulated, which is obtained in the water or aqueous solution encapsulation step, are cooled to allow the inside of the perforated hollow particles to A hydrate cage is formed from water or an aqueous hydrate-forming aid.

Without a hydrate-forming aid, considerable low temperature and high pressure conditions are required. Specifically, for example, under 1 atm of hydrogen, the temperature must be lowered to about -100°C or lower, and at about -70°C, the hydrogen pressure must be increased to several hundred atmospheres. On the other hand, when a hydrate-forming aid is used, the hydrate-forming aid is included in the hydrate cage to stabilize the hydrate cage. A hydrate cage can be formed at Specific conditions for forming a hydrate cage when using a hydrate formation aid depend on the type and amount of the hydrate formation aid used, and may be determined as appropriate. , -10°C or higher and 35°C or lower. More specifically, tetrahydrofuran may be cooled to about -10°C or higher and 33°C or lower, and tetrabutylammonium bromide may be cooled to about -10°C or higher and 35°C or lower.

Formation of hydrate cages can be confirmed, for example, by temperature change of perforated hollow particles. Specifically, when measuring the temperature of the perforated hollow particles encapsulating water or an aqueous solution of a hydrate cage-forming adjuvant while cooling the perforated hollow particles, a temperature peak is observed due to the formation of hydrate cages. The perforated hollow particles encapsulating water or the aqueous solution of the hydrate cage-forming adjuvant may be cooled until such a temperature peak is observed. If it is difficult to directly measure the temperature of the perforated hollow particles, a thermometer may be inserted between the perforated hollow particles to measure the temperature in the vicinity of the perforated hollow particles.

3. Hydrogen Occlusion Step In this step, a hydrogen carrier is produced by bringing hydrogen into contact with the hydrate cage formed in the hydrate cage forming step, thereby causing hydrogen to be occluded in the hydrate cage. In the present invention, since the hydrate cage is formed in the perforated hollow particles, hydrogen can be absorbed into the hydrate cage at relatively high temperature and relatively low pressure.

Specifically, in this step, hydrogen gas is circulated between the perforated hollow particles enclosing the hydrate cage, and the hydrogen is diffused inside through the pores of the perforated hollow particles to bring the hydrogen into contact with the hydrate cage. , hydrogen is stored in the hydrate cage. At this time, in order to stabilize the hydrate cage, it is preferable to keep the perforated hollow particles at a low temperature and also cool the hydrogen gas to a low temperature. The perforated hollow particles and the hydrogen gas are preferably adjusted within ±5° C. of the hydrate cage forming temperature. More specifically, the porous hollow particles and the hydrogen gas are preferably cooled to −10° C. or higher and 10° C. or lower, more preferably 5° C. or lower, and even more preferably 0° C. or lower. preferable.

Conventionally, low-temperature and high-pressure conditions were generally required for the production of hydrogen hydrate, but in the present invention, the use of perforated hollow particles allows hydrogen to be supplied to the hydrate cage at a temperature relatively close to room temperature as described above. It can be occluded, and the pressure of hydrogen at that time may be normal pressure or substantially normal pressure. However, the hydrogen gas may be pressurized to such an extent that hydrogen can flow between the perforated hollow particles without any problem. When pressurized, it is also expected that the mode of hydrogen absorption will be a double mode in which two hydrogen atoms enter the hydrate cage instead of a single mode in which one hydrogen atom enters. Specifically, the pressure of hydrogen gas may be adjusted to normal pressure or more and less than 1000 kPa. The pressure is preferably 500 kPa or less, more preferably 200 kPa or less, and even more preferably 150 kPa or less or 120 kPa or less. In addition, the upper limit of the pressure of hydrogen here is the absolute pressure.

In order to cause the hydrate cage to occlude hydrogen, for example, the perforated hollow particles enclosing the hydrate cage may be cooled and brought into contact with hydrogen. As described above, when the perforated hollow particles in which water or the aqueous solution of the hydrate cage-forming adjuvant is enclosed are cooled and the amount of heat absorbed is measured, a temperature peak is observed due to the formation of the hydrate cage. By bringing hydrogen into contact, hydrogen can be occluded in the hydrate cage.

The step of forming the hydrate cage and the step of absorbing hydrogen may be performed simultaneously. That is, the perforated hollow particles may be cooled while blowing cooled hydrogen gas into the perforated hollow particles in which water or the aqueous solution of the hydrate-forming auxiliary agent is enclosed. At this time, when the temperature of the perforated hollow particles is measured, an endothermic peak is observed during the formation of hydrate cages as the perforated hollow particles are cooled. Therefore, by bringing hydrogen into contact with the particles while cooling is continued thereafter, the hydrogen is occluded in the hydrate cages in the porous hollow particles, and hydrogen hydrate is formed.

INDUSTRIAL APPLICABILITY The hydrogen carrier according to the present invention can stably contain hydrogen at a relatively low temperature, and therefore can be used as a medium for transporting hydrogen. That is, it becomes possible to transport hydrogen by transporting the hydrogen carrier of the present invention. The temperature of the hydrogen carrier during transportation is preferably -10°C or higher and 10°C or lower, more preferably 5°C or lower, and even more preferably 0°C or lower. Although the lower limit of the temperature is not particularly limited, for example, -20°C or higher is preferable, and -15°C or higher or -10°C or higher is more preferable.

As noted above, the hydrogen carriers of the present invention can be produced at relatively high temperatures and at relatively low concentrations. Hydrogen hydrates also readily release hydrogen by slightly increasing the temperature or pressure from equilibrium conditions. Therefore, the hydrogen carrier according to the present invention is very useful especially as a hydrogen terminal carrier, since hydrogen can be easily released by heating to 15° C. or higher at normal pressure. The temperature during hydrogen release is preferably 20° C. or higher, more preferably 25° C. or higher. Although the upper limit of the temperature is not particularly limited, it can be 50° C. or less, for example.

