Membrane catalysis in-situ reaction tank based on combination of X-ray absorption spectrum and multi-mode spectrum

Abstract

The invention belongs to the technical field of scientific instruments and heterogeneous catalytic characterization, and discloses a membrane catalysis in-situ reaction tank based on combination of an X-ray absorption spectrum and a multi-mode spectrum, comprising: a housing provided with a mounting cavity; the reaction platform is arranged on the mounting cavity of the shell; the cover body assembly is arranged on the reaction platform, so that a reaction cavity is formed between the cover body assembly and the reaction platform, and a sample reacts in the reaction cavity; the cover body assembly is provided with a window used for installing optical window sheets, an acute included angle is formed between the central axis of the window and a base plane provided by the reaction platform, and the optical window sheets comprise a first group of window sheets suitable for X-rays and a second group of window sheets suitable for molecular spectrums; the fluid transmission unit comprises a gas inlet pipe for inputting gas reactants into the reaction cavity and a gas outlet pipe for discharging gas in the reaction cavity, the gas inlet pipe is mounted on the cover body assembly, and the gas outlet pipe is mounted on the reaction platform.

Description

Technical Field

[0001] This invention belongs to the field of scientific instruments and multiphase catalysis characterization technology, specifically relating to a membrane catalytic in-situ reaction cell based on the combined use of X-ray absorption spectroscopy and multimode spectroscopy. Background Technology

[0002] In traditional catalytic reaction studies, the catalytic reaction process is often difficult to observe directly, especially in membrane reactor (MFR) technology. MFR technology couples the catalytic reaction with the product separation process, breaking thermodynamic equilibrium limitations and significantly improving catalytic performance and product selectivity. It is widely used in processes such as natural gas conversion, hydrogen purification, and methanol reforming for hydrogen production. To gain a deeper understanding of the structure-activity relationship of membrane catalysts under actual operating conditions, in-situ or operant characterization is crucial.

[0003] In recent years, X-ray absorption spectroscopy (XAS) has been widely used as an advanced characterization tool in the research of nanomaterials and catalysts. XAS can provide information about the electronic structure and coordination environment of catalysts, which is crucial for understanding the activity and selectivity of catalysts. At the same time, multimode spectroscopy (including infrared spectroscopy, Raman spectroscopy, and ultraviolet-visible spectroscopy) is also widely used in biological and chemical research because it can simultaneously provide information on molecular vibrations and adsorbed species.

[0004] However, existing in-situ spectroscopic characterization devices still have the following significant limitations: 1. Sample shape limitation: Most mainstream in-situ reaction cells are designed for powder or tablet samples, which cannot effectively load, fix and seal tubular membrane catalysts with curvature (such as hollow fiber membranes).

[0005] 2. Limitations of Single Characterization: Current in-situ reaction cells typically only allow for single-spectral measurements. X-ray absorption spectroscopy can provide the electronic structure and fine coordination environment of the catalyst, while infrared or Raman spectroscopy can detect surface adsorbed species and molecular vibrational information.

[0006] 3. High temperature and high pressure conflict with optical path: Under high temperature and high pressure conditions, the reaction cell requires thick-walled metal and a complex cooling system, which often blocks the optical path. In particular, the fluorescence mode of XAS usually requires the detector to be at 90° to the incident light, and diffuse infrared also requires a specific incident reflection angle. Arranging multiple windows in a limited space without interference is a huge engineering challenge. Summary of the Invention

[0007] In view of this, in order to solve the problems mentioned in the background art, the purpose of the present invention is to provide a membrane catalytic in-situ reaction cell based on the combination of X-ray absorption spectroscopy and multimode spectroscopy.

[0008] To achieve the above objectives, the present invention provides the following technical solution: A membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy, comprising: The outer casing has a mounting cavity. The reaction platform is located in the mounting cavity of the outer casing; A cover assembly is disposed on the reaction platform, such that a reaction chamber is formed between the cover assembly and the reaction platform, and the sample reacts within the reaction chamber; the cover assembly is provided with a window for mounting an optical window, the central axis of the window forming an acute angle with the base plane provided by the reaction platform, and the optical window includes a first set of windows suitable for X-rays and a second set of windows suitable for molecular spectroscopy; The fluid transmission unit includes an inlet pipe for inputting gaseous reactants into the reaction chamber and an outlet pipe for discharging gas from the reaction chamber. The inlet pipe is mounted on the cover assembly, and the outlet pipe is mounted on the reaction platform.

