Device for identifying and analyzing species in low-temperature oxidation process of liquid fuel

Abstract

The invention provides a species identification and analysis device in a liquid fuel low-temperature oxidation process, which integrates a feeding system, a reaction system, a gas chromatography-time-of-flight mass spectrometer (GC-TOFMS) and a computer data acquisition and processing system, and ensures stable temperature and flow of reaction gas by accurately controlling the feeding system, so that the species identification and analysis device can be used for identifying species in a liquid fuel low-temperature oxidation process. The method comprises the following steps of: introducing a sample into a chromatographic column to simulate different low-temperature oxidation conditions, uniformly mixing gas reactants by using a jet stirring reactor, enhancing the efficiency and uniformity of an oxidation reaction, extracting the gas by using a peristaltic pump, introducing the sample into the chromatographic column by adopting a non-split sample introduction mode beneficial to trace analysis, and realizing GC-TOFMS high-sensitivity species identification and measurement. According to the device, the experimental assembly, the feeding assembly, the gas chromatography and the flight time mass analyzer are integrated together, the efficiency and smoothness of experimental operation are greatly improved, and compared with a traditional distributed experimental device, the integrated design reduces the connection complexity and space occupation between experimental equipment.

Description

Technical Field

[0001] The present invention relates to the field of low-temperature oxidation of liquid fuels, and specifically to a device for species identification and analysis during the low-temperature oxidation of liquid fuels. Background Art

[0002] The auto-ignition process of fuels includes three stages: low-temperature oxidation, self-heating, and combustion. Among them, the initial heat accumulated during the low-temperature oxidation stage is the key to fuel auto-ignition. Moreover, the ignition time, power output, fuel flexibility, fuel economy, and emissions under auto-ignition conditions are also affected by the low-temperature oxidation reaction. During the low-temperature oxidation process, small molecule free radicals will first attack the fuel, thereby generating fuel free radicals. The fuel free radicals then initiate chain propagation and chain branching reactions. Among them, peroxyalkyl free radicals (ROO·) and their subsequent related reactions play an important role in this process.

[0003] Therefore, in order to improve the economy and environmental protection of fuel combustion, promote the application research and development of new fuels, and rationally utilize the auto-ignition phenomenon to design and optimize engines, it is necessary for us to understand and analyze the low-temperature oxidation reaction kinetics more deeply. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention proposes a device for species identification and analysis during the low-temperature oxidation of liquid fuels. This device integrates multiple experimental modules together, making the experimental operation more convenient, reducing manual operation errors, lowering the technical requirements and working intensity of operators, and reducing errors caused by improper operation.

[0005] The technical solution of the present invention is realized as follows:

[0006] A device for species identification and analysis during the low-temperature oxidation of liquid fuels, which integrates a feeding system, a reaction system, a gas chromatography-time of flight mass spectrometer (GC-TOFMS), and a computer data acquisition and processing system. Inside the experimental host, multiple groups of experimental components are fixedly installed, and a feeding component is fixedly installed above. The reaction gas is introduced into the interior of the experimental host through the feeding component, the reaction is carried out through the experimental components, and GC-TOFMS is used for species identification and analysis. An experimental chamber is opened inside the experimental host. A reactor is fixedly installed in the upper left of the experimental chamber. Inside the reactor, a jet stirred reactor is fixedly installed, which is arranged directly below the feeding component. A K-type thermocouple is fixedly installed inside the jet stirred reactor. A sampling tube is connected to the outlet of the reactor, and the other end of the sampling tube is connected to the gas chromatography. A mass spectrometer is fixedly installed on the right side of the gas chromatography, and a data acquisition and processor is fixedly installed above the mass spectrometer.

[0007] A further improvement lies in that: the feeding assembly includes a liquid flow controller, a vaporization device and a connecting pipe. The liquid flow controller is fixedly installed on the left side of the top of the experimental mainframe. The vaporization device is fixedly installed at the bottom of the liquid flow controller. The right side of the vaporization device is fixedly connected to the connecting pipe, and the other end of the connecting pipe is connected to the oxygen tank.

[0008] A further improvement lies in that: a feeding port is arranged at the top of the liquid flow controller, a scale is arranged on the front, and a heating sheet is fixedly installed inside.

