CN113702413A - Heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research and using method - Google Patents
Heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research and using method Download PDFInfo
- Publication number
- CN113702413A CN113702413A CN202111007232.6A CN202111007232A CN113702413A CN 113702413 A CN113702413 A CN 113702413A CN 202111007232 A CN202111007232 A CN 202111007232A CN 113702413 A CN113702413 A CN 113702413A
- Authority
- CN
- China
- Prior art keywords
- reaction
- gas
- catalyst
- valve
- activation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N24/00—Investigating or analyzing materials by the use of nuclear magnetic resonance, electron paramagnetic resonance or other spin effects
- G01N24/10—Investigating or analyzing materials by the use of nuclear magnetic resonance, electron paramagnetic resonance or other spin effects by using electron paramagnetic resonance
Landscapes
- Physics & Mathematics (AREA)
- High Energy & Nuclear Physics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention discloses a heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research, which consists of a vacuum pump, a cooling device, a connecting pipeline and a reaction tank, wherein the vacuum pump comprises the following four parts: the cooling device consists of a cold hydrazine and a liquid nitrogen tank; the reaction tank consists of a double-layer glass sleeve and a heating furnace, the double-layer glass sleeve is convenient to disassemble, and the double-layer glass sleeve can be directly placed in a resonant cavity of an electron paramagnetic resonance spectrometer for characterization test; the connecting pipeline comprises a vacuum gauge, a three-way valve, a ball valve, a filter and a back pressure valve, and can directly connect the reaction tank with the activation/reaction device and meet the activation/reaction requirements of the catalyst. The device can be used together with various characterization instruments, and provides powerful support for activating the catalyst and carrying out in-situ/quasi-in-situ characterization of catalytic reaction.
Description
Technical Field
The invention relates to the technical field of heterogeneous catalyst activation/reaction, in particular to a heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research and a using method thereof, which can be applied to in-situ and quasi-in-situ characterization of heterogeneous catalysts.
Background
Catalysts are widely used in modern chemical industry, petroleum processing industry, energy, pharmaceutical industry, environmental protection and the like. In chemical industrial production, the catalytic process accounts for more than 80% of the whole chemical process. Heterogeneous catalysts dominate the manufacturing process of chemical products due to their advantage of easy separation from the product. In the practical application process of the supported heterogeneous catalyst, activation is usually required to remove surface adsorbed substances, reduce the valence state of metal and the like so as to achieve the effect of exposing active sites and improve the reaction activity.
Currently, the catalyst activation method commonly used in industry is to perform calcination or further reduction, oxidation, sulfidation, hydroxylation, dehydroxylation, etc. on the catalyst at a higher temperature, thereby converting a passive catalyst or a catalyst precursor into an active catalyst. For part of catalysts, only substances adsorbed on the surface need to be removed in the activation process, active sites are exposed, the cost is high by adopting a mode of introducing gas for heating and activating, waste gas is easy to generate, and the method is not a preferred scheme. In addition, if the activated catalyst is transferred to a reaction device without contacting air, the activated catalyst needs to be operated in a glove box, the operation is complex, the effect is difficult to ensure, and the catalyst activation/reaction integrated device can effectively solve the problem.
Disclosure of Invention
The technical problem to be solved is as follows:
the heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research, which is designed by the invention, can simultaneously meet two activation ways of vacuum activation and gas heating activation, and is suitable for the activation requirements of various catalysts; the method can realize that the catalyst directly participates in the reaction process after being activated, and the reaction tank can carry out electron paramagnetic resonance in-situ/quasi-in-situ test. The device can be connected with an online testing instrument, such as a Gas Chromatography (GC) or an online Mass Spectrometer (MS), and can directly characterize the reacted product, complete a whole set of catalyst activation, reaction and characterization processes, greatly shorten the time required by experiments, simplify the operation steps, and avoid the reduction or inactivation of the catalytic performance caused by the repeated contact of the catalyst and air.
The technical scheme is as follows:
a heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research is characterized in that: the heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research is composed of a vacuum pump, a cooling device, a connecting pipeline and a reaction tank. The cooling device consists of a liquid nitrogen tank and a cold trap, and the upper part of the pipe is provided with an air release valve for balancing the air pressure in the pipe after vacuum activation; the adsorbed gas and water removed in the vacuum activation process of the catalyst are condensed into the glass tube through the cooling device, so that volatile substances are prevented from entering the vacuum pump to damage the pump body. The connecting pipeline is composed of a needle valve, a ball valve, a vacuum gauge, a three-way valve, a one-way valve, a filter, a back pressure valve and a temperature measuring point, and partial pipelines need to be insulated to ensure that reaction gas and products cannot be condensed in the pipelines. The connecting pipeline connects the gas distribution system, the vacuum pump and the reaction tank, and the three-way valve can be used for flexibly switching to a catalyst activation or reaction path. The reaction tank main body is a double-layer glass sleeve pipe, and a heating furnace with a quartz window is configured, so that different requirements of the light/heat catalytic reaction characterization of the catalyst under vacuum activation, ventilation body activation and quasi-in-situ conditions and the light/heat catalytic reaction characterization under the in-situ conditions can be met.
