Integrated device and method for hydrogen production and use based on trickle bed continuous dehydrogenation reactor

Abstract

The present invention discloses an integrated hydrogen production and use device and method based on a trickle bed continuous dehydrogenation reactor. The device consists of a trickle bed continuous dehydrogenation reactor, a proton exchange membrane fuel cell and accessories, and realizes the coupling of a gas-solid-liquid heterogeneous continuous dehydrogenation process and an online electric energy conversion process of the product hydrogen. In the continuous dehydrogenation process, the liquid organic hydrogen storage material dodecahydroethylcarbazole is used as the dehydrogenation raw material, the ionic liquid is used as the solvent, and the synthesized Pt / S-Ti3C2T x It is a dehydrogenation catalyst. The hydrogen produced by the present invention is high-purity green hydrogen, which is directly used in fuel cells after being purified by pressure swing adsorption. The entire process is controlled by a temperature controller, which precisely controls each stream and reaction temperature, completing the catalytic reaction while maximizing energy utilization. The tail end of the continuous dehydrogenation reactor is connected to a gas chromatograph, and the corresponding reaction parameters are adjusted by online analysis of the reaction products to maximize the conversion rate. The dehydrogenation capacity of the continuous dehydrogenation reactor in the present invention can reach 5.5wt%, and the energy conversion efficiency of the proton exchange membrane fuel cell can reach 60%.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic liquid hydrogen storage, and specifically relates to a hydrogen production and hydrogen use integrated device based on a trickle bed continuous dehydrogenation reactor and a Pt / S-Ti3C2T3O3O4O4O5 ... x Catalyst and preparation method thereof. Background Art

[0002] In recent years, energy shortages and environmental pollution have become two major issues that cannot be ignored by countries around the world. Experts and scholars have therefore been constantly trying to find a clean, pollution-free, and efficient energy source to replace the high proportion of traditional fossil fuels in the energy structure. Hydrogen energy, as a secondary green energy source, is considered to be the most promising energy alternative due to its pollution-free, high calorific value, high reserves, and high efficiency, and has received widespread attention from all walks of life. However, the industrial utilization of hydrogen energy still faces many technical difficulties, especially in the storage and transportation of hydrogen energy. For example: high-pressure gaseous hydrogen storage technology has a low hydrogen storage capacity, requires high hydrogen bottle technology, and may pose a safety hazard; carbonaceous material hydrogen storage technology is expensive, and carbon nanotechnology is immature; metal alloy hydrogen storage technology is prone to pulverization and is inconvenient to transport.

[0003] Researchers have discovered that reversible cycles of hydrogenation and dehydrogenation of unsaturated organic compounds, such as alkenes, alkynes, and aromatic hydrocarbons, can provide an effective reversible hydrogen storage method. This hydrogen storage method, known as liquid organic hydrogen storage technology, combines advantages in hydrogen storage density and ease of storage and transportation. It not only significantly reduces energy consumption and commercial costs for hydrogen storage, but also significantly improves safety during storage and transportation. The hydrogen storage materials used in this hydrogen storage technology are recyclable, and the storage process is pollution-free, making it an environmentally friendly technology. Liquid organic hydrogen storage systems are relatively large and diverse. The most widely reported is the aromatic hydrocarbon dodecahydroethylcarbazole, which was the first proposed liquid organic hydrogen storage material capable of reversible hydrogenation and dehydrogenation below 473 K. Ethylcarbazole is a colorless, flaky crystal at room temperature and pressure. It undergoes rapid hydrogenation at temperatures between 403 and 423 K and under hydrogen pressure, and rapid dehydrogenation at 453 K. Its theoretical hydrogen storage capacity is 5.79 wt%, meeting the US Department of Energy's 5.5 wt% hydrogen storage requirement.

[0004] Currently, the use of dodecahydroethylcarbazole as a hydrogen storage material remains confined to laboratory and small-scale applications. Efficient dehydrogenation catalysts and continuous dehydrogenation equipment are bottlenecks to its large-scale development and application. Commercial dehydrogenation catalysts, typically platinum- and palladium-based, such as Pt / Al2O3, Pt / C, and Pd / Al2O3, struggle to achieve efficient dehydrogenation at relatively low temperatures. Furthermore, the high amount of precious metals required restricts their commercial use. Currently, the dehydrogenation cycle of ethylcarbazole systems is primarily carried out in batch reactors, resulting in low production efficiency and difficulty in achieving continuous hydrogen production, significantly limiting the development of hydrogen energy. To further commercialize organic liquid hydrogen storage materials, the design and synthesis of a low-load catalyst that can enhance the dehydrogenation efficiency of dodecahydroethylcarbazole at relatively low temperatures, as well as the design of continuous dehydrogenation equipment that is highly compatible with the ethylcarbazole system, are essential.

