CN105067752B - Program heating analysis equipment and method for testing property of its catalyst - Google Patents

Abstract

The invention provides a temperature-programmed analysis device and a method for testing the properties of its catalyst, which can be used for tests such as temperature-programmed reduction, temperature-programmed oxidation, and temperature-programmed desorption. The equipment includes a first gas supply pipeline, a second gas supply pipeline, a pressure reducing valve, a pressure stabilizing valve, a constant flow valve, a pressure gauge, a mass flow meter, a one-way valve, a six-way valve, a U-shaped reaction tube, and a heating furnace , thermocouple, temperature controller, thermal conductivity cell detector, data processing workstation and computer. By introducing the design of the six-way valve, the present invention can conveniently realize the switching of two channels of gas, so as to achieve the purpose of simultaneously performing the pretreatment process of the catalyst sample and the baseline step of the instrument, which greatly saves time and improves the test efficiency; By introducing the design of the plug-in heating furnace, it is equipped with 3 plug-in heating furnaces, which facilitates the replacement of high-temperature heating furnaces, saves the waiting time for the heating furnace to cool down, and improves the test efficiency.

Description

Temperature-programmed analysis equipment and its catalyst property test method

technical field

The invention belongs to the technical field of gas-solid phase catalysis, and in particular relates to a temperature-programmed analysis device and a method for testing properties of catalysts thereof, which are mainly used for testing the oxidation-reduction performance and surface acidity and alkalinity of catalyst samples.

Background technique

As we all know, more than 80% of the chemical industry involves catalytic processes, and the level of development of catalytic technology reflects the degree of development of a country. At the same time, catalytic technology also plays a pivotal role in the fields of environmental pollution control, new energy development and new material development. According to the similarities and differences of physical states, catalytic reactions can be divided into: homogeneous catalysis and heterogeneous catalysis. Among them, heterogeneous catalysis has become a research hotspot due to its advantages such as simple separation and reusable catalyst. Gas-solid phase catalysis is a typical heterogeneous catalysis, which plays a very important role in the field of environment and energy, especially in today's environment with increasing environmental pollution and energy shortage, its importance is becoming more and more obvious.

The oxidation-reduction performance and surface acidity and alkalinity of catalyst samples can significantly affect their catalytic performance in gas-solid phase catalytic reactions, and thus become important regulatory indicators for researchers to optimize existing catalysts and create new catalysts. How to obtain the redox performance and surface acidity and alkalinity data of catalyst samples simply and efficiently has aroused great interest of catalysis workers. Expose the catalyst sample to specific gas conditions, perform temperature programming and record the corresponding data, and then analyze the data, which can effectively obtain information such as the oxidation-reduction performance and surface acidity and alkalinity of the catalyst sample. Therefore, instrument developers have been working on the research and development of related instruments and equipment.

At present, although some companies at home and abroad have developed temperature-programmed analysis equipment for testing the oxidation-reduction performance and surface acidity and alkalinity of catalyst samples. But there is a common problem - the test efficiency is too low: the pretreatment (purging) of the catalyst sample and the baseline of the instrument cannot be carried out simultaneously; each catalyst sample needs to be re-baselined before testing; Slow, which greatly reduces the efficiency of scientific researchers.

Contents of the invention

In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a simple and efficient temperature-programmed analysis device and a method for testing properties of the catalyst that can be used for oxidation-reduction performance and surface acidity and alkalinity tests of catalyst samples, The pretreatment (purging) process of the catalyst sample and the baseline step of the instrument can be carried out at the same time, saving time and improving test efficiency.

In order to achieve the above and other related purposes, the present invention provides a temperature-programmed analysis equipment for temperature-programmed reduction, temperature-programmed oxidation and temperature-programmed desorption tests, including a first gas supply line, a second gas supply line, and a reactor , a heating device, a thermal conductivity cell detector and a six-way valve, the first gas supply line is connected to the first interface of the six-way valve, and the second gas supply line passes through the first side gas path of the thermal conductivity cell detector and is connected to the The third port of the six-way valve is connected, and the fourth port of the six-way valve is connected to the second side gas path of the thermal conductivity cell detector through the pipeline and then emptied; the reactor is installed in the heating device, and the air inlet of the reactor and the gas outlet are respectively connected to the second port and the fifth port of the six-way valve through pipelines, and the sixth port of the six-way valve is emptied.