As a preferred technical scheme of the invention, the electron paramagnetic resonance research heterogeneous catalyst activation/reaction device has two operation modes when being used for catalyst activation: a vacuum activation mode and a vent activation mode. The vacuum activation mode is to remove adsorbates on the surface of the catalyst to expose active sites by using high vacuum condition and high temperature as assistance, thereby realizing the activation of the catalyst; the aeration body activation is to connect the gas distribution system with the reaction tank, and the target gas is supplemented with high temperature condition to meet the specific gas activation mode requirement needed by some catalysts; meanwhile, the gas distribution system is connected with the reaction tank and can also be used as a reaction device required by the catalyst in situ/quasi-in situ characterization, the double-layer glass sleeve in the reaction tank can be directly placed in a resonance cavity of an electron paramagnetic resonance spectrometer for catalyst characterization, and the evacuation pipeline can also be connected with other characterization instruments, such as a Gas Chromatography (GC) or an online Mass Spectrometer (MS) for online test of reaction products.
As a preferred technical scheme of the invention: the cooling device selects high borosilicate glass as a cold trap material, two ends of the cooling device are connected with a vacuum pump and a three-way valve through a vacuum corrugated pipe, and the right side of the cooling device is connected with a vacuum gauge to observe the internal vacuum degree of the system; the air release valve is used for balancing the air pressure of the system after the vacuum activation operation is finished, so that the device can be conveniently switched to a catalyst reaction path, and the activated catalyst is directly subjected to in-situ/quasi-in-situ characterization.
As a preferred technical scheme of the invention: in the reaction tank, a double-layer glass sleeve as a reaction tank main body is made of quartz, so that the reaction tank is convenient to illuminate, has an outer diameter of less than or equal to 10mm, and can be directly placed in a resonant cavity of an electron paramagnetic resonance spectrometer for characterization; the wall thickness of the glass sleeve is adjusted according to the internal pressure of an actual system. The two ends of the double-layer glass sleeve are provided with filters to prevent the catalyst in the sleeve from blowing out along with the air flow to block pipelines and valves, and meanwhile, the ball valve is additionally arranged, so that the reaction tank is convenient to disassemble and the vacuum or gas environment in the reaction pipe is kept. The back end of the gas outlet pipeline is provided with a one-way valve to prevent gas from flowing back and polluting the catalyst. The heating furnace with the quartz window arranged in the reaction tank can be made into an independent heating furnace for respectively heating the double-layer glass sleeves; the furnace can also be manufactured into an integral hearth, and a plurality of glass sleeves are heated at the same time, and can be designed according to experimental requirements.
As a preferable aspect of the present invention, the connection line is characterized in that: the three-way valve is connected with the cooling device and the reaction tank, and the ball valve is assembled at the outlet of the gas distribution system, so that the gas flow generated by the gas distribution system can be conveniently controlled to slowly enter the reaction tank in a vacuum state, and the catalyst is prevented from being blown away from a detection area from the bottom of the double-layer glass sleeve by overlarge gas flow when the valve 1-2 is opened. In addition, a three-way valve is additionally arranged at the front end of the reaction tank and is directly communicated with an emptying pipeline, so that the gas distribution proportion can be conveniently checked before the reaction starts through an analytical instrument such as a gas chromatograph. Filters are designed at two ends of the back pressure valve with the temperature measuring point to prevent solid particles from entering the back pressure valve or downstream detection equipment to cause damage to accessories; the ball valve and the needle valve of the back pressure valve bypass are used for quickly discharging gas in the system.
As a preferable aspect of the present invention, the connection line is characterized in that: the gas distribution system is connected with the reaction tank, and then the gas paths connected with the emptying pipeline are all heat-insulating pipelines, the temperature is not lower than 130 ℃, on one hand, the condensation of partial low-boiling-point raw material gas or product is prevented, and on the other hand, the preheating of contact catalyst gas is facilitated.
As a preferred technical scheme of the invention: the vacuum degree of the vacuum pump can reach less than 0.01 mbar; the double-layer glass sleeve in the reaction tank can bear 5MPa of pressure at most, and the sealing joint is made of nonmagnetic material; the heating furnace adopts programmed heating, and can meet the heating condition from room temperature to 800 ℃.
A use method of a heterogeneous catalyst vacuum activation/reaction device for electron paramagnetic resonance research is characterized by comprising the following steps:
the first step is as follows: adding a catalyst into the double-layer glass sleeve, and if an electron paramagnetic resonance test is required, filling the sample to a height within 4.0 cm; connecting the pipelines in sequence, and placing the double-layer glass sleeve filled with the catalyst in a heating furnace.
The second step is that: switching a three-way valve 4-1 to a cooling device to be communicated with the reaction tank, and switching a three-way valve 4-2 to an air inlet pipeline to be communicated with the reaction tank; closing a ball valve 1-4 at the rear part of the reaction tank, opening a vacuum pump under the condition of ensuring that an air release valve on a cooling device is closed, opening the ball valve 1-1, slowly opening the ball valve 1-3 for vacuumizing, checking the indication number of a vacuum gauge to ensure that the device system has no air leakage phenomenon, and activating the vacuum for a certain time.
The third step: and under the condition that the ball valve 1-2 behind the gas distribution system is closed, switching the three-way ball valve 4-1 to the gas distribution system to be communicated with the reaction tank, opening the air pressure of a balance pipeline of the air release valve, closing the vacuum pump, and carrying out the subsequent catalyst reaction process.
