Lightweight hydrogen fuel cell hydrogen supply system

Abstract

A lightweight hydrogen fuel cell hydrogen supply system relates to the technical field of new energy hydrogen production, and comprises a feed port, a hydrogen outlet and a discharge port which are arranged on a hydrogen production reactor, a water inlet pipeline is arranged at the top of the hydrogen production reactor, an electric control valve is arranged on the water inlet pipeline, and a plurality of nozzles communicated with the water inlet pipeline are arranged on the upper side in the hydrogen production reactor. A material stirrer is arranged in the hydrogen production reactor in a penetrating manner; the electric adjusting valve is coupled with a control system, the control system controls the adding amount of hot water by controlling the opening degree and the opening time of the electric adjusting valve, and when the mass ratio of the catalyst added into the feeding port to the ammonia borane is 1: 2, the mass ratio of the adding amount of the ammonia borane to the adding amount of the hot water is 1: X, and the value of X is 0.8-2.5, the control system controls the adding amount of the hot water. The ammonia borane, the catalyst and the hot water always form a semi-fluid state between a solid state and a liquid state. According to the invention, the addition amount of water in the reaction system is reduced, the weight of the hydrogen production system is effectively reduced, and the hydrogen production amount per unit weight of the hydrogen production system is increased.

Description

Technical Field

[0001] This invention relates to the field of new energy hydrogen production technology, and mainly to a lightweight hydrogen fuel cell hydrogen supply system. Background Technology

[0002] Ammonia borane (NH3BH3) is characterized by its chemical stability, solid state at room temperature and pressure, high hydrogen content (19.6 wt%), and moderate hydrogen release kinetics. Under standard conditions, ammonia borane has a melting point of 104℃ and a density of 0.780 g / cm³. 3 Ammonia borane aqueous solution can undergo hydrolysis under normal temperature and pressure with the aid of a catalyst to release high-purity H2. The catalytic hydrolysis of ammonia borane to produce hydrogen is significantly positively correlated with the reaction temperature; therefore, increasing the reaction temperature is crucial to improving the efficiency of hydrogen production from ammonia borane hydrolysis. Traditional ammonia borane hydrogen production technology involves the hydrolysis of an aqueous solution of ammonia borane with a catalyst to produce hydrogen. However, the amount of water participating in the reaction is far greater than the actual amount of water added. This results in an excess of water relative to the hydrogen production requirement, increasing the weight of the entire hydrogen production system and reducing the hydrogen production per unit weight. Summary of the Invention

[0003] In view of the aforementioned technical problems, the purpose of this invention is to propose a lightweight hydrogen fuel cell hydrogen supply system.

[0004] The objective of this invention is achieved through the following technical solution. A lightweight hydrogen fuel cell hydrogen supply system according to this invention includes a hydrogen production reactor, a feed port and a hydrogen outlet located on the top side wall of the hydrogen production reactor, and a discharge port located at the bottom of the hydrogen production reactor. The top of the hydrogen production reactor is also equipped with a water inlet pipe connected to the hot water generated during the operation of the hydrogen fuel cell. An electric regulating valve is installed on the water inlet pipe. Multiple rows of nozzles are distributed on the upper side of the interior of the hydrogen production reactor, and all nozzles are connected to the water inlet pipe. A material stirrer is installed inside the hydrogen production reactor, and a drive motor is installed outside the stirrer, with the output shaft of the drive motor connected to the rotating shaft of the material stirrer. The electric regulating valve is coupled to a control system, which controls the amount of hot water added by controlling the opening degree and opening time of the electric regulating valve. When the mass ratio of the catalyst to ammonia borane added to the hydrogen production reactor is 1:2, and the mass ratio of ammonia borane to hot water is 1:X, with X ranging from 0.8 to 2.5, the ammonia borane, catalyst, and hot water always form a semi-fluid state between solid and liquid.

[0005] Furthermore, several stirring blades are connected to the rotating shaft. The two stirring blades at the outermost end of the rotating shaft are arranged symmetrically, and the remaining stirring blades between the two outermost stirring blades are all arranged perpendicular to the rotating shaft.