[0009] Preferably, the acute angle formed between the central axis of the window and the base plane provided by the reaction platform is 40° to 50°.

[0010] Preferably, the window includes an entrance window and an exit window that are arranged opposite to each other; The optical path configuration of the in-situ reaction cell is as follows: the incident light is horizontally incident through the incident window in the window, and the reflected light excited by the reaction platform is emitted through the exit window in the window in a direction perpendicular to the incident light and is received by the detector.

[0011] Preferably, the window includes a first window for installing the first set of window panes and a second window for installing the second set of window panes, wherein the first center line connecting the incident window and the exit window in the first window and the second center line connecting the incident window and the exit window in the second window are intersected. The intersection angle between the first center line and the second center line is 90°.

[0012] Preferably, the first set of optical window materials is selected from one or more combinations of the following material groups: diamond, beryllium, polyimide, and ultra-thin glass; the second set of optical window materials is selected from one or more combinations of the following material groups: zinc selenide, calcium fluoride, potassium bromide, sodium chloride, magnesium fluoride, sapphire, quartz, and silicon.

[0013] Preferably, the cover assembly includes a dome with a hemispherical structure and fasteners for sealing the dome to the reaction platform by means of a sealing ring; In the sealed and engaged state, the fasteners are fitted onto the outside of the dome and secured to the outer shell by fastening bolts.

[0014] Preferably, the reaction platform includes a carrier plate having an arc-shaped groove and a lateral interface seat thereon, the lateral interface seat being aligned and configured at both ends of the arc-shaped groove for the passage and sealing of tubular samples.

[0015] Preferably, the lateral interface seat and the tubular sample inserted therein are sealed by a flexible sealing structure, the flexible sealing structure including a flexible pressure ring sleeved on the tubular sample and a ferrule nut that presses the flexible pressure ring tightly against the tubular sample; the flexible pressure ring is selected from graphite rings, fluororubber rings, perfluoroether rubber rings or metal C-rings.

[0016] Preferably, the lower part of the support plate is provided with a support column that can be inserted and cooperated with the heating rod and the thermocouple. The center of the support column is provided with a central flow channel that extends from the air outlet pipe to the arc-shaped groove. The end of the thermocouple extends into the arc-shaped groove through the central flow channel to abut against the tubular sample.

[0017] Preferably, the outer shell is provided with a circulating cooling water channel surrounding the outside of the reaction platform; The materials of the outer shell and the reaction platform are selected from high-temperature and corrosion-resistant alloys, including but not limited to 316 stainless steel, 304 stainless steel, Hastelloy, Inconel, or titanium alloy.

[0018] Compared with the prior art, the present invention has the following advantages: This invention provides a membrane catalytic in-situ reaction cell based on the combined use of X-ray absorption spectroscopy and multi-mode spectroscopy. A specially structured reaction platform enables the installation and sealing of tubular samples. By optimizing the cover structure and the mounting orientation of the optical windows, the optical detection paths of X-rays and molecular spectra such as infrared, Raman, or ultraviolet-visible spectra are spatially overlapped within the reaction chamber, thus forming an optical path configuration that satisfies the combined use of X-ray absorption spectroscopy and multi-mode spectroscopy. This facilitates in-situ coupling characterization of X-ray absorption spectroscopy (fluorescence mode) and multi-mode spectroscopy (diffuse reflectance infrared, Raman spectroscopy) under high temperature and high pressure conditions. Furthermore, it effectively solves the problem of optical path obstruction in multi-field coupling characterization, providing comprehensive data support for the study of reaction mechanisms. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is an exploded view of the present invention; Figure 3 This is a schematic diagram of the reaction platform in this invention; Figure 4This is an exploded view of the reaction platform in this invention; Figure 5 This is a schematic diagram of the structure of the cover assembly in this invention; Figure 6 This is a schematic diagram of the optical path principle of the cover assembly in this invention; Figure 7 The in-situ infrared spectrum of methanol steam reforming performed using the in-situ reaction cell of this invention; In the diagram: Outer shell - 10; Circulating cooling water channel - 11; Reaction platform - 20; Support plate - 21; Arc-shaped groove - 22; Side interface seat - 23; Flexible pressure ring - 24; Compression nut - 25; Support column - 26; Heating rod - 27; Thermocouple - 28; Central flow channel - 29; Cover assembly - 30; Optical window - 31; Window - 32; First window - 321; Second window - 322; Dome - 33; Sealing ring - 34; Fastener - 35; Fastening bolt - 36; Inlet pipe - 40; Outlet pipe - 50. Detailed Implementation

