An integrated shipboard power plant of hydrogen production micro-reactor coupled with fuel cell

Abstract

The present application relates to the field of ship energy power and technology, disclose a kind of integrated shipboard power plant of hydrogen microreactor coupling fuel cell, to build seawater methanol reforming coupling fuel cell integrated system, provide new ideas for marine ship low-carbon energy use and green navigation.The integrated shipboard power plant of methanol photo-thermal continuous hydrogen production microreactor coupling fuel cell provided by the present application includes series liquid storage tank, injection pump, microchannel reactor, gas-liquid separator, proton exchange membrane fuel cell and motor, the liquid of gas-liquid separator is sent to the inlet of microchannel reactor, and the positive electrode gas outlet of proton exchange membrane fuel cell leads to liquid storage tank.The present application utilizes seawater to produce hydrogen on site, enhances the endurance of ship navigation, and compared with traditional diesel direct combustion, the established "methanol+seawater→hydrogen→green electricity" cascade conversion has higher energy conversion efficiency.

Description

Technical Field

[0001] This invention relates to the field of marine energy and power technology, and to an integrated marine power unit consisting of a hydrogen production microreactor coupled with a fuel cell. More specifically, it relates to an integrated marine power unit consisting of a methanol photothermal continuous hydrogen production microreactor coupled with a fuel cell. Background Technology

[0002] With the rapid depletion of fossil fuels, hydrogen energy has become a green and environmentally friendly energy source in the eyes of the future. Fuel cells can directly convert chemical energy into electrical energy by combining hydrogen and oxygen in a simple electrochemical device, thus providing clean and efficient electricity. However, the production, transportation, and storage of hydrogen still face several challenges. Methanol, due to its convenient transportation, high energy density, and low conversion temperature, is considered an important liquid fuel for hydrogen storage, transportation, and production. Therefore, the coupling of methanol reforming for hydrogen production with fuel cell systems can achieve on-demand hydrogen production.

[0003] The main technical routes for methanol reforming to produce hydrogen include methanol steam reforming, partial oxidative reforming, oxidative steam reforming, and adsorption-enhanced reforming. Among these, methanol steam reforming has become the mainstream route due to its mild reaction conditions and high hydrogen production efficiency, but it still suffers from problems such as system complexity, long start-up time, and the presence of CO and CO2 as reaction byproducts. Traditional proton exchange membrane fuel cells (PEMFCs) with bipolar plates in the direct-current channel may face challenges related to uneven gas distribution, while serpentine flow channels present challenges such as high pressure drop and energy consumption, uneven current density distribution, and localized water management.

[0004] Based on the above analysis, an integrated marine propulsion system that can simultaneously balance performance and efficiency is urgently needed in the industry. Summary of the Invention

[0005] In view of the above shortcomings, the present invention provides an integrated marine power system and device that combines a methanol photothermal continuous hydrogen production microreactor with a proton exchange membrane fuel cell, realizing the series conversion of seawater + methanol → hydrogen → electricity under light-assisted conditions, enabling the fuel cell system based on methanol reforming to achieve low carbon and zero pollution emissions as well as high-efficiency energy utilization.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] This invention first discloses an integrated marine propulsion device with a microreactor coupled to a fuel cell, and the connections and material flow relationships of the various components are as follows: Figure 1-2 As shown, it includes:

[0008] A methanol photothermal reforming hydrogen production unit (1) and a proton exchange membrane fuel cell unit (2); wherein:

[0009] The methanol photothermal reforming hydrogen production unit (1) includes: a mixer (14), a microchannel reactor (15), and a gas-liquid separator (17);

[0010] The upper and lower ends of one side of the mixer (14) are connected to a mass flow meter (13) and an injection pump (11), respectively. The mass flow meter (13) is connected to a nitrogen cylinder (12), and the injection pump (11) is connected to a storage tank (18).

[0011] The proton exchange membrane fuel cell unit (2) includes: a proton exchange membrane fuel cell (21);

[0012] The proton exchange membrane fuel cell (21) is connected to the gas-liquid separator (17) through the negative electrode inlet (25), and its positive electrode inlet (26) is connected to the air pump (24); the negative electrode exhaust gas (29) is discharged through the negative electrode outlet (27), and the positive electrode outlet (28) returns to the injection pump (11) through the liquid storage tank (18) for recycling;

[0013] The proton exchange membrane fuel cell (21) is also equipped with a DC / AC converter (22) and an electric motor (23).

