A multiphase reaction analysis system and method combining in-situ multispectroscopy and mass spectrometry

Abstract

The present invention discloses a multiphase reaction analysis system and method combining in-situ multispectroscopy and mass spectrometry, belonging to the technical field of in-situ monitoring of multiphase reactions. The system comprises a control system, a reaction system, and a detection system. The reaction system comprises a modular plasma in-situ reactor and a DBD discharge device, and a liftable platform is provided below the reaction system. The detection system comprises synchronous in-situ emission spectroscopy detection, Fourier transform infrared spectroscopy detection, and infrared thermal imaging temperature detection. The present invention adopts the above-mentioned multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry. The provided reaction cell and discharge device are simple to operate and can simultaneously and dynamically detect data such as solid-phase surface groups, gas-phase active substances, and steady-state product types and change trends. This has important application value for analyzing the mechanisms of multiphase reactions driven by discharge or heating.

Description

Technical Field

[0001] The present invention relates to the technical field of multiphase reaction monitoring, and in particular to a multiphase reaction analysis system and method combining in-situ multispectroscopy and mass spectrometry. Background Art

[0002] Plasma catalysis utilizes the electron and ion flows in a plasma to increase the activity of a reaction process, thereby controllably increasing the reaction rate. The emergence of this technology offers new possibilities for chemical manufacturing, particularly in environmental management and energy conversion. The key concept of plasma catalysis is to enhance the reaction rate and make it more efficient by increasing the electron and ion flows in the reaction medium and reducing the amount of heat required for the reaction. Plasma catalysis can effectively improve the activity of reactions, allowing them to proceed at low temperatures, thereby reducing energy consumption. The interaction between the plasma and the catalyst can achieve a synergistic effect, further enhancing the catalytic effect. A major drawback of non-thermal plasma processes is their non-selectivity, leading to the formation of undesirable reaction byproducts. The mechanism of synergistic action between low-temperature plasma and catalysis remains unclear, particularly the molecular dynamics underlying the degradation of volatile organic compounds by plasma, which requires further investigation.

[0003] Heterogeneous catalysis is one of the most important processes in chemistry and chemical engineering, encompassing the majority of catalytic reactions used in industry. These reactions occur on the catalyst surface and involve processes such as the diffusion of reactant molecules within the catalyst pores, adsorption on the surface, reactions on the surface, and desorption of product molecules. In situ dynamic spectroscopy is a key technique in heterogeneous catalysis research, enabling real-time monitoring of catalyst surface changes under conditions close to those encountered in actual reactions. For years, scientists worldwide have explored various approaches, employing in situ analyzers such as infrared, Raman, electron microscopy, and nuclear magnetic resonance (NMR) on a variety of analytical instruments to capture transition states and intermediates in heterogeneous catalytic reactions, investigate reaction mechanisms, and ultimately uncover the "black box" of the reaction process. However, due to the complexity of heterogeneous catalytic reactions, only limited details of these processes have been understood.

[0004] Fourier transform infrared spectroscopy (FTIR) is widely used in mechanistic research, performance characterization, and compositional analysis due to its fast scanning speed, high resolution, and sensitivity. This is crucial for capturing subtle changes in heterogeneous catalytic reactions. FTIR spectrometers can monitor changes on catalyst surfaces in real time, including the identification of adsorbed intermediates and characterization of the catalyst surface itself. However, using FTIR spectrometers for in situ plasma heterogeneous catalysis in real-time requires high requirements for the reaction cell and discharge device, requiring further research and design.

[0005] Emission spectroscopy is a method for inferring the composition and properties of a sample by measuring the wavelength and intensity of light emitted by the sample after it is excited by energy. This technique is commonly used in fields such as elemental analysis, chemical reaction kinetics, and materials characterization. Emission spectroscopy allows for rapid analysis of the elements in a sample. Different elements have distinct spectral characteristics, so measuring the spectrum can determine the element type and content in the sample. Emission spectroscopy can also be used to study the rate and kinetic behavior of chemical reactions. During a reaction, the spectral characteristics of reactants and products change. By monitoring the evolution of the spectrum over time, information such as reaction rate and activation energy can be obtained.

