Low-temperature hydrogen production method
By using carbonaceous materials and laser technology in the transparent reaction chamber, the method of efficient preparation of hydrogen under low temperature conditions is achieved, and the problems of high energy, harsh conditions and environmental pollution in the existing industrial hydrogen production methods are solved, and the advantages of low cost and environmental protection are low.
Patent Information
- Application Number
- CN202510116925.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-24
- Publication Date
- 2025-05-13
AI Technical Summary
In the existing industrial hydrogen production methods, fossil energy reforming hydrogen production has the disadvantages of high energy input, harsh reaction conditions, many side reactions, and difficult connection with downstream processes. Almost all hydrogen production reactions will release carbon dioxide, which is not environmentally friendly.
The hydrogen production method is adopted by filling the carbonaceous material into a transparent reaction chamber, passing it into a mixture of methane and carbon dioxide, and irradiating it with laser light to initiate a hydrogen production reaction, and finally the generated hydrogen and carbon monoxide are separated and collected.
It realizes rapid preparation of hydrogen under near room temperature, reduces energy consumption, reduces carbon dioxide emissions, has high catalyst stability, wide application range, and is suitable for large-scale industrial applications.
Smart Images
Figure CN119976735A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of hydrogen preparation, and in particular to a low-temperature hydrogen production method. Background Art
[0002] Hydrogen energy has a series of advantages, such as abundant sources, light weight, high energy density, clean and green, easy to store and regenerate. It is considered to be a high-quality alternative to traditional fossil energy and the ultimate energy source for human society. As climate issues become increasingly severe and extreme climate disasters become more frequent, hydrogen energy is highly anticipated and is a key breakthrough in solving climate issues. The hydrogen production process can be divided into geological hydrogen production process and industrial hydrogen production process.
[0003] Industrial hydrogen production methods include fossil energy hydrogen production, industrial by-product purification hydrogen production, water electrolysis hydrogen production, and other experimental hydrogen production processes. Fossil energy hydrogen production is the use of primary energy represented by coal and natural gas reforming to produce gray hydrogen and blue hydrogen. The production of gray hydrogen will emit carbon dioxide into the atmosphere, exacerbating global warming; hydrogen will be produced as a by-product in the chlor-alkali process, light hydrocarbon cracking and methanol synthesis process, and the hydrogen obtained from this accounts for 7% of the total global hydrogen production; alkaline water electrolysis hydrogen production is currently the most mature and lowest cost water electrolysis hydrogen production method, and is the main production method of environmentally friendly green hydrogen, but due to the overall high cost, water electrolysis hydrogen production accounts for only 4% of the total hydrogen production, and the high-purity hydrogen produced is almost only used for laboratory experiments, and does not have the conditions for large-scale industrial use; other hydrogen production methods such as solar hydrogen production, biomass hydrogen production, wind energy hydrogen production, nuclear energy hydrogen production, etc. are still in the experimental stage and have no application value for the time being.
[0004] In industrial hydrogen production, hydrogen production from fossil energy reforming accounts for the largest proportion. Among them, hydrogen production from methane steam reforming, hydrogen production from water gas reaction, and hydrogen production from methane partial oxidation mostly have disadvantages such as high energy input, harsh reaction conditions, many side reactions, and difficulty in connecting with downstream processes. Almost all hydrogen production reactions will release carbon dioxide, which is extremely unfriendly to the environment.
[0005] Methane and carbon dioxide dry reforming to produce hydrogen (CH4+CO2=2H2+2CO) is another common industrial fossil energy reforming hydrogen production process. It realizes the production of hydrogen while consuming methane and carbon dioxide, the two most important greenhouse gases, and may be an important way to slow global warming and achieve dual carbon goals. However, the reaction temperature of this process needs to be around 850°C, and the energy consumption is too high. At the same time, there are defects such as too many side reactions and harsh conditions, which make it difficult to apply on a large scale. The biggest constraint that the aforementioned various fossil energy reforming hydrogen production processes cannot be carried out more efficiently and economically is the choice of catalysts: precious metals such as Ru and Rh have high catalytic activity and good stability, but the high cost limits their wide application. Although metals such as Ni and Fe also have catalytic activity, the carbon single substance generated during the reaction will cover the catalyst, the reaction sites will continue to decrease, and eventually the catalytic ability will be completely lost. Summary of the invention
[0006] In order to overcome the deficiencies in the prior art, the present invention provides a rapid hydrogen production method that can be performed at near room temperature.
