Electromagnetically isolated thermally coupled dielectric barrier discharge reactor and system

Abstract

The application discloses an electromagnetic isolation thermal coupling dielectric barrier discharge reaction device and system, and relates to the technical field of plasma detection and analysis. The device comprises a reaction tube assembly, a plasma generation assembly and a thermal regulation assembly. The reaction tube assembly defines an upstream discharge zone and a downstream heating zone along the gas flow direction. The plasma generation assembly is arranged in the upstream discharge zone, and the thermal regulation assembly is arranged in the downstream heating zone and comprises an insulating heating shell and a first heating element. The downstream heating section of the reaction tube assembly is arranged in the heating shell and is spaced apart from the heating shell. An electrically isolated sealing part at the front end of the heating shell is sealingly connected with the reaction tube assembly to cut off the high-voltage electric field creeping path and inhibit electromagnetic coupling interference. The device can be combined with a multi-stage vacuum exhaust system and a mass spectrometer to realize the online monitoring of the intermediate product after the plasma activation and the controlled thermal reaction.

Description

Technical Field

[0001] This invention relates to the field of plasma detection and analysis technology, and in particular to an electromagnetically isolated thermally coupled dielectric barrier discharge reaction device and system. Background Technology

[0002] Dielectric barrier discharge (DPD) technology in plasma generation is widely used in materials modification, pollutant treatment, and assisted chemical synthesis. Existing DPD devices typically operate at near-room temperature, primarily utilizing electron energy to initiate chain reactions. However, when facing complex multi-step gas-phase synthesis reactions such as alkane reforming or directed synthesis, while plasma can efficiently complete bond-breaking processes and generate free radicals, subsequent free radical recombination, isomerization, or product desorption are often thermodynamically controlled. Existing single-excitation mode devices lack an independent thermal field control dimension, leading to low synthesis efficiency for some target products or the generation of numerous byproducts due to intermediates' inability to overcome the potential barrier.

[0003] To introduce a thermal activation mechanism, a controlled high-temperature environment needs to be constructed within a compact reaction space. However, dielectric barrier discharge typically relies on a high-frequency, high-voltage power supply, while conventional electric heating and temperature measurement systems are low-voltage sensitive circuits. Within the compact reactor space, the high-voltage electric field is highly susceptible to coupling or breakdown with the heating components, generating severe electromagnetic interference. This not only affects the accuracy of temperature control but may also damage precision analytical instruments such as mass spectrometers connected downstream.

[0004] Therefore, how to block the creepage path of the high-voltage electric field and suppress electromagnetic coupling interference through physical structure design in a compact reaction space, so as to achieve synergistic compatibility between plasma activation and thermal field control, has become an urgent technical problem to be solved. Summary of the Invention

[0005] The main objective of this invention is to provide an electromagnetically isolated thermally coupled dielectric barrier discharge reaction device and system, which aims to block the creepage path of the high-voltage electric field and suppress electromagnetic coupling interference within a compact reaction space through physical structural design, so as to achieve synergistic compatibility between plasma activation and thermal field control.

[0006] To achieve the above objectives, the present invention proposes an electromagnetically isolated thermally coupled dielectric barrier discharge reaction device, comprising: The reaction tube assembly has an internal flow channel that defines an upstream discharge zone and a downstream heating zone along the gas flow direction. A plasma generating assembly is disposed in the upstream discharge region; A thermal control component is disposed in the downstream heating zone, and the thermal control component includes a heating housing and a first heating element; The heating shell is a hollow structure made of insulating material. The downstream heating section of the reaction tube assembly is at least partially inserted into the cavity of the heating shell and is arranged at a distance from the heating shell. The first heating element is disposed on the heating housing. Under the heating action of the first heating element, the heating housing acts as an independent heating carrier, and performs non-contact heating on the reaction tube assembly inserted therein through thermal radiation or thermal convection. The heating housing has an electrically isolated sealing part at one end near the upstream discharge region. The electrically isolated sealing part is sealed to the reaction tube assembly to form an insulating physical isolation interface between the upstream discharge region and the downstream heating region, so as to cut off the creepage path of the high voltage electric field to the thermal control component and suppress electromagnetic coupling interference.