[0014] Furthermore, the methanol photothermal reforming hydrogen production unit (1) and the proton exchange membrane fuel cell unit (2) both operate at a temperature of 80-90℃.

[0015] Furthermore, the reaction products of the microchannel reactor (15) are passed through a gas-liquid separator (17) via a conduit and then to the negative electrode inlet (25) of the proton exchange membrane fuel cell (21).

[0016] The liquid collected by the gas-liquid separator (17) is sent to the microchannel reactor (15) for recycling.

[0017] The gas discharged from the positive electrode outlet (28) of the proton exchange membrane fuel cell (21) is directed to the liquid storage tank (18) to realize the utilization of the reaction products of the proton exchange membrane fuel cell.

[0018] Furthermore, the microchannel reactor (15) is composed of a microchannel nickel plate (151), two transparent quartz plates (152) and two sealing rubber gaskets (153) connected by a bolt assembly (154), and the microchannel is a serpentine flow channel;

[0019] The proton exchange membrane fuel cell (21) is composed of a negative electrode plate (211), a hydrogen diffusion layer (212), a negative electrode catalyst layer (213), a proton exchange membrane (214), a positive electrode catalyst layer (215), an oxygen diffusion layer (216), and a positive electrode plate (217); the negative electrode plate (211) and the positive electrode plate (217) are connected by a bolt assembly; and both the negative electrode plate (211) and the positive electrode plate (217) have a tree-like fractal biomimetic flow channel.

[0020] Furthermore, the serpentine flow channel is composed of several straight flow channel segments that are connected end to end and are parallel to each other;

[0021] The tree-like fractal biomimetic flow channel is composed of symmetrical Y-shaped branches with a double-branch structure. The inlet flow channel width is 3.12 mm, and the end is connected to a parallel flow channel array. The flow channel width at each branch node decreases step by step according to the cubic relationship of Murray's law.

[0022] Furthermore, the flow channel width at each branch node decreases progressively according to the cubic relationship of Murray's law, including: each main flow channel decreasing at a ratio of 1:2. 1 / 3 The proportion is split into two sub-channels.

[0023] Furthermore, the hydrogen production catalyst is fixed on the inner wall of the upper channel of the microchannel nickel plate (151) by a polydopamine coating.

[0024] Furthermore, the step of immobilizing the hydrogen production catalyst on the inner wall of the microchannel nickel plate (151) through a polydopamine coating includes:

[0025] (1) The microchannel nickel plate 151 was cleaned in an ultrasonic oscillator for 30 min at room temperature, and then dried in a drying oven at 80°C for 30 min.

[0026] (2) The microchannel nickel plate 151 was vertically immersed in the dopamine reaction solution for 12 hours. The resulting polydopamine-coated substrate was ultrasonically cleaned with deionized water for 30 seconds, and then dried with nitrogen and stored.

[0027] (3) Use a syringe to evenly inject the catalyst slurry into the microchannel treated in step (2), dry the coated microchannel nickel plate 151 at room temperature for 12 hours, and then put it into a drying oven at 180°C for 3 hours to obtain the product.

[0028] Further, the dopamine reaction solution in step (2) is prepared by the following method:

[0029] Prepare a dopamine reaction solution with a dopamine concentration of 2 mg / mL and pH = 8.5 using dopamine, Tris, and deionized water for later use.

[0030] Further, the catalyst slurry in step (3) is prepared by the following method:

[0031] The catalyst and polyvinyl alcohol were mixed at a mass ratio of 1:4 to prepare a 5% mass fraction solution. The solution was treated with an ultrasonic oscillator at room temperature for 30 min, and then stirred at room temperature for 6 h to obtain a catalyst slurry for later use.

[0032] Furthermore, the hydrogen production catalyst is a Cu2O@ZnIn2S4 catalyst with a core-shell structure. The ZnIn2S4 shell isolates impurity ion penetration, while the core Cu2O nanoparticles convert light energy into heat energy through the LSPR effect.

[0033] Furthermore, the microchannel nickel plate (151) is filled with a mixed solution of methanol and seawater containing chloride ions.