[0006] Continuous mass spectrometry is an advanced analytical technique that combines the high sensitivity and selectivity of mass spectrometry with the capabilities of continuous automated detection. It is widely used in chemistry, biology, and environmental fields. The core of continuous mass spectrometry lies in ionizing compounds in a sample into ions, accelerating and separating them using electric or magnetic fields, and ultimately detecting and analyzing the ions based on their mass-to-charge ratio (m / z). The composition and structure of the sample can be determined by generating a mass spectrum that is analyzed and interpreted using advanced data processing systems.

[0007] Existing in-situ analytical techniques (such as in-situ infrared, Raman, electron microscopy, etc.) mostly rely on a single detection method, making it difficult to simultaneously capture the dynamic evolution of gas-phase free radicals, intermediate substances on the solid surface, and real-time changes in reaction products. For example, although Fourier transform infrared spectrometers can monitor surface adsorbed species, they lack synchronous analysis of gas-phase free radicals; emission spectroscopy can track free radicals, but cannot correlate with surface reaction mechanisms. Data fragmentation leads to incomplete analysis of multiphase reaction mechanisms. When integrating spectral detection, traditional plasma catalytic reaction cells have high compatibility requirements for discharge devices and temperature control systems, making it difficult to achieve modular design. Existing systems lack operational flexibility under variable temperature and power conditions, which limits the study of the mechanism of synergistic effects between plasma and catalysis. Existing systems often separate mass spectrometry detection from spectral analysis, making it impossible to achieve real-time online monitoring of reaction products and synchronous correlation of dynamic spectral data, making it difficult to fully reveal the evolution of reaction paths. The non-selective characteristics of non-thermal plasmas lead to the generation of by-products, but existing technologies make it difficult to simultaneously track gas-phase free radicals (such as OH, O) and surface intermediate substances (such as adsorbed C ), which restricts the in-depth understanding of the plasma-catalysis synergistic mechanism. Summary of the Invention

[0008] The object of the present invention is to provide a multiphase reaction analysis system and method combining in-situ multispectroscopy and mass spectrometry to solve the problems mentioned in the background technology.

[0009] To achieve the above-mentioned objectives, the present invention provides a multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry, comprising a control system, a reaction system and a detection system. The control system comprises a gas cylinder and a flow meter, and both the gas cylinder and the flow meter are provided in multiple numbers. The gas cylinder is connected to the flow meter, and the other end of the flow meter is connected to the reaction system through a drying tube. The reaction system comprises a plasma in-situ reactor and a DBD discharger, and a liftable platform is provided below the reaction system.

[0010] Preferably, the control system further includes a plasma generator, a modulator and an oscilloscope, the modulator and the oscilloscope are both connected to the plasma generator, and the plasma generator is connected to the reaction system.

[0011] Preferably, the plasma in-situ reactor includes a threaded end cover, a potassium bromide window, a pagoda head air inlet, an electric heating furnace, a high-voltage electric wire ceramic tube, a catalyst window, a pagoda head air outlet, a low-voltage electric wire ceramic tube, a threaded plunger and a quartz reactor. A placement cavity is provided inside the electric heating furnace, the catalyst window is provided in the placement cavity, the threaded plunger is provided above the catalyst window, the quartz reactor is symmetrically provided on both sides of the catalyst window, the other end of the quartz reactor passes through the electric heating furnace and is connected to the threaded end cover, the potassium bromide window is provided between the quartz reactor and the threaded end cover, the pagoda head air inlet and the pagoda head air outlet are respectively provided on the two quartz reactors, one end of the high-voltage electric wire ceramic tube and the low-voltage electric wire ceramic tube are both provided inside the placement cavity, and the other end of the high-voltage electric wire ceramic tube and the low-voltage electric wire ceramic tube both pass through the electric heating furnace.

[0012] Preferably, the catalyst window comprises a catalyst glass slide and a cover, wherein the cover is arranged on one side of the catalyst glass slide, and a circular groove is arranged on the catalyst glass slide.