[0005] Ti3C2T x Ti3C2T is a two-dimensional inorganic material that has been widely used in the field of electrochemistry since its discovery due to its excellent conductivity. However, its use as a carrier in the dehydrogenation reaction of dodecahydroethylcarbazole has not been studied. Because of its large specific surface area, it will provide sufficient loading sites as a carrier. x It can be etched from Ti3AlC2 by hydrofluoric acid system or hydrofluoric acid + lithium fluoride system. x It represents the terminal groups introduced during the etching process, such as -OH, -F, etc.

[0006] Continuous reactors are widely used in large-scale industrial processes due to their stable quality, easy operation and control, and high production efficiency. The trickle bed continuous reactor is a gas-liquid-solid three-phase catalytic continuous reactor with unparalleled advantages in large-scale heterogeneous catalytic processes. For example, during the reaction, the gas and liquid flows approach plug flow, resulting in high conversion rates.

[0007] Currently, there are two key factors hindering the progress of this hydrogen storage technology: one is how to design an efficient dehydrogenation catalyst with low precious metal loading that can improve the selectivity and reaction rate of dodecahydroethylcarbazole at lower temperatures; the other is how to design a continuous dehydrogenation equipment to improve the hydrogen production efficiency of the entire hydrogen storage cycle. Summary of the Invention

[0008] In order to solve the above technical bottlenecks, the purpose of the present invention is to provide an integrated device and method for hydrogen production and use based on a trickle bed continuous dehydrogenation reactor, which solves the problems of the existing technology that it cannot achieve continuous production and the complex process. When used, it can accurately control the reaction temperature and flow.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A hydrogen production and use integrated device based on a trickle bed continuous dehydrogenation reactor, the device comprising: a micro-injection pump 1, a heat exchanger 2, a preheater 4, a reactor 8, a gas-liquid separator 15, a gas chromatograph 18, a PSA pressure swing adsorption machine 21, a proton exchange fuel membrane cell 23 and an air compressor 27; the dehydrogenation raw material is injected by the micro-injection pump 1, the outlet of the micro-injection pump 1 is connected to the cold medium inlet of the heat exchanger 2; the cold medium outlet of the heat exchanger 2 is connected to the inlet of the preheater 4 through a pipeline, and the outlet of the preheater 4 is connected to the inlet of the reactor 8; the gas phase outlet at the upper end of the reactor 8 is connected to the hot medium inlet of the heat exchanger 2 through an upper opening valve 9, and the liquid phase outlet at the lower end of the reactor 8 is connected to the hot medium inlet of the heat exchanger 2 through a lower opening valve 13 It is connected to the inlet of the gas-liquid separator 15; the gas phase outlet at the upper end of the gas-liquid separator 15 is connected to the heat medium inlet of the heat exchanger 2 through the upper three-way valve 14, and the liquid phase outlet at the lower end of the gas-liquid separator 15 is connected to the gas chromatograph 18 through the lower three-way valve 17. The product after the dehydrogenation reaction is extracted from the other outlet of the lower three-way valve 17 for subsequent treatment; the heat medium outlet of the heat exchanger 2 is connected to the inlet of the PSA pressure swing adsorption machine 21 through a pipeline, and the outlet of the PSA pressure swing adsorption machine 21 is connected to the inlet of the proton exchange membrane fuel cell 23. Air is injected by the air compressor 27, and the outlet of the air compressor 27 is connected to the inlet of the proton exchange membrane fuel cell 23. The product water flows out through the outlet of the proton exchange fuel cell 23.

[0011] The preheater 4 is composed of a heating tube 3, a heat-insulating outer layer 30 arranged outside the heating tube 3, and a thermocouple thermometer 5 for measuring the temperature of the preheater.

[0012] The system further comprises a thermocouple thermometer 6 for measuring the insulation temperature, which is arranged between the preheater 4 and the reactor 8 and is used for measuring the insulation temperature.