[0034] Compared with the prior art, the advantages of the present invention are as follows:

[0035] This invention provides a novel approach to coupling hydrogen production through reforming and fuel cell power generation. The hydrogen production unit uses locally sourced seawater and shipborne methanol as reactants, continuously producing hydrogen via solar photothermal catalysis in a microchannel reactor. After gas-liquid separation, unreacted liquid is recycled, and the hydrogen is fed into the fuel cell unit to generate electricity for the ship. Simultaneously, water generated during battery operation can be recycled back to the hydrogen production unit, achieving the integrated utilization of abundant marine resources and solar energy, converting them into stable green hydrogen electricity to power the ship's navigation. Specifically, the advantages are:

[0036] 1. The integrated marine power system and device of the present invention, compared with the traditional marine power system, rationally couples the reforming reactor and the fuel cell, and constructs a methanol + seawater → hydrogen → green elevator conversion path using methanol and seawater as raw materials. This realizes the local sourcing of raw materials and the on-demand production and use of hydrogen, solves the storage and transportation problems of raw materials and hydrogen, and the whole process is clean, safe and efficient, reducing the cost of power fuel.

[0037] 2. Compared with traditional fixed-bed reaction systems, the microchannel reactor of the present invention performs mobile phase circulation reaction, which improves mass and heat transfer efficiency and raw material utilization. Compared with traditional thermocatalytic steam reforming, it reduces the number of raw material vaporization units, reduces energy consumption, and strengthens the WGSR process in the reforming process, effectively suppressing the generation of by-product CO.

[0038] 3. The Cu2O@ZnIn2S4 core-shell catalytic system constructed in this invention allows Cu2O nanoparticles to generate hot electrons under photoexcitation, promoting the separation of photogenerated carriers; ZnIn2S4 possesses advantages such as a small band gap and broad photoresponse characteristics. The two components synergistically activate methanol and water molecules, achieving the goal of solar-driven catalytic reaction. This two-component photothermal catalysis avoids the problems of high temperature and high byproduct yield associated with traditional thermocatalysis, while overcoming the low efficiency of conventional single-component photocatalysis, thus ensuring efficient and highly selective hydrogen production at low temperatures. The core-shell structure can prevent corrosion from seawater impurity ions and reduce the loss of active components, improving the catalyst's catalytic efficiency and durability.

[0039] 4. The polydopamine-assisted catalyst coating process provided by the present invention utilizes PDA biomimetic adhesion and PVA crosslinking network to coat and form a porous shear-resistant catalyst layer in the microchannel, which enhances the anchoring strength and dispersibility of nanocatalyst particles, solves the problem of easy catalyst detachment in the mobile phase reaction, improves the long-term stability of the microchannel reaction system and takes into account the mass transfer efficiency.

[0040] 5. This invention addresses the problems of uneven gas distribution, flooding, and large pressure drop inherent in traditional parallel flow channels of proton exchange membrane fuel cells. It designs a tree-like fractal biomimetic flow channel structure, actively optimizing specific geometric parameters to improve the uniformity of oxygen and water distribution and reduce pressure drop, thereby enhancing the battery's output power and stability. A performance comparison between this system and a diesel system is provided. Figure 7 As shown. Attached Figure Description

[0041] Figure 1 The diagram shows an integrated marine power unit with a microreactor coupled to a fuel cell according to the present invention. The names of the components are: methanol photothermal reforming hydrogen production unit (1) and proton exchange membrane fuel cell unit (2).

[0042] Injection pump (11), nitrogen cylinder (12), mass flow meter (13), mixer (14), microchannel reactor (15), xenon lamp light source (16), gas-liquid separator (17), liquid storage tank (18);

[0043] Proton exchange membrane fuel cell (21), DC / AC converter (22), electric motor (23), air pump (24), negative electrode inlet (25), positive electrode inlet (26), negative electrode outlet (27), positive electrode outlet (28), negative electrode exhaust gas (29).

[0044] Figure 2 This is a schematic diagram of the energy and material flow of the integrated marine propulsion system combining a methanol photothermal continuous hydrogen production microreactor and a proton exchange membrane fuel cell, according to the present invention.

[0045] Figure 3 This is a partial schematic diagram of the microchannel reactor (15). The main components are: microchannel nickel plate (151), two transparent quartz plates (152), sealing rubber gasket (153), and bolt assembly (154).

[0046] Figure 4 This is a partial schematic diagram of a proton exchange membrane fuel cell (21). The main components are: negative electrode plate (211), hydrogen diffusion layer (212), negative electrode catalyst layer (213), proton exchange membrane (214), positive electrode catalyst layer (215), oxygen diffusion layer (216), and positive electrode plate (217).