[0013] Preferably, the DBD discharger is arranged inside the placement cavity, and the DBD discharger includes a ceramic stud, an upper ceramic shell, a high-voltage electrode plate, a ceramic sheet, a low-voltage electrode plate and a lower ceramic shell. The high-voltage electrode plate is arranged above the catalyst window, and the low-voltage electrode plate is arranged below the catalyst window. The ceramic sheets are respectively arranged on one side of the high-voltage electrode plate and the low-voltage electrode plate close to the catalyst window. The upper ceramic shell is arranged above the high-voltage electrode plate, and the lower ceramic shell is arranged below the low-voltage electrode plate. The upper ceramic shell and the lower ceramic shell are connected by the ceramic stud, and the middle of the ceramic stud passes through the quartz reactor.

[0014] Preferably, high-voltage wires and low-voltage wires are respectively arranged inside the high-voltage wire ceramic tube and the low-voltage wire ceramic tube, and the high-voltage wires and the low-voltage wires are respectively connected to the high and low voltage output ends of the plasma in-situ reactor, and the other ends of the high-voltage wires and the low-voltage wires pass through the high-voltage wire ceramic tube and the low-voltage wire ceramic tube and are respectively connected to the high-voltage electrode plate and the low-voltage electrode plate.

[0015] Preferably, the detection system includes an emission spectrometer, a Fourier transform infrared spectrometer, a handheld thermal imager, a mass spectrometer and a computer, and the emission spectrometer, the Fourier transform infrared spectrometer, the handheld thermal imager and the mass spectrometer are all connected to the computer.

[0016] Preferably, the plasma in-situ reactor and the DBD discharger are placed in the sample chamber of the Fourier transform infrared spectrometer via a liftable platform, and the optical probe of the emission spectrometer is fixed at the front end of the catalyst window.

[0017] Preferably, the other end of the pagoda head gas outlet is connected to a gas pipeline, the other end of the gas pipeline is connected to the mass spectrometer, and a drying tube 2 is provided on the gas pipeline.

[0018] The present invention provides a multiphase reaction analysis method combining in-situ multispectroscopy and mass spectrometry, the specific steps of which are as follows:

[0019] The catalyst pressed by the tablet pressing mold is placed in the catalyst window, the potassium bromide window is placed in the threaded end cap, the potassium bromide window is connected to the quartz reactor via a thread, the threaded plunger is connected to the quartz reactor, the DBD discharger is connected with a ceramic stud, and is tightly connected and fixed to the quartz reactor, the quartz reactor fixed with the DBD discharger is placed in an electric heating furnace, the electric heating furnace is placed on a liftable platform, and then placed in the sample chamber of the Fourier transform infrared spectrometer, and adjusted to a suitable height so that the Fourier transform infrared spectrometer can pass through the plasma in-situ reactor and detect a signal;

[0020] Connect the gas cylinder to the flow meter, lead the gas pipe from the flow meter to the pagoda head air inlet, connect the ground wire to the ground wire end of the plasma in-situ reactor, connect the high-voltage wire and the low-voltage wire to the high- and low-voltage output ends of the plasma in-situ reactor respectively, pass the other ends of the high-voltage wire and the low-voltage wire through the high- and low-voltage wire ceramic tubes and connect them to the high-voltage electrode plate and the low-voltage electrode plate respectively, and connect the oscilloscope signal channel and the modulator to the plasma generator;

[0021] Fix the optical probe of the emission spectrometer at the front end of the catalyst window, connect the emission spectrometer to the computer, connect the gas pipeline to the gas outlet of the pagoda head, connect the other end of the gas pipeline to the second phase of the drying tube, connect the dried gas to the mass spectrometer through the gas pipeline, and connect the mass spectrometer to the computer. Place a handheld thermal imager in front of the plasma in-situ reactor, and connect the other end to the computer;

[0022] After connecting the equipment, turn on the plasma generator, modulator, oscilloscope, Fourier transform infrared spectrometer, emission spectrometer, handheld thermal imager and mass spectrometer, open the gas cylinder, control the flow rate of different gases through the flow meter and introduce them into the plasma in-situ reactor;

