KR20130037649A - Film electrode-bond and organic hydride manufacturing apparatus - Google Patents

Abstract

PURPOSE: A membrane electrode assembly and an organic hydride manufacturing apparatus are provided to obtain high energy efficiency even when manufacturing organic hydride through a single process using a single apparatus. CONSTITUTION: A membrane electrode assembly and an organic hydride manufacturing apparatus comprises an MEA(Membrane Electrode Assembly) arranged between a gas diffusion layer and a separator with grooves serving as a flow path. The MEA is formed by respectively attaching an anode catalyst layer and a cathode catalyst layer to both sides of a solid polymer electrolyte membrane. The cathode catalyst layer comprises catalyst metal(24) for making a hydride target into hydride; and a carrier(25) having a functional group(27) on the surface for reducing wettability to the hydride target. [Reference numerals] (AA) Good rapid diffusion property of organic hydride; (BB) Good diffusion property of a hydride target;

Description

TECHNICAL FIELD [0001] The present invention relates to a membrane electrode assembly and an organic hydride production apparatus,

The present invention relates to a membrane electrode assembly and an apparatus for producing an organic hydride for electrochemically producing an organic hydride.

While global warming due to carbon dioxide becomes serious, hydrogen is attracting attention as an energy source to take charge of the next generation instead of fossil fuels. Hydrogen fuel has only a small environmental burden because it discharges only water during fuel consumption and does not discharge carbon dioxide. On the other hand, since hydrogen is a gas at room temperature and normal pressure, a transportation, storage, and supply system has become a big problem.

Recently, an organic hydride system using hydrocarbons such as cyclohexane, methylcyclohexane, and decalin has attracted attention as a hydrogen storage method having excellent safety, transportability and storage ability. Since these hydrocarbons are liquid at room temperature, they are excellent in transportability. For example, toluene and methylcyclohexane are cyclic hydrocarbons having the same carbon number, while toluene is a saturated hydrocarbon having no double bond, whereas the hydrocarbon is an unsaturated hydrocarbon in which the bond between the hydrocarbons is a double bond. Methylcyclohexane is obtained by hydrogen addition reaction of toluene, and toluene is obtained by dehydrogenation reaction of methylcyclohexane. That is, by using the hydrogen addition reaction and the dehydrogenation reaction of these hydrocarbons, it becomes possible to store and supply hydrogen.

In order to prepare an organic hydride such as methylcyclohexane, it is first necessary to prepare hydrogen and react the hydrogen and toluene on the catalyst. That is, the developing step is a two-step process in which hydrogen is generated in a water electrolytic apparatus or the like, and hydrogen is reacted with toluene in a hydrogen addition reaction apparatus to produce an organic hydride.

Therefore, a plurality of apparatuses are required until the production of the organic hydride, which causes a problem of complication of the apparatus. In addition, since hydrogen is produced in the form of gaseous hydrogen until the hydrogen addition reaction, problems arise in terms of storage and transportation. If the hydrogen production apparatus and the hydrogen addition reaction apparatus are constructed adjacent to each other, the above problem is solved, but there is a problem of construction and operation cost, and the overall energy efficiency is lowered. In addition, since it is necessary to increase the size of the apparatus, there is a problem that the installation site is limited.

In contrast to the two-step process, a technique for producing an organic hydride in one step using a single device has been proposed (for example, Patent Document 1 and Non-Patent Document 1). These are electrochemically producing organic hydrides. For example, in Patent Document 1, a metal catalyst is disposed on both sides of a hydrogen-ion-permeable electrolyte membrane selectively permeable to hydrogen ions, water or water vapor is supplied to one side and supply gas is supplied to the other side, Hydrogen ions produced by electrolysis of water or water vapor are caused to undergo a hydrogen addition reaction with a hydrogenation product on the cathode side to produce an organic hydride. The reaction schemes of the anode and the cathode in the case of using toluene as the hydrogenated product are as follows.

[Reaction Scheme 1]

[Reaction Scheme 2]

Japanese Patent Application Laid-Open No. 2003-45449

Catalysis Today, 56, 307 (2000)

However, with these organic hydride production methods, it has been difficult to obtain high energy efficiency.

