Catalytic pyrolysis combined in-situ neutron scattering sample environment equipment

Abstract

The utility model belongs to the technical field of scattering in-situ catalytic reaction, and particularly relates to in-situ neutron scattering sample environment equipment combining catalytic pyrolysis. The in-situ neutron scattering sample environment equipment comprises a neutron emission device, a heating device, a gas supply device and a sample table used for installing a sample tube, the sample table is installed on the heating device, two symmetrically-distributed fixing support sets are arranged in the sample table and used for fixing the sample tube, the neutron emission device is arranged in front of the sample table, and the gas supply device is arranged in front of the sample table. The neutron emitter emits neutron rays to a sample; the neutron scattering device is simple in structure, clear in principle, efficient, stable and capable of accurately controlling supply of reaction gas, heating temperature and exposure conditions of a catalyst sample so as to obtain accurate catalyst performance data, overcomes the defects of existing neutron scattering equipment in the aspects of gas supply and catalytic reaction environment control, and has a good application prospect. The requirements of complex in-situ catalytic reaction detection cannot be met.

Description

Technical Field

[0001] The utility model belongs to the technical field of scattering in-situ catalytic reaction, and in particular relates to an in-situ neutron scattering sample environment device combined with catalytic pyrolysis. Background Art

[0002] At present, neutron scattering technology plays a role that cannot be replaced by X-rays in research fields such as biology, life, and medicine. Spallation neutron sources and synchrotron radiation sources complement each other and have become one of the most important platforms for basic scientific research and new material development. However, existing neutron scattering characterization equipment is mostly used for the characterization of non-in-situ samples, and there is a lack of in-situ catalytic characterization sample environment equipment suitable for neutron scattering. Therefore, it is necessary to develop in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis to reveal the evolution process of key active sites of catalysts under different conditions and provide technical support for establishing a clear catalytic structure-activity relationship. Summary of the invention

[0003] In view of the shortcomings of existing neutron scattering equipment in gas supply and catalytic reaction environment control, which cannot meet the needs of complex in-situ catalytic reaction detection, the utility model aims to provide an in-situ neutron scattering sample environment equipment with simple structure, high efficiency, stability and safety, which is of great significance for catalytic science research.

[0004] The technical solution adopted to achieve the above-mentioned purpose is as follows: an in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis, the in-situ neutron scattering sample environment equipment comprising a neutron emission device, a heating device, a gas supply device and a sample stage for mounting a sample tube, the sample stage being mounted on the heating device, and having two groups of symmetrically distributed fixed bracket groups arranged inside the heating device for fixing the sample tube, and the neutron emission device being arranged in front of the sample stage for emitting neutron rays to the sample.

[0005] The inlet end of the in-situ neutron scattering sample environment equipment is connected to the gas supply device through a pipeline.

[0006] The in-situ neutron scattering sample environment equipment also includes a control system, which is communicatively connected with the temperature detection device, the heating device, and the gas supply device.

[0007] The gas supply device comprises a gas cylinder for providing gas.

[0008] The sample tube is made of quartz glass and is used to hold catalyst powder samples.

[0009] The sample tube is provided with a temperature detection device.

[0010] The inner diameter of the sample tube ranges from 5 mm to 10 mm, and the wall thickness ranges from 0.08 mm to 2 mm.

[0011] The gas supply device also includes a pressure reducing valve, a pressure sensor and a flow meter which are sequentially arranged along the flow direction of the gas flow.

[0012] The in-situ neutron scattering sample environment equipment also includes a cooling device, which is a circulating water cooling system, located at the upper and lower ends of the heating.

[0013] Two pipeline plugging pieces are arranged in the sample tube at intervals to form a sample reaction zone for containing and exposing the catalyst powder sample.

[0014] The beneficial effects of the technical solution are as follows: the utility model provides an in-situ neutron scattering sample environment device combined with catalytic pyrolysis, which has a simple structure and clear principle, and can accurately control the supply of reaction gas, heating temperature and exposure conditions of catalyst samples, so as to obtain accurate catalyst performance data, and solves the shortcomings of existing neutron scattering equipment in gas supply and catalytic reaction environment control, and cannot meet the needs of complex in-situ catalytic reaction detection. The utility model is an efficient, stable and safe in-situ neutron scattering sample environment device, which is of great significance for catalytic scientific research; more specifically, the sample tube is made of quartz glass, which has excellent heat resistance and chemical stability; a fixed bracket group is arranged inside the sample table for firmly fixing the sample tube; the gas supply device includes a pressure reducing valve, a pressure sensor and a flow meter to ensure stable supply and precise control of the gas; the heating device adopts an electrically heated high-temperature furnace, which has the characteristics of rapid heating and uniform heating; the cooling device adopts a circulating water cooling system to ensure the stable operation of the high-temperature furnace and extend its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure logic principle of the utility model when used in a neutron scattering in-situ catalytic reaction detection experiment;