As a preference: both the first gas supply pipeline and the second gas supply pipeline include a gas cylinder, a pressure reducing valve, a pressure stabilizing valve, a constant flow valve, a pressure gauge, a mass flow meter and a one-way valve arranged sequentially on the gas pipeline. Valve, the one-way valve of the first gas supply line is connected to the first interface of the six-way valve, and the one-way valve of the second gas supply line is connected to the first side gas path of the thermal conductivity cell detector.

Preferably: a data processing workstation and a computer are also included, and the data processing workstation is respectively connected with the thermal conductivity cell detector and the computer for data processing and transmission.

Preferably: it also includes a temperature detection element and a temperature controller, the temperature detection element is inserted into the catalyst bed in the reactor, and is connected with the temperature controller, and the temperature controller is connected with the heating device.

As a preference: the temperature detecting element is a thermocouple or a temperature sensor.

As a preference: the reactor is a U-shaped reaction tube, and the heating device is a plug-in heating furnace, including one working heating furnace and at least one standby heating furnace.

As a preference: the first purge gas is high-purity N ₂ , the first reaction gas is H ₂ /N ₂ or CO/He mixed gas, and the second reaction gas is O ₂ /N ₂ mixed gas, The second purge gas is high-purity He, and the third reaction gas is NH ₃ /He mixed gas, CO ₂ /He mixed gas, SO ₂ /He mixed gas, NO/He mixed gas or O ₂ /He mixed gas mixed gas.

The present invention also provides a method for testing the properties of catalysts, including temperature-programmed reduction test, temperature-programmed oxidation test, and temperature-programmed desorption test, as well as the temperature-programmed analysis equipment;

The temperature-programmed reduction test is as follows: the first purge gas passes through the first gas supply pipeline to purge the catalyst sample at a set temperature; after cooling down to room temperature, switch the six-way valve to empty the first gas supply pipeline through the sixth interface , the first reaction gas flows through the catalyst bed through the second gas supply pipeline, and the temperature is programmed to increase the reduction reaction between the first reaction gas and the catalyst sample; then use the thermal conductivity cell detector to detect the first reaction gas signal; collected by the data processing workstation The thermal conductivity cell detector data is finally displayed visually through the computer.

The temperature-programmed oxidation test is as follows: after the reduction reaction of the above-mentioned temperature-programmed reduction test is completed and lowered to room temperature, the first reaction gas is switched to the second reaction gas, and the temperature is programmed to cause the second reaction gas to react with the reduced catalyst sample. Oxidation reaction; then detect the second reaction gas signal with a thermal conductivity cell detector; collect the data of the thermal conductivity cell detector by the data processing workstation, and finally display it visually through the computer.

The temperature-programmed desorption test is as follows: the second purge gas passes through the second gas supply pipeline to purge the catalyst sample at a set temperature; after the temperature drops to 100°C, switch the six-way valve, and the third reaction gas passes through the first gas supply pipeline The catalyst sample is adsorbed and saturated; the six-way valve is switched again, and the second purge gas is passed through the second gas supply pipeline to purge the physical adsorbate of the catalyst sample, and then passes through the second side of the thermal conductivity cell detector. The air path is emptied; the temperature is programmed to desorb the chemically adsorbed species on the surface of the catalyst sample, and the signal of the desorbed species is detected by the thermal conductivity cell detector; the data of the thermal conductivity cell detector is collected by the data processing workstation, and finally displayed visually by the computer.

As a preference: in the temperature-programmed reduction test, the pretreatment process of the catalyst sample and the baseline of the instrument can be carried out simultaneously: when the first purge gas passes through the first gas supply pipeline to purge the catalyst sample, the first reaction gas can flow through The gas path on the first side of the thermal conductivity cell detector enters the second side gas path of the thermal conductivity cell detector through the six-way valve, so that the thermal conductivity cell detector can work normally and the instrument can go to the baseline normally.

As a preference: the first purge gas is high-purity N ₂ , the first reaction gas is H ₂ /N ₂ or CO/He mixed gas, and the second reaction gas is O ₂ /N ₂ mixed gas, The second purge gas is high-purity He, and the third reaction gas is NH ₃ /He mixed gas, CO ₂ /He mixed gas, SO ₂ /He mixed gas, NO/He mixed gas or O ₂ /He mixed gas mixed gas.