[0013] The reactor 8 consists of a reaction tube 11, a demister 7 and a liquid distributor 28 placed at the top of the reaction tube 11, a catalyst layer 29 placed in the reaction tube 11, and a thermocouple thermometer 10 for measuring the reaction temperature and a thermocouple thermometer 12 for measuring the reactor temperature.

[0014] The gas-liquid separator 15 is further provided with a thermocouple thermometer 16 for measuring the temperature of the gas-liquid separator.

[0015] The proton exchange fuel cell 23 is composed of a diffusion layer 26 , a proton exchange membrane 25 and a catalyst layer 24 , wherein the catalyst layer 24 is located at the center of the cell, and the proton exchange membrane 25 is located on both sides of the catalyst layer 24 to separate the catalyst layer 24 from the diffusion layer 26 .

[0016] An integrated method for hydrogen production and utilization based on a trickle bed continuous dehydrogenation reactor, using the device, comprises the following steps:

[0017] S1, the dehydrogenation feedstock is added to the preheater 4 at a certain volume flow rate by the micro-injection pump 1 for fluid preheating treatment. After preheating, it enters the reactor 8 from the preheater 4 and is evenly distributed by the liquid distributor 28. It flows from top to bottom in the reaction tube 11 until it contacts the catalyst layer 29, and a dehydrogenation reaction occurs;

[0018] S2, the reaction product consists of ethylcarbazole organic matter and hydrogen, the hydrogen flows from bottom to top in the reaction tube 11, passes through the demister 7 to remove the entrained liquid, and flows out of the reactor 8 through the pipeline at the upper switch valve 9 to the heat exchanger 2;

[0019] S3, the ethylcarbazole organic mixture after dehydrogenation flows from top to bottom in the reaction tube 11, flows out of the reactor 8 through the pipeline at the lower opening switch valve 13 to the gas-liquid separator 15;

[0020] S4. After separation, hydrogen flows out from the upper outlet of the gas-liquid separator 15 and is controlled by the upper three-way valve 14 to flow into the heat exchanger 2 or to be exhausted. Liquid flows out from the lower outlet of the gas-liquid separator 15 and is controlled by the lower three-way valve 17 to be directly collected as a hydrogenation feedstock for the dehydrogenation cycle or directly fed into the gas chromatograph 18 for online component analysis.

[0021] S5. The hydrogen in the product exchanges heat with the initial dehydrogenation feedstock through the heat exchanger 2 to fully utilize the energy. The hydrogen after heat exchange is purified by the PSA pressure swing adsorption machine 21; then the high-purity hydrogen is directly introduced into the negative electrode of the proton exchange membrane fuel cell 23 as fuel; the positive electrode fuel of the proton exchange membrane fuel cell 23 is air input to the positive electrode of the fuel cell by the air compressor 27.

[0022] The volume flow rate of the dehydrogenation feedstock in step S1 ranges from 0.001 μL to 43.349 mL / min.

[0023] In step S1 , the temperatures in the preheater 4 and the reactor 8 are both set to 180° C.; in step S5 , the operating temperature of the proton exchange membrane fuel cell 23 is 80° C.

[0024] The catalyst of the catalyst layer in step S1 is prepared as follows:

[0025] Step 1, Ti3C2T x The specific steps for carrier preparation are as follows:

[0026] 1) Add 1.6 g of LiF and 20 ml of 12 mol / L concentrated hydrochloric acid to a polypropylene beaker, place on a magnetic stirrer and stir for 10 min to fully dissolve the LiF. Then add 1.0 g of MAX (Ti3AlC2) to the beaker to obtain mixture A. To prevent severe heat release, the addition process is carried out in an ice water bath;

[0027] 2) The mixture A was heated to 50° C. with stirring and reacted for 24 h, after which the heating was stopped and the mixture was cooled to room temperature; the cooled mixture was centrifuged, washed three times with dilute hydrochloric acid solution, and then washed with deionized water until the pH was 6-7, and the lower layer of solid was obtained by centrifugation;

[0028] 3) Dry the obtained solid in a vacuum drying oven overnight to obtain multilayer Ti3C2T x carrier.

[0029] Step 2: Pt / S-Ti3C2T x The specific steps for preparing the catalyst are as follows:

[0030] 1) 0.1g multilayer Ti3C2T x The carrier and 0.4 g of PVP (polyvinyl pyrrolidone) were added to a 50 ml beaker, and then 20 ml of deionized water was added and ultrasonicated for 10 min. The mixture was stirred at room temperature for 24 h to obtain a mixture B.