[0023] The plasma in-situ reactor is introduced to start the reaction, and the flow meter flow rate and reaction temperature are changed according to the reaction conditions;

[0024] Use Fourier transform infrared spectrometer, emission spectrometer, online mass spectrometer and handheld thermal imager to achieve in-situ quantitative detection of gas phase free radicals and dynamic evolution information of intermediate substances on solid surface, and simultaneously measure reaction products and reaction zone temperature distribution online;

[0025] Turn off the plasma generator, turn off the power of the electric heating furnace, continue to introduce inert gas to cool to room temperature, and end the experiment;

[0026] Perform data analysis.

[0027] Therefore, the present invention adopts the above-mentioned multiphase reaction analysis system and method combining in-situ multispectroscopy and mass spectrometry, which has the following beneficial effects:

[0028] (1) The present invention provides an in-situ Fourier transform infrared spectroscopy reaction cell coupled with a modular DBD discharge device and a constant temperature device, which can perform plasma catalysis (or thermal catalysis) reactions under variable temperature and variable power;

[0029] (2) The design couples in-situ Fourier transform infrared spectroscopy, emission spectroscopy, online mass spectrometry, and temperature distribution detection units;

[0030] (3) Jointly realize in-situ quantitative detection of gas-phase free radicals and the dynamic evolution information of intermediate substances on the solid surface, and simultaneously measure the reaction products and the temperature distribution of the reaction zone online, thereby providing experimental support for the study of multiphase reaction mechanisms such as thermal catalysis, plasma catalysis, gasification, and combustion.

[0031] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1Schematic diagram of the structure of a multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry according to an embodiment of the present invention;

[0033] Figure 2 This is a schematic structural diagram of a plasma in-situ reactor according to an embodiment of the present invention;

[0034] Figure 3 It is the structural diagram of DBD discharger;

[0035] Figure 4 Schematic diagram of the structure of the catalyst window;

[0036] Figure 5 Schematic diagram of the structure of the threaded end cap and the quartz reactor;

[0037] Figure 6 In-situ infrared spectrum of Cu-Ni / γ-Al2O3 catalyst (not limited to this catalyst) surface material test changes over time;

[0038] Figure 7 This is the emission spectrum of the reaction between CO2 and H2 on Cu-Ni / γ-Al2O3 catalyst;

[0039] Figure 8 This is a continuous mass spectrum of the reaction of CO2 and H2 on Cu-Ni / γ-Al2O3 catalyst;

[0040] Figure 9 This is the macroscopic temperature diagram of the reaction of CO2 and H2 on Cu-Ni / γ-Al2O3 catalyst;

[0041] Reference numerals

[0042] X, control system; Y, reaction system; Z, detection system; 1, gas cylinder; 2, flow meter; 3, drying tube 1; 12, plasma generator; 13, modulator; 14, oscilloscope; 4, plasma in-situ reactor; 401, threaded end cap; 402, potassium bromide window; 403, pagoda head air inlet; 404, electric heating furnace; 405, high-voltage wire ceramic tube; 406, catalyst window; 4061, catalyst slide; 4062, cover; 4063, Circular groove; 407, pagoda head air outlet; 408, low-voltage electric wire ceramic tube; 409, threaded plunger; 410, quartz reactor; 5, DBD discharger; 501, ceramic stud; 502, upper ceramic shell; 503, high-voltage electrode plate; 504, ceramic sheet; 505, low-voltage electrode plate; 506, lower ceramic shell; 6, emission spectrometer; 7, Fourier transform infrared spectrometer; 8, computer; 9, handheld thermal imager; 10, mass spectrometer; 11, drying tube two. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0044] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0045] Example

[0046] like Figure 1-Figure 5 As shown, the present invention provides a multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry, including a control system X, a reaction system Y and a detection system Z.

[0047] The control system X includes a gas cylinder 1 and a flow meter 2. The gas cylinder 1 and the flow meter 2 are both provided in plurality. The gas cylinder 1 is connected to the flow meter 2. The other end of the flow meter 2 is connected to the reaction system Y through a drying tube 3.