[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is:
[0008] A low-temperature hydrogen production method comprises the following steps:
[0009] Step 1: Loading the catalyst carbonaceous material into the transparent reaction chamber;
[0010] Step 2: Passing a mixture of methane and carbon dioxide into the transparent reaction chamber;
[0011] Step 3: irradiating the transparent reaction chamber with laser to induce hydrogen production reaction;
[0012] Step 4: Open the transparent reaction chamber to separate and collect the generated hydrogen and carbon monoxide.
[0013] In one embodiment, the carbonaceous material is one of graphite, asphalt, coal-based graphite, activated carbon, and / or the carbonaceous material is in powder form.
[0014] In one embodiment, the transparent reaction chamber is made of silicon dioxide.
[0015] In one embodiment, in step 2, the transparent reaction chamber needs to be evacuated before the methane and carbon dioxide mixed gas is introduced.
[0016] In one embodiment, the ratio of carbon dioxide to methane in the carbon dioxide and methane mixture is between 10 / 1 and 1 / 20.
[0017] In one embodiment, the ratio of carbon dioxide to methane in the carbon dioxide and methane mixture is between 10 / 1 and 1 / 13.
[0018] In one embodiment, in step 3, the laser power focused on the surface of the carbonaceous material per square micron is not less than 30 mW.
[0019] In one embodiment, in step 3, the temperature of the transparent reaction chamber is 20-100°.
[0020] In one embodiment, in step 3, the temperature of the transparent reaction chamber is 25-35°.
[0021] In order to solve the above technical problems, another technical solution adopted by the present invention is:
[0022] A low-temperature hydrogen production method comprises the following steps:
[0023] Step 1: taking a geological inclusion, wherein the geological inclusion has a transparent inclusion cavity, wherein the transparent inclusion cavity contains a mixture of methane and carbon dioxide, and carbonaceous materials;
[0024] Step 2: irradiating the transparent encapsulation cavity with a laser to induce a hydrogen production reaction;
[0025] Step 3: Open the transparent inclusion, separate and collect the generated hydrogen and carbon monoxide.
[0026] In one embodiment, the geological inclusion is dolomite or fluorite.
[0027] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:
[0028] (1) The applicable ratio of methane and carbon dioxide in the raw gas is relatively wide, and methane-rich or carbon dioxide-rich gases can be reacted, so as to achieve targeted consumption of methane or carbon dioxide.
[0029] (2) Compared with existing industrial hydrogen production methods, the methane-carbon dioxide photocatalytic hydrogen production reaction not only does not produce carbon dioxide emissions, but can also simultaneously consume two greenhouse gases, methane and carbon dioxide, making it more environmentally friendly.
[0030] (3) Photocatalytic hydrogen production from methane and carbon dioxide can be carried out at conditions close to room temperature, without requiring a lot of additional input energy to provide a high temperature environment, which can effectively reduce costs.
[0031] (4) The catalyst for photocatalytic hydrogen production from methane and carbon dioxide is a carbonaceous material. It will not be deactivated due to carbon deposition like traditional metal catalysts and has higher stability.