[0031] 2) The mixture B was centrifuged, washed three times with deionized water, and then added with 20 ml of deionized water and centrifuged and stirred to disperse again to obtain PVP / Ti3C2T x Dispersion; add the corresponding mass of potassium chloroplatinate to another beaker according to the platinum loading of 1.0-5.0% by mass, and add 5ml of deionized water to dissolve it, and add the dissolved potassium chloroplatinate dropwise to the PVP / Ti3C2T x The dispersion was stirred for 24 h to obtain a mixture C;

[0032] 3) 0.1 g of sodium borohydride solution was added dropwise to the mixture C and stirred for 6 h. After centrifugation, the mixture was washed with deionized water and anhydrous ethanol. The obtained solid was dried in a vacuum drying oven overnight to obtain Pt / S-Ti3C2T x catalyst.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] The process flow is simple, the device structure is compact, the floor space is small, and the catalyst filler is easy to disassemble and assemble.

[0035] The entire process is carried out under normal pressure, which does not require high pressure resistance of the equipment and reduces equipment costs.

[0036] The temperature in the process is precisely controlled by a temperature controller, and the high-temperature product exchanges heat with the low-temperature raw material, which greatly reduces energy consumption and lowers energy costs.

[0037] The integrated device converts hydrogen storage materials directly into electricity, enabling rapid electricity production and reducing hydrogen transportation costs. The hydrogen produced during the process is high-purity and maintained at the fuel cell operating temperature, reducing additional heat input and costs.

[0038] The liquid product is connected to a gas chromatograph to realize online analysis of the product, and then the process parameters such as catalyst loading and feed rate can be adjusted according to the product conversion rate.

[0039] The process uses ionic liquid as solvent to increase the fluidity of raw materials and reduce the volatility of raw materials; the self-synthesized Pt / S-Ti3C2T x The catalyst is a dehydrogenation catalyst, which greatly enhances the conversion rate and selectivity of the dehydrogenation reaction, and the final dehydrogenation amount reaches more than 5.5wt%. In addition, the catalyst has a small amount of precious metal, good dispersibility and small particle size, which greatly reduces the catalyst cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a process flow diagram of the present invention.

[0041] Figure 2 It is a schematic diagram of the dehydrogenation reaction tube used in the dehydrogenation process of the present invention.

[0042] Figure 3 The Pt / S-Ti3C2T prepared by the present invention x X-ray diffraction pattern of the catalyst.

[0043] Figure 4 The Pt / S-Ti3C2T prepared by the present invention x Pt element peak fitting in the X-ray photoelectron spectrum of the catalyst.

[0044] Figure 5 The Pt / S-Ti3C2T prepared by the present invention x High-definition transmission electron microscopy images of the catalyst showing its macroscopic morphology at 50nm, 20nm and 10nm scales.

[0045] like Figure 1As shown: 1 is a microinjection pump; 2 is a heat exchanger; 3 is a heating tube; 4 is a preheater; 5 is a thermocouple thermometer for measuring the temperature of the preheater; 30 is an outer insulation layer; 6 is a thermocouple thermometer for measuring the insulation temperature; 7 is a defoamer; 8 is a reactor; 9 is an upper on-off valve; 10 is a thermocouple thermometer for measuring the reaction temperature; 11 is a reaction tube; 12 is a thermocouple thermometer for measuring the temperature of the reactor; 13 is a lower on-off valve; 14 is an upper three-way valve; 15 is a gas-liquid separator; 16 is a thermocouple thermometer for measuring the temperature of the gas-liquid separator; 17 is a three-way valve at the lower end; 18 is a gas chromatograph; 19 is a thermocouple thermometer for measuring the inlet temperature; 20 is a thermocouple thermometer for measuring the outlet temperature; 21 is a PSA pressure swing adsorption machine; 22 is a thermocouple thermometer for measuring the hydrogen temperature; 23 is a proton exchange membrane fuel cell; 24 is a catalyst layer; 25 is a proton exchange membrane; 26 is a diffusion layer; and 27 is an air compressor.

