Multiphase reaction analysis system and method combining in-situ multispectrum and mass spectrum

Abstract

The invention discloses a multiphase reaction analysis system and method combining in-situ multispectrum and mass spectrometry, and belongs to the technical field of multiphase reaction in-situ monitoring, the multiphase reaction analysis 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, a liftable platform is arranged below the reaction system; the detection system comprises synchronous in-situ emission spectrum detection, Fourier infrared spectrum detection and infrared thermography temperature detection. According to the multiphase reaction analysis system combining the in-situ multispectrum and the mass spectrum, provided by the invention, the reaction tank and the discharge device are simple to operate, and data such as types and variation trends of solid-phase surface groups, gas-phase active substances and steady-state products can be synchronously and dynamically detected; the method has an important application value in analysis of a discharge or heating driven multiphase reaction mechanism.

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 multi-spectroscopy and mass spectrometry. Background Art

[0002] Plasma catalysis technology utilizes the electron flow and ion flow in the plasma to increase the activity of the reaction process, enabling the reaction rate to be controllably increased. The emergence of this technology provides a new possibility for chemical manufacturing, especially in environmental governance and energy conversion. The main idea of plasma catalysis is to enhance the reaction rate by increasing the electron flow and ion flow in the reaction medium and reducing the heating amount required for the reaction, making the reaction more efficient. Plasma catalysis technology can effectively improve the activity of the reaction, enabling the reaction to proceed at low temperatures, thereby reducing energy consumption. The interaction between the plasma and the catalyst can achieve a synergistic effect, further improving the catalytic effect. One of the main disadvantages in the non-thermal plasma process is the non-selectivity of the process, resulting in the formation of undesired reaction by-products. The mechanism of the synergistic effect between low-temperature plasma and catalysis is not clear, especially the basic molecular dynamics theory of plasma degradation of volatile organic compounds remains to be further studied.

[0003] Heterogeneous catalysis is one of the most important processes in the field of chemistry and chemical engineering, and most of the catalytic reactions used in industry belong to heterogeneous catalysis. Such reactions occur on the surface of the catalyst and include processes such as the diffusion of reactant molecules in the catalyst pores, adsorption on the surface, reaction on the surface, and desorption of product molecules. In-situ dynamic spectroscopy research is an important technique in heterogeneous catalysis research, which can real-time monitor the changes on the catalyst surface under near-actual reaction conditions. Over the years, scientists around the world have tried various methods and attempted to use some in-situ analyzers on various analytical instruments, such as in-situ infrared, in-situ Raman, in-situ electron microscopy, in-situ nuclear magnetic resonance, etc. to capture the transition states and intermediate states of heterogeneous catalytic reactions, study the reaction mechanism, in order to uncover the "black box" in the reaction process. However, due to the complexity of the heterogeneous catalytic reaction process, people only understand some details of the heterogeneous catalytic reaction process in some aspects.

[0004] Fourier transform infrared spectroscopy analysis technology is widely used in fields such as mechanism research, performance characterization, and component detection due to its fast scanning speed, high resolution, and high sensitivity. This is crucial for capturing the subtle changes in heterogeneous catalytic reactions. Fourier transform infrared spectrometers can real-time monitor the changes on the catalyst surface, including the identification of adsorbed intermediates and the characterization of the catalyst surface itself. However, the in-situ plasma heterogeneous catalysis real-time detection using Fourier transform infrared spectrometers has high requirements for the reaction cell and discharger, and further research and design are needed.

[0005] Emission spectroscopy analysis technology is a method based on measuring the wavelength and intensity of the light emitted by a sample after being excited by energy to infer the composition and properties of the sample. This technology is commonly used in fields such as elemental analysis, research on chemical reaction kinetics, and material characterization. By using emission spectroscopy, rapid analysis of elements in a sample can be carried out. Different elements have different spectral characteristics, so the types and contents of elements in the sample can be determined by measuring the spectrogram. Emission spectroscopy can also be used to study the rate and kinetic behavior of chemical reactions. In a reaction, the spectral characteristics of reactants and products will 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 detection technology is an advanced analysis technology that combines the high sensitivity, high selectivity of mass spectrometry technology and the ability of continuous automated detection, and is widely used in fields such as chemistry, biology, and environment. The core of continuous mass spectrometry detection technology is to ionize the compounds in the sample into ions, accelerate and separate them through an electric field or magnetic field, and finally detect and analyze them according to the mass-to-charge ratio (m / z) of the ions. By generating a mass spectrogram and analyzing and interpreting it through an advanced data processing system, the composition and structure of the sample can be determined.

[0007] Existing in-situ analysis technologies (such as in-situ infrared, Raman, electron microscopy, etc.) mostly rely on single detection means and are difficult to simultaneously capture the dynamic evolution of gas-phase free radicals, solid surface intermediate substances, and the real-time changes of reaction products. For example, although a Fourier transform infrared spectrometer can monitor surface-adsorbed species, it lacks synchronous analysis of gas-phase free radicals; emission spectroscopy can trace free radicals but cannot correlate with the surface reaction mechanism. Data fragmentation leads to incomplete analysis of the multiphase reaction mechanism. When integrating spectral detection in a traditional plasma catalytic reaction cell, the compatibility requirements for the discharge device and temperature control system are high, and it is difficult to achieve modular design. The existing systems have insufficient operational flexibility under variable temperature and variable power conditions, which limits the research on the mechanism of the synergy between plasma and catalysis. Existing systems often separate mass spectrometry detection from spectral analysis, unable to achieve real-time online monitoring of reaction products and synchronous correlation of dynamic spectral data, and it is difficult to comprehensively reveal the evolution of the reaction path. The non-selective characteristics of non-thermal plasma lead to the generation of by-products, but existing technologies are difficult to simultaneously track gas-phase free radicals (such as OH, O) and surface intermediate substances (such as adsorbed CO2 - )), which restricts the in-depth understanding of the plasma-catalysis synergy mechanism. Summary of the Invention

[0008] The purpose of the present invention is to provide a multiphase reaction analysis system and method that combines in-situ multi-spectroscopy and mass spectrometry to solve the problems mentioned in the background technology.

[0009] To achieve the above object, the present invention provides a multiphase reaction analysis system combining in-situ multispectral and mass spectrometry, including a control system, a reaction system and a detection system. The control system includes gas cylinders and flow meters. A plurality of gas cylinders and flow meters are provided. The gas cylinders are connected to the flow meters. The other end of the flow meter is connected to the reaction system through a first drying tube. The reaction system includes a plasma in-situ reactor and a DBD discharger. 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. The plasma generator is connected to the reaction system.

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

[0012] Preferably, the catalyst window includes a catalyst glass slide and a cover. The cover is arranged on one side of the catalyst glass slide. A circular groove is provided on the catalyst glass slide.

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

[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. The high-voltage wire and the low-voltage wire are respectively connected to the high-voltage and low-voltage output ends of the plasma in-situ reactor. The other ends of the high-voltage wire and the low-voltage wire 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. 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 through a lift platform. The optical probe of the emission spectrometer is fixed at the front end of the catalyst window.

[0017] Preferably, the other end of the outlet of the pagoda head is connected to a gas transmission pipeline. The other end of the gas transmission pipeline is connected to the mass spectrometer. A second drying tube is arranged on the gas transmission pipeline.

[0018] The present invention provides a multiphase reaction analysis method combining in-situ multi-spectroscopy and mass spectrometry. The specific steps are as follows: Place the catalyst pressed by the tablet press mold in the catalyst window. Place the potassium bromide window in the threaded end cap. The potassium bromide window is connected to the quartz reactor by threads. The threaded plunger is connected to the quartz reactor. Connect the DBD discharger with a ceramic stud and tightly connect and fix it to the quartz reactor. Place the quartz reactor fixed to the DBD discharger in the electric heating furnace. Place the electric heating furnace on the lift platform and place it in the sample chamber of the Fourier transform infrared spectrometer. Adjust to a suitable height so that the Fourier transform infrared spectrometer can pass through the plasma in-situ reactor and detect signals. Connect the gas cylinder to the flowmeter. Lead the gas transmission pipe from the flowmeter and connect it to the inlet of the pagoda head. 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-voltage and low-voltage output ends of the plasma in-situ reactor respectively. The other ends of the high-voltage wire and the low-voltage wire pass through the high- and low-voltage wire ceramic tubes and are respectively connected to the high-voltage electrode plate and the low-voltage electrode plate. Connect the signal channel of the oscilloscope and the modulator to the plasma generator. 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; 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; 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; 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; 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; Perform data analysis.

[0019] 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: (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; (2) The design couples in-situ Fourier transform infrared spectroscopy, emission spectroscopy, online mass spectrometry, and temperature distribution detection units; (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.

[0020] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic 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; Figure 2 This is a schematic structural diagram of a plasma in-situ reactor according to an embodiment of the present invention; Figure 3 It is the structural diagram of DBD discharger; Figure 4 It is a schematic structural diagram of the catalyst window pane; Figure 5 It is a schematic structural diagram of the threaded end cap and the quartz reactor; Figure 6 It is an in-situ infrared spectrogram showing the change of the surface substances of the Cu-Ni / γ-Al2O3 catalyst (not limited to this catalyst) over time; Figure 7 It is an emission spectrogram of the reaction of CO2 and H2 on the Cu-Ni / γ-Al2O3 catalyst; Figure 8 It is a continuous mass spectrogram of the reaction of CO2 and H2 on the Cu-Ni / γ-Al2O3 catalyst; Figure 9 It is a macroscopic temperature diagram of the reaction of CO2 and H2 on the Cu-Ni / γ-Al2O3 catalyst; Reference numerals 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 pane; 403, pagoda head air inlet; 404, electric heating furnace; 405, high-voltage wire ceramic tube; 406, catalyst window pane; 4061, catalyst slide; 4062, seal cover; 4063, circular groove; 407, pagoda head air outlet; 408, low-voltage wire ceramic tube; 409, threaded plunger; 410, quartz reactor; 5, DBD discharger; 501, ceramic stud; 502, upper ceramic housing; 503, high-voltage electrode plate; 504, ceramic sheet; 505, low-voltage electrode plate; 506, lower ceramic housing; 6, emission spectrometer; 7, Fourier transform infrared spectrometer; 8, computer; 9, handheld thermal imager; 10, mass spectrometer; 11, drying tube 2. Specific embodiments

[0022] To make the objectives, 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 accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

[0023] It should be noted that like reference numerals and letters refer to like items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] Embodiment As Figures 1 - 5 shown, the present invention provides a multiphase reaction analysis system integrating in-situ multispectral and mass spectrometry, including a control system X, a reaction system Y, and a detection system Z.

[0025] The control system X includes gas cylinders 1 and flow meters 2. A plurality of gas cylinders 1 and flow meters 2 are provided. The gas cylinders 1 are connected to the flow meters 2, and the other end of the flow meter 2 is connected to the reaction system Y through a first drying tube 3.

[0026] 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.

[0027] The reaction system Y includes a plasma in-situ reactor 4 and a DBD discharger 5. A liftable platform is provided below the reaction system Y.

[0028] The plasma in-situ reactor 4 includes a threaded end cap 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. The catalyst window 406 is disposed in the placement cavity. The threaded plunger 409 is disposed above the catalyst window 406. The quartz reactors 410 are symmetrically disposed on both sides of the catalyst window 406, and the other ends of the quartz reactors 410 penetrate through the electric heating furnace 404 and are connected to the threaded end cap 401. The potassium bromide window 402 is disposed between the quartz reactor 410 and the threaded end cap 401. The pagoda head air inlet 403 and the pagoda head air outlet 407 are respectively disposed on the two quartz reactors 410. One ends of the high-voltage wire ceramic tube 405 and the low-voltage wire ceramic tube 408 are both disposed inside the placement cavity, and the other ends of the high-voltage wire ceramic tube 405 and the low-voltage wire ceramic tube 408 penetrate through the electric heating furnace 404.

[0029] Both sides of the potassium bromide window 402 are provided with rubber gaskets. The gas delivery pipe of the flowmeter 2 is connected to the inlet of the taper head 403. The ground wire end of the plasma in-situ reactor 4 is connected to the ground wire. High-voltage wires and low-voltage wires are respectively arranged inside the high-voltage wire ceramic tube 405 and the low-voltage wire ceramic tube 408. The high-voltage wire and the low-voltage wire are respectively connected to the high-voltage and low-voltage output ends of the plasma in-situ reactor 4. The other ends of the high-voltage wire and the low-voltage wire respectively pass through the high-voltage wire ceramic tube 405 and the low-voltage wire ceramic tube 408 and are connected to the high-voltage electrode plate and the low-voltage electrode plate.

[0030] The catalyst window 406 includes a catalyst glass slide 4061 and a cover 4062. The cover is arranged on one side of the catalyst glass slide 4061. A circular groove 4063 is arranged on the catalyst glass slide 4061. After the catalyst is tableted, it is arranged in the circular groove 4063.

[0031] The DBD discharger 5 is arranged inside the placement cavity. The DBD discharger 5 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 arranged above the catalyst window 406. The low-voltage electrode plate 505 is arranged below the catalyst window 406. The ceramic sheet 504 is respectively arranged on one side of the high-voltage electrode plate 503 and the low-voltage electrode plate 505 close to the catalyst window 406. The upper ceramic housing 502 is arranged above the high-voltage electrode plate 503. The lower ceramic housing 506 is arranged below the low-voltage electrode plate 505. The upper ceramic housing 502 and the lower ceramic housing 506 are connected by the ceramic stud 501, and the quartz reactor 410 passes through the middle of the ceramic stud 501.

[0032] 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 through a liftable platform for detection. The optical probe of the emission spectrometer 6 is fixed at the front end of the catalyst window 406.

[0033] The other end of the taper head outlet 407 is connected to a gas delivery pipe. The other end of the gas delivery pipe is connected to the mass spectrometer 10. A second drying tube 11 is arranged on the gas delivery pipe.

[0034] The present invention provides a multiphase reaction analysis method combining in-situ multi-spectroscopy and mass spectrometry. The specific steps are as follows: 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. 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; 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; 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. 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; 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. 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; H. Conduct 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 ranges of different absorption peaks to obtain details of the surface reaction; exporting data from an emission spectrometer, plotting an emission spectrum, and analyzing gas-phase radical intermediate products based on the positions of different absorption peaks in the emission spectrum to obtain details of the gas-phase reaction process; detecting with an on-line mass spectrometer to analyze the real-time changes of various reaction products, thereby clarifying the plasma catalytic reaction process and reaction products; detecting the temperature distribution in the reaction zone with a hand-held thermal imager.

[0035] In this embodiment, the reaction of CO2 and H2 on a Cu-Ni / γ-Al2O3 catalyst (not limited to this catalyst) is studied.

[0036] Place the pressed Cu-Ni / γ-Al2O3 catalyst (not limited to this catalyst) in the catalyst window, connect the in-situ plasma reactor, and place it in the sample chamber of the Fourier transform infrared spectrometer. Adjust the appropriate height so that the Fourier transform infrared spectrometer can pass through the in-situ plasma reactor and detect signals. Connect the Fourier transform infrared spectrometer, emission spectrometer, mass spectrometer, and hand-held thermal imager to a computer. Open the gas cylinder, connect the flowmeter, and introduce the reaction gases CO2 and H2 (1:3). Turn on the plasma generator and oscilloscope, and adjust the appropriate power to start the reaction. Change the flow rate of the flowmeter and the reaction temperature according to the reaction conditions; in-situ collect infrared data with the Fourier transform infrared spectrometer, collect intermediate product and product data with the emission spectrometer and mass spectrometer, and collect the macroscopic temperature of the in-situ plasma reactor during the reaction process with the hand-held thermal imager.

[0037] Refer to Figure 6 , the two peaks at wavenumbers 3735 cm -1 and 3704 cm -1 are located in the higher wavenumber region and are usually related to the O-H stretching vibration, and may correspond to the stretching vibration mode 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 the O-H stretching vibration of adsorbed water molecules generated during the reaction. The two peaks at 2173 cm -1 and 2117 cm -1 may be related to adsorbed CO, and the peaks in the range of 2110 - 2180 cm -1 are usually attributed to the stretching vibration of adsorbed CO. The peaks at 1579 cm -1 and 1540 cm -1 may correspond to carbonate (CO3 2- ) or formate (HCOO -)asymmetric stretching vibration mode. 1340 cm -1 The peak at may be related to the symmetric O-C-O vibration mode of formate (HCOO - ), or a certain vibration mode of carbonate, or the C-H bending vibration of adsorbed methoxy .

[0038] Refer to Figure 7 , the figure shows different substances corresponding to different wavelengths, including intermediate products such as CO, CO2 + and O.

[0039] Refer to Figure 8 , the figure shows the variation of the mass fractions of products such as CO2, H2, CO, CH4 and O2 with time under continuous mass spectrometry.

[0040] Refer to Figure 9 , the figure shows the macroscopic temperature change in the discharge area and the surrounding area of the reactor.

[0041] Figures 6 - 8 It shows that the present invention can well realize in-situ quantitative detection of gas-phase free radicals and dynamic evolution information of intermediate substances on the solid surface, and simultaneously online measure the reaction products and the temperature distribution in the reaction zone, thereby providing experimental support for studying the reaction mechanisms of heterogeneous reactions such as thermal catalysis, plasma catalysis, gasification, combustion, etc.

[0042] Therefore, the present invention adopts the above-mentioned heterogeneous reaction analysis system and method combining in-situ multi-spectroscopy and mass spectrometry, 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.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions of the present invention or make equivalent substitutions, and these modifications or equivalent substitutions cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A multiphase reaction analysis system integrating in-situ multi-spectral and mass spectrometry, characterized in that: It includes a control system, a reaction system and a detection system. The control system includes gas cylinders and flow meters. A number of gas cylinders and flow meters are provided. The gas cylinders are connected to the flow meters. The other end of the flow meter is connected to the reaction system through a first drying tube. The reaction system includes a plasma in-situ reactor and a DBD discharger. A liftable platform is arranged below the reaction system.

2. The multiphase reaction analysis system combining in-situ multispectral and mass spectrometry according to claim 1, wherein: 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. The plasma generator is connected to the reaction system.

3. The multiphase reaction analysis system combining in-situ hyperspectral and mass spectrometry according to claim 2, wherein: 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 wire ceramic tube, a catalyst window, a pagoda head air outlet, a low-voltage wire ceramic tube, a threaded plunger and a quartz reactor. A placement cavity is arranged inside the electric heating furnace. The catalyst window is arranged in the placement cavity. The threaded plunger is arranged above the catalyst window. The quartz reactors are symmetrically arranged on both sides of the catalyst window. The other ends of the quartz reactors penetrate through the electric heating furnace and are connected to the threaded end cap. The potassium bromide window is arranged between the quartz reactor and the threaded end cap. The pagoda head air inlet and the pagoda head air outlet are respectively arranged on the two quartz reactors. One ends of the high-voltage wire ceramic tube and the low-voltage wire ceramic tube are both arranged inside the placement cavity. The other ends of the high-voltage wire ceramic tube and the low-voltage wire ceramic tube penetrate through the electric heating furnace.

4. A multiphase reaction analysis system combining in-situ hyperspectral and mass spectrometry according to claim 3, characterized in that: The catalyst window includes a catalyst glass slide and a cover. The cover is arranged on one side of the catalyst glass slide. A circular groove is arranged on the catalyst glass slide.

5. A multiphase reaction analysis system combining in-situ multispectral and mass spectrometry according to claim 4, characterized in that: The DBD discharger is arranged inside the placement cavity. The DBD discharger includes a ceramic stud, an upper ceramic housing, a high-voltage electrode plate, a ceramic sheet, a low-voltage electrode plate and a lower ceramic housing. The high-voltage electrode plate is arranged above the catalyst window. The low-voltage electrode plate is arranged below the catalyst window. The ceramic sheets are respectively arranged on one sides of the high-voltage electrode plate and the low-voltage electrode plate close to the catalyst window. The upper ceramic housing is arranged above the high-voltage electrode plate. The lower ceramic housing is arranged below the low-voltage electrode plate. The upper ceramic housing and the lower ceramic housing are connected through the ceramic stud. And the ceramic stud penetrates through the quartz reactor in the middle.

6. The multiphase reaction analysis system combining in-situ multispectrum and mass spectrometry according to claim 5, 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 wire and the low-voltage wire are respectively connected to the high-voltage and low-voltage output ends of the plasma in-situ reactor. The other ends of the high-voltage wire and the low-voltage wire 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.

7. A multiphase reaction analysis system combining in-situ multispectral and mass spectrometry according to claim 6, 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.

8. A multiphase reaction analysis system combining in-situ multispectral and mass spectrometry according to claim 7, characterized in that: The plasma in-situ reactor and the DBD discharger are placed in the sample chamber of the Fourier transform infrared spectrometer through a liftable platform, and the optical probe of the emission spectrometer is fixed at the front end of the catalyst window.

9. A multiphase reaction analysis system combining in-situ multispectral and mass spectrometry according to claim 8, characterized in that: The other end of the outlet of the tower head is connected to a gas transmission pipeline, the other end of the gas transmission pipeline is connected to the mass spectrometer, and a second drying tube is provided on the gas transmission pipeline.

10. A multiphase reaction analysis method combining in-situ multispectral and mass spectrometry, applied to a multiphase reaction analysis system combining in-situ multispectral and mass spectrometry according to any one of claims 1-9, 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 rates of different gases through the flowmeter and introduce them into the plasma in-situ reactor, and change the flow rate of the flowmeter and the reaction temperature according to the reaction conditions; Use the Fourier transform infrared spectrometer, emission spectrometer, on-line mass spectrometer, and handheld thermal imager to realize in-situ quantitative detection of the dynamic evolution information of gas-phase free radicals and solid-surface intermediate substances, and simultaneously on-line measure the temperature distribution of reaction products and reaction zones; Turn off the power supplies of the plasma generator and the electric heating furnace, continue to introduce inert gas to cool to room temperature, and end the experiment; Conduct data analysis.

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