A direct fuel cell system based on organic liquid hydrogen transfer

Abstract

The present application provides a direct fuel cell system based on organic liquid hydrogen transfer, which relates to the technical field of hydrogen energy power generation. The system includes a storage tank, organic liquid A, organic liquid B, a hydrogen transfer reactor, a direct fuel cell, a gas-liquid separator, a premixing tank, a first heat exchanger, a second heat exchanger, a first buffer tank and a second buffer tank. The hydrogen transfer reactor is used to transfer the combined hydrogen of the hydrogen-rich organic liquid A to the hydrogen-poor organic liquid B, and the direct fuel cell is used to directly convert the combined hydrogen of the hydrogen-rich organic liquid B into electric energy. The present application adopts a hydrogen transfer reactor and a direct fuel cell, with organic liquid B as an intermediate medium, to achieve high-efficiency conversion of hydrogen storage in organic liquid A into electric energy, avoiding the high energy consumption of dehydrogenation of hydrogen-rich organic liquids, reducing the input of external energy, and having the advantages of small dehydrogenation energy consumption and high energy efficiency.

Description

Technical Field

[0001] This application relates to the technical field of hydrogen energy power generation, and particularly to a direct fuel cell system based on organic liquid hydrogen transfer. Background Art

[0002] Hydrogen energy has the advantages of high calorific value, clean and pollution-free, simple energy conversion process, rich sources, etc., and is known as the "ultimate energy" in the 21st century. However, the problems of hydrogen energy storage and transportation are still the key bottlenecks restricting its large-scale application and commercial promotion. High-pressure gaseous hydrogen storage needs to be stored under a high pressure of 35 Mpa - 70 Mpa, increasing the risks of leakage and explosion, and having low safety. Cryogenic liquid hydrogen storage requires consuming a large amount of energy to liquefy hydrogen and store it at an extremely low temperature (about -253°C), with high costs, high energy consumption, easy volatilization, high requirements for equipment, and complex auxiliary systems. Organic liquid hydrogen storage is considered an ideal hydrogen storage method because of its high hydrogen storage density, high safety, being in a liquid phase at normal temperature and pressure, convenient transportation, being compatible with existing oil transportation facilities, and low storage and transportation costs.

[0003] In the application of organic liquid hydrogen storage, organic liquids that can carry multiple hydrogen atoms are used as hydrogen carriers, with a relatively high hydrogen storage density. However, such hydrogen carriers need to release hydrogen through a catalytic dehydrogenation reaction under external heating conditions, and then supply the released high-purity hydrogen to a hydrogen fuel cell for power generation. However, since the dehydrogenation reaction of such organic liquids is a strongly endothermic reaction, the dehydrogenation process requires maintaining a high temperature and continuous heat supply. The heat consumption for dehydrogenation reaches 20% - 30% of the total energy of the organic liquid for storing hydrogen, with high dehydrogenation energy consumption, resulting in a reduced overall energy utilization efficiency of the system.

[0004] Therefore, the direct organic liquid fuel cell power generation technology has emerged. This technology directly converts the chemical energy of the fuel into electrical energy through an electrochemical reaction of an organic liquid fuel with a small hydrogen storage density in a direct organic liquid fuel cell without the need for dehydrogenation. The organic liquids usually used in direct organic liquid fuel cells are organic liquids that can carry two or a small number of hydrogen atoms, with high energy conversion efficiency, but their hydrogen storage density is small. Although organic liquids that can carry multiple hydrogen atoms have advantages in hydrogen storage density, they are currently not suitable for directly generating electricity in direct organic liquid fuel cells and can only be used in hydrogen fuel cells after dehydrogenation. Therefore, the existing fuel cell systems cannot simultaneously meet the high-performance power generation requirements of low dehydrogenation energy consumption, high energy efficiency, and large hydrogen storage density. Summary of the Invention

[0005] Aiming at the above problems, the present invention provides a direct fuel cell system based on organic liquid hydrogen transfer, which realizes efficient hydrogen transfer between organic liquids with different hydrogen storage densities, so as to simultaneously meet the advantages of low dehydrogenation energy consumption, high energy efficiency, and large hydrogen storage density.

[0006] To achieve this object, the present invention provides a direct fuel cell system based on organic liquid hydrogen transfer, and the technical solution adopted is as follows:

[0007] A direct fuel cell system based on organic liquid hydrogen transfer, the system comprising:

[0008] An organic liquid A module, including a hydrogen storage part for storing and transporting organic liquid A; the organic liquid A includes hydrogen-rich organic liquid A and hydrogen-poor organic liquid A;

[0009] An organic liquid B module, including a direct fuel cell and organic liquid B; the organic liquid B includes hydrogen-rich organic liquid B and hydrogen-poor organic liquid B; wherein, the direct fuel cell is used to receive and utilize the hydrogen-rich organic liquid B to generate electricity directly, generating hydrogen-poor organic liquid B;

[0010] Wherein, the hydrogen storage density of the organic liquid A is greater than that of the organic liquid B;

[0011] A hydrogen transfer reactor, including a dehydrogenation reaction chamber and a hydrogenation reaction chamber;

[0012] The dehydrogenation reaction chamber is communicated with the hydrogen storage part, and is used to receive the hydrogen-rich organic liquid A transported from the hydrogen storage part, perform dehydrogenation reaction to generate hydrogen-poor organic liquid A and hydrogen, and jointly transport them to the hydrogen storage part;

[0013] The hydrogenation reaction chamber is communicated with the direct fuel cell and is also communicated with the hydrogen storage part, and is used to receive the hydrogen-poor organic liquid B after the direct fuel cell generates electricity and the hydrogen output from the hydrogen storage part, perform hydrogenation reaction to generate hydrogen-rich organic liquid B, so that the hydrogen in the organic liquid A is transferred to the organic liquid B;

[0014] Wherein, the dehydrogenation reaction chamber and the hydrogenation reaction chamber are in contact with each other, so that the heat generated by the hydrogenation reaction in the hydrogenation reaction chamber is transferred to the dehydrogenation reaction chamber to supply heat for the dehydrogenation reaction.

[0015] As one of the preferred solutions, the dehydrogenation reaction chamber is sleeved on the outer periphery of the hydrogenation reaction chamber, and porous media are respectively filled in the dehydrogenation reaction chamber and the hydrogenation reaction chamber, and the porous media are used for loading catalysts and strengthening mass transfer and heat transfer.

[0016] As one of the preferred solutions, the hydrogen transfer reactor further includes a heating jacket sleeved on the outer periphery of the dehydrogenation reaction chamber;

[0017] Wherein, the heating jacket is electrically connected to the direct fuel cell to compensate for the heat required for the dehydrogenation reaction in the dehydrogenation reaction chamber under demand working conditions.

[0018] As one of the preferred solutions, when the reaction temperature and heat release of adding 1 mole of hydrogen to the hydrogen-deficient organic liquid B are both greater than the reaction temperature and heat absorption of removing 1 mole of hydrogen from the hydrogen-rich organic liquid A, the direct fuel cell stops heating the heating jacket;

[0019] In the cold start condition of the hydrogen transfer reactor, or when the reaction temperature or heat release of adding 1 mole of hydrogen to the hydrogen-deficient organic liquid B is less than the reaction temperature or heat absorption of removing 1 mole of hydrogen from the hydrogen-rich organic liquid A, the direct fuel cell starts to electrically heat the heating jacket to compensate for the heat required for the dehydrogenation reaction.