[0046] like Figure 2 As shown: 7 is a demister; 28 is a liquid distributor; 29 is a catalyst layer. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] like Figure 1 and Figure 2 As shown, the prepared Pt / S-Ti3C2T x The catalyst is filled in the reaction tube 11 with a filling volume of 1 to 5 cm. Dodecahydroethylcarbazole is dissolved in an ionic liquid and used as the raw material for the entire dehydrogenation process. This not only solves the problem of insufficient fluidity of dodecahydroethylcarbazole, but also reduces its volatilization, thereby reducing the cost caused by raw material loss.

[0049] First, the dehydrogenation raw material is added to the preheater 4 by a micro-injection pump 1 at a certain volume flow rate for fluid preheating treatment. The volume flow rate range can be: 0.001 μL-43.349 mL / min. The fluid is heated in the heating tube 3, and the heating temperature is regulated by a temperature controller with a programmed temperature system, which includes two digital thermocouple thermometers for temperature monitoring, one for monitoring the set temperature and the other for monitoring the real-time temperature. In the present invention, the temperature is set to 180°C.

[0050] After preheating 4, the raw materials enter the reactor 8 from the preheater 4. Liquid distributor 28 evenly distributes the stream, allowing it to flow from top to bottom in the reaction tube 11 until it contacts the catalyst, causing a dehydrogenation reaction. The temperature is set and maintained at 180°C during the reaction. The reaction products consist of ethylcarbazole organic compounds and hydrogen. The hydrogen flows from bottom to top in the reaction tube 11, passes through a demister 7 to remove entrained liquid, and then exits the reactor 8 through a pipe at the upper on-off valve 9. The dehydrogenated ethylcarbazole organic mixture flows from top to bottom in the reaction tube 11, exiting the reactor 8 through a pipe at the lower on-off valve 13.

[0051] The resulting ethylcarbazole organic mixture flows through the lower on-off valve 13 into the gas-liquid separator 15, where it undergoes gas-liquid separation. The liquid comprises a mixture of various ethylcarbazoles, including dodecahydroethylcarbazole, octahydroethylcarbazole, tetrahydroethylcarbazole, and ethylcarbazole, while the gas comprises hydrogen. After separation, the hydrogen flows out of the upper outlet of the gas-liquid separator and, controlled by the upper three-way valve 14, can be either combined with the hydrogen or evacuated. The liquid flows out of the lower outlet of the gas-liquid separator and, controlled by the lower three-way valve 17, can be directly collected as hydrogenation feedstock for the hydrogenation and dehydrogenation cycles or fed directly to a chromatograph for online component analysis.

[0052] The hydrogen produced previously is combined through the pipeline and then passes through the heat exchanger 2 to exchange heat with the initial dehydrogenation raw materials to fully utilize the energy. Thermocouple digital thermometers are installed before and after the heat exchanger 2 to monitor the temperature, and the hydrogen flow rate is regulated by the outlet temperature to keep the outlet hydrogen temperature at 80°C. The hydrogen after heat exchange is purified by the PSA pressure swing adsorption machine 21 to obtain hydrogen with higher purity, which can reach: ≥99.9995%. The high-purity hydrogen is then directly introduced into the negative electrode of the proton exchange membrane fuel cell 23 as fuel. The positive electrode fuel of the fuel cell is air, which is input to the positive electrode of the fuel cell by the air compressor.

[0053] The pipelines used in the process are kept insulated throughout the entire process to reduce energy loss during pipeline transportation.

[0054] Example 1:

[0055] In this embodiment, an integrated hydrogen production and use device based on a trickle bed continuous dehydrogenation reactor is used. The equipment and models used are as follows: the micro-injection pump 1 model is LSP01-3A; the preheater 4 is a ZC-ST-30KW-B electromagnetic heater; the K-type thermocouple model is DT135K; the demister 7 model is HG / T21618-1998; the liquid distributor 28 is a customized polypropylene (PP) material distributor with a diameter of 6 mm; the perfluoroproton exchange membrane model is N-117 and the thickness is 183 microns; the diffusion layer uses a commercial gas diffusion layer H14C9; the PSA pressure swing adsorption machine model used is SP; the air compressor 27 model is XDwj-60; the switch valve model specification is: 316L, 3mm connector; the three-way valve model specification is: 316L, 3mm connector; the connecting pipe diameter is 3 mm; and the ionic liquid iodide 1,3-dimethylimidazole is used as the solvent for the raw material dodecahydroethylcarbazole.