[0007] Preferably, the heating housing is made of alumina ceramic or quartz material; the electrically isolated sealing part is constructed as an annular sealing surface protruding from the front end of the heating housing.

[0008] Preferably, the thermal control component is covered with an external insulation component; the external insulation component includes a first insulation layer and a second insulation layer, the first insulation layer is a mullite insulation layer covered with the heating shell, and the second insulation layer is a foam ceramic insulation layer covered with the first insulation layer.

[0009] Preferably, it also includes a temperature monitoring component, which includes a first temperature monitoring element, which is a thermocouple disposed on the wall of the heating shell.

[0010] Preferably, the reaction tube assembly is an integrally formed quartz glass tube of varying diameters.

[0011] Preferably, the assembly further includes an ultrasonic molecular beam injection component connected to the end of the reaction tube assembly; the ultrasonic molecular beam injection component includes a bonding shell, a quartz nozzle, and a molecular beam extractor; the bonding shell is a hollow structure with a vacuum cavity, and the bonding shell is provided with a first through hole and a second through hole communicating with the vacuum cavity; the quartz nozzle is connected to the first through hole and partially extends into the end of the reaction tube assembly; the molecular beam extractor is installed in the vacuum cavity and located downstream of the quartz nozzle.

[0012] Preferably, the ultrasonic molecular beam injection assembly further includes a deflection electrode assembly; the deflection electrode assembly is disposed downstream of the molecular beam extractor and is used to deflect and separate charged particles passing through the molecular beam extractor.

[0013] Preferably, it further includes an auxiliary heating assembly, which includes a second heating element disposed at the connection between the quartz nozzle and the end of the reaction tube assembly.

[0014] Preferably, the system further includes a multi-stage vacuum exhaust system, which includes a first vacuum chamber, a second vacuum chamber, and a third vacuum chamber connected sequentially along the reaction product transport direction; the end of the reaction tube assembly is connected to the first vacuum chamber.

[0015] Preferably, the first vacuum chamber is connected to a first pump group evacuation pipe, and a pump group butterfly valve is installed on the first pump group evacuation pipe; a vacuum gauge is installed on the first vacuum chamber, and the signal output terminal of the vacuum gauge is connected to a pressure controller, and the signal output terminal of the pressure controller is connected to the pump group butterfly valve, for adjusting the opening of the pump group butterfly valve to maintain a constant pressure in the first vacuum chamber.

[0016] This application also discloses a mass spectrometry analysis system, including a mass spectrometer and an electromagnetically isolated thermally coupled dielectric barrier discharge reaction device as described above. The mass spectrometer is connected to the third vacuum chamber. The mass spectrometer is equipped with an optical path interface for receiving synchrotron radiation vacuum ultraviolet light, and uses the received synchrotron radiation vacuum ultraviolet light as an ionization source to soft ionize neutral molecules entering the third vacuum chamber. Through the cascaded differential pumping of the multi-stage vacuum exhaust system, the third vacuum chamber is kept in a high vacuum environment to meet the requirements for synchrotron radiation source access, wherein the pressure inside the third vacuum chamber is no greater than […]. .

[0017] The above technical solution has the following advantages: By providing an electrically isolated sealing section at one end of the heating shell near the upstream discharge region and sealing it with the reaction tube assembly, a physical isolation interface is formed between the discharge region and the heating region in space. This electromagnetic isolation structure allows the heating shell, as an independent heating carrier, to effectively cut off the creepage path from the upstream high-voltage electric field to the thermal control component using its annular sealing surface, thereby suppressing electromagnetic coupling interference. This design solves the technical defect of the difficulty in incorporating high-voltage discharge and precise temperature control in a compact space, ensuring that the device maintains high-intensity nanosecond pulse discharge to efficiently pyrolyze the reaction gas while guaranteeing the safe and stable operation of the downstream heating circuit and subsequent temperature control system. By realizing a synergistic mechanism of plasma activation followed by controlled thermal reaction, this invention significantly improves the efficiency of gas-phase synthesis reactions and the selectivity of target products. Attached Figure Description

[0018] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings, wherein: Figure 1This is a schematic diagram of the electromagnetically isolated thermally coupled dielectric barrier discharge reaction device provided in an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the electromagnetically isolated thermally coupled dielectric barrier discharge reaction device and the electrically isolated sealing part at the front end of the heating shell provided in an embodiment of the present invention.