[0006] Furthermore, each stirring blade includes multiple sub-blades distributed circumferentially. Each sub-blade has a U-shaped opening at its top far from the central axis. The sub-blade between the U-shaped opening and the central axis has a through hole. The two sub-blades located on both sides of the through hole are elliptical arcs and are symmetrically arranged.

[0007] Furthermore, the discharge port is connected to the top inlet of the catalyst recovery tank via a liquid shut-off valve. The bottom of the catalyst recovery tank is provided with a channel that connects to the top inlet of the waste liquid recovery tank, and the channel is provided with a microporous filter membrane that the catalyst cannot pass through.

[0008] Furthermore, an ammonia removal device and a drying device are sequentially installed along the hydrogen flow direction on the pipeline connected to the hydrogen outlet.

[0009] Based on the aforementioned technical solution, the present invention has the following beneficial effects: (1) The present invention controls the opening degree and opening time of the electric regulating valve through the control system to control the amount of hot water added, so that the ammonia borane, catalyst and hot water in the hydrogen production reactor are always in a semi-fluid state. This not only reduces the amount of water added in the reaction system, but also effectively reduces the weight of the hydrogen production system and increases the hydrogen production per unit weight of the hydrogen production system, which is conducive to its application in mobile hydrogen fuel power devices (hydrogen fuel electric vehicles, hydrogen fuel electric bicycles, hydrogen fuel electric aircraft, etc.); (2) The system can make full use of the hot water resources in the operation of the hydrogen fuel cell, without the need for external additional water supply for the reaction, thus avoiding the waste of hot water resources. Moreover, the pure hydrogen produced in the hydrogen production reactor can be used by the hydrogen fuel cell, which is conducive to improving the integration of the system.

[0010] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0011] Figure 1 This is a schematic diagram illustrating the working principle of a lightweight hydrogen fuel cell hydrogen supply system according to the present invention.

[0012] Figure 2 This is a schematic diagram of the structure of the stirring blades on the material stirrer in a lightweight hydrogen fuel cell hydrogen supply system of the present invention.

[0013] Figure 3 This is a schematic diagram of the arrangement of several nozzles on the upper side inside the hydrogen production reactor in a lightweight hydrogen fuel cell hydrogen supply system of the present invention.

[0014] Figure 4This is a graph showing the catalytic hydrogen production performance of ammonia borane in solution and semi-fluid states. The horizontal axis represents the reaction time, and the vertical axis represents the molar ratio of hydrogen produced to the reactant ammonia borane.

[0015] Attached reference numerals: 101, Waste liquid recovery tank; 102, Microporous filter membrane; 103, Catalyst recovery tank; 104, Liquid shut-off valve; 105, Hydrogen production reactor; 106, Drive motor; 107, Material agitator; 1071, Agitator blade; 1071-1, U-shaped opening; 1071-2, Through hole; 108, Nozzle; 109, Electric regulating valve; 110, Ammonia removal device; 111, Drying device; 112, Feed port; 113, Water inlet pipe; 114, Hydrogen outlet; 115, Discharge port. Detailed Implementation

[0016] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings: Please see Figure 1 This invention discloses a lightweight hydrogen fuel cell hydrogen supply system, comprising a hydrogen production reactor 105, an ammonia removal device 110, a drying device 111, a catalyst recovery tank 103, and a waste liquid recovery tank 101. A feed port 112 is provided on the side wall of the top of the hydrogen production reactor. Ammonia borane and the synthesis catalyst RuNi@g-C3N4 are uniformly mixed in a certain proportion and fed into the hydrogen production reactor through the feed port. The top of the hydrogen production reactor is also provided with a water inlet pipe 113 connected to the hot water generated during the operation of the hydrogen fuel cell. An electric regulating valve 109 is provided on the water inlet pipe. Multiple rows of nozzles 108 are distributed on the upper side of the interior of the hydrogen production reactor (see [reference]). Figure 3 The nozzles on adjacent rows are staggered to ensure uniform water spray volume per unit area. All nozzles are connected to the water inlet pipe. The hot water generated during the operation of the hydrogen fuel cell is sprayed into the hydrogen production reactor through the water inlet pipe and the nozzles. The electric regulating valve is coupled to a control system. The control system determines the amount of water (hot water generated during the operation of the hydrogen fuel cell) to be added based on the amount of ammonia borane added. The control system controls the amount of hot water added by controlling the opening degree and opening time of the electric regulating valve. The hot water is sprayed quantitatively and uniformly onto the surface of the catalyst and ammonia borane mixture so that ammonia borane, catalyst and water always form a semi-fluid state between solid and liquid. The mass ratio of catalyst to ammonia borane in the semi-fluid state is 1:2, and the mass ratio of ammonia borane to added water is 1:X, where X is 0.8 to 2.5.