[0020] As one of the preferred solutions, the hydrogen-carrying part includes:

[0021] A storage tank, including an independent hydrogen-rich organic liquid A storage chamber and a hydrogen-deficient organic liquid A storage chamber. The hydrogen-rich organic liquid A storage chamber stores the hydrogen-rich organic liquid A, and the hydrogen-deficient organic liquid A storage chamber stores the hydrogen-deficient organic liquid A;

[0022] A heat exchanger group, including a first heat exchanger and / or a second heat exchanger; wherein,

[0023] The first heat exchanger is respectively connected to the hydrogen-rich organic liquid A storage chamber and the dehydrogenation reaction chamber, and is used to recover the waste heat of the dehydrogenation reaction product to preheat the hydrogen-rich organic liquid A; and / or, the second heat exchanger is respectively connected to the hydrogen-rich organic liquid A storage chamber and the hydrogenation reaction chamber, and is used to recover the waste heat of the hydrogenation reaction product to preheat the hydrogen-rich organic liquid A; wherein, the second heat exchanger is also connected to the dehydrogenation reaction chamber, and is used to input the preheated hydrogen-rich organic liquid A into the dehydrogenation reaction chamber;

[0024] A gas-liquid separator is respectively connected to the first heat exchanger, the hydrogen-deficient organic liquid A storage chamber and the hydrogenation reaction chamber, or respectively connected to the hydrogen-deficient organic liquid A storage chamber and the hydrogenation reaction chamber, and is used to receive and separate the dehydrogenation reaction product, return the hydrogen-deficient organic liquid A to the hydrogen-deficient organic liquid A storage chamber, and at the same time transport the hydrogen to the hydrogenation reaction chamber.

[0025] As one of the preferred solutions, the heat exchanger group includes a first heat exchanger and a second heat exchanger, and the first heat exchanger and the second heat exchanger are connected to use the first heat exchanger to perform primary preheating on the hydrogen-rich organic liquid A, and at the same time use the second heat exchanger to perform secondary preheating on the hydrogen-rich organic liquid A after primary preheating.

[0026] As one of the preferred solutions, the organic liquid A module further includes:

[0027] The first buffer tank, which is connected to the gas-liquid separator and is used for receiving the hydrogen gas;

[0028] The premixing tank, which is respectively connected to the first buffer tank, the direct fuel cell and the hydrogenation reaction chamber, and is used for mixing the hydrogen gas and the hydrogen-deficient organic liquid B, and conveying the mixture obtained by mixing to the hydrogenation reaction chamber.

[0029] As one of the preferred solutions, the organic liquid B module further includes:

[0030] The second buffer tank, which is respectively connected to the direct fuel cell and the second heat exchanger, and is used for receiving the hydrogen-rich organic liquid B output by the second heat exchanger and conveying it into the direct fuel cell.

[0031] As one of the preferred solutions, the porous medium includes any one of foam metal, metal fiber sintered material and ceramic foam; and / or, the catalyst loaded in the hydrogenation reaction chamber includes any one of platinum, ruthenium and palladium; the catalyst loaded in the dehydrogenation reaction chamber includes any one of platinum, palladium and rhodium.

[0032] As one of the preferred solutions, the direct fuel cell is an organic liquid B fuel cell, which is used for directly taking the hydrogen-rich organic liquid B as the anode reactant, and taking air or oxygen as the cathode reactant at the same time.

[0033] As one of the preferred solutions, the organic liquid A includes one or a mixture of several of toluene, biphenyl, naphthalene, ethylcarbazole, N-ethylcarbazole, dibenzyltoluene, indole, quinoline, phenazine, 2-methylquinoline and N-methylindole; and / or, the organic liquid B includes at least one of saturated ketone and methanol.

[0034] Compared with the prior art, the present application has the following advantages:

[0035] The system provided by the embodiment of the present application conducts the dehydrogenation reaction and the hydrogenation reaction of two organic liquids with different hydrogen storage densities in independent reaction chambers, without relying on specific molecular structure matching or hydrogenation / dehydrogenation site matching. Therefore, this system can be widely applicable to various combinations of hydrogen storage liquid A and hydrogen storage liquid B, and has significant advantages such as strong universality, simple engineering implementation and high energy efficiency.

[0036] The system provided by the embodiment of the present invention has the advantages of large hydrogen storage density, high safety, being in a liquid phase at normal temperature and pressure, and high compatibility with the existing liquid fuel infrastructure for the organic liquid hydrogen storage technology. By combining a hydrogen transfer reactor and a direct fuel cell, with organic liquid B as an intermediate medium, it realizes the high-efficiency conversion of the hydrogen stored in organic liquid A into electrical energy. At the same time, the heat coupling during the transfer process avoids the high energy consumption of the dehydrogenation of organic liquids, reduces the input of external energy, and has the advantages of small dehydrogenation energy consumption and high energy efficiency. Brief Description of the Drawings

[0037] To more clearly illustrate the technical solutions of this application, the drawings required for the description of this application will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0038] Figure 1 is the system framework diagram of a direct fuel cell system based on organic liquid hydrogen transfer provided by an embodiment of this application;

[0039] Figure 2 is the structural diagram of a hydrogen transfer reactor provided by an embodiment of this application;

[0040] Figure 3 is the side view of a hydrogen transfer reactor provided by an embodiment of this application.

[0041] Description of the Reference Numerals:

[0042] 1. Storage tank; 2. Lean hydrogen organic liquid A storage chamber; 3. Rich hydrogen organic liquid A storage chamber; 4. First heat exchanger; 5. Second heat exchanger; 6. Hydrogen transfer reactor; 7. Gas-liquid separator; 8. First buffer tank; 9. Second buffer tank; 10. Premixing tank; 11. Direct fuel cell; 12. External; 13. Heating jacket; 14. Dehydrogenation reaction chamber; 15. Hydrogenation reaction chamber; 141. First porous medium; 151. Second porous medium. Detailed Embodiments

[0043] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the drawings in the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of this application without creative efforts fall within the protection scope of this application.

[0044] It can be known that the direct fuel cell 11 using organic liquid B that can carry two or a small number of hydrogen atoms has a high technology maturity. However, the direct organic liquid fuel cell technology using organic liquid A with a high hydrogen storage density that can carry multiple hydrogen atoms is not yet mature. The main reasons are as follows: The molecular structure of organic liquid A with a high hydrogen storage capacity is complex, with many hydrogen atoms. It is difficult to activate these molecules on the catalyst surface, the reaction rate is extremely low, and the electrochemical path becomes complex, with multiple intermediate products. It is difficult to control the selectivity, and by-products are prone to poisoning or carbon deposition on the catalyst surface. Therefore, organic liquid A is usually not used for power generation in the direct fuel cell 11, but is used as a hydrogen storage and transportation carrier, and then dehydrogenated to supply a mature hydrogen fuel cell system.

[0045] In the related art, it has been proposed that perhydrodibenzyltoluene and acetone are directly mixed to undergo a chemical reaction to generate dibenzyltoluene and isopropanol, and then isopropanol is introduced into a direct isopropanol fuel cell for power generation, avoiding the high energy consumption problem of organic liquid dehydrogenation. This method stores hydrogen between two chemical reactants (such as organic fuel A and organic fuel B) that can undergo a direct reaction, and transfers hydrogen to another chemical reactant through a direct chemical reaction to achieve energy release. However, this method is restricted by the constraints of chemical reaction conditions, has extremely high raw material selectivity and pairing dependence. If the target fuel (such as a certain organic fuel A or a certain organic fuel B) itself does not participate in the chemical reaction, it cannot be used as the terminal fuel. Therefore, the transfer efficiency and path are not flexible enough, and the types of fuels available for selection are extremely limited. In addition, after the two chemical reactants complete the reaction at one time, the components generated by the reaction are difficult to effectively separate and recycle.

[0046] More critically, in the continuous flow reaction of directly mixing perhydrodibenzyltoluene and acetone, the yield of isopropanol generated by the chemical reaction is only 13.6%, and there are many side reaction products, which are difficult to meet the actual application requirements.

[0047] In view of this, the present invention aims to solve the high energy consumption problem of organic liquid dehydrogenation, and at the same time achieve high hydrogen storage density and high energy efficiency. It proposes an independent reaction of two organic liquids with different hydrogen storage densities, and realizes the cross-border integration and synergistic effect between a high hydrogen storage liquid (organic fuel A) and a directly power-generable liquid (organic fuel B) through hydrogen tandem-thermal coupling of hydrogenation and dehydrogenation reactions.

[0048] Refer to Figure 1 as shown Figure 1 is the overall structural composition diagram of the direct fuel cell system based on organic liquid hydrogen transfer shown in the present invention. As Figure 1 shown, the present invention provides a direct fuel cell system based on organic liquid hydrogen transfer. The system includes: an organic liquid A module, including a hydrogen-carrying part for storing and transporting organic liquid A; organic liquid A includes hydrogen-rich organic liquid A and hydrogen-poor organic liquid A; an organic liquid B module, including a direct fuel cell 11 and organic liquid B; organic liquid B includes hydrogen-rich organic liquid B and hydrogen-poor organic liquid B; wherein, the direct fuel cell 11 is used to receive and directly generate electricity using hydrogen-rich organic liquid B to generate hydrogen-poor organic liquid B; wherein, the hydrogen storage density of organic liquid A is greater than that of organic liquid B.

[0049] The hydrogen transfer reactor 6 includes a dehydrogenation reaction chamber 14 and a hydrogenation reaction chamber 15; the dehydrogenation reaction chamber 14 is communicated with the hydrogen carrier section, and is used to receive the hydrogen-rich organic liquid A transported from the hydrogen carrier section, carry out dehydrogenation reaction to generate the hydrogen-poor organic liquid A and hydrogen gas, and jointly transport them to the hydrogen carrier section; the hydrogenation reaction chamber 15 is communicated with the direct fuel cell 11 and is also communicated with the hydrogen carrier section, and is used to receive the hydrogen-poor organic liquid B after the direct fuel cell 11 generates electricity and the hydrogen gas output from the hydrogen carrier section, carry out hydrogenation reaction to generate the hydrogen-rich organic liquid B, so that the hydrogen in the organic liquid A is transferred to the organic liquid B; wherein, the dehydrogenation reaction chamber 14 and the hydrogenation reaction chamber 15 are in contact with each other, so that the heat generated by the hydrogenation reaction in the hydrogenation reaction chamber 15 is transferred into the dehydrogenation reaction chamber 14 to supply heat for the dehydrogenation reaction.

[0050] Specifically, this system is mainly composed of three parts: hydrogen storage and transportation of the organic liquid A module, hydrogen transfer between the organic liquid A and the organic liquid B, and hydrogen utilization of the organic liquid B on the direct fuel cell 11. The hydrogen carrier section provides storage and transportation with the organic liquid A as the hydrogen storage and transportation carrier. The organic liquid A can be a liquid organic hydrogen carrier carrying multiple hydrogen atoms, with a high hydrogen storage density and can be used for large-capacity hydrogen storage. The organic liquid A is divided into a hydrogen-rich state and a hydrogen-poor state. The hydrogen-rich organic liquid A in the hydrogen-rich state can release a large amount of hydrogen gas through dehydrogenation reaction to achieve efficient hydrogen storage and release, and at the same time is converted into the hydrogen-poor organic liquid A in the hydrogen-poor state for recycling in the organic liquid A module. The organic liquid B module includes the organic liquid B and the direct fuel cell 11. The organic liquid B can be a liquid organic hydrogen carrier carrying two or a small number of hydrogen atoms. Therefore, the hydrogen-rich organic liquid B can directly carry out an electrocatalytic reaction in the direct fuel cell 11, with high energy efficiency, and at the same time is converted into the hydrogen-poor organic liquid B for recycling in the organic liquid B module.

[0051] Preferably, the organic liquid A includes one or a mixture of several of toluene, biphenyl, naphthalene, ethylcarbazole, N-ethylcarbazole, dibenzyltoluene, indole, quinoline, phenazine, 2-methylquinoline, and N-methylindole. For example, N-ethylcarbazole / dodecahydro-N-ethylcarbazole, carbazole / dodecahydrocarbazole, indole / octahydroindole, N-methylindole / octahydro-N-methylindole, 2-methylquinoline / decalin-2-methylquinoline, phenazine / tetradecahydrophenazine, etc. The organic liquid B includes at least one of saturated ketone and methanol.

[0052] The hydrogen transfer reactor 6 includes two reaction chambers with independent structures but heat-coupled. The dehydrogenation reaction chamber 14 is communicated with the hydrogen carrier section, so it can receive the hydrogen-rich organic liquid A, carry out dehydrogenation reaction to release hydrogen gas and generate the hydrogen-poor organic liquid A, and the mixture of hydrogen gas and the hydrogen-poor organic liquid A then flows out of the dehydrogenation reaction chamber 14 and flows to the hydrogen carrier section.

[0053] The hydrogenation reaction chamber 15 is connected or indirectly connected to the dehydrogenation reaction chamber 14 through a hydrogen carrier section. Therefore, the hydrogen in the mixture of hydrogen and hydrogen-deficient organic liquid A flowing in the hydrogen carrier section can directly enter the hydrogenation reaction chamber 15 and mix with the organic liquid B in the hydrogenation reaction chamber 15, or the hydrogen first mixes with the organic liquid B, and then the mixture of hydrogen and organic liquid B enters the hydrogenation reaction chamber 15 together. In this embodiment, the hydrogen can be separated from the mixture of hydrogen and hydrogen-deficient organic liquid A by a gas-liquid separator 7, and the hydrogen-deficient organic liquid A is recycled.

[0054] The hydrogenation reaction chamber 15 is respectively connected to the anode inlet and anode outlet of the direct fuel cell 11. Therefore, it can receive the hydrogen-deficient organic liquid B discharged from the anode outlet in the direct fuel cell 11, mix with the hydrogen generated by the dehydrogenation reaction in the dehydrogenation reaction chamber 14, carry out a hydrogenation reaction to be reconverted into a hydrogen-rich organic liquid B, and then flow from the hydrogenation reaction chamber 15 to the anode inlet in the direct fuel cell 11.

[0055] Therefore, in this embodiment, the independent hydrogenation reaction and dehydrogenation reaction are respectively carried out through the hydrogenation reaction chamber 15 and the dehydrogenation reaction chamber 14. The hydrogen is transferred from the hydrogen-rich organic liquid A with a high hydrogen storage density to the hydrogen-deficient organic liquid B with a low hydrogen storage density through the hydrogen transfer reactor 6, and then the combined hydrogen of the hydrogen-rich organic liquid B is directly converted into electric energy through the direct fuel cell 11. The organic liquid B acts as an intermediate medium in the system, realizing the combination of the organic liquid A with a large hydrogen storage capacity and the organic liquid B fuel cell with advanced direct fuel cell technology. The organic liquid B converts the hydrogen energy from the organic liquid A into an energy carrier that can be utilized by the direct fuel cell 11, realizing efficient transfer hydrogenation, taking into account both the system energy utilization rate and the high hydrogen storage density.

[0056] Since the dehydrogenation reaction and hydrogenation reaction of the two organic liquids with different hydrogen storage densities are carried out in independent reaction chambers and do not rely on specific molecular structure matching or hydrogenation / dehydrogenation site matching, this system can be widely applied to various combinations of hydrogen storage liquid A and hydrogen storage liquid B. For example, the organic liquid A and organic liquid B can be flexibly selected according to different requirements, and it has significant advantages such as strong universality, simple engineering implementation, and high energy efficiency.

[0057] Another remarkable progress of this embodiment is that the reactions in the dehydrogenation reaction chamber 14 and the hydrogenation reaction chamber 15 are independent but heat-coupled. The dehydrogenation reaction chamber 14 and the hydrogenation reaction chamber 15 are arranged in contact. The dehydrogenation reaction in the dehydrogenation reaction chamber 14 requires heat absorption, while the hydrogenation reaction in the hydrogenation reaction chamber 15 requires heat release. Therefore, the internal energy cycle utilization of the reaction heat is realized, that is, the heat released during the hydrogenation process is transferred to the heat absorption during the dehydrogenation process, greatly reducing the dehydrogenation energy consumption, significantly improving the overall energy efficiency of the system, and reducing the external heat source demand.

[0058] In this embodiment, the dehydrogenation reaction chamber 14 and the hydrogenation reaction chamber 15 are two independent reaction chambers. Therefore, there are more choices for their sizes, shapes, and positions. Preferably, the hydrogen transfer reactor 6 can be a concentric tube-in-tube reactor, that is, the dehydrogenation reaction chamber 14 and the hydrogenation reaction chamber 15 are sleeved with each other, and the two form a full-circumference wrapping to form a large-area wall heat transfer. In some embodiments, the dehydrogenation reaction chamber 14 and the hydrogenation reaction chamber 15 can also be arranged in a stacked manner. One side wall of the two is closely attached to achieve wall heat transfer, and at the same time, a heat-conducting material is arranged between the dehydrogenation reaction chamber 14 and the hydrogenation reaction chamber 15.

[0059] Thus, the organic liquid hydrogen storage technology adopted in the embodiment of the present invention has the advantages of large hydrogen storage density, high safety, being in a liquid phase at normal temperature and pressure, and high compatibility with the infrastructure of existing liquid fuels. By combining the hydrogen transfer reactor 6 and the direct fuel cell 11, with organic liquid B as an intermediate medium, the high-efficiency conversion of storing hydrogen in organic liquid A to electrical energy is realized. At the same time, the heat coupling during the transfer process avoids the high energy consumption of organic liquid dehydrogenation, reduces the input of external energy, and has the advantages of small dehydrogenation energy consumption and high energy efficiency.

[0060] The present invention adopts a transfer hydrogenation - direct fuel cell sequence: first, transfer hydrogen from organic liquid A with a large hydrogen storage density to organic liquid B, and then directly electrocatalytically oxidize and generate electricity using the hydrogen-rich organic liquid B as a raw material. Its energy efficiency exceeds 50%, which is much greater than the traditional dehydrogenation - fuel cell sequence (35%).

[0061] Preferably, as Figure 2 and Figure 3 shown, Figure 2 shows the structural diagram of the hydrogen transfer reactor of the present invention; Figure 3 shows the side view of the hydrogen transfer reactor of the present invention. The dehydrogenation reaction chamber 14 is sleeved on the outer periphery of the hydrogenation reaction chamber 15, and porous media are respectively filled in the dehydrogenation reaction chamber 14 and the hydrogenation reaction chamber 15. The porous media are used to load the catalyst and strengthen mass and heat transfer. In this embodiment, the dehydrogenation reaction chamber 14 is coated outside the hydrogenation reaction chamber 15, with a compact structure, a large wall contact area between the two, and a short heat conduction path. The heat released by the hydrogenation reaction is directly used to drive the dehydrogenation reaction, which can effectively reduce the dependence on external heat sources and form a highly integrated and low-energy-consuming coupled thermal management organic liquid fuel cell system.

[0062] The porous media filled in the two reaction chambers have a high specific surface area and strong thermal conductivity themselves, can firmly load the catalyst, and at the same time transfer the heat of the hydrogenation reaction chamber 15 to the entire dehydrogenation reaction chamber 14 efficiently and uniformly, providing the heat required for the dehydrogenation reaction.

[0063] In some embodiments, the first porous medium 141 filled in the dehydrogenation reaction chamber 14 and the second porous medium 151 filled in the hydrogenation reaction chamber 15 may be the same or different.

[0064] Preferably, the porous medium filled in the hydrogenation reaction chamber 15 and the dehydrogenation reaction chamber 14 is one of metal foam, sintered metal fiber material, and ceramic foam; the porosity of the porous medium is 70% - 98%; the catalyst for hydrogenation reaction is a noble metal catalyst such as platinum, ruthenium, palladium, etc., with a loading of 0.5 wt% - 5 wt%, and the reaction temperature is 150°C - 250°C. The catalyst for dehydrogenation reaction is a noble metal catalyst such as platinum, palladium, rhodium, etc., with a loading of 0.3 wt% - 5 wt%, and the reaction temperature is 150°C - 300°C.

[0065] Furthermore, the hydrogen transfer reactor 6 further includes a heating jacket 13 sleeved on the outer periphery of the dehydrogenation reaction chamber 14; wherein, the heating jacket 13 is electrically connected to the direct fuel cell 11 to compensate for the heat required for the dehydrogenation reaction in the dehydrogenation reaction chamber 14 under demand conditions. In this embodiment, the heating jacket 13 is connected to the direct fuel cell 11, and during the operation of the system, electrical energy is provided by the direct fuel cell 11 to supply energy to the heating jacket 13, which is used for preheating the hydrogen transfer reactor 6 during the cold start phase and for heat compensation when the temperature or heat of the hydrogenation reaction is insufficient to support the heat absorbed by the dehydrogenation reaction.

[0066] Wherein, the electric heating element in the heating jacket 13 is a resistance wire.

[0067] Specifically, when the reaction temperature and the heat released during the addition of one mole of hydrogen in the hydrogenation reaction of the hydrogen - poor organic liquid B are both greater than the reaction temperature and the heat absorbed during the removal of one mole of hydrogen in the dehydrogenation reaction of the hydrogen - rich organic liquid A, the direct fuel cell 11 stops supplying power to the heating jacket 13, and the heating jacket 13 does not need to work. When the reaction temperature or the heat released during the addition of one mole of hydrogen in the hydrogenation reaction of the hydrogen - poor organic liquid B is less than the reaction temperature or the heat absorbed during the removal of one mole of hydrogen in the dehydrogenation reaction of the hydrogen - rich organic liquid A, the heating jacket 13 operates using the electrical energy of the direct fuel cell 11 to supplement the lacking heat.

[0068] This embodiment is used to illustrate the hydrogen - carrying part, and the hydrogen - carrying part includes:

[0069] The storage tank 1 includes a hydrogen-rich organic liquid A storage chamber 3 and a hydrogen-lean organic liquid A storage chamber 2 that are independent of each other. The hydrogen-rich organic liquid A storage chamber 3 stores the hydrogen-rich organic liquid A, and the hydrogen-lean organic liquid A storage chamber 2 stores the hydrogen-lean organic liquid A; a heat exchanger group, including a first heat exchanger 4 and / or a second heat exchanger 5; wherein, the first heat exchanger 4 is respectively connected to the hydrogen-rich organic liquid A storage chamber 3 and the dehydrogenation reaction chamber 14, and is used to recover the waste heat of the dehydrogenation reaction product to preheat the hydrogen-rich organic liquid A; and / or, the second heat exchanger 5 is respectively connected to the hydrogen-rich organic liquid A storage chamber 3 and the hydrogenation reaction chamber 15, and is used to recover the waste heat of the hydrogenation reaction product to preheat the hydrogen-rich organic liquid A; wherein, the second heat exchanger 5 is also connected to the dehydrogenation reaction chamber 14, and is used to input the preheated hydrogen-rich organic liquid A into the dehydrogenation reaction chamber.

[0070] The gas-liquid separator 7 is respectively connected to the first heat exchanger 4, the hydrogen-lean organic liquid A storage chamber 2 and the hydrogenation reaction chamber 15, or is respectively connected to the hydrogen-lean organic liquid A storage chamber 2 and the hydrogenation reaction chamber 15, and is used to receive and separate the dehydrogenation reaction product, send the hydrogen-lean organic liquid A back to the hydrogen-lean organic liquid A storage chamber 2, and at the same time send the hydrogen to the hydrogenation reaction chamber 15.

[0071] In this embodiment, the storage tank 1 includes a hydrogen-rich organic liquid A storage chamber 3 and a hydrogen-lean organic liquid A storage chamber 2; the first heat exchanger 4 and / or the second heat exchanger 5 is one of a shell-and-tube heat exchanger, a double-pipe heat exchanger, a plate heat exchanger, and a heat pipe heat exchanger, and is respectively used to recover the waste heat of the dehydrogenation reaction product and / or the hydrogenation reaction product to perform single-stage preheating on the hydrogen-rich organic liquid A.

[0072] In a design form of this embodiment, when the first heat exchanger 4 is set alone, the first heat exchanger 4 is respectively connected to the dehydrogenation reaction chamber 14, the hydrogen-rich organic liquid A storage chamber 3 and the gas-liquid separator 7. Therefore, the waste heat of the dehydrogenation reaction product (a mixture of hydrogen and hydrogen-lean organic liquid A) in the dehydrogenation reaction chamber 14 heats the hydrogen-rich organic liquid A transported from the hydrogen-rich organic liquid A storage chamber 3, realizing single-stage preheating of the hydrogen-rich organic liquid A. At the same time, the heat-exchanged dehydrogenation reaction product is input into the gas-liquid separator 7 for separation of hydrogen and hydrogen-lean organic liquid A. The single-stage preheated hydrogen-rich organic liquid A then continues to flow into the dehydrogenation reaction chamber 14 through another outlet of the first heat exchanger 4 for dehydrogenation reaction. In this design form, the hydrogenation reaction chamber 15 is directly connected to the direct fuel cell 11. In this way, the waste heat of the dehydrogenation reaction product can be used alone to preheat the hydrogen-rich organic liquid A.

[0073] In another design form of this embodiment, when the second heat exchanger 5 is provided separately, the second heat exchanger 5 is respectively connected to the hydrogenation reaction chamber 15, the hydrogen-rich organic liquid A storage chamber 3, and the direct fuel cell 11, and is also connected to the dehydrogenation reaction chamber 14. Therefore, the waste heat of the hydrogenation reaction product (hydrogen-rich organic liquid B) in the hydrogenation reaction chamber 15 heats the hydrogen-rich organic liquid A transported from the hydrogen-rich organic liquid A storage chamber 3, realizing single-stage preheating of the hydrogen-rich organic liquid A. At the same time, the dehydrogenation reaction product after heat exchange is input into the direct fuel cell 11 for power generation. The single-stage preheated hydrogen-rich organic liquid A then continues to flow through the second heat exchanger 5 into the dehydrogenation reaction chamber 14 for dehydrogenation reaction. In this design form, the dehydrogenation reaction chamber 14 is directly connected to the gas-liquid separator 7. In this way, the waste heat of the hydrogenation reaction product can be used alone to preheat the hydrogen-rich organic liquid A.

[0074] In another design form of this embodiment, the first heat exchanger 4 and the second heat exchanger 5 can be provided simultaneously. The hydrogen-rich organic liquid A output from the hydrogen-rich organic liquid A storage chamber 3 is divided into two streams and introduced into the first heat exchanger 4 and the second heat exchanger 5. The hydrogen-rich organic liquid A is preheated separately by the first heat exchanger 4 and the second heat exchanger 5. In this way, the waste heat of the dehydrogenation reaction product and the hydrogenation reaction product is used alone and simultaneously to preheat the hydrogen-rich organic liquid A respectively.

[0075] Preferably, the first heat exchanger 4 and the second heat exchanger 5 are provided simultaneously, and the first heat exchanger 4 and the second heat exchanger 5 are interconnected. Two-stage preheating of the organic liquid B is achieved through the coupled multi-stage heat exchanger, and the two-stage preheated hydrogen-rich organic liquid B is transported to the direct fuel cell 11 through the second heat exchanger 5. In the specific implementation manner, the hydrogen-carrying part includes: a storage tank 1, including a hydrogen-rich organic liquid A storage chamber 3 and a hydrogen-deficient organic liquid A storage chamber 2 that are independent of each other. The hydrogen-rich organic liquid A storage chamber 3 stores the hydrogen-rich organic liquid A, and the hydrogen-deficient organic liquid A storage chamber 2 stores the hydrogen-deficient organic liquid A; the first heat exchanger 4, which is respectively connected to the hydrogen-rich organic liquid A storage chamber 3 and the dehydrogenation reaction chamber 14, and is used to recover the waste heat of the dehydrogenation reaction product to perform primary preheating on the hydrogen-rich organic liquid A; the gas-liquid separator 7, which is respectively connected to the first heat exchanger 4, the hydrogen-deficient organic liquid A storage chamber 2, and the hydrogenation reaction chamber 15, and is used to receive and separate the dehydrogenation reaction product, return the hydrogen-deficient organic liquid A to the hydrogen-deficient organic liquid A storage chamber 2, and at the same time transport the hydrogen to the hydrogenation reaction chamber 15; the second heat exchanger 5, which is respectively connected to the first heat exchanger 4 and the hydrogenation reaction chamber 15, and is used to recover the waste heat of the hydrogenation reaction product to perform secondary preheating on the hydrogen-rich organic liquid A after primary preheating; wherein, the second heat exchanger 5 is also connected to the dehydrogenation reaction chamber 14, and is used to input the hydrogen-rich organic liquid A after secondary preheating into the dehydrogenation reaction chamber 14.

[0076] Furthermore, the organic liquid A module further includes: a first buffer tank 8, connected to the gas-liquid separator 7 for receiving hydrogen; a premixing tank 10, connected to the first buffer tank 8, the direct fuel cell 11, and the hydrogenation reaction chamber 15 respectively, for mixing hydrogen and hydrogen-deficient organic liquid B and delivering the mixture of hydrogen and hydrogen-deficient organic liquid B to the hydrogenation reaction chamber 15. Even further, the organic liquid B module further includes: a second buffer tank 9, connected to the direct fuel cell 11 and the second heat exchanger 5 respectively, for receiving the hydrogen-rich organic liquid B output from the second heat exchanger 5 and delivering it to the direct fuel cell 11.

[0077] As a specific explanation of this embodiment, the outlet of the hydrogen-rich organic liquid A storage chamber 3 of the storage tank 1 is connected to the cold fluid inlet of the first heat exchanger 4, the cold fluid outlet of the first heat exchanger 4 is connected to the cold fluid inlet of the second heat exchanger 5, and the cold fluid outlet of the second heat exchanger 5 is connected to the inlet of the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6. The outlet of the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6 is connected to the hot fluid inlet of the first heat exchanger 4, and the hot fluid outlet of the first heat exchanger 4 is connected to the inlet of the gas-liquid separator 7. The outlet of the gas-liquid separator 7 is respectively connected to the inlet of the first buffer tank 8 and the inlet of the hydrogen-deficient organic liquid A storage chamber 2 of the storage tank 1. The outlet of the first buffer tank 8 is connected to the inlet of the premixing tank 10.

[0078] The outlet of the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6 is connected to the hot fluid inlet of the first heat exchanger 4, and the hot fluid outlet of the first heat exchanger 4 is connected to the inlet of the gas-liquid separator 7. The reaction product of the dehydrogenation reaction chamber 14 enters the gas-liquid separator 7 through the waste heat recovery of the first heat exchanger 4 and is separated into hydrogen and hydrogen-deficient organic liquid A. Hydrogen enters the premixing tank 10 through the first buffer tank 8, and the hydrogen-deficient organic liquid A enters the hydrogen-deficient organic liquid A storage chamber 2 of the storage tank 1 for storage, waiting for recycling.

[0079] The outlet of the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6 is connected to the hot fluid inlet of the second heat exchanger 5, the hot fluid outlet of the second heat exchanger 5 is connected to the inlet of the second buffer tank 9, the outlet of the second buffer tank 9 is connected to the inlet of the direct fuel cell 11, the outlet of the direct fuel cell 11 is connected to the inlet of the premixing tank 10, and the outlet of the premixing tank 10 is connected to the inlet of the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6.

[0080] The hydrogenation reaction product of the hydrogenation reaction chamber 15 is hydrogen-rich organic liquid B. The hydrogen-rich organic liquid B enters the second buffer tank 9 through the waste heat recovery of the second heat exchanger 5 for storage, and then enters the direct fuel cell 11 for reaction power generation. The reaction product of the direct fuel cell 11 is hydrogen-deficient organic liquid B. The hydrogen-deficient organic liquid B enters the premixing tank 10, mixes with hydrogen, and then enters the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6 to undergo a hydrogenation reaction to generate hydrogen-rich organic liquid B. In this way, continuous power generation is achieved through circulation.

[0081] In some other embodiments, the direct fuel cell 11 is a direct organic liquid B fuel cell, which is used to directly react and generate electricity with the hydrogen-rich organic liquid B as the anode reactant; the cathode reactant of the direct fuel cell 11 is air or oxygen; the direct fuel cell 11 is a type of proton exchange membrane fuel cell. In this embodiment, the direct fuel cell 11 is a proton exchange membrane fuel cell, and the hydrogen-rich organic liquid B is directly input into the anode, which can avoid the problems of reforming, storage and transportation of gaseous hydrogen in traditional fuel cells. At the same time, the organic liquid B includes multiple types. According to the specific fuel type of the pre-selected organic liquid B, a direct organic liquid B fuel cell that matches its chemical structure and reaction characteristics is preferably selected. Its anode structure and catalyst type have good synergy with a specific type of organic liquid B, and can achieve efficient power generation under the conditions of low polarization and high stability.

[0082] In summary, the working principle of the system provided by the present invention will be fully described below in conjunction with specific embodiments.

[0083] A direct fuel cell system based on organic liquid hydrogen transfer includes a storage tank 1, an organic liquid A, an organic liquid B, a hydrogen transfer reactor 6, a direct fuel cell 11, a gas-liquid separator 7, a premixing tank 10, a first heat exchanger 4, a second heat exchanger 5, a first buffer tank 8, and a second buffer tank 9. The storage tank 1 is used to store the hydrogen-rich organic liquid A and the hydrogen-depleted organic liquid A. The power generation method relying on this system includes:

[0084] S1. The hydrogen-rich organic liquid A flows out from the outlet of the hydrogen-rich organic liquid A storage chamber 3 of the storage tank 1 and enters the cold fluid inlet of the first heat exchanger 4. After heat exchange, it flows out from the cold fluid outlet of the first heat exchanger 4 and enters the cold fluid inlet of the second heat exchanger 5. After the second heat exchange, it flows out from the cold fluid outlet of the second heat exchanger 5, and at this time the preheating is completed;

[0085] S2. The preheated hydrogen-rich organic liquid A enters the inlet of the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6 and contacts the dehydrogenation catalyst in the dehydrogenation reaction chamber 14 to undergo a dehydrogenation reaction. The reaction is endothermic and the reaction temperature is 150°C - 300°C. After the reaction, a dehydrogenation reaction product, that is, a product mixture of hydrogen and the hydrogen-depleted organic liquid A, is generated;

[0086] S3. The product mixture flows out from the outlet of the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6 and enters the hot fluid inlet of the first heat exchanger 4. After waste heat recovery, it flows out from the hot fluid outlet of the first heat exchanger 4 and enters the inlet of the gas-liquid separator 7, where it is separated into hydrogen and the hydrogen-depleted organic liquid A. The hydrogen-depleted organic liquid A flows out from the liquid outlet of the gas-liquid separator 7 and enters the hydrogen-depleted organic liquid A storage chamber 2 of the storage tank 1, waiting for recycling; the hydrogen flows out from the gas outlet of the gas-liquid separator 7 and enters the inlet of the first buffer tank 8 for storage;

[0087] S4. Hydrogen flows out from the outlet of the first buffer tank 8 and enters the inlet of the premixing tank 10, mixes with the hydrogen-deficient organic liquid B from the direct fuel cell 11, flows out from the outlet of the premixing tank 10, is pressurized by a pump and then enters the inlet of the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6, contacts with the hydrogenation catalyst in the hydrogenation reaction chamber 15 to undergo a hydrogenation reaction. The reaction releases heat, and the heat is transferred to the dehydrogenation reaction chamber 14 through heat convection and heat conduction of the porous medium to supply heat for the dehydrogenation reaction. After the reaction, a hydrogen-rich organic liquid B is generated.

[0088] S5. The hydrogen-rich organic liquid B flows out from the outlet of the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6, enters the hot fluid inlet of the second heat exchanger 5, and after waste heat recovery, flows out from the hot fluid outlet of the second heat exchanger 5 and enters the inlet of the second buffer tank 9 for storage. Then it flows out from the outlet of the second buffer tank 9 and enters the direct fuel cell 11 to generate electricity through reaction. The reaction generates a hydrogen-deficient organic liquid B and electric energy. The electric energy is transmitted to the heating jacket 13 and the electricity-consuming unit in the outside 12. The hydrogen-deficient organic liquid B flows out from the outlet of the direct fuel cell 11 and enters the premixing tank 10. Thus, the cycle continues to generate electricity. The operating temperature of the direct fuel cell 11 is 60°C - 90°C.

[0089] Example 1:

[0090] N-ethylcarbazole is selected as the organic liquid A, acetone is selected as the organic liquid B, a direct isopropanol fuel cell is selected as the direct fuel cell 11, 5wt% Pd / Al2O3 is selected as the dehydrogenation catalyst, and 2wt% Pd / Al2O3 is selected as the hydrogenation catalyst. Since the dehydrogenation reaction temperature of perhydro-N-ethylcarbazole (160°C - 180°C) is lower than the hydrogenation reaction temperature of acetone (180°C - 200°C), and the dehydrogenation heat absorption of H2 in perhydro-N-ethylcarbazole (40 kJ / mol) is less than the hydrogenation heat release of H2 in acetone (70 kJ / mol), the heating jacket 13 does not need to work during the normal operation stage.

[0091] Startup: Before startup, a certain amount of hydrogen and isopropanol are respectively stored in the first buffer tank 8 and the second buffer tank 9. Hydrogen is introduced into the premixing tank 10, and isopropanol is introduced into the direct isopropanol fuel cell to generate electricity through reaction, generating acetone and electric energy. The electric energy is transmitted to the heating jacket 13 to preheat and start the hydrogen transfer reactor 6, and acetone enters the premixing tank 10. Hydrogen and acetone are mixed at a molar ratio of 1:1, pressurized to 2 Mpa by a pump, and enter the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6. Perhydro-N-ethylcarbazole is introduced into the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6 at 1 / 6 of the molar flow rate of acetone.

[0092] Perhydro-N-ethylcarbazole undergoes a dehydrogenation reaction in the dehydrogenation reaction chamber 14, and finally generates N-ethylcarbazole and hydrogen. The chemical equation is:

[0093] C 14 H25 N→C 14 H 13 N + 6H2

[0094] Acetone and hydrogen undergo a hydrogenation reaction in the hydrogenation reaction chamber 15, ultimately producing isopropyl alcohol. The heat released by the reaction provides heat for the dehydrogenation reaction. The isopropyl alcohol is used for direct fuel cell power generation. The chemical equation is as follows:

[0095] C3H6O + H2 → C3H8O

[0096] Operation: After the hydrogen transfer reactor 6 is officially in operation, the heating jacket 13 stops working. The flow rate of fully hydrogenated N-ethylcarbazole with a hydrogen storage capacity of 5.8 wt% is 0.5 mL / min. After being preheated by the first heat exchanger 4 and the second heat exchanger 5, it enters the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6 and contacts the 5 wt% Pd / Al2O3 catalyst in the chamber. A dehydrogenation reaction occurs at 180 °C, generating N-ethylcarbazole and hydrogen. The conversion rate of the dehydrogenation reaction can reach 94.4%. The mixture of N-ethylcarbazole and hydrogen generated by the dehydrogenation reaction enters the gas-liquid separator 7 after heat recovery by the first heat exchanger 4, and is separated into N-ethylcarbazole and hydrogen. The N-ethylcarbazole enters the storage tank 1 for storage, and the hydrogen enters the first buffer tank 8 for storage. The hydrogen from the first buffer tank 8 and the acetone from the direct fuel cell 11 are mixed at a molar ratio of 1:1, and then pumped to 2 Mpa at a flow rate 12 times the molar flow rate of fully hydrogenated N-ethylcarbazole and enter the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6. It contacts the 2 wt% Pd / Al2O3 catalyst in the chamber, and a hydrogenation reaction occurs at 200 °C. The reaction releases heat, and the heat is transferred to the dehydrogenation reaction chamber 14 through heat convection and heat conduction of the porous medium to maintain the high-temperature environment of the dehydrogenation reaction. The hydrogenation reaction produces isopropyl alcohol. The isopropyl alcohol enters the second buffer tank 9 for storage after heat recovery by the second heat exchanger 5, and then enters the direct isopropyl alcohol fuel cell for reaction power generation, generating acetone and electric energy. The electric energy is transferred to the electricity-consuming unit outside 12, and the acetone enters the premixing tank 10 to be mixed with hydrogen and then continues to enter the hydrogen transfer reactor 6 for reaction. Such a cycle continues for power generation.

[0097] No external energy input is required for the whole process. The heat required for the dehydrogenation of fully hydrogenated N-ethylcarbazole is provided by the heat released from the acetone hydrogenation reaction. Acetone / isopropyl alcohol acts as an intermediate medium to combine the fully hydrogenated N-ethylcarbazole with a high hydrogen storage density and the direct isopropyl alcohol fuel cell with high energy efficiency, constructing a sequence of transfer hydrogenation - direct fuel cell, and the overall energy efficiency exceeds 50%.

[0098] Example 2:

[0099] Dibenzyltoluene is selected as organic liquid A, acetone as organic liquid B, direct isopropanol fuel cell as direct fuel cell 11, 0.3wt% Pt / Al2O3 as dehydrogenation catalyst, and 2wt% Ru / AC-ZnO as hydrogenation catalyst. The endothermic heat of H2 dehydrogenation of perhydrodibenzyltoluene (65 kJ / mol) is less than the exothermic heat of H2 hydrogenation of acetone (70 kJ / mol), but the dehydrogenation reaction temperature of perhydrodibenzyltoluene (250 °C - 300 °C) is higher than the hydrogenation reaction temperature of acetone (220 °C - 250 °C). Therefore, the heating jacket 13 still needs to work during the normal operation stage to compensate for the missing heat.

[0100] Startup: Before startup, a certain amount of hydrogen and isopropanol are stored in the first buffer tank 8 and the second buffer tank 9 respectively. Hydrogen is introduced into the premixing tank 10, and isopropanol is introduced into the direct isopropanol fuel cell for reaction to generate electricity, producing acetone and electric energy. The electric energy is transferred to the heating jacket 13 to preheat and start the hydrogen transfer reactor 6, and acetone enters the premixing tank 10. Hydrogen and acetone are mixed in a molar ratio of 1:1 and pressurized to 2 Mpa by a pump, then enter the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6. Perhydrodibenzyltoluene is introduced into the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6 at a flow rate of 1 / 9 of the acetone molar flow rate.

[0101] Perhydrodibenzyltoluene undergoes a dehydrogenation reaction in the dehydrogenation reaction chamber 14, finally generating dibenzyltoluene and hydrogen. The chemical equation is:

[0102] C 21 H 38 →C 21 H 20 +9H2

[0103] Acetone and hydrogen undergo a hydrogenation reaction in the hydrogenation reaction chamber 15, finally generating isopropanol. The heat released by the reaction provides heat for the dehydrogenation reaction, and isopropanol is used for power generation in the direct isopropanol fuel cell. The chemical equation is:

[0104] C3H6O + H2 → C3H8O

[0105] Operation: After the hydrogen transfer reactor 6 is officially put into operation, the heating jacket 13 continues to work to supplement the missing heat. The flow rate of perhydrodibenzyltoluene with a hydrogen storage capacity of 6.2 wt% is 5 mL / min. After being preheated by the first heat exchanger 4 and the second heat exchanger 5, it is introduced into the dehydrogenation reaction chamber 14 of the hydrogen transfer reactor 6 and contacts the 0.3 wt% Pt / Al2O3 catalyst in the chamber. A dehydrogenation reaction occurs at 300 °C to produce dibenzyltoluene and hydrogen. The conversion rate of the dehydrogenation reaction can reach 90%. The mixture of dibenzyltoluene and hydrogen generated by the dehydrogenation reaction enters the gas-liquid separator 7 after the waste heat recovery of the first heat exchanger 4, and is separated into dibenzyltoluene and hydrogen. The dibenzyltoluene enters the storage tank 1 for storage, and the hydrogen enters the first buffer tank 8 for storage. The hydrogen from the first buffer tank 8 and acetone from the direct fuel cell 11 are mixed at a molar ratio of 1:1, and then pressurized to 2 Mpa by a pump at a flow rate 18 times the molar flow rate of perhydrodibenzyltoluene and introduced into the hydrogenation reaction chamber 15 of the hydrogen transfer reactor 6. It contacts the 2 wt% Ru / AC-ZnO catalyst in the chamber, and a hydrogenation reaction occurs at 250 °C. The reaction releases heat, and the heat is transferred to the dehydrogenation reaction chamber 14 through heat convection and heat conduction of the porous medium. The hydrogenation reaction produces isopropanol. The isopropanol enters the second buffer tank 9 for storage after the waste heat recovery of the second heat exchanger 5, and then enters the direct isopropanol fuel cell to generate electricity, producing acetone and electric energy. The acetone enters the premixing tank 10 to be mixed with hydrogen and then continues to enter the hydrogen transfer reactor 6 for reaction. The electric energy is transferred to the electricity-consuming units outside 12 and the heating jacket 13. Since the heat released by the hydrogenation reaction is not enough to maintain the high-temperature environment required for the dehydrogenation reaction, about 20% of the electric energy flows to the heating jacket 13 to heat the hydrogen transfer reactor 6.

[0106] No external energy input is required for the whole process. The heat required for the dehydrogenation of perhydrodibenzyltoluene is provided by the acetone hydrogenation reaction and the heating jacket 13. In this example, part of the electric energy needs to be consumed to supply heat for the dehydrogenation reaction, which will reduce the overall energy efficiency of the system. Therefore, an organic liquid with a low dehydrogenation temperature and low energy consumption is preferably used as organic liquid A.

[0107] It should be noted that the various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other.

[0108] It should also be noted that in this text, the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, relative terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations, nor can they be construed as indicating or implying relative importance. Moreover, the term "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or terminal device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or terminal device.

[0109] The above has introduced in detail a direct fuel cell system based on organic liquid hydrogen transfer provided by the present application. Specific examples are used in this text to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only for helping to understand the present application, and the content of this specification should not be construed as a limitation to the present application. At the same time, for those of ordinary skill in the art, according to the present application, there will be various forms of changes in the specific implementation manner and application scope. It is not necessary and impossible to list all the implementation manners here, and the obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A direct fuel cell system based on organic liquid hydrogen transfer, characterized in that the system Comprising: An organic liquid A module, including a hydrogen-carrying part for storing and transporting organic liquid A; the organic liquid A includes hydrogen-rich organic liquid A and hydrogen-lean organic liquid A; An organic liquid B module, including a direct fuel cell and organic liquid B; the organic liquid B includes hydrogen-rich organic liquid B and hydrogen-lean organic liquid B; wherein, the direct fuel cell is used to receive and directly generate electricity using hydrogen-rich organic liquid B to generate hydrogen-lean organic liquid B; Wherein, the hydrogen storage density of the organic liquid A is greater than that of the organic liquid B; A hydrogen transfer reactor, including a dehydrogenation reaction chamber and a hydrogenation reaction chamber; The dehydrogenation reaction chamber is communicated with the hydrogen-carrying part, and is used to receive the hydrogen-rich organic liquid A transported from the hydrogen-carrying part, carry out dehydrogenation reaction to generate hydrogen-lean organic liquid A and hydrogen, and jointly transport them to the hydrogen-carrying part; The hydrogenation reaction chamber is communicated with the direct fuel cell and is also communicated with the hydrogen-carrying part, and is used to receive the hydrogen-lean organic liquid B after the direct fuel cell generates electricity and the hydrogen output from the hydrogen-carrying part, carry out hydrogenation reaction to generate hydrogen-rich organic liquid B, so that the hydrogen in the organic liquid A is transferred to the organic liquid B; Wherein, the dehydrogenation reaction chamber and the hydrogenation reaction chamber are in contact with each other, so that the heat generated by the hydrogenation reaction in the hydrogenation reaction chamber is transferred to the dehydrogenation reaction chamber to supply heat for the dehydrogenation reaction.

2. The direct fuel cell system based on organic liquid hydrogen transfer according to claim 1, characterized in that, The dehydrogenation reaction chamber is sleeved on the outer periphery of the hydrogenation reaction chamber, and porous media are respectively filled in the dehydrogenation reaction chamber and the hydrogenation reaction chamber, and the porous media are used to load catalysts and strengthen mass transfer and heat transfer.

3. A direct fuel cell system based on organic liquid hydrogen transfer according to claim 1, characterized in that, The hydrogen transfer reactor further includes a heating jacket sleeved on the outer periphery of the dehydrogenation reaction chamber; Wherein, the heating jacket is electrically connected to the direct fuel cell to compensate for the heat required for the dehydrogenation reaction in the dehydrogenation reaction chamber under demand working conditions.

4. A direct fuel cell system based on organic liquid hydrogen transfer according to claim 1, characterized in that, The hydrogen-carrying part includes: A storage tank, including a hydrogen-rich organic liquid A storage chamber and a hydrogen-lean organic liquid A storage chamber that are independent of each other, the hydrogen-rich organic liquid A storage chamber stores the hydrogen-rich organic liquid A, and the hydrogen-lean organic liquid A storage chamber stores the hydrogen-lean organic liquid A; A heat exchanger group, including a first heat exchanger and / or a second heat exchanger; wherein, The first heat exchanger is respectively communicated with the hydrogen-rich organic liquid A storage chamber and the dehydrogenation reaction chamber, and is used to recover the waste heat of the dehydrogenation reaction product to preheat the hydrogen-rich organic liquid A; and / or, the second heat exchanger is respectively communicated with the hydrogen-rich organic liquid A storage chamber and the hydrogenation reaction chamber, and is used to recover the waste heat of the hydrogenation reaction product to preheat the hydrogen-rich organic liquid A; and, the second heat exchanger is also communicated with the dehydrogenation reaction chamber, and is used to input the preheated hydrogen-rich organic liquid A into the dehydrogenation reaction chamber; A gas-liquid separator, which is respectively communicated with the first heat exchanger, the hydrogen-lean organic liquid A storage chamber and the hydrogenation reaction chamber, or respectively communicated with the hydrogen-lean organic liquid A storage chamber and the hydrogenation reaction chamber, and is used to receive and separate the dehydrogenation reaction product, return the hydrogen-lean organic liquid A to the hydrogen-lean organic liquid A storage chamber, and at the same time transport the hydrogen to the hydrogenation reaction chamber.

5. A direct fuel cell system based on organic liquid hydrogen transfer according to claim 4, characterized in that, The heat exchanger group includes a first heat exchanger and a second heat exchanger, and the first heat exchanger and the second heat exchanger are connected to preheat the hydrogen-rich organic liquid A at the first stage by using the first heat exchanger, and at the same time preheat the hydrogen-rich organic liquid A after the first-stage preheating by using the second heat exchanger.

6. A direct fuel cell system based on organic liquid hydrogen transfer according to claim 4 or 5, characterized in that, The organic liquid A module further includes: A first buffer tank, which is connected to the gas-liquid separator and is used for receiving the hydrogen; A premixing tank, which is respectively connected to the first buffer tank, the direct fuel cell and the hydrogenation reaction chamber, and is used for mixing the hydrogen and the hydrogen-deficient organic liquid B and transporting the mixture obtained by mixing to the hydrogenation reaction chamber.

7. A direct fuel cell system based on organic liquid hydrogen transfer according to claim 4 or 5, characterized in that, The organic liquid B module further includes: A second buffer tank, which is respectively connected to the direct fuel cell and the second heat exchanger, and is used for receiving the hydrogen-rich organic liquid B output by the second heat exchanger and transporting it into the direct fuel cell.

8. A direct fuel cell system based on organic liquid hydrogen transfer according to claim 2, characterized in that, The porous medium includes any one of foam metal, metal fiber sintered material and ceramic foam; and / or, the catalyst loaded in the hydrogenation reaction chamber includes any one of platinum, ruthenium and palladium; the catalyst loaded in the dehydrogenation reaction chamber includes any one of platinum, palladium and rhodium.

9. The direct fuel cell system based on organic liquid hydrogen transfer according to claim 1, characterized in that, The direct fuel cell is an organic liquid B fuel cell, which is used for directly using the hydrogen-rich organic liquid B as an anode reactant and using air or oxygen as a cathode reactant at the same time.

10. A direct fuel cell system based on organic liquid hydrogen transfer according to claim 1, characterized in that, The organic liquid A includes one or a mixture of several of toluene, biphenyl, naphthalene, ethylcarbazole, N-ethylcarbazole, dibenzyltoluene, indole, quinoline, phenazine, 2-methylquinoline and N-methylindole; and / or, the organic liquid B includes at least one of saturated ketone and methanol.

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