[0056] The preparation process of the dehydrogenation catalyst is as follows:

[0057] Step 1, Ti3C2T x The specific steps for carrier preparation are as follows: 1) Add 1.6g LiF and 20ml concentrated hydrochloric acid (12M) to a polypropylene beaker, place it on a magnetic stirrer and stir for 10 minutes to fully dissolve the LiF, then add 1.0g of MAX (Ti3AlC2) to the beaker. To prevent violent exotherm, the addition process is carried out in an ice water bath. 2) Heat the above mixture to 50°C while stirring, react for 24 hours, then stop heating and cool to room temperature. Centrifuge the cooled mixture, wash it 3 times with dilute hydrochloric acid solution, then wash it with deionized water to a pH of 6, and centrifuge to obtain the lower layer of solid. 3) Dry the obtained solid in a vacuum drying oven overnight to obtain a multilayer Ti3C2T x carrier.

[0058] Step 2: Pt / S-Ti3C2T x The catalyst was prepared by the following steps: 1) 0.1 g of multilayer Ti3C2T x The carrier and 0.4g PVP (polyvinyl pyrrolidone) were added to a 50ml beaker, and then 20ml deionized water was added and ultrasonicated for 10min, and stirred at room temperature for 24h. 2) The above mixture was centrifuged, washed three times with deionized water, and then added with 20ml deionized water and centrifuged and stirred to disperse again to obtain PVP / Ti3C2T x Dispersion. Add the corresponding mass of potassium chloroplatinate to another beaker according to the platinum loading of 3% by mass, and add 5ml of deionized water to dissolve it. Add the dissolved potassium chloroplatinate dropwise to the PVP / Ti3C2T x3) Add 0.1 g of sodium borohydride solution dropwise to the above mixture and stir for 6 hours. After centrifugation, wash with deionized water and anhydrous ethanol. Dry the obtained solid in a vacuum drying oven overnight to obtain Pt / S-Ti3C2T with a loading of 3%. x catalyst.

[0059] In this Example 1, a microsyringe pump was used to add the raw material dodecahydroethylcarbazole at a rate of 1.5 ml / min. The catalyst packing height was 5 cm. The preheater and reaction tube temperatures were both set to 180°C. The hydrogen flow rate was regulated to maintain the temperature of the hydrogen at the fuel cell at 80°C. The air introduction rate was consistent with the hydrogen flow rate. Gas chromatograph analysis of the product determined a dehydrogenation rate of 5.5 wt %, and the fuel cell conversion efficiency was measured to be 60% (based on the raw material).

[0060] The catalyst prepared in this example was characterized, and its X-ray diffraction pattern was as follows: Figure 3 As shown, the X-ray photoelectron spectrum picture is as follows Figure 4 As shown in Figure 2, it can be seen that the platinum in the catalyst is mainly zero-valent and divalent platinum. Figure 5 As shown, it can be seen that the platinum particles are small and evenly dispersed.

[0061] Example 2:

[0062] In the second embodiment, an integrated hydrogen production and hydrogen use device based on a trickle bed continuous dehydrogenation reactor is used. The equipment and models used are as follows: the micro-injection pump 1 model is LSP01-3A; the preheater 4 is a ZC-ST-30KW-B electromagnetic heater; the K-type thermocouple model is DT135K; the demister 7 model is HG / T21618-1998; the liquid distributor 28 is a customized polypropylene (PP) material distributor with a diameter of 6 mm; the perfluoroproton exchange membrane model is N-117 and the thickness is 183 microns; the diffusion layer adopts a commercial gas diffusion layer H14C9; the PSA pressure swing adsorption machine model used is SP; the air compressor 27 model is XDwj-60; the switch valve model specification is: 316L, 3mm connector; the three-way valve model specification: 316L, 3mm connector; the connecting pipe diameter is 3 mm; and the ionic liquid iodide 1,3-dimethylimidazole is used as the solvent of the raw material dodecahydroethylcarbazole (the same as in the first embodiment).

[0063] The preparation process of the dehydrogenation catalyst is as follows:

[0064] Step 1, Ti3C2T xThe specific steps for carrier preparation are as follows: 1) Add 1.6g LiF and 20ml concentrated hydrochloric acid (12M) to a polypropylene beaker, place it on a magnetic stirrer and stir for 10 minutes to fully dissolve the LiF, then add 1.0g of MAX (Ti3AlC2) to the beaker. To prevent violent exotherm, the addition process is carried out in an ice water bath. 2) Heat the above mixture to 50°C while stirring, react for 24 hours, then stop heating and cool to room temperature. Centrifuge the cooled mixture, wash it 3 times with dilute hydrochloric acid solution, then wash it with deionized water to a pH of 7, and centrifuge to obtain the lower layer of solid. 3) Dry the obtained solid in a vacuum drying oven overnight to obtain a multilayer Ti3C2T x carrier.