[0020] Figure 3 This is an assembly diagram of an electromagnetically isolated thermally coupled dielectric barrier discharge reaction device used in conjunction with a mass spectrometer, as provided in an embodiment of the present invention.

[0021] Figure 4 The mass spectrum obtained by the mass spectrometry analysis system provided in this embodiment of the invention during in-situ analysis of the reaction between methane and ammonia is shown in the figure. Figure 4 (a) in the image represents the mass spectrum of the sample gas when plasma discharge and downstream heating are not enabled. Figure 4 (b) in the image represents the mass spectrum of the reaction products when plasma discharge is enabled but downstream heating is disabled. Figure 4 (c) in the figure represents the mass spectrum of the reaction products when plasma discharge and downstream heating are turned on simultaneously.

[0022] Figure 5 The graph showing the relationship between the set temperature of the heating shell and the actual temperature inside the reactor is provided for an embodiment of the present invention. The horizontal axis represents the measurement position along the axial direction of the reaction tube assembly, and the vertical axis represents the actual temperature at the corresponding position. Different curves represent the temperature distribution under different set temperatures of the heating shell. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. The described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] Example 1 like Figures 1 to 5 As shown, this embodiment provides an electromagnetically isolated thermally coupled dielectric barrier discharge reaction device and mass spectrometry analysis system based on synchrotron radiation photoionization. In the field of gas-phase chemical synthesis, especially in complex reactions involving alkane reforming or directed synthesis, although traditional low-temperature dielectric barrier discharge devices can efficiently break chemical bonds and generate free radicals through high-energy electrons, the subsequent free radical recombination or isomerization processes are often thermodynamically controlled. Existing devices lack an independent thermal field control dimension, resulting in low selectivity for the target product.

[0025] However, directly introducing heating components into the compact reactor space presents significant engineering challenges. The high-frequency, high-voltage electric field required for dielectric barrier discharge is highly susceptible to coupling with or breaking down the low-voltage heating circuit, generating electromagnetic interference and damaging the precision temperature control system. To address this technical challenge of incompatibility between high-voltage discharge and precision temperature control, this embodiment constructs a synergistic reaction system with an electromagnetic isolation structure.

[0026] The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device specifically includes a reaction tube assembly 1. The reaction tube assembly 1 has an internal flow channel and defines an upstream discharge zone and a downstream heating zone along the gas flow direction. The reaction tube assembly 1 includes an integrally formed quartz glass tube body of varying diameter and an inlet connection assembly connected to the inlet end of the quartz glass tube body; the inlet connection assembly includes a hand-tightening connector 101, a four-way connector 102, a quartz cap 103, and a hand-tightening adapter 104 for connecting to an external gas supply pipeline.

[0027] A plasma generating assembly is provided in the upstream discharge region. The plasma generating assembly includes a copper electrode 2 and a ceramic casing 3 fitted over the outside of the reaction tube assembly 1. The copper electrode 2 is disposed on the outer wall of the upstream section of the reaction tube assembly 1 and is used to conduct the high-voltage pulse signal provided by the nanosecond pulse power supply 9. In some embodiments, the plasma generating assembly specifically includes a ceramic casing 105 and the copper electrode 2 disposed therein, and is secured by ceramic screws 107. The copper electrode 2 is connected to the nanosecond pulse power supply 9, which not only provides high-voltage pulses but also ensures the stability of the discharge.