[0032] (5) The methane and carbon dioxide photocatalytic hydrogen production reaction can be carried out in fluid inclusions at the micron level, requiring a smaller transparent reaction chamber, which can further reduce costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Figure 1 This is a diagram of the experimental setup for Example 1;
[0034] Figure 2 The Raman spectra of the silica tube before and after hydrogen production and the electron microscope images of the catalyst graphite in Example 1;
[0035] Figure 3 The hydrogen production process of geological inclusions containing CH4, CO2, asphalt, etc. in dolomite in Example 2;
[0036] Figure 3a The anti-Stokes spectral line and the Stokes spectral line of dolomite at different temperatures in Example 2;
[0037] Figure 3b The temperature calibration curve and temperature measurement results of dolomite in Example 2;
[0038] Figure 3c is the result of laser temperature measurement;
[0039] Figure 4a This is a microscopic photograph of geological inclusions before the hydrogen production reaction in Example 3;
[0040] Figure 4b This is a two-dimensional Raman scanning image of hydrogen before the hydrogen production reaction in Example 3;
[0041] Figure 4c This is a two-dimensional Raman scanning image of hydrogen after the hydrogen production reaction in Example 3;
[0042] Figure 5 The Raman spectrum diagram of the relationship between laser irradiation time and hydrogen production in Example 4;
[0043] Figure 6 This is a curve showing the change of hydrogen peak height with laser irradiation time in Example 5. DETAILED DESCRIPTION
[0044] The present invention is further described below with reference to the accompanying drawings and specific embodiments:
[0045] Example 1
[0046] like Figure 1-2 As shown, this embodiment provides a low-temperature hydrogen production method, comprising the following steps:
[0047] Step 1: Load the catalyst carbonaceous material into the transparent reaction chamber.
[0048] The carbonaceous material is ground into powder to increase the catalytic area. The reaction chamber is a transparent reaction chamber to ensure that the laser can pass through the container wall. In this embodiment, the carbonaceous material is graphite. In other embodiments, the carbonaceous material can be one of asphalt, coal-based graphite, and activated carbon. In this embodiment, the transparent reaction chamber is a molten capillary silicon tube, which is made of silicon dioxide. The specifications of the molten capillary silicon tube used in this embodiment are as follows: inner diameter 250μm, outer diameter 350μm, and circular cross-section. First, the polyimide protective layer covering the surface of the molten capillary silicon tube is burned off with an oxyhydrogen flame, and then one end of the molten capillary silicon tube is welded and sealed with an oxyhydrogen flame. The carbonaceous material powder is placed on a clean weighing paper, and a clean ceramic plate is used to push the graphite into the open end of the silicon tube, and a centrifuge is used to centrifuge the graphite to the welded end. In other embodiments, the transparent reaction chamber can also be made of other transparent materials, such as calcium carbonate and calcium fluoride.
[0049] Step 2: Pass a mixture of methane and carbon dioxide into the transparent reaction chamber.
[0050] Connect the molten silicon capillary tube to the vacuum line through a high-pressure valve, introduce a mixture of methane and carbon dioxide after evacuation, and then seal the open end with hydrogen-oxygen flame welding.
[0051] Step 3: Use laser to irradiate the transparent reaction chamber to trigger the hydrogen production reaction.
[0052] The laser used is a green laser with a wavelength of 532nm. The laser is focused on a circular area with a diameter of about 1μm on the surface of the carbonaceous material. When the laser power focused on the surface of the carbonaceous material reaches 30mW per square micron, rapid hydrogen production can be achieved.
[0053] Step 4: Open the transparent reaction chamber to separate and collect the generated hydrogen and carbon monoxide.
[0054] Figure 1 This is a diagram of the experimental setup. The sample chamber is filled with graphite, methane, and carbon dioxide. When the laser is focused on the graphite surface, hydrogen and carbon monoxide can be produced.
[0055] Figure 2 The Raman spectra before and after hydrogen production of the low-temperature hydrogen production method in this embodiment and the electron microscope image of the catalyst graphite used are shown. It can be seen from the Raman spectra that before the reaction, that is, after the completion of step 2, there are methane and carbon dioxide in the transparent reaction chamber, and no hydrogen and carbon monoxide. After the reaction, that is, after the completion of step 3, methane and carbon dioxide are reduced, and hydrogen and carbon monoxide are produced. Before the reaction, carbon dioxide / methane = 9.3 / 1, and after the reaction, methane is consumed in large quantities, carbon dioxide / methane = 49.2 / 1, hydrogen / methane = 10.3 / 1.