[0016] Figure 2 It is a three-dimensional structural schematic diagram of the medium and high temperature furnace reaction system of the utility model;

[0017] Figure 3 It is a front view of the medium and high temperature furnace reaction system of the utility model;

[0018] Figure 4 It is a top view of the medium and high temperature furnace reaction system of the utility model;

[0019] Figure 5 This is a plan view of the medium and high temperature furnace reaction system of the utility model;

[0020] Figure 6 It is a schematic diagram of the structure of the sample rack in the utility model;

[0021] Notes on the accompanying drawings: 1. Gas cylinder; 2. Gas purifier; 3. Pressure sensor; 4. Mass flow controller; 5. Sample rack; 6. High-temperature furnace reaction system; 7. Water-cooled wall; 8. Heating plate; 9. Neutron beam window; 10. Vacuum pump interface; 11. Cooling water interface; 12. Power interface; 13. Armored thermocouple; 14. Sample tube; 15. Sample table. DETAILED DESCRIPTION

[0022] like Figure 1-6 As shown, the specific implementation mode of the utility model is described in detail below in conjunction with the drawings of the specification: an in-situ neutron scattering sample environment device combined with catalytic pyrolysis is mainly used for neutron scattering in-situ catalytic reaction detection. The in-situ neutron scattering sample environment device includes a neutron emission device, a heating device, a gas supply device and a sample table for mounting a sample tube. The sample table is installed on the heating device, and two groups of symmetrically distributed fixed bracket groups are arranged inside the heating device for fixing the sample tube. The neutron emission device is arranged in front of the sample table for emitting neutron rays to the sample.

[0023] In this embodiment, the sample tube 14 is used to hold a catalyst powder sample; the sample tube 14 is installed on the sample table 15, and a temperature detection device is provided on the sample table 15; the heating device is used to install the sample table 15, and the heating device can heat the sample table 15 and the sample tube 14; the neutron emission device is arranged in front of the sample table 15, and is used to vertically emit neutron rays to the in-situ reaction plug-in; the gas supply device, the gas supply device includes a gas cylinder 1, and the gas cylinder 1 is connected to the inlet end of the in-situ reaction plug-in through a pipeline, and is used to provide gas to the in-situ reaction plug-in; a pressure reducing valve, a pressure sensor 3, and a flow meter are sequentially arranged between the gas storage bottle and the sample tube 14 along the flow direction of the gas flow; the control system is communicatively connected with the temperature detection device, the heating device, the flow meter, and the gas supply device.

[0024] In this embodiment, the sample tube 14 is made of quartz glass; the inner diameter of the sample tube 14 is 5mm-10mm, and the wall thickness is 0.08-2mm; the lower end of the sample tube 14 is sealed with a quartz sieve plate, and the quartz sieve plate has a plurality of through holes with a diameter of 0.5mm-2mm; two groups of symmetrically distributed fixed bracket groups are arranged inside the sample stage 15, each group of fixed bracket groups includes three fixed brackets with equal distances, and the six fixed brackets are provided with sample tube 14 jacks, temperature detector jacks and two gas flow holes, and the sample tube 14 and the temperature detector jacks pass through the sample tube 14 jacks and temperature detector jacks on the six fixed brackets in turn; the outer shell of the sample stage 15 is made of quartz glass with an inner diameter of 30mm-40mm and a wall thickness of 1mm-2mm m; the upper end of the sample table 15 is equipped with a temperature detection device socket, the interface diameter is 3mm~5mm, and a quartz glass cover for installing the temperature detection device is provided; the temperature testing device and the heating device are respectively an armored thermocouple 13 and an electric heating high temperature furnace; the outer shell of the electric heating high temperature furnace is made of stainless steel or vanadium; the electric heating high temperature furnace has a diameter of 380mm and a height of 727mm; the electric heating high temperature furnace cooling device, the cooling device is a circulating water cooling system, located at the upper and lower ends of the high temperature furnace cooling device; two pipe plugging parts are arranged in the sample tube 14 at intervals, and a sample reaction zone is formed between the two pipe plugging parts, the catalyst powder sample is placed in the sample reaction zone, and the sample reaction zone is used to be exposed to the exposure zone; wherein the pipe plugging part includes a liner and quartz wool.