[0020] To further understand the content of this invention, a detailed description of the invention is provided in conjunction with the accompanying drawings and embodiments. The structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art, and are not intended to limit the implementation conditions of the invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effects and objectives achieved by the invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and not intended to limit the scope of implementation. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention. It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein.

[0021] like Figure 1 and Figure 2As shown, the present invention provides an in-situ membrane catalytic reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy, comprising a shell 10, a reaction platform 20, a cover assembly 30, and a fluid transmission unit. The shell 10 has a mounting cavity for mounting the reaction platform 20, and the cover assembly 30 is mounted on the reaction platform 20, forming a reaction chamber between the cover assembly 30 and the reaction platform 20, where the sample reacts. The fluid transmission unit includes an inlet pipe 40 for inputting gaseous reactants into the reaction chamber and an outlet pipe 50 for venting gas from the reaction chamber. The inlet pipe 40 is mounted on the cover assembly 30, and the outlet pipe 50 is mounted on the reaction platform 20. This reaction cell is used in gas-solid catalytic systems and, when coupled with spectroscopic characterization instruments, obtains structural information of solid catalysts under real reaction conditions, providing important support for catalyst design and development.

[0022] refer to Figure 2 As shown, in some embodiments, the materials of the outer shell 10 and the reaction platform 20 are selected from high-temperature and corrosion-resistant alloys, including but not limited to 316 stainless steel, 304 stainless steel, Hastelloy, Incoln nickel alloy, or titanium alloy. The outer shell 10 is integrally formed, serving as a pressure-bearing and support structure. To cope with the internal reaction temperature, which may reach over 600°C, the inner wall of the outer shell 10 is precision-machined with circulating cooling water channels 11 surrounding the outer side of the mounting cavity. The two ends of the circulating cooling water channels 11 are connected to a laboratory chiller via cooling water connectors. This structural design ensures that the surface temperature of the outer shell 10 is maintained near room temperature.

[0023] refer to Figure 3 and Figure 4 As shown, in some embodiments, the reaction platform 20 includes an upper support plate 21 and a lower support column 26. A heating rod 27 and a thermocouple 28 are inserted into the support column 26. A central flow channel 29, extending from the gas outlet pipe 50 to the arc-shaped groove 22, is also provided at the center of the support column 26. The end of the thermocouple 28 extends through the central flow channel 29 into the arc-shaped groove 22 to abut against a tubular sample, thereby measuring the catalyst temperature. It should be noted that both the heating rod 27 and the thermocouple 28 are connected to an external PID temperature control system to achieve real-time and precise control of the catalyst temperature, specifically within a temperature range of room temperature to 800°C.

[0024] refer to Figure 3 and Figure 4As shown, in some embodiments, the support plate 21 is provided with an arc-shaped groove 22 and a lateral interface seat 23. The lateral interface seat 23 is aligned and configured at both ends of the arc-shaped groove 22 for the passage and sealing of the tubular sample. It should be noted that the radius of curvature of the arc-shaped groove 22 is slightly larger than the outer diameter of the tubular sample of the membrane catalyst, thereby achieving a perfect balance between mechanical stability and thermal conductivity. When the tubular sample is placed in the arc-shaped groove 22, due to the difference in radius, a three-line support structure is formed between the tubular sample and the arc-shaped groove 22: the two sides of the tubular sample make elastic contact with the arc surface of the groove, and the bottom forms the main support surface. This contact method not only allows the tubular sample to automatically center and be stably placed in the arc-shaped groove 22, avoiding displacement problems caused by thermal expansion under high temperature conditions, but also significantly improves the thermal conductivity by increasing the effective contact area. In addition, this structure can effectively reduce contact stress, avoid local overheating of the tubular sample of the membrane catalyst, and ensure the stability and consistency of the catalytic reaction.