[0056] The low-temperature hydrogen production method in this embodiment does not additionally heat the transparent reaction chamber in step 3. The temperature of the transparent reaction chamber is about 30° from room temperature. In some embodiments, in step 3, the temperature of the transparent reaction chamber ranges from 20 to 100°. In some embodiments, in step 3, the temperature of the transparent reaction chamber ranges from 20 to 35°.
[0057] Example 2
[0058] This embodiment provides a low-temperature hydrogen production method, comprising the following steps:
[0059] Step 1: Take a geological inclusion, specifically dolomite, the geological inclusion has a transparent inclusion cavity, and the transparent inclusion cavity contains a mixture of methane and carbon dioxide, and carbonaceous materials;
[0060] Step 2: Use laser to irradiate the transparent encapsulation cavity, specifically irradiate the surface of the carbonaceous material therein, to induce a hydrogen production reaction;
[0061] Step 3: Open the transparent inclusion, separate and collect the generated hydrogen and carbon monoxide.
[0062] like Figure 3 The Raman spectra of the transparent encapsulation cavity in the dolomite in this embodiment before and after the hydrogen production reaction are shown. Before the reaction, i.e., in step 1, the components of the transparent encapsulation cavity are methane, carbon dioxide, asphalt and a small amount of ethane. After the transparent encapsulation cavity is irradiated with laser, during the reaction, i.e., in step 2, the carbon dioxide in the transparent encapsulation cavity gradually decreases until it disappears. After the reaction, i.e., after step 2, hydrogen and carbon monoxide are produced.
[0063] Since the methane catalytic hydrogen production reaction is usually carried out at high temperature, in order to explore whether laser heating is the controlling factor of hydrogen production in the transparent encapsulation cavity of the present invention, we explored the effect of different laser powers on the temperature of the dolomite in Example 2. The signal intensity ratio of the anti-Stokes position to the Stokes position of the same sample of dolomite indicates the ratio of the number of particles in the excited state and the ground state. According to the Boltzmann distribution, Figure 3a In the figure, the Raman spectra of the same site of dolomite at different temperatures are shown. All peaks are characteristic peaks of dolomite. When the intensity of the Stokes lines is the same, the intensity of the anti-Stokes lines increases with increasing temperature, indicating that the intensity ratio of the anti-Stokes lines to the Stokes lines in the Raman spectrum is related to temperature. Figure 3bIn the embodiment, a quantitative relationship between the intensity ratio of the anti-Stokes peak and the Stokes peak of the same vibration of dolomite at different temperatures was established, and the peak intensity was characterized by the peak area and the peak height, respectively, so as to obtain the two temperature calibration curves in the figure. The anti-Stokes / Stokes spectrum intensity ratio corresponding to the sample dolomite was projected onto the temperature-anti-Stokes / Stokes signal intensity ratio curve, and it was obtained that the temperature of the dolomite in Example 2 in step 2 was about 27-32°C. In addition, as Figure 3c As shown, we used three objective lenses, X5 objective lens, X50 objective lens, and X100 objective lens, to measure the temperature values of the K-type thermocouple irradiated with a green laser of 532nm wavelength at 100% power and 50% power, respectively. The temperature of the green laser of 532nm wavelength using the X50 objective lens at 100% power was measured to be 38°, which is close to the above result of 27-32°. In summary, it can be confirmed that the laser has limited effect on the temperature of the dolomite sample, and the hydrogen production method in the present invention is a low-temperature hydrogen production method.
[0064] Example 3
[0065] The difference between the low-temperature hydrogen production method in this embodiment and that in embodiment 2 is that in this embodiment, the geological inclusion is fluorite (the main component is CAF2). Before the hydrogen production reaction, carbon dioxide / methane = 1 / 12.2, and after the hydrogen production reaction, carbon dioxide disappears, and hydrogen / methane = 1 / 11.7.