An object of the present invention is to provide a membrane electrode assembly and an apparatus for producing an organic hydride which can obtain high energy efficiency even when an organic hydride is produced in a single step using a single apparatus.

As one embodiment for achieving the above object, there is provided a membrane-electrode assembly in which a cathode catalyst layer for reducing aromatic hydrocarbons, which are to-be-purchased, and an anode catalyst layer for oxidizing water are disposed so as to sandwich a solid polymer electrolyte membrane having a proton conductivity, A catalyst metal which reacts with the hydride to react with the hydride, a carrier carrying the catalyst metal, and a proton-conductive solid polymer electrolyte, wherein a functional group which weakens the wettability to the subject matter hydrate is added to the surface of the carrier Wherein the membrane electrode assembly is a membrane electrode assembly.

The present invention also provides an apparatus for producing an organic hydride, characterized by comprising the membrane electrode assembly, a member for supplying the gas-containing substance to the cathode catalyst layer, and a member for supplying water or steam to the anode catalyst layer.

Further, it is also possible to use an organic hydrocarbon having a cathode catalyst layer, an anode catalyst layer, a separator for extracting organic hydride by supplying an aromatic hydrocarbon, which is a gas hydride, to the cathode catalyst layer, and supplying H ₂ O to the anode catalyst layer to discharge oxygen and water Wherein the anode catalyst layer is disposed on the other surface of the solid polymer electrolyte membrane and the cathode catalyst layer is formed by reducing the hydrogenated hydride to form a hydride And a carrier on which the catalytic metal is supported, wherein the carrier has a functional group which weakens the wettability to the subject matter hydrate on the surface thereof.

According to the present invention, by introducing a functional group that weakens the wettability to the subject matter hydrate on the surface of the carrier carrying the catalytic metal, even when the organic hydride is produced in one step using a single apparatus, Electrode assembly and an apparatus for producing an organic hydride can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing an example of an apparatus for producing an organic hydride according to an embodiment of the present invention; Fig.
Fig. 2 is a diagram showing a membrane electrode assembly according to an embodiment of the present invention. Fig. 2 (a) is a plan view, Fig. 2 (b) is a DE sectional view of a plan view, and Fig.
Fig. 3 is a diagram showing a prior art membrane electrode assembly, in which (a) is a plan view, (b) is a DE sectional view of a plan view, and Fig.
4 is a diagram showing an example of a relationship between a current density and an applied voltage in the organic hydride producing apparatus according to the first embodiment of the present invention.
5 is a diagram showing an example of a relationship between an addition ratio and an applied voltage in the organic hydride production apparatus according to the first embodiment of the present invention.
6 is a diagram showing an example of the relationship between the current density and the applied voltage in the organic hydride producing apparatus according to Comparative Example 1. Fig.
7 is a diagram showing an example of the relationship between the addition rate and the applied voltage in the organic hydride production apparatus according to Comparative Example 1. [Fig.
8 is a diagram showing an example of the current density and the addition rate in the organic hydride production apparatus according to the first to third embodiments and the comparative example 1 of the present invention.

The present inventors have studied the reason why high energy efficiency can not be obtained when the organic hydride is prepared in a single step using a single conventional apparatus. As a result, it has been found that, as one of the reasons, there is a problem in the wettability of an object to be treated such as toluene to an electrode. An electrode of a single device for producing an organic hydride in one step is composed of a layer in which a proton conductive electrolyte and a catalyst are mixed, and is called a catalyst layer. Among them, the catalyst is formed by supporting a metal catalyst such as platinum on a carrier. The carrier is required to have a high specific surface area in order to increase the dispersibility by preventing aggregation of a metal catalyst such as platinum, which has high electron conductivity, and a carbon-based material is usually used.

Incidentally, the wettability of the subject matter such as toluene with respect to the carbon-based material is very strong, and is easily wetted. For example, although activated carbon is a carbon-based material having a large specific surface area, it is known that toluene adsorbs to activated carbon. When the wettability of the object to be treated such as toluene with respect to the carbon of the carrier is strong, it is assumed that the object to be adsorbed covers the surface of the carrier of the carrier and adsorbs or stays on the surface of the carrier to inhibit the continuous supply of the carrier. In this case, a catalyst which does not contribute to the reaction and is not supplied with the subject gas is generated, resulting in low energy efficiency. Therefore, it has been found that the surface of the carrier carbon is modified to weaken the wettability of the object-to-be-treated such as toluene, thereby preventing the object-to-be-received on the surface of the catalyst layer from being stably supplied.