[0028] A thermal control assembly is provided in the downstream heating zone. The thermal control assembly includes a heating shell 4 and a first heating element 5. The heating shell 4 is a hollow tubular structure made of insulating materials such as alumina ceramic or quartz. The downstream heating section of the reaction tube assembly 1 is at least partially inserted into the cavity of the heating shell 4, and a certain radial gap is maintained between the outer wall of the reaction tube assembly 1 and the inner wall of the heating shell 4, forming an intermittent arrangement. The first heating element 5 is specifically a first heating wire wound around the outer circumference of the heating shell 4. By energizing the first heating element 5, the heating shell 4 is heated and generates uniform thermal radiation, thereby providing non-contact heating to the reaction tube assembly 1 inserted therein.

[0029] The core of this embodiment lies in the fact that the heating housing 4 has an electrically isolated sealing part at one end near the upstream discharge region. The electrically isolated sealing part is constructed as an annular sealing surface 108 protruding from the front end of the heating housing 4, which is sealed to the outer wall of the quartz tube of the reaction tube assembly 1. The annular sealing surface 108 spatially forms a physical isolation interface between the upstream discharge region and the downstream heating region. Through this design, the heating housing 4, as an independent heating carrier, effectively cuts off the creepage path from the upstream high-voltage electric field to the thermal control component by utilizing the annular sealing surface 108 at the front end, thereby suppressing electromagnetic coupling interference. This electromagnetic isolation structure enables the device to maintain the upstream high-intensity nanosecond pulse discharge, for example, 5 kV to 10 kV, while ensuring the safe and stable operation of the downstream heating circuit and subsequent temperature control system; at the same time, the heating housing, as an independent heating carrier, is arranged at intervals with the reaction tube, realizing modular decoupling of the heating component and the reaction tube, which facilitates quick replacement of heating elements and subsequent maintenance, and avoids the problem of the entire reaction device being scrapped due to damage to the heating wire or thermocouple.

[0030] To improve thermal efficiency and protect operators, an external insulation component is installed around the thermal control assembly. This external insulation component includes a first insulation layer 8 and a second insulation layer 6. The first insulation layer 8 is specifically a mullite insulation layer installed around the heating housing 4 to reduce heat loss. The second insulation layer 6 is specifically a foam ceramic insulation layer installed around the first insulation layer 8 to reduce the surface temperature of the device.

[0031] The device also includes a temperature monitoring component for precise temperature control. The temperature monitoring component includes a first temperature monitoring element 7. Specifically, the first temperature monitoring element 7 is a thermocouple, which is disposed on the wall of the heating housing 4 or in the gap between the heating housing 4 and the reaction tube. The signal output terminal of the first temperature monitoring element 7 is connected to a temperature controller 17, and the signal output terminal of the temperature controller 17 is connected to the signal input terminal of the first heating element 5. Through closed-loop control, the temperature controller 17 can adjust the heating power of the first heating element 5 in real time based on the temperature data fed back by the first temperature monitoring element 7, so that the temperature of the downstream heating zone can be accurately maintained within the experimentally set range, such as maintaining any target temperature between room temperature and 1000 °C.

[0032] The end of the reaction tube assembly is connected to a multi-stage vacuum exhaust system via an ultrasonic molecular beam injection assembly to introduce the reaction products into the subsequent mass spectrometry analysis unit. The ultrasonic molecular beam injection assembly is connected to the end of the reaction tube assembly 1. Specifically, this assembly includes a junction housing, a quartz nozzle 11, and a molecular beam extractor 12. The junction housing is a hollow structure with a vacuum cavity, and has a first through hole and a second through hole communicating with the vacuum cavity. The quartz nozzle 11 is connected to the first through hole and extends partially into the end of the reaction tube assembly 1. The second through hole is located downstream of the quartz nozzle 11 and is used to transmit the molecular beam extracted by the molecular beam extractor 12 to the subsequent vacuum region. The molecular beam extractor 12 is specifically made of nickel material, installed in the vacuum cavity and located downstream of the quartz nozzle 11. The tip aperture of the molecular beam extractor 12 is coaxially aligned with the outlet of the quartz nozzle 11, and the tip of the molecular beam extractor 12 extends at least partially into the expansion region at the outlet of the quartz nozzle 11 to form a two-stage differential structure. The reaction products are ejected from the high-pressure reaction tube through a quartz nozzle 11 into a low-pressure environment, undergoing an adiabatic expansion process to form a supersonic molecular beam. A nickel molecular beam extractor 12 then extracts the high-concentration portion at the center of the molecular beam. To prevent non-volatile products from condensing and clogging the nozzle, the device also includes an auxiliary heating assembly. This auxiliary heating assembly includes a second heating element 10, which is located at the connection between the quartz nozzle 11 and the end of the reaction tube assembly 1.