[0017] Please refer to the following: Figure 2A material agitator 107 is installed inside the hydrogen production reactor along the left-right direction. A drive motor 106 is installed outside the agitator, and the output shaft of the drive motor is connected to the rotating shaft of the material agitator. Several stirring blades 1071 are connected to the rotating shaft (in this embodiment, the stirring blades are connected to the rotating shaft by welding or riveting). The stirring blade located at the leftmost end of the rotating shaft has an angle of 45° with the rotating shaft, and the stirring blade located at the rightmost end of the rotating shaft has an angle of 135° with the rotating shaft, so that the two stirring blades are symmetrically arranged. The remaining stirring blades located between the two aforementioned stirring blades are all perpendicular to the rotating shaft. The number of stirring blades at this position can be set according to actual needs to ensure that the stirring blades can fully stir the material over the maximum range. Furthermore, each stirring blade 1071 includes multiple sub-blades distributed circumferentially. Each sub-blade has a U-shaped opening 1071-1 at its top far from the central axis. The sub-blade between the U-shaped groove and the central axis has a through hole 1071-2. The two sub-blades on both sides of the through hole are elliptical arcs and symmetrically arranged. This not only helps to stir the semi-fluidized reaction material evenly, but also reduces the overall weight of the stirring blade, thereby reducing the energy consumption of the stirring blade.

[0018] The hydrogen production reactor has a discharge port 115 at the bottom, which is connected to the top inlet of the catalyst recovery tank 103 through a liquid shut-off valve 104. The bottom of the catalyst recovery tank has a channel connected to the top inlet of the waste liquid recovery tank 101, and a microporous filter membrane 102 is provided on the channel. In this embodiment, the pore size of the microporous filter membrane can be selected from 0.1um to 100um depending on the size of the catalyst particles, and the material can be polytetrafluoroethylene (PTFE) or polypropylene (PP), etc. The catalyst in the by-product solution cannot pass through the microporous filter membrane and is thus left in the catalyst recovery tank. The by-product solution without catalyst enters the waste liquid recovery tank.

[0019] The side wall at the top of the hydrogen production reactor is also provided with a hydrogen outlet 114. An ammonia removal device 110 and a drying device 111 are sequentially arranged along the hydrogen flow direction on the pipeline connected to the hydrogen outlet. The acid solution used in the ammonia removal device is one or a mixture of hydrochloric acid solution or sulfuric acid solution. The hydrogen outlet of the drying device 111 is connected to the hydrogen storage tank (not shown in the figure) through a pipeline. The desiccant in the drying device is one or a mixture of calcium chloride or calcium sulfate.

[0020] This invention discloses a lightweight hydrogen fuel cell hydrogen supply system. The catalyst active component for catalyzing ammonia borane is RuNi, and the support is g-C3N4. The g-C3N4 support has the characteristics of high specific surface area and low density. Its high specific surface area ensures that the metal active component can be fully and uniformly loaded, while the low density of the g-C3N4 support reduces the weight of the RuNi@g-C3N4 catalyst, which is beneficial to the uniform mixing of the catalyst and ammonia borane. The active metal loading of the catalyst in this invention is between 3% and 12%, wherein the mass ratio of Ru to Ni is 3:2. The method of loading active metal alloy nanoclusters onto the g-C3N4 support is a liquid-phase reduction method. Utilizing the synergistic effect of heterometallic Ru and Ni, the synthesized catalyst RuNi@g-C3N4 achieves ammonia borane catalytic activity comparable to that of pure noble metal Ru@g-C3N4 catalyst, thus reducing the catalyst usage cost while ensuring the hydrogen production rate of ammonia borane. In the reactants, the mass ratio of catalyst to ammonia borane is 1:2; the mass ratio of ammonia borane to added water is 1:X, and X ranges from 0.8 to 2.5.