The fourth step: under the condition that the three-way valve 4-2 is directly communicated with the gas distribution system and the rear emptying pipe, gas is prepared according to experimental requirements, the ball valve 1-2 is opened, a small amount of gas is used for flushing the pipeline, the ball valve 1-5 and the back pressure valve are closed after flushing is completed, then the ball valve 1-2 is closed, and the three-way valve 4-2 is switched to be communicated with the gas distribution system and the reaction tank.
The fifth step: opening ball valves 1-2, 1-3 and 1-4 in sequence, adjusting a back pressure valve to a required pressure, enabling the gas to flow through a reaction tank, setting the temperature of a heating furnace to a temperature required by an experiment, and carrying out catalytic reaction.
And a sixth step: if in-situ electron paramagnetic resonance testing is to be carried out, directly placing a double-layer glass sleeve in a reaction tank into a resonant cavity of an electron paramagnetic resonance spectrometer, and carrying out in-situ testing by utilizing a self-carrying heating device of an instrument; if the quasi-in-situ electron paramagnetic resonance test is to be carried out, the double-layer glass sleeve is placed in a heating furnace for reaction, after the reaction is finished, the ball valves 1-3 and 1-4 are closed, the connecting parts at the upper ends of the ball valves 1-3 and 1-4 are disconnected, and then the double-layer glass sleeve is taken out and placed in a resonant cavity for testing. The back end of the emptying pipe can be connected with a Gas Chromatograph (GC) or an online Mass Spectrometer (MS) to test reaction products.
A method for using a catalyst gas heating activation/reaction device is characterized by comprising the following steps:
the first step is as follows: adding a catalyst into the double-layer glass sleeve, and if an electron paramagnetic resonance test is required, filling the sample to a height within 4.0 cm; the double-layer glass sleeve filled with the catalyst is placed in a heating furnace according to the connection pipeline.
The second step is that: the three-way valves 4-1 and 4-2 are communicated with the gas distribution device and the reaction tank, the ball valves 1-3 and 1-4 are opened, the valves 1-5 and 14 are opened, and the back pressure valve is opened to enable the required gas to flow through the reaction tank. And setting the temperature of the heating furnace according to the activation requirement to activate the catalyst.
The third step: and after activation, closing a back pressure valve and ball valves 1-5, 1-4, 1-3 and 1-2 in sequence, and preparing gas for catalytic reaction testing. If the gas distribution system needs to change gas, the three-way valve 4-2 is switched to the gas distribution system to be directly communicated with an emptying pipeline, the ball valve 1-2, the back pressure valve and the valves 1-5 and 14 are opened, the pipeline is flushed by reaction gas for a plurality of times, and then subsequent catalytic reaction and related characterization tests are carried out.
The fourth step: and after the purging is finished, closing the valve 1-5 and the back pressure valve, closing the ball valve 1-2, and switching the three-way valve 4-2 to communicate the gas distribution system and the reaction tank.
The fifth step: opening ball valves 1-2, 1-3 and 1-4 in sequence, adjusting a back pressure valve to a required pressure, enabling the gas to flow through a reaction tank, setting the temperature of a heating furnace to be required by the experiment, and carrying out catalytic reaction.
And a sixth step: if in-situ electron paramagnetic resonance testing is to be carried out, directly placing a double-layer glass sleeve in a reaction tank into a resonant cavity of an electron paramagnetic resonance spectrometer, and carrying out in-situ testing by utilizing a self-carrying heating device of an instrument; if the quasi-in-situ electron paramagnetic resonance test is to be carried out, the double-layer glass sleeve is placed in a heating furnace for reaction, after the reaction is finished, the ball valves 1-3 and 1-4 are closed, the connection of the upper ends of the ball valves 1-3 and 1-4 is disconnected, and then the double-layer glass sleeve is taken out and placed in a resonant cavity for testing. The back end of the emptying pipe can be connected with a Gas Chromatograph (GC) or an online Mass Spectrometer (MS) to test reaction products.
Has the advantages that:
1. the method has the advantages of considering both the vacuum activation operation and the gas heating activation operation of the catalyst, avoiding the problem of higher cost of heating and activating part of the catalyst by using gas, simplifying the operation and simultaneously improving the operation cost performance.
2. The invention can directly introduce the reaction gas to the catalyst for reaction after the catalyst is activated, thereby avoiding the complex step of transferring the activated catalyst to the reaction tank and simplifying the catalytic reaction process.
3. The invention can be used for in-situ/quasi-in-situ electron paramagnetic resonance testing, and overcomes the defects that an electron paramagnetic resonance spectrometer cannot be filled with gas and has insufficient pressure resistance in the in-situ characterization process.
4. The invention can be connected with other characterization instruments after the test to test the catalytic reaction product on line, and is a set of complete catalytic activation/reaction/test device.
Drawings
FIG. 1: is a schematic structural diagram of the heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research.
Description of reference numerals: 1. the device comprises a ball valve, a gas release valve, a vacuum gauge, a three-way valve, a cold trap, a liquid nitrogen tank, a filter, a catalyst, a check valve, a double-layer glass sleeve, a heating furnace with a quartz window, a back pressure valve, a temperature measuring point, a needle valve and a valve, wherein the ball valve is 2, the gas release valve is 3, the vacuum gauge is 4, the three-way valve is 5, the cold trap is 6, the liquid nitrogen tank is 7, the filter is 8, the catalyst is 9, the check valve is 10, the double-layer glass sleeve is 11, the heating furnace with the quartz window is 12, the back pressure valve is 13, the temperature measuring point is 14.