[0047] Figure 5This is a diagram of a tree-like fractal flow channel structure.

[0048] Figure 6 Flowchart for the preparation of Cu2O@ZnIn2S4 hydrogen production catalyst.

[0049] Figure 7 This is a performance comparison chart between this system and the diesel system.

[0050] Figure 8 This is a comparison of hydrogen production rates in a methanol photothermal reforming hydrogen production unit under different chloride ion concentrations and catalyst types.

[0051] Figure 9 This is a comparison of the hydrogen production rates of a methanol photothermal reforming hydrogen production unit at 90°C under illumination and without illumination. Detailed Implementation

[0052] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0053] This invention discloses an integrated marine propulsion system for continuous methanol photothermal hydrogen production via a microreactor coupled with a fuel cell, such as... Figure 1 As shown, it includes: methanol photothermal continuous reforming hydrogen production unit 1 and proton exchange membrane fuel cell unit 2.

[0054] Furthermore, the methanol photothermal continuous reforming hydrogen production unit 1 includes: an injection pump 11, a nitrogen cylinder 12, a mass flow meter 13, a mixer 14, a microchannel reactor 15, a xenon lamp light source 16, a gas-liquid separator 17, and a storage tank 18.

[0055] Furthermore, the proton exchange membrane fuel cell unit 2 includes: a proton exchange membrane fuel cell 21, a DC / AC converter 22, an electric motor 23, an air pump 24, a negative electrode inlet 25, a positive electrode inlet 26, a negative electrode outlet 27, and a positive electrode outlet 28.

[0056] Furthermore, the injection pump 11 delivers the methanol-seawater solution to the microchannel reactor 15 via a delivery pipeline, while the nitrogen cylinder 12 delivers nitrogen via a delivery pipeline. The nitrogen flow rate is controlled by a mass flow meter 13. After passing through a mixer 14, the nitrogen and methanol-seawater solution are mixed and delivered to the inlet of the microchannel reactor 15. A xenon lamp light source 16 simulates sunlight irradiation to drive the reaction in the microchannel reactor. The reaction residue and products are delivered from the outlet to a gas-liquid separator 17 under the pressure of the nitrogen flow. Unreacted residue is separated from hydrogen. The unreacted residue is stored in the gas-liquid separator 17 for later recycling to the microreactor 15. Hydrogen is sent to the proton exchange membrane fuel cell unit 2. Gas enters the negative electrode of the proton exchange membrane fuel cell 21, while air enters the positive electrode. After catalysis by the catalyst, unreacted hydrogen is discharged from the negative electrode, and water and air are discharged from the positive electrode. The water is stored in a storage tank 18 for recycling. The energy and material flow of this system is as follows: Figure 2 As shown.

[0057] In this embodiment, the microchannel reactor 15 mainly consists of a microchannel nickel plate 151, two transparent quartz plates 152, two sealing rubber gaskets 153, and a bolt assembly 154. Figure 3 As shown.

[0058] In this embodiment, the proton exchange membrane fuel cell 21 mainly consists of a negative electrode plate 211, a hydrogen diffusion layer 212, a negative electrode catalyst layer 213, a proton exchange membrane 214, a positive electrode catalyst layer 215, an oxygen diffusion layer 216, and a positive electrode plate 217. Figure 4 As shown. At the negative electrode, hydrogen oxidation occurs: 2H₂ → 4H₂ + +4e - The generated H + Oxygen diffuses through the proton exchange membrane 214 into the positive electrode of the proton exchange membrane fuel cell 21, where it undergoes a reduction reaction: O2 + 4H+ + +4e - →2H2O, the electrical energy generated by the proton exchange membrane fuel cell 21 is drawn out by the electrodes to the electric motor 23.

[0059] In this embodiment, the flow channels of the negative electrode plate 211 and the positive electrode plate 217 adopt a tree-like fractal flow channel structure. For example... Figure 5 As shown, the tree-like fractal flow channel consists of several symmetrically connected flow channel branches in a multi-level bifurcation pattern. The bifurcation nodes are constructed with fractal geometry based on Murray's law, and each parent flow channel is designed at a 1:2 ratio. 1 / 3The flow path is proportionally split into two sub-channels. Compared with conventional parallel channels, its fractal topology network significantly increases the fluid contact interface. The progressively decreasing channel cross-sectional dimensions guide the fluid to form a self-similar flow distribution. The unique bifurcation structure induces secondary flow and stratified flow effects, which not only enhances the gas-liquid-solid three-phase contact efficiency, but also reduces the system pressure drop to 48% of that of traditional serpentine channels through channel impedance matching, thus achieving synergistic enhancement of heat and mass transfer.