The present invention relates to a membrane electrode assembly or an organic hydride device for electrochemically producing an organic hydride, which is produced on the basis of the above-mentioned knowledge, and is characterized in that a surface modification is carried out as a catalyst carrier to convert functional groups such as a sulfonic acid group, hydroxyl group and carboxyl group , And carbon having weakened wettability with respect to the object to be treated such as toluene can be used. Further, the catalyst layer in which the catalyst carrying the metal catalyst on the carbon and the proton conductive solid polymer electrolyte are appropriately mixed with each other has an electrode structure formed on the front and back surfaces of the proton-conductive solid polymer electrolyte membrane. In this electrode, water or water vapor is supplied to the anode side, and a voltage is applied between the anode and cathode in the state where the cathode side is supplied with a mercury gas, whereby the electrolysis of water in the anode, the hydrogen An addition reaction can be carried out to generate an organic hydride.

Embodiments according to the present invention will be described in detail with reference to the drawings.

Fig. 1 shows an example of an apparatus for producing an organic hydride according to an embodiment of the present invention. The apparatus for producing an organic hydride of the present embodiment is characterized in that an anode catalyst layer 13 is bonded to one surface of a solid polymer electrolyte membrane 12 and a cathode catalyst layer 14 is bonded to the other surface of the solid polymer electrolyte membrane 12, is configured across: (MEA M embrane E lectrode ssembly a) a gas diffusion layer 15, a separator 11, a groove is formed as a flow path of gas or the like. A gasket 16 for a gas seal is inserted between the pair of separators 11.

The separator 11 is preferably made of a material such as a carbon plate formed of a dense graphite plate, a carbon material such as graphite or carbon black, or a metal material having excellent corrosion resistance such as stainless steel or titanium. It is also preferable that the surface of the separator 11 is plated with a noble metal or a conductive coating excellent in corrosion resistance and heat resistance is applied to the surface of the separator 11. On the surface of the separator 11 facing the anode catalyst layer 13 and the cathode catalyst layer 14, a groove serving as a reaction gas or liquid flow path is formed. Water or water vapor is supplied to the flow channel of the separator 11 on the anode side. Water or water vapor flowing in the flow channel is supplied to the anode catalyst layer 13 through the gas diffusion layer 15. Further, the gasifier to be treated is supplied to the separator 11 on the cathode side. The gas hydrate flowing in the flow channel is supplied to the cathode catalyst layer 14 through the gas diffusion layer 15. As the supply method of the subject matter hydrate, a liquid-like subject matter hydrate may be supplied as it is, or a vapor-like object to be vaporized using He gas, N ₂ gas or the like as a carrier may be supplied.

The gas diffusion layer 15 is provided to uniformly supply the reactive material (gas or liquid) supplied to the flow path of the separator 11 into the surface of the catalyst layer and is provided with a gas permeable substrate such as carbon paper or carbon cloth use.

The gasket 16 may be made of any material that is insulating, particularly resistant to hydrogen or anhydride, or organic hydride, and has low permeability and airtightness. Examples of the gasket 16 include butyl rubber, Viton rubber, EPDM rubber -Propylene-diene rubber), and the like.

When water or water vapor is supplied to the anode side and toluene is supplied to the cathode side, and a voltage is applied between the anode and cathode, the electrolysis reaction of water in the reaction formula 1 occurs in the anode. The proton produced by the electrolysis reaction of the reaction scheme 1 moves to the cathode catalyst layer 14 through the solid polymer electrolyte membrane 12 and the hydrogen addition reaction of the reaction formula 2 occurs in the cathode catalyst layer, and methylcyclohexane .

[Reaction Scheme 1]

[Reaction Scheme 2]

In the organic hydride apparatus of the present embodiment, the hydrogen addition reaction is carried out with respect to the hydrocarbons electrochemically by the above reaction to produce the organic hydride.

Fig. 2 shows an electrode portion of the organic hydride production apparatus of this embodiment. 2 (a), 2 (b) and 2 (c) are a plan view and a plan view of the MEA in which the cathode catalyst layer 22 and the anode catalyst layer 23 are formed on the front and rear sides of the solid polymer electrolyte membrane 21, Sectional view of a portion DE of FIG.