[0025] When conducting the experiment, the catalyst powder sample to be tested is loaded into the sample tube 14, and the sample tube 14 is installed on the sample table; the neutron ray emission device, the temperature detection device, the sample heating device and the gas supply device are started by the control device; the reaction gas is introduced into the sample tube 14 through the gas supply device; the heating temperature of the sample heating device and the composition of the gas supplied by the gas supply device are changed to test the neutron scattering spectrum data under different temperature conditions and atmosphere conditions; wherein, the gas cylinder 1, the filter, the solenoid valve, the pressure reducing valve, the needle valve, the gas purifier 2, and the one-way valve are connected in sequence through a 1 / 8 inch steel pipe; if there are multiple gases, the parallel number of the gas cylinder 1, the filter, the solenoid valve, the pressure reducing valve, the needle valve, and the gas purifier 2 can be increased through a three-way or a four-way; the pressure sensor 3, the mass flow controller 4, the needle valve, the safety valve, and the sample tube 14 are connected in sequence through a 1 / 8 inch steel pipe; the gas cylinder 1 is the reaction The reaction gas required for the in-situ catalytic reaction is provided; the pressure sensor 3, the combustible gas alarm in the control cabinet, the mobile combustible gas detector and the pneumatic device are connected through the circuit, and the gas outlet at the upper end of the sample table 15 is connected to the tail gas treatment system through a 1 / 8 inch steel pipe; in the implementation, the reaction gas flows through the filter, solenoid valve, pressure reducing valve, needle valve, gas purifier 2, and one-way valve in turn through the gas control system and then flows into the mass flow meter with the parallel gas path; the material of the sample tube 14 is quartz glass, with a wall thickness of 0.8-1.2 mm and an outer diameter of 12 mm. The reacted gas passes through the gas outlet at the upper end of the sample table 15, and the reacted gas flows into the sample tube 14 and reacts with the catalyst. The reacted gas flows out of the reaction in-situ test device and flows into the tail gas treatment system. When the combustible gas leaks and the pressure is too high, the gas delivery is closed by the pneumatic device; in this embodiment, the control system is connected to each device for communication to realize automatic control and data acquisition. The heating temperature, gas flow rate and composition can be accurately adjusted by the control system to meet the needs of different catalytic reaction conditions.

[0026] During use, first, the catalyst powder sample is loaded into the sample tube 14, and the sample tube is installed on the sample table 15. Then the neutron ray emission device, temperature detection device, heating device and gas supply device are started, and the reaction gas is introduced into the sample tube through the gas supply device, and the heating temperature of the heating device and the composition of the gas supplied by the gas supply device are adjusted. In this process, the neutron scattering data will be recorded and analyzed in real time to reveal the performance changes of the catalyst under different reaction conditions; the utility model realizes the demand for neutron scattering in-situ catalytic reaction detection by providing an efficient, stable and safe in-situ neutron scattering sample environment device. The device can accurately control the supply of reaction gas, heating temperature and exposure conditions of catalyst samples, so as to obtain accurate catalyst performance data. This utility model is of great significance to the research and industrial application of catalytic science.

Claims

1. An in-situ neutron scattering sample environment device combined with catalytic pyrolysis, characterized in that: The in-situ neutron scattering sample environment equipment comprises a neutron emission device, a heating device, a gas supply device and a sample stage (15) for mounting a sample tube (14). The sample stage (15) is mounted on the heating device and has two groups of symmetrically distributed fixed brackets arranged inside the heating device for fixing the sample tube (14). The neutron emission device is arranged in front of the sample stage (15) for emitting neutron rays to the sample.

2. The in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis according to claim 1, characterized in that: The inlet end of the in-situ neutron scattering sample environment equipment is connected to the gas supply device through a pipeline.

3. The in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis according to claim 1, characterized in that: The in-situ neutron scattering sample environment equipment also includes a control system, which is communicatively connected with the temperature detection device, the heating device, and the gas supply device.

4. The in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis according to claim 1, characterized in that: The gas supply device comprises a gas cylinder (1) for providing gas.

5. The in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis according to claim 1, characterized in that: The sample tube (14) is made of quartz glass and is used to hold catalyst powder samples.

6. The in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis according to claim 1, characterized in that: The sample tube (14) is provided with a temperature detection device.

7. The in-situ neutron scattering sample environment device combined with catalytic pyrolysis according to claim 1, 5 or 6, characterized in that: The inner diameter of the sample tube (14) ranges from 5 mm to 10 mm, and the wall thickness ranges from 0.08 mm to 2 mm.

8. The in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis according to claim 1, characterized in that: The gas supply device also includes a pressure reducing valve, a pressure sensor (3) and a flow meter which are arranged in sequence along the flow direction of the gas flow.

9. The in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis according to claim 1, characterized in that: The in-situ neutron scattering sample environment equipment also includes a cooling device, which is a circulating water cooling system, located at the upper and lower ends of the heating.

10. The in-situ neutron scattering sample environment equipment combined with catalytic pyrolysis according to claim 1, characterized in that: Two pipeline plugging pieces are arranged at intervals in the sample tube (14) to form a sample reaction zone for containing and exposing the catalyst powder sample.

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