[0065] Step 2: Pt / S-Ti3C2T x The catalyst was prepared by the following steps: 1) 0.1 g of multilayer Ti3C2T x The carrier and 0.4g PVP (polyvinyl pyrrolidone) were added to a 50ml beaker, and then 20ml deionized water was added and ultrasonicated for 10min, and stirred at room temperature for 24h. 2) The above mixture was centrifuged, washed three times with deionized water, and then added with 20ml deionized water and centrifuged and stirred to disperse again to obtain PVP / Ti3C2T x Dispersion. Add the corresponding mass of potassium chloroplatinate to another beaker according to the platinum loading of 1% by mass, and add 5ml of deionized water to dissolve it. Add the dissolved potassium chloroplatinate dropwise to the PVP / Ti3C2T x 3) Add 0.1 g of sodium borohydride solution dropwise to the above mixture and stir for 6 hours. After centrifugation, wash with deionized water and anhydrous ethanol. Dry the obtained solid in a vacuum drying oven overnight to obtain Pt / S-Ti3C2T with a loading of 1%. x catalyst.

[0066] In this Example 1, a microsyringe pump was used to add the raw material dodecahydroethylcarbazole at a rate of 1.5 ml / min. The catalyst packing height was 5 cm. The preheater and reaction tube temperatures were both set to 180°C. The hydrogen flow rate was regulated to maintain the temperature of the hydrogen at the fuel cell at 80°C. The air introduction rate was consistent with the hydrogen flow rate. Gas chromatograph analysis of the product determined a dehydrogenation rate of 4.5 wt %, and the fuel cell conversion efficiency was 54% (based on the raw material).

[0067] Example 3:

[0068] The third embodiment is an integrated device for producing and using hydrogen based on a trickle bed continuous dehydrogenation reactor, and the equipment and models used are the same as those in the first embodiment.

[0069] The preparation process of the dehydrogenation catalyst is the same as that in Example 1, and a Pt / S-Ti3C2T3 with a loading of 3% can be obtained. x catalyst.

[0070] In this Example 3, a microsyringe pump was used to add the raw material dodecahydroethylcarbazole at a rate of 2 ml / min. The catalyst packing height was 5 cm. The preheater and reaction tube temperatures were both set to 180°C. The hydrogen flow rate was regulated to maintain the temperature of the hydrogen at the fuel cell at 80°C. The air introduction rate was consistent with the hydrogen flow rate. Gas chromatograph analysis of the product calculated a dehydrogenation rate of 4.3 wt %, and the fuel cell conversion efficiency was measured to be 52% (based on the raw material).

[0071] Example 4:

[0072] The fourth embodiment is an integrated device for producing and using hydrogen based on a trickle bed continuous dehydrogenation reactor, and the equipment and models used are the same as those in the first embodiment.

[0073] The preparation process of the dehydrogenation catalyst is the same as that in Example 1, and a Pt / S-Ti3C2T3 with a loading of 3% can be obtained. x catalyst.

[0074] In this fourth example, a microsyringe pump was used to add the raw material dodecahydroethylcarbazole at a rate of 1 ml / min. The catalyst packing height was 2.5 cm. The preheater and reaction tube temperatures were both set to 180°C. The hydrogen flow rate was regulated to maintain the temperature of the hydrogen at the fuel cell at 80°C. The air flow rate was kept consistent with the hydrogen flow rate. Gas chromatograph analysis of the product determined a dehydrogenation rate of 4.1 wt %, and the fuel cell conversion efficiency was 52% (based on the raw material).