As shown in the cross section of the MEA, the cathode and the anode are formed as a dense catalyst layer above and below the solid polymer electrolyte membrane 21. As shown in the enlarged view of the cathode catalyst layer 22, the catalyst metal 24 is supported on the carbon 25 as the catalyst carrier. The carbon 25 is subjected to a surface treatment, and a functional group 27 is introduced. As a result, the subject matter such as toluene is hardly wetted with the catalyst, and the surface of the catalyst layer is covered with the object-to-be-treated so that the object-to-be-treated is stably supplied to the catalyst. In addition, the organic hydride produced by the hydrogen addition reaction is also highly acidic. In addition, reference numeral 28 denotes a hydride or an organic hydride.

The carbon 25 is adhered to each other by the solid polymer electrolyte 26. The catalytic metal 24 has a network structure connected to each other through the carbon 25 and forms an electron passage necessary for the reaction of the reaction formula (2). The solid polymer electrolyte 26 in the catalyst layer also has a connected network structure and forms a path for the proton necessary for the reaction of the reaction formula (2).

The electrode reaction is performed at a three-phase interface at which the catalytic metal 24 on the carbon 25 contacts the solid polymer electrolyte and the hydrate, which is a reactant. Since the protons of the proton are formed by the solid polymer electrolyte 26 in the electrode of the present embodiment, the three-phase interface is also formed in the catalyst metal 24 not in direct contact with the solid polymer electrolyte membrane 21, The metal catalyst has a structure capable of contributing to the electrode reaction. It is preferable that the solid polymer electrolyte includes a solid polymer electrolyte membrane 21 and that the cathode catalyst layer includes a solid polymer electrolyte 26 in order to increase the energy.

Fig. 3 shows an electrode portion of a prior art organic hydride manufacturing apparatus. 3 (a), 3 (b) and 3 (c) are a plan view and a plan view of the MEA in which the cathode catalyst layer 32 and the anode catalyst layer 33 are formed on the front and rear sides of the solid polymer electrolyte membrane 31, Sectional view of a portion DE of FIG. In the electrode shown in Fig. 3, there is a problem that the subject matter to be adsorbed or retained on the carbon surface is covered with the subject matter of the carrier so that the supply of the subject matter to the catalyst is interrupted. As a result, a catalyst which does not contribute to the reaction and is not supplied with the subject gas is generated, resulting in low energy efficiency. Reference numeral 34 denotes a catalyst metal, 35 denotes a carbon carrier, and 36 denotes a hydride or an organic hydride.

The carbon support 25 of the present embodiment is characterized in that the functional group 27 is introduced by surface modification. As a result, the subject matter hydrate is less likely to be wetted, the retention of the subject matter-present on the surface of the cathode catalyst layer 22 is prevented, and the supply of the subject matter hydrate to the cathode catalyst layer 22 is not hindered.

The functional group 27 introduced into the carbon surface may be any as long as it lowers the wettability with the object to be treated such as toluene to improve the oil repellency. Examples thereof include a sulfonic acid group, a phosphonic acid group, a hydroxyl group, a sulfomethyl group, a carboxyl group, a carbonyl group, and a carboxylic acid group. Of these, at least one of them may be contained, but a sulfonic acid group is particularly preferable for practical use.

As the carrier 25, any electron conductive carbon may be used. Examples thereof include furnace black, channel black, acetylene black, amorphous black, carbon nanotubes, carbon nanohorns, carbon black, activated carbon and graphite. These may be used singly or in combination.

As a method for introducing a functional group through surface treatment of carbon, for example, when a sulfonic acid group is introduced, a sulfonic acid group can be introduced by treatment with sulfuric acid gas, fuming sulfuric acid, sulfuric acid or the like. In addition, a sulfomethyl group can be introduced by treatment with sodium sulfite, sodium bisulfate, an aqueous formalin solution, paraformaldehyde or the like. It is also conceivable that oxygen is irradiated to carbon for the introduction of the hydroxyl group.