Detailed Description
The following examples are given by way of illustration of the present invention and are not to be construed as limiting the present invention and alterations and modifications of the methods, procedures or conditions of the present invention may be made without departing from the spirit and scope of the invention.
Furthermore, those skilled in the art will appreciate that the drawings are provided solely for the purposes of illustrating the invention, features and advantages thereof, and do not contain all of the component configurations and connections of the present invention.
As shown in FIG. 1, the heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research is composed of a vacuum pump, a cooling device, a connecting pipeline and a reaction tank. The cooling device consists of a liquid nitrogen tank 6 and a cold trap 5, and an air release valve 2 is arranged at the upper part of the pipe and used for balancing the air pressure in the pipe after the vacuum activation is finished; the gas and water adsorbed on the catalyst removed in the vacuum activation process are condensed in the cold trap through the cooling device, so that volatile substances are prevented from entering the vacuum pump to damage the pump body. The connecting pipeline is composed of a ball valve 1, a vacuum gauge 3, a three-way valve 4, a filter 7, a one-way valve 9, a back pressure valve 12, a temperature measuring point 13 and a needle valve 14, and partial pipelines need to be insulated to ensure that gas cannot be condensed in the pipelines. The connecting pipeline connects the gas distribution system, the vacuum pump and the reaction tank, and the three-way valve 4 can be used for flexibly switching to a catalyst activation or reaction path. The reaction tank main body is a double-layer glass sleeve 10, and a heating furnace 11 with a quartz window is configured, so that different requirements of the light/heat catalytic reaction characterization of the catalyst under vacuum activation, ventilation activation and quasi-in-situ conditions and the light/heat catalytic reaction characterization under the in-situ conditions can be met.
The heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research has two operation modes when being used for catalyst activation: a vacuum activation mode and a vent heating activation mode. The vacuum activation mode is to remove adsorbates on the surface of the catalyst to expose active sites by using high vacuum condition and high temperature as assistance, thereby realizing the activation of the catalyst; the heating and activation of the ventilation body is to connect the gas distribution system with the part of the reaction tank, and to assist the high temperature condition with the target gas, so as to meet the specific gas activation mode requirement needed by some catalysts; meanwhile, the gas distribution system is connected with the reaction tank and can be used as a reaction device required by the catalyst in-situ/quasi-in-situ characterization, and the double-layer glass sleeve 10 in the reaction tank can be directly placed in a resonant cavity of an electron paramagnetic resonance spectrometer for catalyst characterization; in addition, the evacuation line can be connected to other analytical instruments, such as Gas Chromatography (GC) or online Mass Spectrometry (MS) for in situ characterization of the reaction gas products.
The cooling device is characterized in that: selecting high borosilicate glass as a cold trap 5 material, connecting two ends of the cold trap with a vacuum pump and a three-way valve 4-1 through a vacuum corrugated pipe, and connecting a vacuum gauge 3 on the right side to observe the internal vacuum degree of the system; the air release valve 2 is used for balancing the system air pressure after the vacuum activation operation is finished (the device connection mode needs to be switched to a catalyst reaction path first), so that the oil pumping suck-back is avoided.
The reaction tank is characterized in that: the double-layer glass sleeve 10 serving as the reaction tank main body is made of quartz, is convenient for illumination, has an outer diameter of less than or equal to 10mm, and can be directly placed in a resonant cavity of an electron paramagnetic resonance spectrometer for catalyst characterization; the wall thickness of the glass sleeve is adjusted according to the internal pressure of an actual system. Two ends of the double-layer glass sleeve 10 are provided with filters 7-1 and 7-2 to prevent the catalyst in the sleeve from blowing out with air flow to block pipelines and valves, and ball valves 1-3 and 1-4 are additionally arranged to facilitate the disassembly of a reaction tank and maintain the vacuum or gas environment in the reaction pipe. The back end of the gas outlet pipeline is provided with a one-way valve 9 to prevent gas from flowing back and polluting the catalyst. The heating furnace 11 having the quartz window may be made as an independent heating furnace, which heats the double-glass sleeve 10, respectively; the furnace can also be manufactured into an integral hearth, and a plurality of glass sleeves are heated at the same time, and can be designed according to experimental requirements.
The connecting pipeline is characterized in that: the three-way valve 4-1 is connected with the cooling device and the reaction tank, and the ball valve 1-2 is assembled at the outlet of the gas distribution system, so that the gas flow generated by the gas distribution system can be controlled to slowly enter the reaction tank in a vacuum state, and the catalyst is prevented from being blown away from a detection area from the bottom of the double-layer glass sleeve by overlarge gas flow when the valve 1-2 is opened. In addition, a three-way valve 4-2 is additionally arranged at the front end of the reaction tank and is directly communicated with an emptying pipeline, so that the gas ratio can be conveniently checked before the reaction starts (through online detection instruments such as an online gas chromatograph). Both ends of a back pressure valve 12 with a temperature measuring point 13 are provided with filters 7-3 and 7-4 to prevent solid particles from entering the back pressure valve or a downstream detecting instrument to cause damage to accessories; ball valves 1-5 and needle valve 14 by-passing back pressure valve 12 are used for rapid pressure relief of the reaction system. The gas distribution system is connected with the reaction tank, and then the gas paths connected with the emptying pipeline all adopt heat-insulating pipelines, the temperature is not lower than 130 ℃, on one hand, in order to prevent the condensation of part of low-boiling-point raw material gas or products, on the other hand, the reaction gas is convenient to preheat.
The heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research is characterized by comprising the following parameters: the vacuum degree of the vacuum pump can reach less than 0.01 mbar; the double-layer glass sleeve 10 in the reaction tank can bear 5MPa of pressure at most, and the sealing joint is made of nonmagnetic materials; the heating furnace 11 adopts programmed heating, and can meet the heating condition from room temperature to 800 ℃.
The using method of the catalyst vacuum activation/reaction device comprises the following steps:
the first step is as follows: adding a catalyst into the double-layer glass sleeve, and if an electron paramagnetic resonance test is required, filling the sample to a height within 4.0 cm; connecting the pipelines in sequence, and placing the double-layer glass sleeve filled with the catalyst in a heating furnace.
The second step is that: switching a three-way valve 4-1 to a cooling device to be communicated with the reaction tank, and switching a three-way valve 4-2 to an air inlet pipeline to be communicated with the reaction tank; closing a ball valve 1-4 at the rear part of the reaction tank, opening a vacuum pump under the condition of ensuring that an air release valve on a cooling device is closed, opening the ball valve 1-1, slowly opening the ball valve 1-3 for vacuumizing, checking the indication number of a vacuum gauge to ensure that the device system has no air leakage phenomenon, and activating the vacuum for a certain time.
The third step: and under the condition that the ball valve 1-2 behind the gas distribution system is closed, switching the three-way ball valve 4-1 to the gas distribution system to be communicated with the reaction tank, opening the air pressure of a balance pipeline of the air release valve, closing the vacuum pump, and carrying out the subsequent catalyst reaction process.
The fourth step: under the condition that the three-way valve 4-2 directly communicates the gas distribution system with the rear evacuation pipe, pipeline purging is needed as an experiment, the ball valve 1-2 is opened, a small amount of gas is used for flushing the pipeline (wherein the needle valve 14 always keeps a small opening degree), the ball valve 1-5 and the back pressure valve are closed after flushing is finished, then the ball valve 1-2 is closed, and the three-way valve 4-2 is switched to communicate the gas distribution system with the reaction tank.
The fifth step: opening ball valves 1-2, 1-3 and 1-4 in sequence, adjusting a back pressure valve to a required pressure, enabling the gas to flow through a reaction tank, setting the temperature of a heating furnace to a temperature required by an experiment, and carrying out catalytic reaction.
And a sixth step: if in-situ electron paramagnetic resonance testing is to be carried out, directly placing a double-layer glass sleeve in a reaction tank into a resonant cavity of an electron paramagnetic resonance spectrometer, and carrying out in-situ testing by utilizing a self-carrying heating device of an instrument; if the quasi-in-situ electron paramagnetic resonance test is to be carried out, the double-layer glass sleeve is placed in a heating furnace for reaction, after the reaction is finished, the ball valves 1-3 and 1-4 are closed, the connecting parts at the upper ends of the ball valves 1-3 and 1-4 are disconnected, and then the double-layer glass sleeve is taken out and placed in a resonant cavity for testing. The back end of the emptying pipe can be connected with a Gas Chromatograph (GC) or an online Mass Spectrometer (MS) to test reaction products.
The using method of the catalyst gas heating activation/reaction device comprises the following steps:
the first step is as follows: adding a catalyst into the double-layer glass sleeve, and if an electron paramagnetic resonance test is required, filling the sample to a height within 4.0 cm; the double-layer glass sleeve filled with the catalyst is placed in a heating furnace according to the connection pipeline.
The second step is that: the three-way valves 4-1 and 4-2 are communicated with the gas distribution device and the reaction tank, the ball valves 1-3 and 1-4 are opened, the valves 1-5 and 14 are opened (wherein the needle valve 14 always keeps a small opening degree), and the back pressure valve is opened to enable the required gas to flow through the reaction tank. And setting the temperature of the heating furnace according to the activation requirement to activate the catalyst.
The third step: and after activation, closing a back pressure valve and ball valves 1-5, 1-4, 1-3 and 1-2 in sequence, and preparing gas for catalytic reaction testing. If the pipeline needs to be purged, the three-way valve 4-2 is switched to the gas distribution system to be directly communicated with the evacuation pipeline, the ball valve 1-2, the back pressure valve and the valves 1-5 and 14 are opened, the pipeline is purged for a plurality of times by using reaction gas, and then the subsequent catalytic reaction and the related characterization test are carried out.
The fourth step: and after purging is finished, closing the valve 1-5 and the back pressure valve, closing the ball valve 1-2, and switching the three-way valve 4-2 to communicate the gas distribution system and the reaction tank.
The fifth step: opening ball valves 1-2, 1-3 and 1-4 in sequence, adjusting a back pressure valve to a required pressure, enabling the gas to flow through a reaction tank, setting the temperature of a heating furnace to be required by the experiment, and carrying out catalytic reaction.
And a sixth step: if in-situ electron paramagnetic resonance testing is to be carried out, directly placing a double-layer glass sleeve in a reaction tank into a resonant cavity of an electron paramagnetic resonance spectrometer, and carrying out in-situ testing by utilizing a self-carrying heating device of an instrument; if the quasi-in-situ electron paramagnetic resonance test is to be carried out, the double-layer glass sleeve is placed in a heating furnace for reaction, after the reaction is finished, the ball valves 1-3 and 1-4 are closed, the connecting parts at the upper ends of the ball valves 1-3 and 1-4 are disconnected, and then the double-layer glass sleeve is taken out and placed in a resonant cavity for testing. The back end of the emptying pipe can be connected with a Gas Chromatograph (GC) or an online Mass Spectrometer (MS) to test reaction products.