[0048] The control system X further includes a plasma generator 12 , a modulator 13 and an oscilloscope 14 . The modulator 13 and the oscilloscope 14 are both connected to the plasma generator 12 , and the plasma generator 12 is connected to the reaction system Y.

[0049] The reaction system Y includes a plasma in-situ reactor 4 and a dielectric barrier discharger (DBD discharger 5 ), and a liftable platform is provided below the reaction system Y.

[0050] The plasma in-situ reactor 4 includes a threaded end cover 401, a potassium bromide window 402, a pagoda head air inlet 403, an electric heating furnace 404, a high-voltage wire ceramic tube 405, a catalyst window 406, a pagoda head air outlet 407, a low-voltage wire ceramic tube 408, a threaded plunger 409 and a quartz reactor 410. A placement cavity is provided inside the electric heating furnace 404, a catalyst window 406 is provided in the placement cavity, a threaded plunger 409 is provided above the catalyst window 406, the quartz reactor 410 is symmetrically provided on both sides of the catalyst window 406, and the other end of the quartz reactor 410 passes through the electric heating furnace 404 and is connected to the threaded end cover 401, the potassium bromide window 402 is provided between the quartz reactor 410 and the threaded end cover 401, the pagoda head air inlet 403 and the pagoda head air outlet 407 are respectively provided on the two quartz reactors 410, one end of the high-voltage wire ceramic tube 405 and the low-voltage wire ceramic tube 408 are both provided inside the placement cavity, and the other ends of the high-voltage wire ceramic tube 405 and the low-voltage wire ceramic tube 408 pass through the electric heating furnace 404.

[0051] Rubber gaskets are provided on both sides of the potassium bromide window 402, the gas pipe of the flowmeter 2 is connected to the pagoda head air inlet 403, the ground wire end of the plasma in-situ reactor 4 is connected to the ground wire, and high-voltage wire ceramic tube 405 and low-voltage wire ceramic tube 408 are respectively provided with high-voltage wires and low-voltage wires. The high-voltage wires and low-voltage wires are respectively connected to the high and low-voltage output ends of the plasma in-situ reactor 4, and the other ends of the high-voltage wires and low-voltage wires pass through the high-voltage wire ceramic tube 405 and the low-voltage wire ceramic tube 408 to be connected to the high-voltage electrode plate and the low-voltage electrode plate.

[0052] The catalyst window 406 includes a catalyst glass slide 4061 and a cover 4062 . The cover is provided on one side of the catalyst glass slide 4061 . A circular groove 4063 is provided on the catalyst glass slide 4061 . The catalyst is pressed and placed in the circular groove 4063 .

[0053] The DBD discharger 5 is disposed within the placement chamber and includes a ceramic stud 501, an upper ceramic housing 502, a high-voltage electrode plate 503, a ceramic sheet 504, a low-voltage electrode plate 505, and a lower ceramic housing 506. The high-voltage electrode plate 503 is disposed above the catalyst window 406, while the low-voltage electrode plate 505 is disposed below the catalyst window 406. The ceramic sheet 504 is disposed on one side of the high-voltage electrode plate 503 and the low-voltage electrode plate 505, respectively, near the catalyst window 406. The upper ceramic housing 502 is disposed above the high-voltage electrode plate 503, while the lower ceramic housing 506 is disposed below the low-voltage electrode plate 505. The upper and lower ceramic housings 502 and 506 are connected by a ceramic stud 501, which extends through the quartz reactor 410.

[0054] The detection system Z includes an emission spectrometer 6, a Fourier transform infrared spectrometer 7, a handheld thermal imager 9, a mass spectrometer 10 and a computer 8; the emission spectrometer 6, the Fourier transform infrared spectrometer 7, the handheld thermal imager 9, and the mass spectrometer 10 are all connected to the computer 8; the plasma in-situ reactor 4 and the DBD discharger 5 are placed in the sample chamber of the Fourier transform infrared spectrometer 7 via a liftable platform for detection, and the optical probe of the emission spectrometer 6 is fixed to the front end of the catalyst window 406.