[0033] To filter charged particles, the ultrasonic molecular beam injection assembly also includes a deflection electrode assembly 13. The deflection electrode assembly 13 is located downstream of the molecular beam interceptor 12, specifically at the end of the second vacuum chamber 20. By applying a DC deflection voltage to the deflection electrode assembly 13 via a DC power supply 18, the deflection electric field can remove charged particles such as ions or electrons trapped in the molecular beam, thereby allowing only neutral molecules to enter the subsequent detection region and significantly reducing the background noise of mass spectrometry detection.

[0034] The device is equipped with a multi-stage vacuum exhaust system, including a first vacuum chamber 19, a second vacuum chamber 20, and a third vacuum chamber 21 connected sequentially along the reaction product transport direction. The first vacuum chamber 19 serves as the first vacuum chamber, with the end of the reaction tube assembly 1 connected to its interior. The second vacuum chamber 20 serves as the second vacuum chamber, housing a deflection electrode assembly 13. The third vacuum chamber 21 serves as the third vacuum chamber. Each vacuum chamber is connected to an independent extraction pipe, namely, a first pump group extraction pipe 24, a second pump group extraction pipe 25, and a third pump group extraction pipe 26, thus forming a progressively decreasing pressure gradient. A vacuum gauge 16 is installed on the first vacuum chamber 19, and its signal output is connected to a pressure controller 22. The pressure controller 22 controls the opening of the pump group butterfly valve 23 on the first pump group extraction pipe 24, stabilizing the pressure within the first vacuum chamber 19 at a set value, such as 30 Torr. The pressure within the third vacuum chamber 21 is maintained at no more than... The high vacuum level is required to meet the access requirements of synchrotron radiation sources.

[0035] The mass spectrometry system utilizes synchrotron radiation vacuum ultraviolet light 27 as an ionization source. The synchrotron radiation vacuum ultraviolet light 27 is introduced through an optical path interface on the side wall of the third vacuum chamber 21, with its optical path axis orthogonal to the molecular beam direction. Neutral molecules entering the third vacuum chamber 21 are soft-ionized by the synchrotron radiation, and the resulting ions, accelerated by the accelerating electrode plate 14, enter the mass spectrometer through the ion introducer 15 for detection. This mechanism, which involves plasma activation followed by a controlled thermal reaction, and then combined with synchrotron radiation soft ionization detection, can capture extremely low concentrations of intermediates and free radicals during the reaction process.

[0036] Example 2 In another alternative embodiment, the present invention further optimizes the multi-stage vacuum exhaust system and the product sampling process to ensure accurate capture of transient intermediates generated during plasma reactions. This system achieves a smooth transition from a near-ambient pressure reaction environment to a high-vacuum detection environment by constructing multi-stage pressure gradients. Specifically, the multi-stage vacuum chambers include a first vacuum chamber 19, a second vacuum chamber 20, and a third vacuum chamber 21 connected sequentially. The first vacuum chamber 19 serves as the direct containment space for product generation, and its internal pressure is maintained at approximately 30 Torr by adjusting the pump assembly butterfly valve 23. This pressure selection effectively reduces secondary collisions between molecules, thereby maximizing the preservation of highly reactive reactive free radicals.