On the other hand, the catalytic metal 24 used in the present embodiment may be formed of a catalytic material having a hydrogen addition action, for example, Ni, Pd, Pt, Rh, Ir, Re, Ru, Mo, W, (Pt), ruthenium (Ru), rhodium (Rh), palladium (Pa), iridium (Ir), molybdenum (Mo), rhenium Re), tungsten (W), and alloys thereof are practically preferable. The hydrogen addition catalyst is preferably made into fine particles in order to reduce the cost by reducing the catalyst metal and to increase the reaction surface area.

As the method of carrying the catalyst metal 24 on the carrier 25 of the carrier, there is no particular limitation such as a coprecipitation method, a thermal decomposition method, and an electroless plating method.

The MEA of the present embodiment can be manufactured by the following method. First, a cathode catalyst paste in which a catalyst in which a catalytic metal 24 is supported on a surface-modified carbon 25, a solvent in which a solid polymer electrolyte and a solid polymer electrolyte are dissolved is added and thoroughly mixed, and a platinum black, a solid polymer electrolyte and a solid polymer A solvent for dissolving an electrolyte is added to prepare an anode catalyst paste sufficiently mixed. These pastes are respectively sprayed on a release film such as a polyfluoroethylene (PTFE) film by a spray drying method or the like, followed by drying at 80 DEG C to evaporate the solvent to form a cathode and an anode catalyst layer. Next, the cathode and the anode catalyst layer are bonded to each other by a hot press method with the solid polymer electrolyte membrane 21 sandwiched therebetween, and the peeling film (PTFE) is peeled off, whereby the MEA of this embodiment can be manufactured.

As another example of the production of the MEA of the present embodiment, a catalyst in which the catalyst metal 24 is supported on the surface-modified carbon 25, a solvent for dissolving the solid polymer electrolyte and the solid polymer electrolyte, It is also possible to spray an anode catalyst paste directly mixed with a catalyst paste, a solvent for dissolving platinum black, a solid polymer electrolyte and a solid polymer electrolyte, directly onto the solid polymer electrolyte membrane 21 by a spray drying method or the like .

Examples of the organic polymer constituting the solid polymer electrolyte membrane 21 include perfluorocarbonsulfonic acid, polystyrene, polyetherketone, polyetheretherketone, polysulfone, polyether sulfone, and other engineering plastic materials, A proton donor such as a sulfonic acid group, a sulfonic acid group, a sulfonic acid group, a sulfonic acid group, a sulfonic acid group, a phosphoric acid group or a carboxyl group. In addition, in the above material, the material stability can be improved by forming a crosslinked structure or partially fluorinating it.

As the solid polymer electrolyte contained in the catalyst layer, a polymer material exhibiting proton conductivity can be used. For example, a fluorine-based or fluorine-based sulfonated or alkylenesulfonated polymer typified by a perfluorocarbon sulfonic acid resin or a polyperfluorostyrene sulfonic acid resin Polymers and polystyrenes. In addition to these, materials obtained by introducing a proton donor such as a polysulfone, a polyether sulfone, a polyether ether sulfone, a polyether ether ketone, or a hydrocarbon polymer into a sulfonic acid group. A composite electrolyte of the organic polymer and metal oxide hydrate of the present embodiment may also be used.

An aromatic hydrocarbon may be used as the object to be treated, and examples thereof include benzene, toluene, xylene, mesitylene, naphthalene, methylnaphthalene, anthracene, biphenyl, phenanthroline, . Hydrogen is added to the double bonds of these carbon atoms, so that hydrogen can be stored.

Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited to the following examples.

Example 1

As the catalyst, a catalyst in which 30 wt% of Pt fine particles were dispersed and supported on carbon black was used. First, 100 g of this catalyst was preheated at 105 DEG C for 1 hour. Thereafter, the sulfur trioxide gas heated to 100 ° C was introduced at a concentration of 12 vol.% With respect to the dry air and reacted. The reaction time was 2 hours. Thereafter, the solution was cooled, the catalyst was poured into ion-exchange water, stirred and filtered, and washed with ion-exchanged water until the pH of the filtrate became constant.

The resulting catalyst, a peak was observed at a ^{bar, 620㎝ -1, 1037㎝ -1, 1225㎝} -1 measure the infrared absorption spectrum. This was considered to be a peak based on a sulfonic acid group -SO ₃ H, and it was confirmed that a sulfonic acid group was introduced on the surface of the carbon black of the support. The equivalent of the introduced sulfonic acid group was 1.8 milliequivalents / g of dried carbon carrier.