[0066] Figure 4a This is a micrograph of the transparent inclusion cavity in fluorite before the hydrogen production reaction. Figure 4a It can be seen that there is asphalt in the transparent package cavity. Figure 4b This is the Raman 2D scanning image of hydrogen before the hydrogen production reaction. Figure 4c This is a Raman 2D scan image of hydrogen after the hydrogen production reaction. In order to confirm that the hydrogen in the transparent encapsulation cavity is a newly generated product, rather than the possibility that the asphalt structure changes under the laser to release previously stored hydrogen, we performed a 10μm×10μm Raman 2D scan of the transparent encapsulation cavity before and after the reaction with a resolution of 0.3μm and scanned the area at 570-600cm -1 The results show that there is no hydrogen in the transparent cavity before the reaction, but after the reaction, the hydrogen signal is very obvious and only distributed in the transparent cavity outside the asphalt.
[0067] Example 4
[0068] This example and Example 3 both use fluorite as the geological inclusion. In this example, before the reaction, the carbon dioxide / methane ratio is 1 / 10.7. After the reaction, the carbon dioxide disappears, the hydrogen / methane ratio is 1 / 2.6, and the carbonaceous component is asphalt. Figure 5 This is the Raman spectrum of the relationship between laser irradiation time and hydrogen production in Example 4. Figure 5It can be seen that the hydrogen production reaction in the transparent encapsulation cavity is very fast, and an obvious hydrogen signal can be observed within 10 seconds after the laser is focused on the asphalt surface in the transparent encapsulation cavity.
[0069] Example 5
[0070] This example and Example 3 both use fluorite as the geological inclusion. In this example, before the reaction, the carbon dioxide / methane ratio is 1 / 11.1. After the reaction, the carbon dioxide disappears, the hydrogen / methane ratio is 1 / 7, and the carbonaceous component is asphalt. Figure 6 is the curve of hydrogen peak height changing with laser irradiation time, Figure 6 It can be seen that after about 30 seconds, the hydrogen signal intensity is close to stable, and hydrogen is mainly produced in this stage. The entire reaction can be completed in about 60 seconds, and hydrogen and carbon monoxide are produced in the transparent package cavity.
[0071] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.
Claims
1. A low-temperature hydrogen production method, characterized in that: The following steps are involved: Step 1: Loading the catalyst carbonaceous material into the transparent reaction chamber; Step 2: Passing a mixture of methane and carbon dioxide into the transparent reaction chamber; Step 3: irradiating the transparent reaction chamber with laser to induce hydrogen production reaction; Step 4: Open the transparent reaction chamber to separate and collect the generated hydrogen and carbon monoxide.
2. The low temperature hydrogen production method according to claim 1, characterized in that: The carbonaceous material is one of graphite, asphalt, coal-based graphite, and activated carbon, and / or the carbonaceous material is in powder form.
3. The low temperature hydrogen production method according to claim 1, characterized in that: The transparent reaction chamber is made of silicon dioxide.
4. The low temperature hydrogen production method according to claim 1, characterized in that: In step 2, the transparent reaction chamber needs to be evacuated before the methane and carbon dioxide mixed gas is introduced.
5. The low temperature hydrogen production method according to claim 1, characterized in that: The ratio of carbon dioxide to methane in the carbon dioxide and methane mixed gas is 10 / 1 to 1 / 20.
6. The low temperature hydrogen production method according to claim 1, characterized in that: In step 3, the laser power focused on the surface of the carbonaceous material per square micron is not less than 30 mW.
7. The low temperature hydrogen production method according to claim 1, characterized in that: In step 3, the temperature of the transparent reaction chamber is 20-100°.
8. The low temperature hydrogen production method according to claim 7, characterized in that: In step 3, the temperature of the transparent reaction chamber is 25-35°.
9. A low-temperature hydrogen production method, characterized in that: The following steps are involved: Step 1: taking a geological inclusion, wherein the geological inclusion has a transparent inclusion cavity, wherein the transparent inclusion cavity contains a mixture of methane and carbon dioxide, and carbonaceous materials; Step 2: irradiating the transparent encapsulation cavity with a laser to induce a hydrogen production reaction; Step 3: Open the transparent inclusion, separate and collect the generated hydrogen and carbon monoxide.
10. The low temperature hydrogen production method according to claim 9, characterized in that: The geological inclusion is dolomite or fluorite.