[0060] In this embodiment, the process flow for preparing the Cu2O@ZnIn2S4 catalyst is as follows: Figure 6 As shown, the specific steps include:

[0061] Step 1: Preparation of Cu2O nanoboxes

[0062] Weigh 1.5 mmol CuSO4·5H2O and 0.5 mmol sodium citrate and add them to 80 mL of deionized water, stirring for 15 min. Add 20 mL of 1.25 M sodium hydroxide solution to the above solution and stir again for 15 min, then add 50 mL of ascorbic acid. Let the resulting solution stand at room temperature for 1 h to age. Finally, collect the precipitate by centrifugation and wash several times with deionized water and anhydrous ethanol.

[0063] Step 2: Preparation of Cu2O@ZnIn2S4

[0064] 200 mg of pre-prepared Cu₂O was weighed and added to 40 mL of anhydrous ethanol, and treated with an ultrasonic oscillator for 30 min. Then, 1 mmol ZnCl₂, 2 mmol InCl₃·4H₂O, and 8 mmol thioacetamide were added to this suspension, and the mixture was stirred vigorously for 30 min. The resulting mixture was placed in a sealed polytetrafluoroethylene-lined autoclave and kept at 120 °C for 2 h. The product was washed several times with deionized water and anhydrous ethanol, and extracted by centrifugation. Finally, the product was dried at 60 °C for 10 h to obtain the Cu₂O@ZnIn₂S₄ composite product.

[0065] In this embodiment, the process of fixing the catalyst on the microchannel nickel plate 151 of the microchannel reactor 15 specifically includes the following steps:

[0066] Step 1: Place the microchannel nickel plate 151 in an ultrasonic oscillator for cleaning at room temperature for 30 minutes, and then place it in a drying oven at 80°C for 30 minutes.

[0067] Step 2: Prepare a dopamine reaction solution with a dopamine concentration of 2 mg / mL and pH = 8.5 using dopamine, Tris, and deionized water. Immerse the microchannel nickel plate 151 vertically in the solution for 12 hours, stirring occasionally to prevent non-specific particle deposition that could increase coating roughness or generate impurities. The resulting polydopamine-coated substrate is then ultrasonically cleaned with deionized water for 30 seconds, dried with nitrogen, and stored.

[0068] Step 3: Prepare a 5% (w / w) solution of catalyst and polyvinyl alcohol at a mass ratio of 1:4, treat with an ultrasonic oscillator at room temperature for 30 min, and then stir at room temperature for 6 h.

[0069] Step 4: During the coating process, the catalyst slurry is evenly injected into the microchannels using a syringe. The coated microchannel nickel plate 151 is dried at room temperature for 12 hours, and then placed in a drying oven at 180°C for 3 hours to increase the strength of the catalyst coating.

[0070] This approach offers the following advantages:

[0071] First, the biomimetic adhesion mechanism of the coating can improve the firmness of the catalyst fixation and prevent it from easily falling off due to fluid shear in the channel;

[0072] Second, it enhances the dispersibility of the fixed catalyst, and the porous structure of the coating prevents catalyst agglomeration.

[0073] In this embodiment, the process for preparing the Pt / C catalyst specifically includes the following steps:

[0074] Step 1: Carrier pre-activation

[0075] Carbon black was calcined in N2 at 873 K for 30 min and then used as a support to prepare a Pt / C catalyst.

[0076] Step 2: Precursor impregnation

[0077] Add 5 mL of water and 5 mL of isopropanol to 200 mg of carbon black, and then sonicate the suspension for 15 min. Add 5 mL of H2PtO6 aqueous solution with a platinum concentration of 0.01 g / mL to the suspension and sonicate for 30 min. Then adjust the pH of the suspension to 8-9 by adding 1 mol / mL Na2CO3 aqueous solution.

[0078] Step 3: Post-restore processing

[0079] Under stirring, excess formaldehyde aqueous solution reducing agent was slowly added to the suspension over 1 hour, and then stirred for 2 hours; the suspension was filtered off, the product was washed several times with deionized water, and then dried in a vacuum drying oven at 80°C for 6 hours.