Claims (9)
1. A heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research is characterized in that: the heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research is composed of a vacuum pump, a cooling device, a connecting pipeline and a reaction tank. The cooling device consists of a liquid nitrogen tank (6) and a cold trap (5), and the upper part of the pipe is provided with an air release valve (2) for balancing the air pressure in the pipe after the vacuum activation is finished; the gas and water adsorbed on the catalyst removed in the vacuum activation process are condensed in the cold trap through the cooling device, so that volatile substances are prevented from entering the vacuum pump to damage the pump body. The connecting pipeline is composed of a ball valve (1), a vacuum gauge (3), a three-way valve (4), a filter (7), a one-way valve (9), a back pressure valve (12), a temperature measuring point (13) and a needle valve (14), and partial pipelines need to be insulated to ensure that gas cannot be condensed in the pipelines. The connecting pipeline connects the gas distribution system, the vacuum pump and the reaction tank, and can be flexibly switched to a catalyst activation or reaction path by using a three-way valve (4). The reaction tank main body is a double-layer glass sleeve (10), and a heating furnace (11) with a quartz window is configured, so that different requirements of the light/heat catalytic reaction characterization of the catalyst under vacuum activation, ventilation activation and quasi-in-situ conditions and the light/heat catalytic reaction characterization under the in-situ conditions can be met.
2. The heterogeneous catalyst activation/reaction device for electron paramagnetic resonance (ESR) studies according to claim 1 has two operation modes when used for catalyst activation: a vacuum activation mode and a vent heating activation mode. The vacuum activation mode is to remove adsorbates on the surface of the catalyst to expose active sites by using high vacuum condition and high temperature as assistance, thereby realizing the activation of the catalyst; the heating and activation of the ventilation body is to connect the gas distribution system with the part of the reaction tank, and to assist the high temperature condition with the target gas, so as to meet the specific gas activation mode requirement needed by some catalysts; meanwhile, the gas distribution system is connected with the reaction tank and can be used as a reaction device required by the catalyst in situ/quasi-in situ characterization, and a double-layer glass sleeve (10) in the reaction tank can be directly placed in a resonant cavity of an electron paramagnetic resonance spectrometer for catalyst characterization; in addition, the evacuation line can be connected to other characterization instruments, such as Gas Chromatography (GC) or online Mass Spectrometry (MS), for in situ characterization of the reaction gas products.
3. The cooling apparatus according to claim 1, wherein: high borosilicate glass is selected as a material of the cold trap (5), two ends of the cold trap are connected with a vacuum pump and a three-way valve (4-1) through a vacuum corrugated pipe, and the right side of the cold trap is connected with a vacuum gauge (3) to observe the internal vacuum degree of the system; the air release valve (2) is used to equalize the system pressure after the vacuum activation operation is finished (the device connection mode needs to be switched to the catalyst reaction path first).
4. The reaction cell of claim 1, wherein: the double-layer glass sleeve (10) used as the reaction tank main body is made of quartz, is convenient for illumination, has an outer diameter less than or equal to 10mm, and can be directly placed in a resonant cavity of an electron paramagnetic resonance spectrometer for catalyst characterization; the wall thickness of the glass sleeve is adjusted according to the internal pressure of an actual system. Two ends of the double-layer glass sleeve (10) are provided with filters (7-1, 7-2) to prevent the catalyst in the tube from blowing out with the air flow to block the pipeline and the valve, and ball valves (1-3, 1-4) are additionally arranged to facilitate the disassembly of the reaction tank and maintain the vacuum or gas environment in the reaction tube. The back end of the gas outlet pipeline is provided with a one-way valve (9) to prevent gas from flowing back and polluting the catalyst. The heating furnace (11) with the quartz window can be made into an independent heating furnace for respectively heating the double-layer glass sleeve (10); the furnace can also be manufactured into an integral hearth, and a plurality of glass sleeves are heated at the same time, and can be designed according to experimental requirements.
5. The connecting line according to claim 1, characterized in that: the three-way valve (4-1) is connected with the cooling device and the reaction tank, and the ball valve (1-2) is assembled at the outlet of the gas distribution system, so that the gas flow generated by the gas distribution system can be controlled to slowly enter the reaction tank in a vacuum state, and the catalyst is prevented from being blown away from a detection area from the bottom of the double-layer glass sleeve by overlarge gas flow when the valve (1-2) is opened. In addition, a three-way valve (4-2) is additionally arranged at the front end of the reaction tank and is directly communicated with an emptying pipeline, so that the gas ratio can be conveniently checked before the reaction starts (through online detection instruments such as an online gas chromatograph and the like). Both ends of a back pressure valve (12) with a temperature measuring point (13) are provided with filters (7-3 and 7-4) so as to prevent solid particles from entering the back pressure valve or a downstream detecting instrument to cause damage to accessories; a ball valve (1-5) and a needle valve (14) which bypass the back pressure valve (12) are used for quickly relieving the pressure of the reaction system.