[0021] The specific preparation process is as follows: a certain amount of melamine (C3H6N6) is placed in a grinding mortar and ground evenly, then poured into a crucible, sealed with aluminum foil, and placed in a muffle furnace for heating to 550°C and kept at that temperature for 5 hours. After the reaction is complete and the mixture is allowed to cool naturally to room temperature, the pale yellow product in the crucible is removed and thoroughly ground into powder. The resulting pale yellow powder is g-C3N4. A measured amount of ruthenium chloride (RuCl3) and nickel nitrate (Ni(NO3)2) are weighed out and mixed evenly. The mixture is then dissolved in an appropriate amount of anhydrous ethanol to form a mixed salt solution. The g-C3N4 sample is then added to the mixed salt solution and dispersed by ultrasonication for 30 min and magnetically stirred for 50 min to ensure uniform mixing, resulting in mixed solution A. Fresh 0.2 mol / L sodium borohydride solution is added dropwise to the 0°C mixed solution A until the amount of sodium borohydride reducing agent added is in excess relative to the metal salts (RuCl3, Ni(NO3)2) to be reduced. The stirrer is continuously used during the reaction. After the addition is complete, stirring is continued for 2 h. The solid material after filtration is placed in a vacuum drying oven for drying. The resulting powder is calcined at 500°C for 5 h under vacuum conditions. The solid is then removed and ground into powder, which is the catalyst RuNi@g-C3N4.

[0022] The working principle of the lightweight hydrogen fuel cell hydrogen supply system of this invention is as follows: First, catalyst RuNi@g-C3N4 and ammonia borane are added to the hydrogen production reactor through the feed inlet, with the mass ratio of catalyst to ammonia borane being 1:2. The control system controls the opening degree and opening time of the electric regulating valve to control the amount of hot water added. The hot water is sprayed into the hydrogen production reactor through several nozzles, ensuring that the mass ratio of ammonia borane to added water is 1:X, where X is 0.8 to 2.5. After stirring evenly, the ammonia borane, catalyst, and water within this ratio range are in a semi-fluid state between solid and liquid. When the hydrogen production reactor... When the solid reactants in the reactor accumulate to a certain amount: first, water is added to the hydrogen production reactor to form a solution of byproducts and catalyst. The liquid shut-off valve at the bottom is opened, and the solution formed by byproducts and catalyst enters the catalyst recovery tank through the discharge port. The microporous filter membrane at the bottom of the catalyst recovery tank retains the catalyst in the catalyst recovery tank, and the byproduct solution enters the waste liquid recovery tank. The hydrogen produced in the hydrogen production reactor enters the ammonia removal device and the drying device in sequence through the hydrogen outlet to remove ammonia impurities and water vapor mixed in the gas. The purified hydrogen after treatment can provide pure hydrogen for hydrogen fuel cells.

[0023] Example 1: Weigh 50g of ammonia borane powder and 25g of catalyst RuNi@g-C3N4 powder and put them into the hydrogen production reactor. Start the material stirrer to mix them evenly. The control system starts the electric regulating valve to spray the hot water generated during the operation of the hydrogen fuel cell into the reactor through the nozzle array at the top of the reactor. The hot water is then fully mixed with the ammonia borane and catalyst. The water inlet is controlled by adjusting the opening degree and opening time of the electric regulating valve. When the water inlet reaches 40g, the control system closes the electric regulating valve and the water inlet stops. At this time, the reaction slurry is in a semi-fluid state.

[0024] Example 2: Weigh 50g of ammonia borane powder and 25g of catalyst RuNi@g-C3N4 powder and put them into the hydrogen production reactor. Start the material stirrer to mix them evenly. The control system starts the electric regulating valve to spray the hot water generated during the operation of the hydrogen fuel cell into the reactor through the nozzle array at the top of the hydrogen production reactor. The hot water is then fully mixed with the ammonia borane and catalyst. The water inlet is controlled by adjusting the opening degree and opening time of the electric regulating valve. When the water inlet reaches 50g, the control system closes the electric regulating valve and the water inlet stops. At this time, the reaction slurry is in a semi-fluid state.