This application claims the benefit of priority based on Japanese Patent Application No. 2017-165783 filed on August 30, 2017. The entire contents of the specification of Japanese Patent Application No. 2017-165783 filed on August 30, 2017 are incorporated herein by reference.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited by the following examples, and can be modified appropriately within the scope that can conform to the gist of the above and later descriptions. It is of course possible to implement them, and all of them are included in the technical scope of the present invention.

Example 1: Production of Hydrogen Carrier (1) Production of Perforated Hollow Particles 10 g of sodium polymethacrylate (molecular weight: 9500) was added to 30 g of a 30% by mass sodium silicate (Na ₂ SiO ₃ ) aqueous solution, and then pure water was added. to adjust the total volume to 36 mL. The resulting aqueous solution is hereinafter referred to as "aqueous phase-1". Separately, 0.5 g of surfactant polyoxyethylene (20) sorbitan monooleate (trade name: Tween80) and 0.25 g of sorbitan monooleate (trade name: Span80) were added to 72 mL of n-hexane. , and the above aqueous phase-1, and stirred at 8000 rpm for 1 minute using a homogenizer (“KHM-510S” manufactured by Kyoto Electronics Industry Co., Ltd.) to obtain a W/O emulsion. The resulting W/O emulsion was added to 500 mL of a 2M ammonium hydrogencarbonate aqueous solution (aqueous phase-2) and reacted at 35° C. and 400 rpm for 10 minutes to prepare a W/O/W emulsion. However, as the reaction progressed, the oil layer hardened and the emulsion state was dissolved. The obtained particles were separated by filtration, dried at 100° C. for 12 hours, and calcined at 500° C. for 5 hours to prepare hollow particles having nano-sized pores.
FIG. 1 shows an enlarged SEM photograph of the produced hollow particles with pores. Analysis of the obtained magnified photograph and the like revealed that the particle diameter was 18.29 μm, the outer shell thickness was 2.27 μm, the ratio of the total pore area to the surface area was 3.2%, and the average pore diameter was 0.34 μm. there were.

(2) Production of hydrogen carrier The obtained porous hollow particles were added to a 10% by mass aqueous solution of tetra-n-butylammonium bromide (TBAB), degassed under reduced pressure of 100 hPa for 30 minutes, and the 10% by mass aqueous solution of TBAB was removed. Encapsulated in hollow particles. Particles were separated by suction filtration. Using the apparatus shown in FIG. 2, hydrogen was occluded while cooling the TBAB aqueous solution in the obtained particles to form a hydrate cage. Specifically, 1.0 g of the above particles was placed in a 10 mL capacity container, and cooled with ice water while blowing normal pressure hydrogen gas cooled to −2° C. at 10 mL/min. After 40 minutes, the ice water was replaced with ice-cold brine adjusted to −5° C. and continued cooling to produce a hydrogen hydrate. FIG. 3 shows the cooling curve measured with a thermometer inserted between the particles. According to Fig. 3, a hydrate cage was formed about 7 minutes after the start of cooling at -5°C, and then the temperature stabilized at about -5°C, suggesting that hydrogen was occluded.

(3) Calculation of Hydrogen Storage Amount The hydrogen carrier was transferred to another cell, sealed, and allowed to stand at room temperature (25° C.) for 1 hour to melt the hydrogen hydrate. After that, 500 μL of the gas in the cell was sampled and the hydrogen concentration in the gas sample was measured by gas chromatography, and 0.644 vol % of the gas sample was hydrogen gas. In addition, since the void volume of the cell in which hydrogen hydrate was melted was 2 mL, the volume of hydrogen gas present in the cell was calculated as 2 x 0.644/100 = 0.0129 mL, and the mass was , [1×0.0129/(0.0821×298)]×2=0.00105 g. Here, since the total mass of the TBAB aqueous solution contained in the perforated hollow particles is 0.174 g, the mass ratio of hydrogen gas in TBAB/hydrogen hydrate is 0.00105/0.174×100=0.60. It was calculated as % by mass.

Claims (6)

Hollow silica particles or hollow zeolite particles and hydrogen hydrate,
The silica particles or hollow zeolite particles have a diameter of 3 μm or more and 1000 μm or less,
The outer shell of the hollow particle has pores with an equivalent circle diameter of 10 nm or more and 500 μm or less ,
A hydrogen carrier, wherein the hydrogen hydrate is contained in the hollow particles. 2. The hydrogen carrier according to claim 1, wherein the ratio of the total open area of the pores to the surface area of the hollow particles is 0.5% or more and 10% or less. 3. The hydrogen carrier according to claim 1 or 2 , wherein the hydrogen hydrate contains a hydrate-forming aid in addition to water and hydrogen. A method for manufacturing a hydrogen carrier, comprising:
A step of encapsulating water or an aqueous solution of a hydrate-forming auxiliary inside hollow silica particles or hollow zeolite particles whose outer shells have pores;
a step of cooling the hollow silica particles or hollow zeolite particles enclosing the water or the aqueous hydrate-forming aid solution to form a hydrate cage;
A step of causing hydrogen to be occluded in the hydrate cage by contacting the hydrate cage with hydrogen ;
The silica particles or hollow zeolite particles have a diameter of 3 μm or more and 1000 μm or less,
A method in which the outer shell of the hollow particles has pores with an equivalent circle diameter of 10 nm or more and 500 μm or less . 5. The method according to claim 4 , wherein the hydrogen pressure is normal pressure or more and less than 1000 kPa. A step of producing a hydrogen carrier by the method of claim 4 or 5 , and
A method for transporting hydrogen, comprising the step of transporting the hydrogen carrier.

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