[0025] refer to Figure 4 As shown, in some embodiments, to accommodate the fragility of ceramic or carbon molecular sieve membrane tubes, the lateral interface seat 23 is sealed to the tubular sample inserted therein via a flexible sealing structure. This flexible sealing structure includes a flexible pressure ring 24 fitted onto the tubular sample and a clamping nut 25 that presses the flexible pressure ring 24 tightly against the tubular sample. Thus, when the clamping nut 25 is tightened, the flexible pressure ring 24 deforms and tightly adheres to the surface of the tubular sample, forming a uniform sealing contact surface. The clamping nut 25 generates a stable clamping force through threaded fastening, ensuring that the flexible sealing structure maintains reliable airtightness under various reaction conditions, effectively preventing gas leakage. Furthermore, this connection method also considers the thermal expansion factors under high-temperature and high-pressure reaction conditions; that is, the elastic deformation of the flexible pressure ring 24 allows the tubular membrane sample to undergo slight axial displacement when heated. Specifically, the flexible pressure ring 24 is selected from graphite rings, fluororubber rings, perfluoroether rubber rings, or metal C-rings, thus flexibly adapting to high-temperature reaction conditions.

[0026] refer to Figure 5 As shown, in some embodiments, the cover assembly 30 is provided with a window 32 for mounting an optical window 31, the central axis of the window 32 forming an acute angle with the base plane provided by the reaction platform 20, and the optical window 31 including a first set of windows suitable for X-rays and a second set of windows suitable for molecular spectroscopy. For example: The first set of window materials of the optical window 31 is selected from one or more combinations of the following material groups: diamond, beryllium, polyimide, and ultra-thin glass; The second set of window materials for the optical window 31 is selected from one or more combinations of the following material groups: zinc selenide, calcium fluoride, potassium bromide, sodium chloride, magnesium fluoride, sapphire, quartz, and silicon. Among them, quartz windows can be used for in-situ Raman spectroscopy and in-situ ultraviolet spectroscopy characterization, while windows made of zinc selenide, calcium fluoride, potassium bromide, etc., can be used for in-situ infrared spectroscopy characterization.

[0027] Specifically, the window 32 design of this reaction cell integrates the X-ray window and the molecular spectroscopy window at an acute angle onto the cover assembly 30, achieving a technological breakthrough in multimodal in-situ characterization. Its core advantages include: through the precise window 32 angle design, the optical detection paths of X-rays and molecular spectra such as infrared, Raman, or ultraviolet-visible spectra are spatially overlapped within the reaction chamber, enabling simultaneous real-time correlation measurement of X-ray absorption spectra and molecular spectra, providing comprehensive data support for reaction mechanism research. The optimized optical path design significantly reduces cross-interference between different spectroscopic signals, thus facilitating the accurate capture of structural information during the reaction process. This innovative design breaks through the limitations of traditional single-type characterization in reaction cells, providing a powerful tool platform for in-situ multi-scale research of complex chemical reactions.

[0028] In one example, the acute angle formed between the central axis of the window 32 and the base plane provided by the reaction platform 20 is 40° to 50°, preferably 45°. This effectively meets the optical path construction requirements for X-ray and infrared, Raman, or ultraviolet-visible molecular spectra within a limited space, while minimizing scattering background. Specifically, as... Figure 6 As shown, in the constructed optical path, the window 32 includes an incident window and an exit window arranged opposite to each other. That is, the optical path configuration is configured such that: the incident light is horizontally incident through the incident window in the window 32, and the reflected light excited by the reaction platform 20 is emitted through the exit window in the window 32 in a direction perpendicular to the incident light and is received by the detector.