[0037] Product sampling is achieved through an ultrasonic molecular beam injection assembly. The end of the reaction tube assembly 1 is connected to a quartz nozzle 11, the outlet of which extends into the second vacuum chamber 20. A nickel molecular beam extractor 12 is coaxially positioned between the second and third vacuum chambers 20 and 21. When the reactant gas is injected into the second vacuum chamber 20 through the quartz nozzle 11, it undergoes adiabatic expansion due to the significant pressure difference, forming a supersonic molecular beam. The nickel molecular beam extractor 12 is responsible for extracting the portion of the molecular beam with higher kinetic energy and concentration at its center into the third vacuum chamber 21. To maintain a high vacuum in the third vacuum chamber 21, i.e., a pressure not exceeding [a certain value], [further measures are taken]. Each level of compartment is equipped with an independently controlled air extraction pipeline, namely the first pump group air extraction pipeline 24, the second pump group air extraction pipeline 25, and the third pump group air extraction pipeline 26.

[0038] At the end of the second vacuum chamber 20, behind the nickel molecular beam interceptor 12, a deflection electrode assembly 13 is disposed. This deflection electrode assembly 13 is electrically connected to an external DC power supply 18. Since a large number of charged particles, such as electrons or ions, are inevitably generated during plasma discharge, these particles, if they enter the third vacuum chamber 21, will produce extremely strong background interference, even masking the signal of neutral products. By applying a deflection voltage, for example, 600 V, to the deflection electrode assembly 13 through the DC power supply 18, a horizontal deflection electric field perpendicular to the direction of the molecular beam flow can be constructed. This electric field can guide charged particles away from the axis, thereby allowing only pure neutral product molecules to enter the third vacuum chamber 21 for subsequent soft ionization detection. This filtering mechanism significantly improves the signal-to-noise ratio of mass spectrometry analysis, and is particularly suitable for detecting trace intermediates in the PPM range.

[0039] The neutral molecular beam entering the third vacuum chamber 21 undergoes orthogonal collisions with the synchrotron radiation vacuum ultraviolet light 27. Under the influence of the synchrotron radiation, the molecules undergo soft ionization to generate ions. The third vacuum chamber 21 also houses an accelerating electrode plate 14 and an ion introducer 15. The accelerating electrode plate 14 is positioned at the sample inlet of the ion introducer 15, applying an accelerating electric field to extract and accelerate the ionized ions. Finally, the ions pass through the ion introducer 15 into the time-of-flight mass spectrometry analysis unit for mass analysis. To prevent high-boiling-point products from condensing at the sampling inlet, this embodiment also includes a second heating element 10 wrapped around the base of the quartz nozzle 11, ensuring the product remains in the gas phase through active heating.

[0040] Example 3 This embodiment further verifies the technical advantages of the synergistic mechanism of plasma activation followed by controlled thermal reaction proposed in this invention through a specific experiment on the reaction of methane (CH4) and ammonia (NH3) to produce hydrogen cyanide (HCN). In the experiment, methane, ammonia, and argon as a carrier gas were introduced into the reaction tube assembly 1 through a mass flow controller at flow rates of 20 sccm, 20 sccm, and 400 sccm.

[0041] In the upstream discharge region, the voltage is adjusted to 6 kV and the pulse frequency is set to 700 Hz by the nanosecond pulse power supply 9. Under the action of the copper electrode 2, the high-voltage pulse excites a dielectric barrier discharge inside the reaction tube assembly 1, activating stable methane and ammonia molecules into active free radicals or ionic states. At this time, due to the physical isolation between the heating shell 4 and the upstream ceramic sleeve 3, and the electrically isolated sealing part at the front end of the heating shell 4, the strong electromagnetic field generated by the high-voltage discharge is effectively shielded and will not interfere with the downstream temperature controller 17 and the first temperature monitoring element 7.