Claims

1. An integrated method for hydrogen production and use based on a trickle bed continuous dehydrogenation reactor, characterized by: The steps include: S1. Dehydrogenation raw materials are added to the preheater (4) at a certain volume flow rate by a micro-injection pump (1) for fluid preheating treatment. After preheating, the fluid enters the reactor (8) from the preheater (4), and the stream is evenly distributed by the liquid distributor (28). The fluid flows from top to bottom in the reaction tube (11) until it contacts the catalyst layer (29), and a dehydrogenation reaction occurs. S2, the reaction product consists of ethylcarbazole organic matter and hydrogen, the hydrogen flows from bottom to top in the reaction tube (11), passes through the demister (7) to remove the entrained liquid, and flows out of the reactor (8) through the pipeline at the upper opening switch valve (9) to the heat exchanger (2); S3, the ethylcarbazole organic mixture after dehydrogenation flows from top to bottom in the reaction tube (11), flows out of the reactor (8) through the pipeline at the lower opening switch valve (13) to the gas-liquid separator (15); S4. After separation, hydrogen flows out from the upper outlet of the gas-liquid separator (15) and is controlled by the upper three-way valve (14) to flow into the heat exchanger (2), or the gas is evacuated; liquid flows out from the lower outlet of the gas-liquid separator (15) and is controlled by the lower three-way valve (17) to be directly collected as a hydrogenation feed for the dehydrogenation cycle, or directly enters the gas chromatograph (18) for online component analysis; S5, the hydrogen in the product is heat exchanged with the initial dehydrogenation raw material through the heat exchanger (2) to fully utilize the energy, and the hydrogen after heat exchange is purified by the PSA pressure swing adsorption machine (21); then the high-purity hydrogen is directly introduced into the negative electrode of the proton exchange membrane fuel cell (23) as fuel; the positive electrode fuel of the proton exchange membrane fuel cell (23) is air input to the positive electrode of the fuel cell by the air compressor (27); The catalyst of the catalyst layer (29) is prepared as follows: Step 1: Preparation of Ti3C2T x carrier; Step 2: Preparation of Pt / S-Ti3C2T x Catalyst, the specific steps are as follows: 1) 0.1g multilayer Ti3C2T x The carrier and 0.4 g PVP were added to a 50 ml beaker, and then 20 ml deionized water was added. The mixture was ultrasonicated for 10 min and stirred at room temperature for 24 h to obtain mixture B. 2) Centrifuge the mixture B, wash it three times with deionized water, add 20 ml of deionized water, centrifuge and stir, and then disperse it to obtain PVP / Ti3C2T x Dispersion; add the corresponding mass of potassium chloroplatinate to another beaker according to the platinum loading of 1.0~5.0% mass fraction, and add 5ml of deionized water to dissolve it. Add the dissolved potassium chloroplatinate dropwise to the PVP / Ti3C2T x The dispersion was stirred for 24 h to obtain a mixture C; 3) 0.1 g of sodium borohydride solution was added dropwise to the mixture C and stirred for 6 h. After centrifugation, the mixture was washed with deionized water and anhydrous ethanol. The obtained solid was dried in a vacuum drying oven overnight to obtain Pt / S-Ti3C2T x catalyst.

2. The integrated method for hydrogen production and utilization based on a trickle bed continuous dehydrogenation reactor according to claim 1, characterized in that: The volume flow rate of the dehydrogenation feedstock in step S1 ranges from 0.001 μL to 43.349 mL / min.

3. The integrated method for hydrogen production and utilization based on a trickle bed continuous dehydrogenation reactor according to claim 1, characterized in that: In step S1, the temperatures in the preheater (4) and the reactor (8) are both set to 180°C; in step S5, the operating temperature of the proton exchange membrane fuel cell (23) is 80°C.

4. The integrated method for hydrogen production and utilization based on a trickle bed continuous dehydrogenation reactor according to claim 1, characterized in that: Preparation of Ti3C2T x The specific steps of the carrier are as follows: 1) Add 1.6g of LiF and 20ml of 12mol / L concentrated hydrochloric acid to a polypropylene beaker. Place the mixture on a magnetic stirrer and stir for 10 minutes to fully dissolve the LiF. Then add 1.0g of MAX (Ti3AlC2) to the beaker to obtain mixture A. To prevent severe heat release, the addition process is carried out in an ice-water bath. 2) The mixture A was heated to 50°C while stirring and reacted for 24 hours, after which the heating was stopped and the mixture was cooled to room temperature; the cooled mixture was centrifuged, washed with dilute hydrochloric acid solution three times, and then washed with deionized water until the pH was 6-7, and the lower layer of solid was obtained by centrifugation; 3) Dry the obtained solid in a vacuum drying oven overnight to obtain multilayer Ti3C2T x carrier.

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