[0055] The other end of the pagoda head gas outlet 407 is connected to a gas pipeline, and the other end of the gas pipeline is connected to the mass spectrometer 10. A drying tube 11 is provided on the gas pipeline.

[0056] The present invention provides a multiphase reaction analysis method combining in-situ multispectroscopy and mass spectrometry, the specific steps of which are as follows:

[0057] A. Place the catalyst pressed by the tableting mold into the catalyst window, place the potassium bromide window into the threaded end cap, place rubber gaskets on both sides of the potassium bromide window, connect the potassium bromide window to the quartz reactor via threads, connect the threaded plunger to the quartz reactor, seal with rubber gaskets, connect the DBD discharger with ceramic studs, and tightly connect and secure it to the quartz reactor. Place the quartz reactor fixed with the DBD discharger into an electric heating furnace, place the electric heating furnace on a liftable platform, and then place it in the sample chamber of a Fourier transform infrared spectrometer. Adjust the height appropriately so that the Fourier transform infrared spectrometer can pass through the plasma in-situ reactor and detect the signal.

[0058] B. Connect the gas cylinder to the flow meter, lead the gas pipe from the flow meter to the pagoda head air inlet, connect the ground wire to the ground terminal of the plasma in-situ reactor, connect the high-voltage wire and low-voltage wire to the high and low voltage output terminals of the plasma in-situ reactor respectively, and pass the other ends through the high and low voltage wire ceramic tubes to connect to the high-voltage electrode plate and low-voltage electrode plate respectively. Connect the oscilloscope signal channel and modulator to the plasma generator;

[0059] C. Fix the optical probe of the emission spectrometer at the front end of the catalyst window to detect the emission spectrum signal of the discharge area, and connect the emission spectrometer to a computer; connect a gas pipeline to the gas outlet of the pagoda head, connect the other end of the gas pipeline to the second phase of the drying tube, and connect the dried gas to the mass spectrometer through the gas pipeline. The mass spectrometer is connected to the computer to record the data and generate a mass spectrum; place a handheld thermal imager in front of the plasma in-situ reactor, and connect the other end of the handheld thermal imager to the computer to detect the macroscopic temperature of the plasma in-situ reactor;

[0060] D. After connecting the equipment, turn on the plasma generator, modulator, oscilloscope, Fourier transform infrared spectrometer, emission spectrometer, handheld thermal imager, and mass spectrometer. Open the gas cylinders and control the flow rates of different gases through flow meters and introduce them into the plasma in-situ reactor.

[0061] E. Introduce plasma into the in-situ reactor to start the reaction, and change the flow meter flow and reaction temperature according to the reaction conditions;

[0062] F. Use a Fourier transform infrared spectrometer, an emission spectrometer, an online mass spectrometer, and a handheld thermal imager to achieve in-situ quantitative detection of gas-phase free radicals and the dynamic evolution of intermediate substances on the solid surface, while also measuring the reaction products and the temperature distribution of the reaction zone online.

[0063] G. Turn off the plasma generator, turn off the power of the electric heating furnace, continue to pass inert gas to cool to room temperature, and end the experiment;

[0064] H. Perform data analysis. The specific steps include exporting data from a Fourier transform infrared spectrometer, plotting a Fourier transform infrared absorption spectrum, analyzing the intermediate substances on the surface of the solid catalyst based on the wavenumber range of different absorption peaks, and obtaining surface reaction details; exporting data from an emission spectrometer, plotting an emission spectrum, and analyzing the intermediate products of gas-phase free radicals based on the positions of different absorption peaks in the emission spectrum to obtain details of the gas-phase reaction process; using an online mass spectrometer to detect and analyze the real-time changes of various reaction products, thereby clarifying the plasma catalytic reaction process and reaction products; and using a handheld thermal imager to detect the temperature distribution in the reaction area.

[0065] In this embodiment, CO2 and H2 are used to conduct reaction studies on a Cu-Ni / γ-Al2O3 catalyst (not limited to this catalyst).