[0042] In the downstream heating zone, the power of the first heating element 5 is adjusted by the temperature controller 17 to reheat the plasma-activated gas flow. Through adjustment, the actual internal temperature of the reactor reaches approximately 440 °C, while the set temperature of the heating shell 4 is approximately 500 °C. The obtained mass spectrum shows that under an ionization energy of 14.5 eV, such as... Figure 4 As shown in (a), when plasma discharge and downstream heating are not activated, the mass spectrum mainly reflects signals from the sample gases such as methane and ammonia; Figure 4 As shown in (b), when only plasma discharge is activated without downstream heating, the hydrogen cyanide signal peak at m / z = 27 is relatively low, and its ratio to the background peak at m / z = 32 (oxygen) is approximately 1:3; while... Figure 4 As shown in (c), when downstream heating is turned on and the temperature is raised to 500 °C, the signal intensity of hydrogen cyanide is significantly enhanced, and its ratio with the oxygen peak is close to 1:1.

[0043] Figure 5 Furthermore, the axial distribution of the actual internal temperature of the reactor under different heating shell set temperatures is presented. Figure 5 It can be seen that as the set temperature of the heating shell increases, the actual temperature at the corresponding position inside the reactor increases as a whole, and it exhibits a distribution characteristic of higher temperature in the middle and lower temperature at both ends along the axial direction. This temperature distribution can provide an adjustable thermal field environment for the downstream controlled thermal reaction.

[0044] This comparative result strongly demonstrates the crucial role of thermal effects in promoting CN bond recombination. In the architecture of this invention, upstream high-energy electrons are responsible for bond breaking and generating intermediates, while the downstream controlled thermal field provides the thermal activation energy required to overcome the reaction energy barrier, thereby significantly improving the synthesis efficiency of the target product. Due to the use of an electromagnetically isolated structure, this high-temperature synergistic reaction can operate stably for extended periods under high-voltage discharge conditions, with minimal temperature fluctuations inside the reactor, meeting the requirements for precise kinetic studies.

[0045] Example 4 In another alternative embodiment, the structure of the reaction tube assembly 1 can be adjusted according to different experimental requirements. Although different diameter quartz glass tubes were used in the above embodiments, ceramic tubes can also be used for the reaction tube assembly 1 when dealing with highly corrosive gases. In this case, the seal between the electrically isolated sealing part and the reaction tube assembly 1 can be achieved using sealant or mechanical ferrule connection. In addition, the heating element inside the heating housing 4 can be a wound heating wire or an embedded first heating element 5, such as a resistance wire pre-embedded inside the ceramic housing. This can provide a more uniform heat field distribution and further reduce the risk of electromagnetic radiation caused by the exposure of the heating wire. For temperature monitoring, in addition to using the first temperature monitoring element 7, an infrared temperature measuring element can also be installed at the observation hole of the heating housing 4 in some specific high-temperature extreme environments to achieve non-contact real-time temperature monitoring.

[0046] In summary, the electromagnetically isolated thermally coupled dielectric barrier discharge reaction device and mass spectrometry analysis system provided by this invention successfully solves the problem of incompatibility between plasma activation and thermodynamic control processes within a compact space through the physical isolation and synergistic effect of the upstream discharge region and the downstream heating region. This device not only utilizes a high-intensity electric field to generate highly reactive intermediates but also precisely controls the reaction path through a controlled thermal field, thereby significantly improving the efficiency of gas-phase synthesis reactions and the selectivity of target products. Combined with a multi-stage differential pumping system, deflection electrode noise reduction technology, and the soft ionization characteristics of synchrotron vacuum ultraviolet light, this invention achieves highly sensitive online monitoring of trace, short-lived intermediates in complex reaction systems, providing a powerful experimental tool for studying the kinetics of plasma chemical reactions.