[0029] To integrate X-ray windows (first set of windows) and molecular spectroscopy windows (second set of windows) on the cover assembly 30, the cover assembly 30 preferably includes a dome 33 with a hemispherical structure. The window 32 includes a first window 321 for mounting the first set of windows and a second window 322 for mounting the second set of windows. The first window 321 and the second window 322 are quadrant-aligned relative to the dome 33, meaning that the first center line connecting the incident and exit windows in the first window 321 intersects with the second center line connecting the incident and exit windows in the second window 322. It should be noted that the intersection angle between the first and second center lines is 90°.

[0030] Under this structural design, two sets of orthogonal reflection optical paths are constructed through four 45° symmetrically tilted windows 32, enabling precise synchronous detection using multispectral technology. The hemispherical dome 33 and the four 45° symmetrically distributed windows 32 combine to form a unique geometric structure, effectively suppressing stray light interference and significantly improving signal quality. This design supports dynamic monitoring of the coupled catalytic reaction and product separation process, directly linking the evolution of catalyst structure and surface intermediate species under the synergistic effect of reaction-separation, providing multidimensional data for reaction mechanism research. The second window 322 adopts a standardized modular interface, compatible with windows of different materials suitable for various characterization techniques such as infrared, Raman, or ultraviolet-visible. This allows for in-situ coupled characterization of X-ray absorption spectroscopy (fluorescence mode) with diffuse reflectance infrared and Raman spectroscopy under high temperature and high pressure conditions by changing the windows. This flexible scalability enables researchers to quickly configure the optimal optical combination scheme according to specific experimental needs. In addition, the hemispherical dome 33 not only provides excellent optical performance but also ensures the stability and reliability of the reaction cell under various conditions, suitable for the reaction requirements under high temperature and high pressure conditions.

[0031] refer to Figure 2 and Figure 5 As shown, in some embodiments, the cover assembly 30 further includes a fastener 35 that seals the dome 33 onto the reaction platform 20 via a sealing ring 34. The sealing ring 34 is an O-ring that fits between the reaction platform 20 and the dome 33, serving a sealing function. The fastener 35 is a fixing plate structure with an inner hole and a fixing hole. The inner hole of the fastener 35 is an arc-shaped structure that matches the dome 33. The fixing hole is used to install a fastening bolt 36, and the outer shell 10 also has a threaded hole corresponding to the fixing hole. The fastening bolt 36 passes through the fixing hole and is fastened in the threaded hole, thereby clamping and pressing the inner edge of the fastener 35 against the outer periphery of the dome 33. This effectively ensures the sealing effect of the reaction chamber, and the structure is simple and easy to assemble and disassemble.

[0032] In summary, the membrane catalytic in-situ reaction cell applicable to X-ray absorption spectroscopy and multimode spectroscopy in this application is implemented as follows: First, a heating rod 27 and a thermocouple 28 are inserted into the support column 26 of the reaction platform 20. The reaction platform 20 is connected to the outer shell 10. Then, at room temperature, a tubular ceramic membrane tube or carbon molecular sieve membrane is fixed in the arc-shaped groove 22 at the center of the reaction platform 20, and the two ends of the tubular sample are sealed using the lateral interface seats 23 on both sides of the reaction platform 20. Then, the sealing ring 34 and the dome 33 are placed in sequence and fixed using fasteners 35 and fastening bolts 36. The required test windows are installed in the four windows 32 on the dome 33. Then, the assembled reaction cell is placed in the test optical path of the required spectrometer. Cooling circulating water is introduced into the circulating cooling water channel 11, connecting the heating rod 27 and the thermocouple 28 to the PID temperature control system. Finally, the gaseous reactants are introduced into the reaction chamber through the inlet pipe 40, which is installed at the center of the dome 33 to ensure that the gaseous reactants accurately sweep across the outer wall of the tubular sample (catalyst coating side). The reacted gas converges into the central flow channel 29 and is discharged through the outlet pipe 50 after passing through the central flow channel 29. The required reaction temperature and heating rate are set by the PID temperature control system, and the signal of the reaction system is detected to obtain information on the catalyst, reactants, intermediates and products in the system.