6. The connecting line according to claim 5, characterized in that: the gas distribution system is connected with the reaction tank, and then the gas paths connected with the emptying pipeline are all heat-insulating pipelines, the temperature is not lower than 130 ℃, on one hand, the condensation of partial low-boiling-point raw material gas or product is prevented, and on the other hand, the preheating of contact catalyst gas is facilitated.
7. The device of claim 1, wherein the parameters are as follows: the vacuum degree of the vacuum pump can reach less than 0.01 mbar; the double-layer glass sleeve (10) in the reaction tank can bear 5MPa of pressure at most, and the sealing joint is made of nonmagnetic materials; the heating furnace (11) adopts programmed heating, and can meet the heating condition from room temperature to 800 ℃.
8. A method of using the catalyst vacuum activation/reaction apparatus of any of claims 1-7, characterized by the steps of:
the first step is as follows: adding a catalyst (8) into the double-layer glass sleeve (10), and if an electron paramagnetic resonance test is required, filling the sample to a height within 4.0 cm; the pipelines are connected in sequence, and the double-layer glass sleeve (10) filled with the catalyst is placed in a heating furnace (11).
The second step is that: the three-way valve (4-1) is switched to the cooling device to be communicated with the reaction tank, and the three-way valve (4-2) is switched to the air inlet pipeline to be communicated with the reaction tank; and (3) closing a ball valve (1-4) at the rear part of the reaction tank, opening a vacuum pump firstly under the condition of ensuring that an air release valve (2) on the cooling device is closed, then opening the ball valve (1-1), slowly opening the ball valve (1-3) for vacuumizing, checking the indication number of a vacuum gauge to ensure that the device system has no air leakage phenomenon and vacuum activation is carried out for a certain time.
The third step: and under the condition that the ball valve (1-2) behind the gas distribution system is closed, switching the three-way ball valve (4-1) to the gas distribution system to be communicated with the reaction tank, opening the air pressure of the balance pipeline of the air release valve (2), closing the vacuum pump, and carrying out the subsequent catalyst reaction process.
The fourth step: under the condition that the three-way valve (4-2) is directly communicated with the gas distribution system and the rear emptying pipe, gas is prepared according to experimental requirements, the ball valve (1-2) is opened, a small amount of gas is used for flushing the pipeline, the ball valve (1-5) and the back pressure valve (12) are closed after flushing is completed, then the ball valve (1-2) is closed, and the three-way valve (4-2) is switched to be communicated with the gas distribution system and the reaction tank.
The fifth step: opening the ball valves (1-2), (1-3) and (1-4) in sequence, adjusting the back pressure valve (12) to the required pressure, enabling the gas to flow through the reaction tank, setting the temperature of the heating furnace (11) to the temperature required by the experiment, and carrying out catalytic reaction.
And a sixth step: if in-situ electron paramagnetic resonance testing is to be carried out, directly placing a double-layer glass sleeve (10) in a reaction tank into a resonant cavity of an electron paramagnetic resonance spectrometer, and carrying out in-situ testing by utilizing a self-carrying heating device of an instrument; if quasi-in-situ electron paramagnetic resonance testing is to be carried out, the double-layer glass sleeve (10) is placed in a heating furnace (11) for reaction, after the reaction is finished, the ball valves (1-3 and 1-4) are closed, the connection of the upper ends of the ball valves (1-3 and 1-4) is disconnected, and then the double-layer glass sleeve (10) is taken out and placed in a resonant cavity for testing. The back end of the emptying pipe can be connected with a Gas Chromatograph (GC) or an online Mass Spectrometer (MS) to test reaction products.
9. A method for using the catalyst gas heating activation/reaction device according to any one of claims 1 to 7, characterized by comprising the steps of:
the first step is as follows: adding a catalyst (8) into the double-layer glass sleeve (10), and if an electron paramagnetic resonance test is required, filling the sample to a height within 4.0 cm; the double-layer glass sleeve (10) filled with the catalyst is placed in a heating furnace (11) according to the connecting pipeline.
The second step is that: the three-way valves (4-1) and (4-2) are communicated with the gas distribution device and the reaction tank, the ball valves (1-3 and 1-4) are opened, the valves (1-5 and 14) are opened, and the back pressure valve (12) is opened, so that the required gas flows through the reaction tank. The temperature of the heating furnace (11) is set according to the activation requirement, and the catalyst is activated.
The third step: after activation, the back pressure valve (12), the ball valves (1-5), (1-4), (1-3) and (1-2) are closed in sequence, and the prepared gas is subjected to a catalytic reaction test. If the gas distribution system needs to change gas, the three-way valve (4-2) is switched to the gas distribution system to be directly communicated with an emptying pipeline, the ball valve (1-2), the back pressure valve (12) and the valves (1-5 and 14) are opened, the pipeline is flushed for a plurality of times by utilizing reaction gas, and then subsequent catalytic reaction and related characterization tests are carried out.
The fourth step: and after the purging is finished, closing the valve (1-5) and the back pressure valve (12), closing the ball valve (1-2), and switching the three-way valve (4-2) to communicate the gas distribution system and the reaction tank.
The fifth step: opening the ball valves (1-2), (1-3) and (1-4) in sequence, adjusting the back pressure valve (12) to the required pressure, enabling the gas to flow through the reaction tank, setting the temperature of the heating furnace (11) as required by the experiment, and carrying out catalytic reaction.