[0025] Example 3: Weigh 50g of ammonia borane powder and 25g of catalyst RuNi@g-C3N4 powder and place them into the hydrogen production reactor. Start the material stirrer to mix them evenly. Start the electric regulating valve to spray the hot water generated during the operation of the hydrogen fuel cell into the reactor through the nozzle array at the top of the hydrogen production reactor and mix it thoroughly with the ammonia borane and catalyst. Control the water inflow by adjusting the opening degree and opening time of the electric regulating valve. When the water inflow reaches 536g, the control system closes the electric regulating valve and the water inflow stops. At this time, the reaction liquid is completely liquid and the concentration of ammonia borane is about 3mol / L.

[0026] Please see Figure 4 The catalyst used is Ru 0.6 Ni 0.4 @g-C3N4, with a total metal loading of 8% and a Ru:Ni mass ratio of 3:2; the mass ratio of ammonia borane to catalyst is 2:1. As shown in the figure, ammonia borane can completely undergo hydrolysis to produce hydrogen in solution (ammonia borane concentration of 3 mol / L). In the semi-fluid state (ammonia borane to water mass ratio of 1:1), the hydrogen production rate of ammonia borane and the degree of completion of the hydrolysis to produce hydrogen are both reduced. This is related to the increased viscosity in the semi-fluid state and the reduced contact between the catalyst, ammonia borane, and hot water. However, the use of hot water in the semi-fluid state reduces the use of hot water in the reaction system, avoids the waste of hot water resources, and effectively reduces the weight of the hydrogen production system, thereby increasing the hydrogen production per unit weight.

[0027] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention, as long as they do not depart from the design and scope of the technical solutions of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. A lightweight hydrogen fuel cell hydrogen supply system, comprising a hydrogen production reactor (105), a feed port (112) and a hydrogen outlet (114) disposed on the top side wall of the hydrogen production reactor, and a discharge port (115) disposed at the bottom of the hydrogen production reactor, characterized in that: The top of the hydrogen production reactor is also equipped with an inlet pipe (113) that is connected to the hot water generated during the operation of the hydrogen fuel cell. An electric regulating valve (109) is provided on the inlet pipe. Several nozzles (108) are arranged in multiple rows on the upper side of the interior of the hydrogen production reactor, and all the nozzles are connected to the inlet pipe. A material agitator (107) is installed inside the hydrogen production reactor, and a drive motor (106) is provided outside the agitator. The output shaft of the drive motor is connected to the rotating shaft of the material agitator. The electric regulating valve is coupled to a control system. The control system controls the amount of hot water added by controlling the opening degree and opening time of the electric regulating valve. When the mass ratio of the catalyst and ammonia borane added to the hydrogen production reactor is 1:2, and the mass ratio of ammonia borane to hot water added is 1:X with X ranging from 0.8 to 2.5, the ammonia borane, catalyst and hot water always form a semi-fluid state between solid and liquid.

2. The lightweight hydrogen fuel cell hydrogen supply system according to claim 1, characterized in that: Several stirring blades (107) are connected to the rotating shaft. The two stirring blades at the outermost end of the rotating shaft are symmetrically arranged, and the remaining stirring blades between the two outermost stirring blades are all arranged perpendicular to the rotating shaft.

3. The lightweight hydrogen fuel cell hydrogen supply system according to claim 2, characterized in that: Each stirring blade includes multiple sub-blades distributed circumferentially. Each sub-blade has a U-shaped opening (1071-1) at its top far from the central axis. The sub-blade between the U-shaped opening and the central axis has a through hole (1071-2). The two sub-blades located on both sides of the through hole are elliptical arcs and are symmetrically arranged.

4. The lightweight hydrogen fuel cell hydrogen supply system according to claim 1, characterized in that: The discharge port is connected to the top inlet of the catalyst recovery tank (103) via a liquid shut-off valve (104). The bottom of the catalyst recovery tank (103) is provided with a channel that is connected to the top inlet of the waste liquid recovery tank (101), and the channel is provided with a microporous filter membrane (102) that the catalyst cannot pass through.

5. A lightweight hydrogen fuel cell hydrogen supply system according to claim 1, characterized in that: An ammonia removal device (110) and a drying device (111) are sequentially installed along the hydrogen flow direction on the pipeline connected to the hydrogen outlet.

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