[0033] In this embodiment, the surface species evolution of Cu / ZnO / Al2O3 catalyst coupled with carbon molecular sieve membrane (CMS) in methanol steam reforming reaction was monitored in situ using the above-mentioned hemispherical dome-shaped membrane catalytic in situ reaction cell. This verifies the ability of the in situ reaction cell to study the mechanism of complex heterogeneous catalytic reactions under high temperature conditions.

[0034] 1. Preparation of experimental materials Membrane catalyst preparation: Cellulose-based carbon molecular sieve hollow fiber membrane (named CMS-700, with an outer diameter of approximately 180 μm) was prepared by dry-wet spinning and subsequent high-temperature carbonization at 700℃.

[0035] Catalyst loading: Commercial Cu / ZnO / Al2O3 catalyst (particle size 60-80 mesh) was mixed with KBr powder in a certain proportion and pressed into tablets or coated on the outside of CMS-700 membrane tubes to simulate the membrane reactor configuration.

[0036] In-situ cell assembly: The prepared membrane catalyst tube is placed in the arc-shaped groove 22 of the reaction platform 20. Both ends of the membrane tube are sealed in the side interface seat 23 by flexible pressure rings 24 (graphite). A zinc selenide (ZnSe) window is installed at the second window 322 position of the dome 33 to meet the requirements of infrared spectroscopy testing.

[0037] 2. Testing Process Gas connection: The reaction feed gas (methanol / water vapor / argon) is introduced into the outer side (shell side) of the membrane tube, and the scavenging gas (argon) is introduced into the inner side (tube side) of the membrane tube, so as to remove the generated hydrogen in situ by utilizing the selective permeation function of the membrane.

[0038] In-situ infrared testing: The in-situ reaction cell was placed in the optical path of a Fourier transform infrared spectrometer (FTIR). First, an H2 / Ar mixed gas was introduced at 300℃ to perform in-situ reduction and activation of the catalyst. Then, the temperature was lowered to 25℃, and the methanol / water vapor feed gas (water-methanol molar ratio 1.3) was switched to adsorption for 30 minutes.

[0039] Temperature-dependent reaction monitoring: The heating rod 27 was activated, and the temperature was increased from room temperature to 250°C at a rate of 10°C / min. During this process, the infrared spectral signal of the catalyst surface was acquired in real time through the ZnSe window using an infrared spectrometer.

[0040] 3. Experimental Results and Apparatus Verification Sealing and stability verification: Throughout the heating and reaction process (up to 250℃), the shell temperature remained below 40℃, indicating that the water cooling system was working normally; no condensation or cracking occurred on the ZnSe window, and the infrared signal intensity was stable, proving the sealing reliability of the device in high temperature and humid environment.

[0041] Spectral data analysis: such as Figure 7 As shown (corresponding to experimental data), as the temperature increases, the temperature at 1056 cm⁻¹... -1 The intensity of the characteristic peak at 1589 cm⁻¹ (attributed to the surface methoxy species *OCH₃) gradually decreases; meanwhile, the intensity of the peak at 1589 cm⁻¹ gradually decreases. -1 and 1358cm -1 The characteristic peaks (attributed to formate species *CHOO) gradually appear and intensify.

[0042] Mechanism revealed: By comparing the spectral data of the in-situ reaction cell mode of this invention with those of the conventional packed bed mode, it was found that the consumption initiation temperature (approximately 90°C) and complete consumption temperature (approximately 180°C) of methoxy species in the in-situ reaction cell mode of this invention are significantly lower than those in the conventional mode. This directly proves that the in-situ reaction cell of this invention successfully achieves in-situ removal of hydrogen, thereby kinetically accelerating the rate-determining step of methoxy dehydrogenation.

[0043] In summary, the in-situ reaction cell of this invention can not only physically contain and seal the fragile CMS hollow fiber membrane, but its excellent optical window design also allows for high-quality in-situ infrared spectroscopy acquisition, successfully capturing the dynamic changes of reaction intermediate species, thus demonstrating its practicality and advanced nature in the study of membrane catalytic reaction mechanisms.