[0009] A further improvement lies in that: an annular preheating zone is fixedly arranged at the top of the reactor.

[0010] A further improvement lies in that: a sampling pipe is connected between the reactor and the gas chromatograph.

[0011] A further improvement lies in that: a chromatographic column is fixedly installed inside the gas chromatograph.

[0012] A further improvement lies in that: a mass spectrometer is fixedly installed on the right side of the gas chromatograph.

[0013] A further improvement lies in that: a data acquisition and processor is fixedly installed at the top of the mass spectrometer. A vacuum ultraviolet light source with an ionization energy of 10.6 eV is fixedly installed inside. A time-of-flight mass analyzer is fixedly installed on the right side of the vacuum ultraviolet light source. An ion detector is fixedly installed on the right side of the time-of-flight mass analyzer.

[0014] A further improvement lies in that: a maintenance door is movably arranged on the front of the experimental mainframe.

[0015] A further improvement lies in that: a heat dissipation pipe is fixedly installed on the left side of the vaporization device.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] This device integrates experimental components, a feeding component, a gas chromatograph, and a time-of-flight mass analyzer, greatly improving the efficiency and smoothness of experimental operations. Compared with traditional decentralized experimental devices, this integrated design reduces the connection complexity and space occupation between experimental equipment, simplifies the operation process, and improves the overall experimental efficiency. The front of the device is equipped with a movable maintenance door, which facilitates users to conduct equipment inspections, cleaning, and maintenance during experiments. Through this design, the service life of the equipment can be effectively extended, and the failure downtime can be reduced. The setting of the heat dissipation pipe further optimizes the working state of the vaporization device, avoiding damage to the equipment caused by high temperature. The gas chromatograph and time-of-flight mass spectrometer (GC-TOFMS) equipped with this device can sample from the jet stirred reactor and conduct species identification and analysis. The GC-TOFMS system can not only identify various intermediate products and final products generated during the oxidation process with high sensitivity but also analyze their signal intensities. Through these accurate data, researchers can master the reaction process, understand the changes of species under different experimental conditions, and thus further optimize the reaction conditions. The feeding component of this device is well-designed, including a liquid flow controller, a vaporization device, a connecting pipe, etc., which can accurately control the temperature and flow rate of the reactants, ensuring the consistency of the oxidation reaction conditions. The heating sheet and scale setting of the liquid flow controller ensure the stable flow rate of the feeding liquid, avoiding the influence of flow rate fluctuations on the reaction results. At the same time, the annular preheating zone design at the top of the reactor helps to quickly increase the initial temperature of the reaction gas, further improving the reaction efficiency. Brief Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. The drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 Internal schematic diagram of the present invention;

[0020] Figure 2 Front cross-sectional view of the experimental chamber.

[0021] Attached drawing reference numerals: 1. Experimental mainframe; 2. Experimental chamber; 3. Reactor; 4. Jet stirred reactor; 5. Sampling tube; 6. Maintenance door; 7. K-type thermocouple; 8. Gas chromatograph; 9. Mass spectrometer; 10. Data acquisition and processor; 11. Flow controller; 12. Vaporization device; 13. Connecting pipe; 14. Heat dissipation pipe; 15. Feed inlet; 16. Scale; 17. Heating sheet; 18. Annular preheating zone; 19. Chromatographic column (HP-PLOT Q); 20. Vacuum ultraviolet light source (10.6 eV); 21. Time-of-flight mass analyzer; 22. Ion detector. Detailed implementation manners

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0023] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0024] See Figure 1 、 Figure 2 , the present invention discloses a device for species identification and analysis during the low-temperature oxidation of liquid fuels, including an experimental mainframe 1, an experimental component, and a feed component. A plurality of experimental components are fixedly installed inside the experimental mainframe 1, and a feed component is fixedly installed above. The reaction gas is introduced into the experimental mainframe through the feed component, and the reaction is carried out through the experimental component. The GC-TOFMS is used for species identification and analysis.