The catalyst thus obtained was used as a cathode catalyst to prepare an MEA having the structure shown in Fig. Nafion (manufactured by DuPont) was used as the electrolyte membrane. The cathode catalyst layer 22 was formed by directly applying a catalyst slurry to Nafion using a spray coater. The cathode catalyst layer 22 was applied to Nafion in the following order.

First, Nafion was placed on a hot plate of the substrate and fixed by suction. The temperature of the hot plate was set at 50 캜. Next, a mask was formed thereon, and a cathode catalyst slurry was applied by a spray coater (manufactured by Nodoson Co., Ltd.). As the cathode catalyst slurry, the catalyst prepared in this example and water, 5 wt% Natrium solution, and 221 solution (1-propanol: 2-propanol: water = 2: 2: 1) were mixed in a ratio of 2: 1.2: 5.4: By weight. The coating conditions were liquid pressure of 0.01 MPa, swath pressure of 0.15 MPa, atomization pressure of 0.15 MPa, dry-substrate distance of 60 mm, and substrate temperature of 50 캜. The amount of the cathode catalyst was 0.4 mgPt-cm <" ^{2 &} gt ;.

After the cathode catalyst layer 22 was formed on the Nafion surface, the anode catalyst layer 23 was formed on the back surface. The anode catalyst layer 23 was formed by a transfer method. First, an anode catalyst slurry was prepared. Platinum black HiSPEC 1000 (manufactured by Johnson Matte), 5 wt% Nafion solution and 221 solution were mixed as the anode catalyst slurry at a weight ratio of 1: 1.11: 2.22. It was applied by an applicator onto a Teflon (registered trademark) sheet. An anode catalyst layer applied on a Teflon (registered trademark) sheet was formed on the surface of a Nafion by a hot press (SA-401-M manufactured by Tester Industry Co., Ltd.). The hot press pressure was 37.2 kgf · cm ^-2 , the hot press temperature was 120 ° C., and the hot press time was 2 minutes. The amount of the anode catalyst was 4.8 mgPt-cm <" ^{2 &} gt ;.

The prepared MEA was assembled into the organic hydride producing apparatus shown in Fig. Toluene was used for the digestible material. Toluene was supplied to the cathode at a rate of 10 cc / min, and a voltage was applied between the anode and the cathode in a state where pure water was supplied at 5 cc / min to the anode. The cell temperature was 80 캜. 4 shows the current value with respect to the applied voltage. When the voltage was 1.6 V or more, the current flowed and the reaction proceeded. As the voltage increased to 2.2V, the current increased and the reaction proceeded. When the cathode exhaust gas was analyzed by gas chromatography, toluene and methylcyclohexane were detected. As a result, it was confirmed that methyl cyclohexane was produced by hydrogen addition reaction of toluene. Fig. 5 shows the conversion ratio of toluene to methylcyclohexane calculated from the peak intensity of gas chromatography. The higher the voltage, the better the conversion rate. The maximum value under this condition was 55% when 2.2 V was applied.

As described above, according to the present embodiment, by introducing a functional group that weakens the wettability to the carrier to be treated on the carrier surface of the catalyst, even when the organic hydride is produced in one step using a single apparatus, A membrane electrode assembly and an organic hydride producing apparatus which can obtain the membrane electrode assembly and the organic hydride producing apparatus.

(Comparative Example 1)

As the catalyst, a catalyst in which 30 wt% of Pt fine particles were dispersed and supported on carbon black not subjected to a surface treatment for introducing a functional group was used. This catalyst was used as a cathode catalyst to prepare an MEA. The manufacturing method and conditions were the same as in Example 1. [

The prepared MEA was assembled into the organic hydride producing apparatus shown in Fig. 1, and the hydrogen addition reaction test with toluene was carried out under the same conditions as in Example 1. Fig. 6 shows the current value with respect to the applied voltage. The current value was smaller than that in Example 1. This is presumably because the wettability of toluene with respect to carbon was strong, so that toluene stays on the surface of carbon, and the supply of toluene to the catalyst was interrupted. Further, the gas flow rate was measured using a gas flow meter. As a result, the gas flow rate was increased in Comparative Example 1 as compared with Example 1. This is presumably because, in a catalyst to which toluene is not supplied, hydrogen generation is caused by the reaction of the following reaction formula 3, not the hydrogen addition reaction of toluene.