And a sixth step: if in-situ electron paramagnetic resonance testing is to be carried out, directly placing a double-layer glass sleeve (10) in a reaction tank into a resonant cavity of an electron paramagnetic resonance spectrometer, and carrying out in-situ testing by utilizing a self-carrying heating device of an instrument; if quasi-in-situ electron paramagnetic resonance testing is to be carried out, the double-layer glass sleeve (10) is placed in a heating furnace (11) for reaction, after the reaction is finished, the ball valves (1-3 and 1-4) are closed, the connection of the upper ends of the ball valves (1-3 and 1-4) is disconnected, and then the double-layer glass sleeve (10) is taken out and placed in a resonant cavity for testing. The back end of the emptying pipe can be connected with a Gas Chromatograph (GC) or an online Mass Spectrometer (MS) to test reaction products.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111007232.6A CN113702413B (en) | 2021-08-30 | 2021-08-30 | Heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research and use method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111007232.6A CN113702413B (en) | 2021-08-30 | 2021-08-30 | Heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research and use method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113702413A true CN113702413A (en) | 2021-11-26 |
| CN113702413B CN113702413B (en) | 2023-09-29 |
Family
ID=78657055
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111007232.6A Active CN113702413B (en) | 2021-08-30 | 2021-08-30 | Heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research and use method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113702413B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB849929A (en) * | 1956-08-20 | 1960-09-28 | Phillips Petroleum Co | Improved method and apparatus for catalyst activation |
| US6306349B1 (en) * | 1997-03-21 | 2001-10-23 | Korea Institute Of Science And Technology | Catalyst characterization apparatus |
| US20050003552A1 (en) * | 2001-11-20 | 2005-01-06 | Canos Avelino Corma | Test unit for the study of catalysts in short contact time reactions between the catalyst and the reagents |
| CN108760867A (en) * | 2018-03-13 | 2018-11-06 | 上海科技大学 | The combination structure in the reaction in-situ pond and built-in mass spectrum electric quadrupole bar of the interconnection of UHV equipment |
| CN112697832A (en) * | 2020-12-18 | 2021-04-23 | 兰州大学 | In-situ and quasi-in-situ heterogeneous catalysis electron paramagnetic resonance platform and using method |
-
2021
- 2021-08-30 CN CN202111007232.6A patent/CN113702413B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB849929A (en) * | 1956-08-20 | 1960-09-28 | Phillips Petroleum Co | Improved method and apparatus for catalyst activation |
| US6306349B1 (en) * | 1997-03-21 | 2001-10-23 | Korea Institute Of Science And Technology | Catalyst characterization apparatus |
| US20050003552A1 (en) * | 2001-11-20 | 2005-01-06 | Canos Avelino Corma | Test unit for the study of catalysts in short contact time reactions between the catalyst and the reagents |
| CN108760867A (en) * | 2018-03-13 | 2018-11-06 | 上海科技大学 | The combination structure in the reaction in-situ pond and built-in mass spectrum electric quadrupole bar of the interconnection of UHV equipment |
| CN112697832A (en) * | 2020-12-18 | 2021-04-23 | 兰州大学 | In-situ and quasi-in-situ heterogeneous catalysis electron paramagnetic resonance platform and using method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113702413B (en) | 2023-09-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107063784B (en) | Extraction and purification system for dissolving xenon in water and extraction and purification method thereof | |
| CN113145185A (en) | Modular microfluidic nucleic acid detection chip and system | |
| WO2010115192A2 (en) | Multi-chamber rotating valve | |
| CN109772828B (en) | Air bag cleaning device and air bag cleaning method | |
| CN110426480B (en) | Real-time on-line monitoring equipment for water quality volatile organic compounds | |
| CN112697832B (en) | In-situ and quasi-in-situ heterogeneous catalysis electron paramagnetic resonance platform and use method | |
| CN111458151A (en) | Evaporative emission testing equipment for automobile fuel system parts | |
| Wang et al. | Reshaping of pipette tip: A facile and practical strategy for sorbent packing-free solid phase extraction | |
| CN106525999A (en) | Gas chromatographic detection method for gas | |
| CN200996885Y (en) | Helium leak detection mass spectrum auxiliary platform of metal bellows | |
| CN113702413B (en) | Heterogeneous catalyst activation/reaction device for electron paramagnetic resonance research and use method | |
| CN202362215U (en) | Tubular object testing device | |
| JP2008224257A (en) | Catalytic activity evaluation device and evaluation method | |
| CN207908225U (en) | A kind of Trunk Line outer circulation sampler | |
| CN203785981U (en) | Static volumetric method based automatic adsorption measuring device | |
| CN114427939B (en) | Pressure cooker detection equipment and detection method | |
| CN105214562B (en) | Vacuum in situ reaction unit | |
| JP7470624B2 (en) | Gas collecting device and gas collecting method | |
| CN207970657U (en) | A kind of recycling low-concentration organic exhaust gas heating, vacuum desorption apparatus | |
| CN215931217U (en) | Auxiliary leakage detection device | |
| CN111773876A (en) | Precise gas adsorption system for temperature programmed desorption | |
| CN103852397A (en) | Automatic adsorption measuring device by virtue of static volumetric method | |
| CN207086496U (en) | Use for laboratory tank prerinse system | |
| CN206960158U (en) | Take alkene sample storage device of measurement function | |
| CN205826238U (en) | A kind of cavity part high temperature leak detection system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |