Double-pulse reaction device for researching catalytic reaction mechanism
By integrating a high-speed pulse valve and a vacuum microreactor into a dual-pulse reaction device, and combining a time-of-flight mass spectrometer with an adjustable energy electron bombardment ionization source and a single-photon ionization source, the problem of in-situ detection of catalytic reaction intermediates has been solved, enabling the quantification of reaction time at the molecular level and in-depth research on reaction mechanisms.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-18
- Publication Date
- 2026-03-10
AI Technical Summary
Existing technologies for detecting intermediates in catalytic reactions are difficult to implement in-situ real-time detection, and the residence time cannot be flexibly controlled, which limits the depth of research on catalytic reaction mechanisms and the development of high-performance catalysts.
A dual-pulse reaction device is designed, integrating a high-speed pulse valve and a vacuum microreactor. The residence time of the reaction gas in the vacuum microreactor is controlled by timing, and an in-situ detection is performed using a time-of-flight mass spectrometer with an adjustable energy electron bombardment ionization source and a single-photon ionization source.
It enables the quantitative detection of reaction times at the molecular level down to the millisecond level, simplifies experimental procedures, obtains clearer reaction mechanism data, reduces the difficulty of ionization fragmentation, and improves the efficiency of catalytic reaction research.
Smart Images
Figure CN121633238A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of in-situ detection technology of catalytic intermediates, specifically relating to a dual-pulse reaction device for studying catalytic reaction mechanisms. Background Technology
[0002] In the fields of catalytic reaction mechanism research and high-performance catalyst development, the accurate monitoring of catalytic reaction intermediates is of irreplaceable and crucial significance. Accurate capture and analysis of intermediates can provide core evidence for revealing reaction pathways and clarifying reaction kinetics, thereby guiding the design and optimization of highly efficient catalysts. However, catalytic reaction intermediates generally exhibit high reactivity, short lifespans, and low formation quantities, leading to significant technical challenges in their in-situ real-time detection.
[0003] Mass spectrometry, with its excellent response speed and high sensitivity, exhibits unique advantages in the detection of intermediates and products in catalytic reactions, providing a feasible technical path to solve the aforementioned detection challenges. Currently, transient analysis methods for catalytic reaction products based on mass spectrometry have been applied to some extent. These methods typically integrate a high-speed pulse valve with a reactor placed in a vacuum chamber, and equip the reactor outlet with an electron impact ionization quadrupole mass spectrometer. By monitoring the distribution characteristics of products over time, the kinetic information of the reaction process can be obtained, thereby inferring the catalytic reaction mechanism.
[0004] However, existing reactors combining high-speed pulse valves and vacuum chambers have significant drawbacks: the residence time of reactants within the catalytic system is fixed due to factors such as the background vacuum bed filling method and reaction temperature, making it impossible to flexibly adjust the residence time according to research needs. This limitation hinders researchers from systematically studying the impact of residence time on the catalytic reaction process, intermediate formation, and product distribution, thus restricting the depth of catalytic reaction mechanism research and the efficiency of high-performance catalyst development.
[0005] Therefore, it is essential to develop a new dual-pulse reaction device for studying catalytic reaction mechanisms. Summary of the Invention
[0006] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a dual-pulse reaction device for studying catalytic reaction mechanisms. By using high-speed pulse valves at the inlet and outlet for timing control, it can study catalytic reaction mechanisms at the molecular level with millisecond-level residence time scales, solving the problems of difficulty in in-situ detection of catalytic reaction intermediates and difficulty in quantifying the residence time of molecular-level catalytic reactions.
[0007] To achieve the above objectives, the technical solution of the present invention is as follows: a dual-pulse reaction device for studying catalytic reaction mechanisms, comprising a gas path pulse and adjustment module, a catalytic reaction module, and a detection interface module; the gas path pulse and adjustment module includes a reactor inlet pulse valve, an inlet valve seat, a reactor inlet fine-tuning valve, and a reactor outlet fine-tuning valve; the catalytic reaction module includes a vacuum reaction tube; the detection interface module includes an outlet valve seat, a mass spectrometer inlet pulse valve, and a mass spectrometer interface; the inlet valve seat is closely attached to the bottom of the reactor inlet pulse valve; the reactor inlet fine-tuning valve is located horizontally to the inlet valve seat; the upper and lower ends of the vacuum reaction tube are respectively connected to the inlet valve seat and the outlet valve seat, and the outer side can be adapted to a light / heating device; the outlet valve seat is connected to the lower gas outlet of the vacuum reaction tube; the reactor outlet fine-tuning valve is located horizontally to the outlet valve seat; the mass spectrometer inlet pulse valve is located below the outlet valve seat and connects between the outlet fine-tuning valve and the mass spectrometer interface; the mass spectrometer interface device is located at the bottom of the reaction device and extends downward to connect to the mass spectrometer ionization chamber.
[0008] All necessary sealing points between components are sealed with O-rings to ensure that the instrument reaches the required vacuum level for operation.
[0009] In a preferred embodiment of the present invention, a time-of-flight mass spectrometry ionization source is provided at the reactor outlet at a distance of 0.5-1.5 mm. The time-of-flight mass spectrometry ionization source is configured with an integrated energy-adjustable electron bombardment ionization source and a single-photon ionization source. Using a time-of-flight mass spectrometer as an analytical tool provides fast response speed and full-spectrum tracing.
[0010] More preferably, the electron bombardment ionization is a type of hard ionization, and the single-photon ionization is a type of soft ionization. The two work together to achieve both hard and soft ionization, which can effectively reduce the ionization fragments of reactants and reduce the difficulty of subsequent data analysis.
[0011] The control system triggers a high-speed pulse valve to introduce the reactant gas into the microreactor. The reaction time of the reactant gas in the reaction tube is quantified by the timing control of the reactor inlet pulse valve and the mass spectrometer inlet pulse valve, or by the vacuum control of the reaction tube. The reactant gas reacts in the reactor containing a catalyst bed, and the effluent enters an ionization source for ionization. The ionized material is then transmitted to a time-of-flight mass spectrometer for detection and analysis. Information acquisition is completed by a high-speed signal acquisition card, ultimately enabling in-situ tracking and detection of species changes during the reaction process for the study of the reaction mechanism.
[0012] In a preferred embodiment of the present invention, the timing of the operation of the reactor inlet pulse valve and the mass spectrometer inlet pulse valve can be adjusted to control the reaction time of the reactants.
[0013] In a preferred embodiment of the present invention, the dual-pulse reaction device can be used for external in-situ spectroscopy and tandem chromatography.
[0014] In a preferred embodiment of the invention, the reactor outlet is positioned close to the ionization chamber to achieve effective capture of intermediate species.
[0015] In a preferred embodiment of the present invention, the temperature control of the dual-pulse reaction device is a contact or non-contact temperature control, which is suitable for the study of photothermal catalytic systems.
[0016] In a preferred embodiment of the present invention, low-pressure continuous reaction monitoring can be achieved by adjusting the inlet fine-tuning valve and the outlet fine-tuning valve.
[0017] The working principle is as follows:
[0018] (a) The vacuum reaction tube is pre-evacuated to a vacuum level better than 5 × 10⁻⁶ by the vacuum system through the outlet fine-tuning valve or by opening the mass spectrometer inlet pulse valve. -5 mbar, close the reactor inlet and outlet fine adjustment valves and pulse valves, the control system triggers the reactor inlet high-speed pulse valve to introduce the reaction gas into the vacuum reaction tube, after the reaction, trigger the mass spectrometer inlet pulse valve to introduce the reactants in the tube into the mass spectrometer end, and control the reaction time of the reactants by controlling the timing of the reactor inlet pulse valve and the mass spectrometer inlet pulse valve.
[0019] (ii) Inert gas enters the vacuum reaction tube through the reactor inlet fine-tuning valve, then through the outlet fine-tuning valve and a three-way valve; one path leads to the vacuum system, and the other path leads to other spectroscopic instruments such as chromatographs for quantitative analysis. The reactor inlet and outlet fine-tuning valves are controlled to maintain the vacuum reaction tube in a low-pressure flow state with a vacuum better than 10. -3 mbar, the reaction gas enters the reaction tube through the reactor inlet pulse valve, and the mass spectrometer inlet pulse valve is activated to take samples;
[0020] (III) The reaction gas enters the vacuum reaction tube through the reactor inlet fine-tuning valve, then through the outlet fine-tuning valve and a three-way valve. One path leads to the vacuum system, and the other path leads to other spectroscopic instruments such as chromatographs for quantitative analysis. The reactor inlet and outlet fine-tuning valves are controlled to maintain the vacuum reaction tube in a low-pressure flow state with a vacuum better than 10. -3 The sample is taken at the inlet pulse valve of the mass spectrometer (mbar). A time-of-flight mass spectrometry ionization source (equipped with an integrated adjustable-energy electron impact ionization source and a single-photon ionization source, with soft ionization to reduce ionization fragmentation) is set 1 mm from the reactor outlet at the mass spectrometer end. The reaction gas reacts in the reactor containing the catalyst bed, and the outlet material enters the ionization source for ionization; it is then transmitted to the time-of-flight mass spectrometer for detection and analysis. Information acquisition is completed by a high-speed signal acquisition card, ultimately realizing in-situ tracking and detection of species changes during the reaction process for the study of the reaction mechanism.
[0021] Compared with the prior art, the present invention has the following beneficial effects:
[0022] 1. This invention integrates a high-speed pulse valve with a vacuum microreactor, and achieves the quantification of reaction time through the timing control of the high-speed pulse valve's action or the vacuum control of the reactor.
[0023] 2. The present invention provides a time-of-flight mass spectrometer equipped with an adjustable energy electron bombardment ionization source and a single photon ionization source at the reactor outlet as an in-situ detection device to detect the distribution changes of reaction products over time, thereby inferring the reaction mechanism.
[0024] 3. This invention can obtain more concise and clear experimental data, and is simple to operate and time-saving. Attached Figure Description
[0025] Figure 1 The present invention includes a model and a cross-sectional view;
[0026] In the diagram: 1-Inlet pulse valve, inlet valve seat-2, reactor inlet fine-tuning valve-3, vacuum reaction tube-4, outlet valve seat-5, reactor outlet fine-tuning valve-6, mass spectrometer inlet pulse valve-7, mass spectrometer interface-8, mass spectrometer ionization chamber-9, 10-O-ring seal, 11-Grid selective membrane. Detailed Implementation
[0027] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited to these embodiments.
[0028] To address the challenges of in-situ detection of catalytic reaction intermediates and the difficulty in quantifying the residence time of catalytic reactions at the molecular level, this invention provides a dual-pulse reaction device for studying catalytic reaction mechanisms. It integrates a high-speed pulse valve with a vacuum microreactor, controlling the residence time of the reactant gas within the microreactor by the timing of the inlet and outlet high-speed pulse valves. A time-of-flight mass spectrometer equipped with an adjustable-energy electron impact ionization source and a single-photon ionization source is installed at the reactor outlet as an in-situ detection device to monitor the distribution changes of reaction products over time, thereby inferring the reaction mechanism. Compared to existing detection methods, this invention provides kinetic information on millisecond-level reaction time changes at the molecular level.
[0029] A dual-pulse reaction device for studying catalytic reaction mechanisms includes a gas path pulse and regulation module, a catalytic reaction module, and a detection interface module. The gas path pulse and regulation module includes a reactor inlet pulse valve 1, an inlet valve seat 2, a reactor inlet fine-tuning valve 3, and a reactor outlet fine-tuning valve 6. The catalytic reaction module includes a vacuum reaction tube 4. The detection interface module includes an outlet valve seat 5, a mass spectrometry inlet pulse valve 7, and a mass spectrometry interface 8. The inlet valve seat 2 is located below the reactor inlet pulse valve 1 and above the vacuum reaction tube 4. The reactor inlet fine-tuning valve 3 is located horizontally to the side of the inlet valve seat 2. The vacuum reaction tube 4 runs vertically through the middle of the device, with its upper and lower ends connected to the inlet valve seat 2 and outlet valve seat 5, respectively. An illumination / heating device can be fitted to its outer side. The outlet valve seat 5 connects to the lower outlet of the vacuum reaction tube 4. A grid selective membrane 11 is installed at the lower end of the vacuum reaction tube 4, with the grid serving as a support below the membrane, and the outlet located below the grid. The reactor outlet fine-tuning valve 6 is located horizontally to the side of the outlet valve seat 5. The mass spectrometer inlet pulse valve 7 is located below the outlet valve seat 5 and connects to the outlet fine-tuning valve 6 and the mass spectrometer interface 8. The mass spectrometer interface 8 is located at the bottom of the reaction device, extending downwards to connect to the mass spectrometer ionization chamber 9. All required seals between components are achieved using O-rings 10 to ensure the instrument reaches the required vacuum level.
[0030] A time-of-flight mass spectrometry (TOFMS) ionization source is installed 0.5-1.5 mm from the reactor outlet. The TOFMS ionization source is equipped with an integrated energy-adjustable electron bombardment ionization source and a single-photon ionization source. Using a time-of-flight mass spectrometer as the analytical method provides fast response and full-spectrum tracing.
[0031] The electron bombardment ionization is a type of hard ionization, while single-photon ionization is a type of soft ionization. The two work together to achieve both hard and soft ionization, which can effectively reduce the ionization fragments of reactants and reduce the difficulty of subsequent data analysis.
[0032] The timing of the reactor inlet pulse valve and the mass spectrometer inlet pulse valve can be adjusted to control the reaction time of the reactants.
[0033] The dual-pulse reaction device can be used with external in-situ spectroscopy and tandem chromatography.
[0034] The reactor outlet is located close to the ionization chamber, which facilitates the effective capture of intermediate species.
[0035] The temperature control of the dual-pulse reaction device is either contact or non-contact, and is suitable for the study of photothermal catalytic systems.
[0036] Low-pressure continuous reaction monitoring can be achieved by adjusting the inlet and outlet fine-tuning valves.
[0037] This dual-pulse reaction device can obtain kinetic information on millisecond-level reaction time changes at the molecular level, track changes in reactant species in situ, and simultaneously perform both electron bombardment ionization and single-photon ionization, significantly reducing ionization fragmentation of reactant species, effectively reducing the difficulty of data analysis, and facilitating the study of reaction mechanisms.
[0038] The working process is as follows: The vacuum system pre-evacuates the vacuum reaction tube to a vacuum level better than 5 × 10⁻⁶ by using the outlet fine-tuning valve of the dual-pulse reaction device or by opening the inlet pulse valve of the mass spectrometer. -5 At mbar, the reactor inlet and outlet fine-tuning valves and pulse valves are closed. The control system triggers the reactor inlet high-speed pulse valve to introduce the reactant gas into the vacuum reaction tube. After the reaction, the mass spectrometer inlet pulse valve is triggered to introduce the reactants into the mass spectrometer end. The residence time of the reactants is controlled by controlling the timing of the reactor inlet pulse valve and the mass spectrometer inlet pulse valve. If it is an inert gas, the inert gas enters the vacuum reaction tube through the reactor inlet fine-tuning valve, then through the outlet fine-tuning valve and a three-way valve, one path leading to the vacuum system, and the other path leading to other spectroscopic instruments such as chromatographs for quantitative analysis. The reactor inlet and outlet fine-tuning valves are controlled to maintain the vacuum reaction tube in a low-pressure flow state with a vacuum better than 10. -3 In mbar, the reactant gas enters the reaction tube through the reactor inlet pulse valve, and the mass spectrometer inlet pulse valve is activated for sampling. Alternatively, the reactant gas enters the vacuum reaction tube through the reactor inlet fine-tuning valve, then through the outlet fine-tuning valve and a three-way valve, one path leading to the vacuum system, and the other path leading to other spectroscopic instruments such as chromatographs for quantitative analysis. The reactor inlet and outlet fine-tuning valves are controlled to maintain the vacuum reaction tube in a low-pressure flow state with a vacuum better than 10 mbar. -3 The mbar is used for sampling at the inlet pulse valve of the mass spectrometer. A time-of-flight mass spectrometry ionization source (equipped with an integrated adjustable-energy electron impact ionization source and a single-photon ionization source, with soft ionization to reduce ionization fragmentation) is set at the reactor outlet of the mass spectrometer. The reaction gas reacts in the reactor containing the catalyst bed, and the outlet material enters the ionization source for ionization; it is then transmitted to the time-of-flight mass spectrometer for detection and analysis. Information acquisition is completed by a high-speed signal acquisition card, ultimately realizing in-situ tracking and detection of species changes during the reaction process for the study of the reaction mechanism.
[0039] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A dual-pulse reaction apparatus for catalytic reaction mechanism study, characterized by, The double-pulse reaction device comprises a gas path pulse and regulation module, a catalytic reaction module, and a detection interface module; the gas path pulse and regulation module comprises a reactor inlet pulse valve, an inlet valve seat, a reactor inlet fine adjustment valve, and a reactor outlet fine adjustment valve; the catalytic reaction module comprises a vacuum reaction tube; the detection interface module comprises an outlet valve seat, a mass spectrometry inlet pulse valve, and a mass spectrometry interface; the inlet valve seat is close to the lower side of the reactor inlet pulse valve; the reactor inlet fine adjustment valve is located on the horizontal side of the inlet valve seat; the vacuum reaction tube is connected to the inlet valve seat and the outlet valve seat at the upper and lower ends, respectively, and can be adapted to an illumination / heating device on the outside; the outlet valve seat is connected to the lower end of the vacuum reaction tube; the reactor outlet fine adjustment valve is located on the horizontal side of the outlet valve seat; the mass spectrometry inlet pulse valve is located below the outlet valve seat and is connected between the outlet fine adjustment valve and the mass spectrometry interface; the mass spectrometry interface device is at the bottom end of the reaction device and extends downward to connect the mass spectrometry ionization chamber.
2. The dual-pulse reaction apparatus for catalytic reaction mechanism study according to claim 1, wherein, The time-of-flight mass spectrometry ionization source is arranged at 0.5-1.5 mm of the reactor outlet.
3. The dual-pulse reaction apparatus for catalytic reaction mechanism study according to claim 2, wherein, The time-of-flight mass spectrometry ionization source is configured with an integrated energy-adjustable electron impact ionization source and a single-photon ionization source.
4. The dual-pulse reaction apparatus for catalytic reaction mechanism study according to claim 3, wherein, The electron impact ionization belongs to hard ionization, and the single-photon ionization belongs to soft ionization.
5. The dual-pulse reaction apparatus for catalytic reaction mechanism study according to claim 1, wherein, The action timing of the reactor inlet pulse valve and the mass spectrometry inlet pulse valve can be adjusted to control the reaction time of the reactants.
6. The dual-pulse reaction apparatus for catalytic reaction mechanism study according to claim 1, wherein, The double-pulse reaction device can be externally connected to an in-situ spectrum and a tandem chromatogram.
7. The dual-pulse reaction apparatus for catalytic reaction mechanism study according to claim 1, wherein, The reactor outlet is arranged close to the ionization chamber.
8. The dual-pulse reaction apparatus for catalytic reaction mechanism study according to claim 1, wherein, The temperature control of the double-pulse reaction device is contact or non-contact temperature control.
9. The dual-pulse reaction apparatus for catalytic reaction mechanism study according to claim 1, wherein, Low-pressure continuous reaction monitoring can be realized by adjusting the inlet fine adjustment valve and the outlet fine adjustment valve.