Scheme 3

Figure 7 shows the conversion of toluene to methylcyclohexane. The maximum value under this condition was 30% when 2.2 V was applied. Which was lower than Example 1. This is considered to be because not only a hydrogen addition reaction but also hydrogen generation occur simultaneously in Comparative Example 1. The energy efficiency of the organic hydride formation becomes lower.

As described above, it is impossible to obtain a membrane electrode assembly or an apparatus for producing an organic hydride having a high energy efficiency even in the structure similar to the embodiment except for the introduction of a functional group.

[Example 2]

As the catalyst, a catalyst in which 30 wt% of Pt fine particles were dispersed and supported on carbon black was used. 10 g of this catalyst and 15 g of anhydrous aluminum chloride (AlCl ₃ ) were mixed, and thiophosphoryl chloride (PSCl ₃ ) was gradually added. The temperature was kept constant at 35 캜, and 54 ml was slowly added. Thereafter, it was maintained at 75 캜 for 45 minutes. After cooling, 50 ml of chloroform was added and the mixture was filtered. After sufficiently washing with diethyl ether, 200 ml of ion-exchanged water was added and the mixture was refluxed for 20 hours. The infrared absorption spectrum of the obtained catalyst was measured, and a peak was observed at 1000 to 1120 cm ^-1 and 840 to 910 cm ^-1 . This was considered to be a peak based on phosphonic acid, and it was confirmed that a phosphonic acid group was introduced on the surface of the carbon black of the support. The equivalent amount of the phosphonic acid group introduced was 1.8 milliequivalents / g dry carbon carrier.

The prepared catalyst was used as a cathode catalyst to prepare an MEA. The manufacturing method and conditions were the same as in Example 1. [

The prepared MEA was assembled into the organic hydride producing apparatus shown in Fig. 1, and the hydrogen addition reaction test with toluene was carried out under the same conditions as in Example 1. The results are shown in FIG. 8 is a current density and a conversion rate when 2.2 V is applied between the anode and the cathode. The current density and the conversion rate were both increased as compared with Comparative Example 1 in which the surface of the carrier was not treated with carbon, and the effect of introducing the phosphonic acid group on the surface of the carbon was recognized.

As described above, according to the present embodiment, by introducing a functional group that weakens the wettability to the carrier to be treated on the carrier surface of the catalyst, even when the organic hydride is produced in one step using a single apparatus, A membrane electrode assembly and an organic hydride producing apparatus which can obtain the membrane electrode assembly and the organic hydride producing apparatus.

[Example 3]

As the catalyst, a catalyst in which 30 wt% of Pt fine particles were dispersed and supported on carbon black was used. This catalyst was subjected to oxygen plasma irradiation. The apparatus used for the irradiation was a PDC210 plasma apparatus model number manufactured by Yamato Garas Co., the pressure before introducing oxygen in the chamber was 0.1 Torr or less, and the pressure after introducing oxygen was 0.5 Torr. The output of the high-frequency power source of the apparatus was 100 W, and the plasma irradiation time was 150 seconds. The infrared absorption spectrum of the obtained catalyst was measured, and a broad peak at 3000 to 3600 cm ^-1 was observed. This was considered to be a peak based on hydroxyl group -OH, and it was confirmed that a hydroxyl group was introduced on the surface of the Pt-carrying carbon black.

The prepared catalyst was used as a cathode catalyst to prepare an MEA. The manufacturing method and conditions were the same as in Example 1. [

The prepared MEA was assembled into the organic hydride producing apparatus shown in Fig. 1, and the hydrogen addition reaction test with toluene was carried out under the same conditions as in Example 1. The results are shown in FIG. The current density and the conversion rate were both increased as compared with Comparative Example 1 in which the surface treatment of the carbon in the carrier was not carried out. As a result, the effect of introducing a hydroxyl group onto the carbon surface was recognized.