[0044] In the description of this invention, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0045] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A membrane-catalyzed in-situ reaction cell based on X-ray absorption spectroscopy coupled with multimode spectroscopy, characterized in that, include: The outer casing (10) has a mounting cavity thereon; A reaction platform (20) is provided on the mounting cavity of the outer casing (10); A cover assembly (30) is disposed on the reaction platform (20) such that a reaction chamber is formed between the cover assembly (30) and the reaction platform (20), and the sample reacts in the reaction chamber; a window (32) for mounting an optical window (31) is provided on the cover assembly (30), and an acute angle is formed between the central axis of the window (32) and the base plane provided by the reaction platform (20); the optical window (31) includes a first set of windows suitable for X-rays and a second set of windows suitable for molecular spectroscopy; The fluid transmission unit includes an inlet pipe (40) for inputting gaseous reactants into the reaction chamber and an outlet pipe (50) for discharging gas from the reaction chamber. The inlet pipe (40) is mounted on the cover assembly (30), and the outlet pipe (50) is mounted on the reaction platform (20).

2. The in-situ membrane catalytic reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy according to claim 1, characterized in that: The acute angle formed between the central axis of the window (32) and the base plane provided by the reaction platform (20) is 40° to 50°.

3. The membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy as described in claim 1, characterized in that: The window (32) includes an entrance window and an exit window that are set opposite to each other; The optical path configuration of the in-situ reaction cell is configured such that the incident light is incident horizontally through the incident window in the window (32), and the reflected light excited by the reaction platform (20) is emitted in a direction perpendicular to the incident light through the exit window in the window (32) and received by the detector.

4. The membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy as described in claim 3, characterized in that: The window (32) includes a first window (321) for installing the first set of window panels and a second window (322) for installing the second set of window panels. The first center line connecting the incident window and the exit window in the first window (321) and the second center line connecting the incident window and the exit window in the second window (322) are intersected. The intersection angle between the first center line and the second center line is 90°.

5. The membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy according to claim 1, characterized in that: The first group of optical window materials (31) is selected from one or more combinations of the following material groups: diamond, beryllium, polyimide, and ultra-thin glass; The second set of window materials of the optical window (31) is selected from one or more combinations of the following material groups: zinc selenide, calcium fluoride, potassium bromide, sodium chloride, magnesium fluoride, sapphire, quartz, and silicon.

6. The membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy according to claim 1, characterized in that: The cover assembly (30) includes a dome (33) in a hemispherical structure and fasteners (35) that seal the dome (33) onto the reaction platform (20) by means of a sealing ring (34). In the sealed and fastened state, the fastener (35) is sleeved on the outside of the dome (33) and fixed to the outer shell (10) by fastening bolts (36).

7. The membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy as described in claim 1, characterized in that... The reaction platform (20) includes a carrier plate (21) having an arc-shaped groove (22) and a side interface seat (23) thereon. The side interface seat (23) is aligned and arranged at both ends of the arc-shaped groove (22) for the passage and sealing of tubular samples.

8. The membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy according to claim 7, characterized in that... The lateral interface seat (23) is sealed to the tubular sample inserted therein by a flexible sealing structure. The flexible sealing structure includes a flexible pressure ring (24) sleeved on the tubular sample and a ferrule nut (25) that seals and presses the flexible pressure ring (24) tightly onto the tubular sample. The flexible pressure ring (24) is selected from graphite rings, fluororubber rings, perfluoroether rubber rings or metal C-rings.

9. The membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multimode spectroscopy as described in claim 7, characterized in that... The lower part of the support plate (21) is provided with a support column (26) that can be inserted and cooperated with the heating rod (27) and the thermocouple (28). The support column (26) has a central flow channel (29) that is connected from the air outlet pipe (50) to the arc-shaped groove (22). The end of the thermocouple (28) extends into the arc-shaped groove (22) through the central flow channel (29) to abut against the pipe sample.

10. The membrane catalytic in-situ reaction cell based on X-ray absorption spectroscopy and multi-mode spectroscopy according to claim 1, characterized in that... The outer shell (10) is provided with a circulating cooling water channel (11) surrounding the outside of the reaction platform (20). The materials of the outer shell (10) and the reaction platform (20) are selected from high-temperature and corrosion-resistant alloys, including but not limited to 316 stainless steel, 304 stainless steel, Hastelloy, Inconel, or titanium alloy.

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