[0066] A Cu-Ni / γ-Al2O3 catalyst (not limited to this catalyst) pressed from a tableting mold was placed in a catalyst window, connected to an in-situ plasma reactor, and placed in the sample chamber of a Fourier transform infrared spectrometer. The height was adjusted to allow the Fourier transform infrared spectrometer to pass through the in-situ plasma reactor and detect the signal. The Fourier transform infrared spectrometer, emission spectrometer, mass spectrometer, and handheld thermal imager were connected to a computer. Gas cylinders were opened, flowmeters were connected, and the reaction gases (CO2 and H2) (1:3) were introduced. The plasma generator and oscilloscope were turned on, and the power was adjusted to initiate the reaction. The flow rate and reaction temperature were adjusted according to the reaction conditions. Infrared data were collected in situ using the Fourier transform infrared spectrometer, intermediate and product data were collected using the emission spectrometer and mass spectrometer, and the macroscopic temperature of the in-situ plasma reactor was captured using a handheld thermal imager during the reaction.

[0067] Reference Figure 6 , wave number 3735 cm-1 and 3704 cm -1 These two peaks are located in the higher wavenumber region, typically associated with OH stretching vibrations, and may correspond to the stretching vibration modes of surface hydroxyl groups (-OH). On the catalyst surface, these hydroxyl groups may be caused by hydroxyl groups in the alumina support or other components, or by OH stretching vibrations in adsorbed water molecules generated during the reaction. 2173 cm -1 and 2117 cm -1 These two peaks may be related to the adsorbed CO, 2110~2180 cm -1 The peaks in the range are usually attributed to the stretching vibration of adsorbed CO. -1 and 1540 cm -1 The peak may correspond to carbonate (CO3 2- ) or formate (HCOO - ) asymmetric stretching vibration mode. 1340 cm -1 The peak may be related to formate (HCOO - ) is related to the symmetrical OCO vibration mode of the carbonate, or it may be a vibration mode of the adsorbed methoxy group (CH3O ) of the CH bending vibration.

[0068] Reference Figure 7 The figure shows different substances corresponding to different wavelengths, including CO, CO2 + , CO2 and O and other intermediate products.

[0069] Reference Figure 8 The figure shows the change of partial pressure of Ar, CO2, H2 and CO over time under continuous mass spectrometry.

[0070] Reference Figure 9 ,The figure shows the macro temperature changes in the reactor discharge ,region and the surrounding areas.

[0071] Figures 6 to 8 It shows that the present invention can well realize the in-situ quantitative detection of gas-phase free radicals and the dynamic evolution information of intermediate substances on the solid surface, and at the same time measure the reaction products and the temperature distribution of the reaction zone online, thereby providing experimental support for the study of multiphase reaction mechanisms such as thermal catalysis, plasma catalysis, gasification, combustion, etc.

[0072] Therefore, the present invention adopts the above-mentioned combined in-situ multi-spectroscopy and mass spectrometry multiphase reaction analysis system and method, and provides an in-situ Fourier transform infrared spectroscopy reaction cell coupled with a modular DBD discharge device and a constant temperature device, which can perform plasma catalysis (or thermal catalysis) reactions under variable temperature and variable power.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry, characterized by: It includes a control system, a reaction system and a detection system. The control system includes a gas cylinder and a flow meter. The gas cylinder and the flow meter are both provided in multiple numbers. The gas cylinder is connected to the flow meter. The other end of the flow meter is connected to the reaction system through a drying tube. The reaction system includes a plasma in-situ reactor and a DBD discharger. A liftable platform is provided below the reaction system. The control system further comprises a plasma generator, a modulator and an oscilloscope, wherein the modulator and the oscilloscope are both connected to the plasma generator, and the plasma generator is connected to the reaction system; The plasma in-situ reactor includes a threaded end cap, a potassium bromide window, a pagoda head air inlet, an electric heating furnace, a high-voltage electric wire ceramic tube, a catalyst window, a pagoda head air outlet, a low-voltage electric wire ceramic tube, a threaded plunger and a quartz reactor. The electric heating furnace is provided with a placement cavity, the catalyst window is provided in the placement cavity, the threaded plunger is provided above the catalyst window, the quartz reactor is symmetrically provided on both sides of the catalyst window, the other end of the quartz reactor passes through the electric heating furnace and is connected to the threaded end cap, the potassium bromide window is provided between the quartz reactor and the threaded end cap, the pagoda head air inlet and the pagoda head air outlet are respectively provided on the two quartz reactors, one end of the high-voltage electric wire ceramic tube and the low-voltage electric wire ceramic tube are both provided inside the placement cavity, and the other end of the high-voltage electric wire ceramic tube and the low-voltage electric wire ceramic tube both pass through the electric heating furnace; The DBD discharger is arranged inside the placement cavity, and the DBD discharger includes a ceramic stud, an upper ceramic shell, a high-voltage electrode plate, a ceramic sheet, a low-voltage electrode plate and a lower ceramic shell. The high-voltage electrode plate is arranged above the catalyst window, and the low-voltage electrode plate is arranged below the catalyst window. The ceramic sheets are respectively arranged on one side of the high-voltage electrode plate and the low-voltage electrode plate close to the catalyst window. The upper ceramic shell is arranged above the high-voltage electrode plate, and the lower ceramic shell is arranged below the low-voltage electrode plate. The upper ceramic shell and the lower ceramic shell are connected by the ceramic stud, and the middle of the ceramic stud passes through the quartz reactor.

2. The multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry according to claim 1, characterized in that: The catalyst window comprises a catalyst glass slide and a cover, wherein the cover is arranged on one side of the catalyst glass slide, and a circular groove is arranged on the catalyst glass slide.

3. The multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry according to claim 2, characterized in that: High-voltage wires and low-voltage wires are respectively arranged inside the high-voltage wire ceramic tube and the low-voltage wire ceramic tube. The high-voltage wires and the low-voltage wires are respectively connected to the high and low voltage output ends of the plasma in-situ reactor. The other ends of the high-voltage wires and the low-voltage wires pass through the high-voltage wire ceramic tube and the low-voltage wire ceramic tube and are respectively connected to the high-voltage electrode plate and the low-voltage electrode plate.

4. The multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry according to claim 3, characterized in that: The detection system includes an emission spectrometer, a Fourier transform infrared spectrometer, a handheld thermal imager, a mass spectrometer and a computer. The emission spectrometer, the Fourier transform infrared spectrometer, the handheld thermal imager and the mass spectrometer are all connected to the computer.

5. The multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry according to claim 4, characterized in that: The plasma in-situ reactor and the DBD discharger are placed in the sample chamber of the Fourier transform infrared spectrometer via a liftable platform, and the optical probe of the emission spectrometer is fixed on the front end of the catalyst window.

6. The multiphase reaction analysis system combining in-situ multispectroscopy and mass spectrometry according to claim 5, characterized in that: The other end of the pagoda head gas outlet is connected to a gas pipeline, the other end of the gas pipeline is connected to the mass spectrometer, and a drying tube 2 is provided on the gas pipeline.

7. A method for multiphase reaction analysis using a combined in-situ multispectroscopy and mass spectrometry method, applied to a multiphase reaction analysis system using a combined in-situ multispectroscopy and mass spectrometry method according to any one of claims 1 to 6, characterized in that: The specific steps are as follows: Install the multiphase reaction analysis system and turn on the plasma in-situ generator, modulator, oscilloscope, Fourier transform infrared spectrometer, emission spectrometer, handheld thermal imager, and mass spectrometer; Open the gas cylinder, control the flow rate of different gases through the flow meter and introduce them into the plasma in-situ reactor, and change the flow meter flow rate and reaction temperature according to the reaction conditions; Use Fourier transform infrared spectrometer, emission spectrometer, online mass spectrometer and handheld thermal imager to achieve in-situ quantitative detection of gas phase free radicals and dynamic evolution of intermediate substances on solid surface, and simultaneously measure reaction products and reaction zone temperature distribution online; Turn off the power of the plasma generator and the electric heating furnace, continue to introduce inert gas and cool to room temperature, and end the experiment; Perform data analysis.

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