[0025] The experimental component includes an experimental chamber 2, a reactor 3, a jet stirred reactor 4, and a K-type thermocouple 7. A reactor 3 is fixedly installed in the upper left of the experimental chamber 2, and a jet stirred reactor 4 is fixedly installed inside the reactor 3. The jet stirred reactor 4 is arranged directly below the feed component. The jet stirred reactor 4 can effectively avoid the uneven distribution of gas or the insufficient contact of reactants, thereby improving the reaction rate and the uniformity of the reaction. A K-type thermocouple 7 is fixedly installed inside the jet stirred reactor 4 for accurately measuring and monitoring the temperature inside the reactor. A thermocouple is a commonly used temperature sensor, which measures the temperature through the thermoelectric potential generated at the joint of two different metal conductors.

[0026] A sampling tube 5 is connected to the outlet of the reactor 3, and a peristaltic pump is used to extract the gas. The other end of the sampling tube 5 is connected to a gas chromatograph 8. The sample is introduced into the chromatographic column (HP-PLOT Q) 19 in a splitless injection mode that is conducive to trace analysis. Through the adsorption and elution characteristics of different components in the column, the separation of the sample is achieved, providing pure components for subsequent mass spectrometry analysis, which helps with accurate identification and analysis. A mass spectrometer 9 is fixedly installed on the right side of the gas chromatograph 8. Inside the mass spectrometer 9, a vacuum ultraviolet light source 20 with an ionization energy of 10.6 eV is fixedly installed. On the right side of the vacuum ultraviolet light source 20, a time-of-flight mass analyzer 21 is fixedly installed. On the right side of the time-of-flight mass analyzer 21, an ion detector 22 is fixedly installed. By ionizing the sample and measuring the flight time of the ions, various compounds are accurately identified and analyzed. A data acquisition and processor 10 is fixedly installed above the mass spectrometer 9. The GC-TOFMS can not only highly sensitively identify various intermediate products and final products generated during the oxidation process, but also analyze their signal intensities. Through these accurate data, researchers can master the reaction process, understand the changes of species under different experimental conditions, and thus further optimize the reaction conditions.

[0027] The feeding assembly includes a liquid flow controller 11, a vaporization device 12, and a connecting pipe 13. The liquid flow controller 11 is fixedly installed on the left side at the top of the experimental mainframe 1. The vaporization device 12 is fixedly installed at the bottom of the liquid flow controller 11. The fuel is injected into the vaporization device 12 through the liquid flow controller 11. Inside the vaporization device 12, a heating sheet 17 is fixedly installed. The inside of the vaporization device 12 is heated by the heating sheet 17, and the temperature needs to be about 30 K higher than the boiling point of the liquid fuel. The right side of the vaporization device 12 is fixedly connected to the connecting pipe 13, and the other end of the connecting pipe 13 is connected to an oxygen tank. The gaseous fuel and the oxidant are mixed and then introduced into the reactor 3.

[0028] The top of the liquid flow controller 11 is provided with a feeding port 15, the front is provided with a scale 16, and the heating sheet 17 is fixedly installed inside. The liquid fuel is introduced into the liquid flow controller 11 through the feeding port 15, and the liquid flow is observed through the scale 16.

[0029] A circular preheating zone 18 is fixedly arranged at the top of the reactor 3, which can heat the inlet mixture in a short time to make the temperature and composition inside the reactor reach reliable uniformity.

[0030] A maintenance door 6 is movably arranged on the front of the experimental mainframe 1. Through the setting of the maintenance door 6, it is convenient to open the experimental mainframe 1 to use and maintain its internal components.

[0031] A heat dissipation tube 14 is fixedly installed on the left side of the vaporization device 12, and the used vaporization device 12 is dissipated heat through the heat dissipation tube 14.

[0032] Principle of use:

[0033] Use a liquid flow controller 11 to inject fuel into the vaporization device 12. After the fuel is vaporized, mix it with oxygen and dilution gas, and enter the jet stirring reactor 4 through a pipeline. A K-type thermocouple 7 is installed in the center of the jet stirring reactor 4 to monitor the reaction temperature. An annular preheating zone 18 is fixedly arranged at the top of the reactor 3, which can heat the inlet mixture in a short time to make the temperature and composition in the reactor reach reliable uniformity. Use a sampling tube 5 to sample at the outlet of the reactor. At the same time, use a peristaltic pump to extract the gas, and introduce the sample into the chromatographic column 19 in a splitless injection mode that is beneficial to trace analysis. Through the adsorption and elution characteristics of different components in the gas chromatographic column, the separation of the sample is achieved. In the mass spectrometer 9, by ionizing the sample and measuring the flight time of the ions, various compounds are accurately identified and analyzed. Finally, the experimental results are displayed on the data acquisition and processor 10.