As described above, according to the present embodiment, by introducing a functional group that weakens the wettability to the carrier to be treated on the carrier surface of the catalyst, even when the organic hydride is produced in one step using a single apparatus, A membrane electrode assembly and an organic hydride producing apparatus which can obtain the membrane electrode assembly and the organic hydride producing apparatus.

In addition, this invention is not limited to an Example mentioned above, A various modified example is included. For example, the above-described embodiments are described in detail in order to facilitate understanding of the present invention and are not limited to those having all the configurations described above. It is also possible to replace some of the configurations of the embodiments with those of the other embodiments, and the configurations of the other embodiments can be added to the configurations of any of the embodiments. In addition, it is possible to add, delete, or replace other configurations to a part of the configurations of each embodiment.

11: Separator
12: Solid polymer electrolyte membrane
13: anode catalyst layer
14: cathode catalyst layer
15: gas diffusion layer
16: Gasket
21: Solid polymer electrolyte membrane
22: cathode catalyst layer
23: anode catalyst layer
24: catalyst metal
25: Carbon carrier
26: Solid polymer electrolyte
27: Functional group
28: a hydrate or an organic hydride
31: Solid polymer electrolyte membrane
32: cathode catalyst layer
33: anode catalyst layer
34: catalyst metal
35: Carbon carrier
36: a hydrate or an organic hydride

Claims (14)

There is provided a membrane electrode assembly arranged so that a cathode catalyst layer for reducing an aromatic hydrocarbon, which is a subject gas hydrate, and an anode catalyst layer for oxidizing water are disposed so as to sandwich a proton-conductive solid polymer electrolyte membrane therebetween,
Wherein the cathode catalyst layer comprises a catalytic metal that reduces the adsorbed material to react with the hydride, a carrier carrying the catalytic metal, and a proton-conductive solid polymer electrolyte,
A membrane electrode assembly, wherein a functional group for weakening the wettability to the hydride is introduced on the surface of the carrier. An apparatus for producing an organic hydride, comprising: the membrane electrode assembly according to claim 1; a member for supplying the subject gasoline to the cathode catalyst layer; and a member for supplying water or water vapor to the anode catalyst layer. The method of claim 1,
Wherein the functional group comprises at least one of a sulfonic acid group, a phosphonic acid group, a hydroxyl group, a sulfomethyl group, a carboxyl group, a carbonyl group, and a carboxylic acid group. The method of claim 1,
Wherein the catalytic metal is made of platinum, ruthenium, rhodium, palladium, iridium, molybdenum, rhenium, tungsten and an alloy containing at least a part of them. The method of claim 1,
Characterized in that the object-to-be-handled is benzene, toluene, xylene, mesitylene, naphthalene, methylnaphthalene, or anthracene. The method of claim 2,
Wherein the object hydride is benzene, toluene, xylene, mesitylene, naphthalene, methylnaphthalene, or anthracene. An organic hydride production method comprising the steps of supplying a cathode catalyst layer, an anode catalyst layer, an aromatic hydrocarbon as a gas hydride to the cathode catalyst layer to extract an organic hydride, and supplying H ₂ O to the anode catalyst layer to discharge oxygen and water As an apparatus,
Wherein the cathode catalyst layer is disposed on one surface of the solid polymer electrolyte membrane, the anode catalyst layer is disposed on the other surface of the solid polymer electrolyte membrane,
Wherein the cathode catalyst layer comprises a catalyst metal for reducing the to-be-burned hydride to react with the hydride, and a carrier carrying the catalyst metal,
The carrier is an organic hydride production apparatus, characterized in that the surface has a functional group that weakens the wettability to the hydride. The method of claim 7, wherein
Wherein hydrogen is supplied from the anode catalyst layer to the cathode catalyst layer. The method of claim 7, wherein
Wherein the carrier is an electron conductive carbon. The method of claim 7, wherein
Wherein the functional group is a sulfonic acid group. The method of claim 7, wherein
Wherein the separator has conductivity and has flow grooves through which the subject matter hydrate or H ₂ O flows. The method of claim 7, wherein
Wherein supply of the subject matter hydrate to the cathode catalyst layer and supply of H ₂ O to the anode catalyst layer are carried out through a diffusion layer. The method of claim 12,
Wherein the diffusion layer is carbon paper or carbon cloth. The method of claim 7, wherein
Wherein the cathode catalyst layer comprises a solid polymer electrolyte.

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