[0047] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An electromagnetically isolated thermally coupled dielectric barrier discharge reaction device, characterized in that, include: The reaction tube assembly has an internal flow channel that defines an upstream discharge zone and a downstream heating zone along the gas flow direction. A plasma generating assembly is disposed in the upstream discharge region; A thermal control component is disposed in the downstream heating zone, and the thermal control component includes a heating housing and a first heating element; The heating shell is a hollow structure made of insulating material. The downstream heating section of the reaction tube assembly is at least partially inserted into the cavity of the heating shell and is arranged at a distance from the heating shell. The first heating element is disposed on the heating housing. Under the heating action of the first heating element, the heating housing acts as an independent heating carrier, and performs non-contact heating on the reaction tube assembly inserted therein through thermal radiation or thermal convection. The heating housing has an electrically isolated sealing part at one end near the upstream discharge region. The electrically isolated sealing part is sealed to the reaction tube assembly to form an insulating physical isolation interface between the upstream discharge region and the downstream heating region, so as to cut off the creepage path of the high voltage electric field to the thermal control component and suppress electromagnetic coupling interference.

2. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to claim 1, characterized in that, The heating housing is made of alumina ceramic or quartz material; the electrically isolated sealing part is constructed as an annular sealing surface protruding from the front end of the heating housing.

3. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to claim 1, characterized in that, The thermal control component is covered with an external insulation component; the external insulation component includes a first insulation layer and a second insulation layer, the first insulation layer is a mullite insulation layer covered with the heating shell, and the second insulation layer is a foam ceramic insulation layer covered with the first insulation layer.

4. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to claim 1, characterized in that, It also includes a temperature monitoring component, which includes a first temperature monitoring element, which is a thermocouple disposed on the wall of the heating shell.

5. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to claim 1, characterized in that, The reaction tube assembly is a one-piece molded quartz glass tube of varying diameters.

6. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to claim 1, characterized in that, It also includes an ultrasonic molecular beam injection assembly, which is connected to the end of the reaction tube assembly; the ultrasonic molecular beam injection assembly includes a bonding shell, a quartz nozzle, and a molecular beam extractor; the bonding shell is a hollow structure with a vacuum cavity, and the bonding shell is provided with a first through hole and a second through hole communicating with the vacuum cavity; the quartz nozzle is connected to the first through hole and extends partially into the end of the reaction tube assembly; the molecular beam extractor is installed in the vacuum cavity and located downstream of the quartz nozzle.

7. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to claim 6, characterized in that, The ultrasonic molecular beam injection assembly further includes a deflection electrode assembly; the deflection electrode assembly is disposed downstream of the molecular beam extractor and is used to deflect and separate charged particles passing through the molecular beam extractor.

8. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to claim 6, characterized in that, It also includes an auxiliary heating assembly, which includes a second heating element disposed at the connection between the quartz nozzle and the end of the reaction tube assembly.

9. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to any one of claims 6 to 8, characterized in that, It also includes a multi-stage vacuum exhaust system, which includes a first vacuum chamber, a second vacuum chamber, and a third vacuum chamber connected sequentially along the reaction product transport direction. The end of the reaction tube assembly is connected to the first vacuum chamber.

10. The electromagnetically isolated thermally coupled dielectric barrier discharge reaction device according to claim 9, characterized in that, The first vacuum chamber is connected to a first pump group evacuation pipe, and a pump group butterfly valve is installed on the first pump group evacuation pipe; a vacuum gauge is installed on the first vacuum chamber, and the signal output terminal of the vacuum gauge is connected to a pressure controller, and the signal output terminal of the pressure controller is connected to the pump group butterfly valve, which is used to maintain a constant pressure in the first vacuum chamber by adjusting the opening of the pump group butterfly valve.

11. A mass spectrometry analysis system, characterized in that, It includes a mass spectrometer and an electromagnetically isolated thermally coupled dielectric barrier discharge reaction device as described in claim 9 or 10, wherein the mass spectrometer is connected to the third vacuum chamber; the mass spectrometer is provided with an optical path interface for receiving synchrotron radiation vacuum ultraviolet light, and uses the received synchrotron radiation vacuum ultraviolet light as an ionization source to soft ionize neutral molecules entering the third vacuum chamber. The cascaded differential pumping of the multi-stage vacuum exhaust system ensures that the third vacuum chamber is in a high-vacuum environment to meet the requirements for synchrotron radiation source access. The pressure within the third vacuum chamber is no greater than […]. .

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