[0034] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An apparatus for species identification and analysis in the low-temperature oxidation process of a liquid fuel, comprising an experimental mainframe (1), an experimental component, and a feeding component, characterized in that, Inside the experimental mainframe (1), multiple groups of experimental components are fixedly installed. Above the test components, a feeding component is fixedly installed. The experimental components include an experimental chamber (2), a reactor (3), a jet stirring reactor (4), a sampling tube (5), a K-type thermocouple (7), a gas chromatograph (8), a mass spectrometer (9), and a data acquisition and processor (10). Inside the upper left of the experimental chamber (2), a reactor (3) is fixedly installed. Inside the reactor (3), a jet stirring reactor (4) is fixedly installed. The jet stirring reactor (4) is arranged directly below the feeding component. Inside the jet stirring reactor (4), a K-type thermocouple (7) is fixedly installed. At the outlet of the reactor (3), a sampling tube (5) is connected. The other end of the sampling tube (5) is connected to the gas chromatograph (8). On the right side of the gas chromatograph (8), a mass spectrometer (9) is fixedly installed. Above the mass spectrometer (9), a data acquisition and processor (10) is fixedly installed.

2. The species identification and analysis device in the low-temperature oxidation process of a liquid fuel according to claim 1, wherein: The feeding component includes a liquid flow controller (11), a vaporization device (12), and a connecting pipe (13). On the left side of the top of the experimental mainframe (1), a liquid flow controller (11) is fixedly installed. At the bottom of the liquid flow controller (11), a vaporization device (12) is fixedly installed. Inside the vaporization device (12), a heating sheet (17) is fixedly installed. On the right side of the heating sheet (17), a connecting pipe (13) is fixedly connected. The other end of the connecting pipe (13) is connected to an oxygen tank.

3. The species identification and analysis device in the low-temperature oxidation process of a liquid fuel according to claim 2, characterized in that: At the top of the liquid flow controller (11), a feeding port (15) is provided. On the front of the feeding port (15), a scale (16) is provided.

4. An apparatus for species identification and analysis during the low-temperature oxidation of a liquid fuel according to claim 1, characterized in that: At the top of the reactor (3), an annular preheating zone (18) is fixedly provided.

5. The species identification and analysis device in the low-temperature oxidation process of a liquid fuel according to claim 1, characterized in that: Between the reactor (3) and the gas chromatograph (8), a sampling tube (5) is connected.

6. The species identification and analysis device in the low-temperature oxidation process of a liquid fuel according to claim 1, characterized in that: Inside the gas chromatograph (8), a chromatographic column (HP-PLOT Q) (19) is fixedly installed.

7. An apparatus for species identification and analysis during the low-temperature oxidation of a liquid fuel according to claim 1, characterized in that: On the right side of the gas chromatograph (8), a mass spectrometer (9) is fixedly installed.

8. An apparatus for species identification and analysis in the low-temperature oxidation of liquid fuel according to claim 7, characterized in that: Inside the mass spectrometer (9), a vacuum ultraviolet light source (20) with an ionization energy of 10.6 eV is fixedly installed. On the right side of the vacuum ultraviolet light source (10.6 eV) (20), a time-of-flight mass analyzer (21) is fixedly installed. On the right side of the time-of-flight mass analyzer (21), an ion detector (22) is fixedly installed.

9. The species identification and analysis device in the low-temperature oxidation process of a liquid fuel according to claim 1, characterized in that: On the front of the experimental mainframe (1), a maintenance door (6) is movably provided.

10. The species identification and analysis device in the low-temperature oxidation process of a liquid fuel according to claim 2, characterized in that: On the left side of the vaporization device (12), a heat dissipation pipe (14) is fixedly installed.

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