[0080] Experimental Example 1

[0081] Evaluation of the effect of photothermal catalytic methanol reforming for hydrogen production

[0082] A microchannel reactor 15, in which 100 mg of a core-shell catalyst was coated on the wall of a microchannel nickel plate 151, was purged with a methanol-water solution and nitrogen gas. The water-to-methanol ratio in the methanol-water solution was 1.5, the flow rate was 0.2 mL / min, and the nitrogen gas flow rate was 40 mL / min. A xenon lamp was turned on to ensure sufficient and uniform illumination of the reactor. The temperature was recorded using thermocouples, and the reaction pressure was atmospheric pressure. The hydrogen yield results are shown in […]. Figure 8 Photothermal catalysis achieved a hydrogen production rate of 1016 μmol·g at 90 °C. -1 ·h -1 Conclusion: Photothermal synergy improves efficiency compared to single thermocatalysis due to the enhanced photothermal conversion effect of the Cu2O@ZnIn2S4 core-shell structure.

[0083] Experimental Example 2

[0084] Evaluation of the effect of thermocatalytic methanol reforming on hydrogen production

[0085] 30 mL of methanol-water solution (water-to-ethanol ratio 1.5) and 50 mg of core-shell catalyst were added to a hydrothermal reactor. The mixture was heated to 90 °C with continuous stirring. The hydrogen yield results are shown in [Figure Number]. Figure 8 Thermocatalytic hydrogen production rate is only 89 μmol·g -1 ·h -1 Conclusion: The reaction efficiency is low in the absence of light.

[0086] The performance comparison between Experimental Example 1 and Experimental Example 2 shows that, at the same temperature, the photothermal synergistic catalysis efficiency is better than that of single thermal catalysis.

[0087] Experimental Example 3

[0088] Evaluation of catalyst resistance to Cl - Ion poisoning performance

[0089] The only difference from Example 1 is that the aqueous solution contains different concentrations of Cl. - .

[0090] A microchannel reactor 15, in which 100 mg of a core-shell catalyst was coated on the wall of a microchannel nickel plate 151, was purged with a methanol-water solution and nitrogen gas. The water-to-methanol ratio in the methanol-water solution was 1.5, the flow rate was 0.2 mL / min, and the nitrogen gas flow rate was 40 mL / min. A xenon lamp was turned on to ensure sufficient and uniform illumination of the reactor. The temperature was recorded using thermocouples, and the reaction pressure was atmospheric pressure. The hydrogen yield results are shown in […]. Figure 9 When the Cl- concentration is 0-30 g / L, the core-shell catalyst stabilizes hydrogen production at 925-1025 μmol·g⁻¹. -1 ·h-1 Conclusion: The ZnIn2S4 shell effectively isolates impurity ions.

[0091] Comparative Example 1

[0092] Compared with Experimental Example 3, the only difference is that a core-shell catalyst was not used, but a conventional non-core-shell catalyst was used.

[0093] A methanol-water solution and nitrogen gas were introduced into a microchannel reactor (15) with 100 mg of a non-core-shell catalyst coated on the channel wall of a microchannel nickel plate (151). The water-to-methanol ratio in the methanol-water solution was 1.5:1, the flow rate was 0.2 mL / min, and the nitrogen gas flow rate was 40 mL / min. A xenon lamp was turned on to ensure that the reactor was fully and uniformly illuminated. The temperature was recorded using thermocouples, and the reaction pressure was atmospheric pressure. The hydrogen yield results are shown in […]. Figure 9 As the Cl- concentration increases, the hydrogen production rate decreases to 600 μmol·g. -1 ·h -1 Conclusion: Non-core-shell catalysts are susceptible to ion poisoning.

[0094] The above embodiments are merely illustrative examples to clearly illustrate the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An integrated marine propulsion system with a microreactor coupled to a fuel cell, comprising: The following components are connected in sequence: a mixer (14), a microchannel reactor (15), a gas-liquid separator (17), and a proton exchange membrane fuel cell (21); wherein: The upper and lower ends of one side of the mixer (14) are connected to a mass flow meter (13) and an injection pump (11), respectively. The mass flow meter (13) is connected to a nitrogen cylinder (12), and the injection pump (11) is connected to a storage tank (18). A xenon lamp light source (16) is installed on the upper side of the microchannel reactor (15); The proton exchange membrane fuel cell (21) is connected to the gas-liquid separator (17) through the negative electrode inlet (25), and its positive electrode inlet (26) is connected to the air pump (24); the negative electrode exhaust gas (29) is discharged through the negative electrode outlet (27), and the positive electrode outlet (28) is connected to the liquid storage tank (18) and the injection pump (11) to recycle the battery reaction products; The proton exchange membrane fuel cell (21) is also equipped with a DC / AC converter (22) and an electric motor (23); The reaction products of the microchannel reactor (15) are passed through a gas-liquid separator (17) via a conduit and then to the negative electrode inlet (25) of the proton exchange membrane fuel cell (21). The liquid collected by the gas-liquid separator (17) is sent to the microchannel reactor (15) for recycling. The gas discharged from the positive electrode outlet (28) of the proton exchange membrane fuel cell (21) is directed to the liquid storage tank (18) to realize the recycling of the reaction products of the proton exchange membrane fuel cell; The microchannel reactor (15) is composed of a microchannel nickel plate (151), two transparent quartz plates (152) and two sealing rubber gaskets (153) connected by a bolt assembly (154). The microchannel is a serpentine flow channel. The proton exchange membrane fuel cell (21) is composed of a negative electrode plate (211), a hydrogen diffusion layer (212), a negative electrode catalyst layer (213), a proton exchange membrane (214), a positive electrode catalyst layer (215), an oxygen diffusion layer (216), and a positive electrode plate (217); the negative electrode plate (211) and the positive electrode plate (217) are connected by a bolt assembly; and both the negative electrode plate (211) and the positive electrode plate (217) have a tree-like fractal biomimetic flow channel.

2. The integrated marine propulsion system with microreactor coupled fuel cell according to claim 1, wherein: The serpentine flow channel is composed of several straight flow channel segments that are connected end to end and are parallel to each other. The tree-like fractal biomimetic flow channel is composed of symmetrical Y-shaped branches with a double-branch structure. The inlet flow channel width is 3.12 mm, and the end is connected to a parallel flow channel array. The flow channel width at each branch node decreases step by step according to the cubic relationship of Murray's law.

3. The integrated marine propulsion system with microreactor coupled fuel cell according to claim 1, wherein: The channel width at each branch node decreases progressively according to the cubic relationship of Murray's law, including: each main channel decreasing by 1: The proportion is split into two sub-channels.

4. The integrated marine propulsion system with microreactor coupled fuel cell according to claim 1, wherein: The inner wall of the microchannel nickel plate (151) is immobilized with a hydrogen production catalyst by a polydopamine coating.

5. The integrated marine propulsion system with microreactor coupled fuel cell according to claim 4, wherein: The step of immobilizing the hydrogen production catalyst on the inner wall of the microchannel nickel plate (151) with a polydopamine coating includes: (1) The microchannel nickel plate (151) was cleaned in an ultrasonic oscillator for 30 min at room temperature, and then dried in a drying oven at 80°C for 30 min. (2) The microchannel nickel plate (151) was vertically immersed in the dopamine reaction solution for 12 hours. The resulting polydopamine-coated substrate was ultrasonically cleaned with deionized water for 30 seconds and then dried with nitrogen before storage. (3) Use a syringe to evenly inject the catalyst slurry into the microchannels treated in step (2), dry the coated microchannel nickel plate at room temperature for 12 hours, and then put it in a drying oven at 180°C for 3 hours to obtain the product.

6. The integrated marine propulsion system with microreactor coupled fuel cell according to claim 5, wherein: The dopamine reaction solution in step (2) is prepared by the following method: Prepare a dopamine reaction solution with a concentration of 2 mg / mL and pH=8.5 using dopamine, Tris, and deionized water.

7. The integrated marine propulsion system with microreactor coupled fuel cell according to claim 5, wherein: The catalyst slurry in step (3) is prepared by the following method: The catalyst and polyvinyl alcohol were mixed at a mass ratio of 1:4 to prepare a 5% mass fraction solution. The solution was treated with an ultrasonic oscillator at room temperature for 30 min, and then stirred at room temperature for 6 h to obtain a catalyst slurry for later use.

8. The integrated marine propulsion system with microreactor coupled fuel cell according to claim 1, wherein: The microchannel nickel plate (151) contains a mixed solution of methanol and seawater containing chloride ions.

Images