The working principle of the present invention is as follows:

The temperature-programmed analysis equipment can be used for temperature-programmed reduction, temperature-programmed oxidation, and temperature-programmed desorption tests. For temperature-programmed reduction, the principle is: high-purity N ₂ is purged through the first gas supply pipeline at a specific temperature to clean the surface of the catalyst sample; after cooling down to room temperature, H ₂ /N ₂ (or CO/He) The mixed gas flows through the catalyst bed through the second gas supply pipeline; the temperature is programmed to reduce the _H2 or CO and the catalyst sample, and the _H2 or CO signal is detected by the thermal conductivity cell detector; the thermal conductivity cell is collected by the data processing workstation The detector data is finally displayed visually through the computer. For temperature-programmed oxidation, the principle is: high _- purity N ₂ is purged through the first gas supply pipeline at a specific temperature to clean the surface of the catalyst sample _{; The} gas pipeline _flows through the catalyst bed _; the temperature is programmed to reduce the _{H 2} and the catalyst sample _; The reduced catalyst sample undergoes an oxidation reaction, and the O ₂ signal is detected by a thermal conductivity cell detector; the data of the thermal conductivity cell detector is collected by a data processing workstation, and finally displayed visually by a computer. For temperature-programmed desorption, the principle is: high _- purity He is purged through the _second gas supply pipeline at a specific temperature to clean the surface of the catalyst sample; or SO ₂ /He or NO/He or O ₂ /He) mixed gas flows through the catalyst bed through the first gas supply pipeline to saturate the catalyst sample adsorption, at this temperature blow off the residual gas of physical adsorption with high-purity He, the procedure The temperature is raised to desorb the chemically adsorbed species on the surface of the catalyst sample, and the signal of the desorbed species is detected by the thermal conductivity cell detector; the data of the thermal conductivity cell detector is collected by the data processing workstation, and finally displayed visually by the computer. It should be noted that high-purity _N2 and high-purity He are in the range of purity that can be determined in the prior art.

As mentioned above, the beneficial effects of the present invention are:

1. By introducing the design of the six-way valve, it is convenient to realize the switching of the two channels of gas, so as to achieve the purpose of the pretreatment (purging) process of the catalyst sample and the baseline step of the instrument at the same time, which greatly saves time and improves improved testing efficiency;

2. By introducing the design of the plug-in heating furnace, it is equipped with multiple plug-in heating furnaces, which facilitates the replacement of high-temperature heating furnaces, saves the waiting time for the heating furnace to cool down, and improves the test efficiency;

3. The required materials are universal and easy to obtain; the operation is simple and convenient, and there is no special requirement for testers; the energy consumption is low and the efficiency is high; it has a significant application prospect.

Description of drawings

Fig. 1 is the working principle diagram of the temperature programming analysis equipment involved in the present invention;

Fig. 2 is the temperature-programmed reduction test comparison diagram of the temperature-programmed analysis equipment involved in the present invention and similar products of other companies;

Fig. 3 is the temperature-programmed oxidation test comparison diagram of the temperature-programmed analysis equipment involved in the present invention and similar products of other companies;

Fig. 4 is a graph comparing the temperature-programmed desorption test of the temperature-programmed analysis equipment involved in the present invention and similar products of other companies.

Part number description

1, 2: gas cylinder; 3: pressure reducing valve; 4: pressure stabilizing valve; 5: constant flow valve; 6: pressure gauge; 7: mass flow meter; 8: one-way valve; 9: six-way valve; 10: U-shaped reaction tube; 11: heating furnace; 12: thermocouple; 13: sample; 14: temperature controller; 15: thermal conductivity cell detector; 16: data processing workstation; 17: computer.

detailed description

The implementation of the present invention will be illustrated by specific specific examples below, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

As shown in Figure 1, a temperature-programmed analysis equipment is used for temperature-programmed reduction, temperature-programmed oxidation, and temperature-programmed desorption tests, including a first gas supply line, a second gas supply line, a six-way valve 9, and a U-shaped reaction Tube 10, heating device, thermal conductivity cell detector 15, data processing workstation 16 and computer 17, the six-way valve 9 in the figure is the first interface, the second interface, the third interface, the fourth interface, The fifth interface and the sixth interface; the first gas supply pipeline is connected to the first interface of the six-way valve 9, the second gas supply pipeline is connected to the first side gas circuit of the thermal conductivity cell detector 15 through the pipeline, and the first side gas The road is connected to the third interface of the six-way valve 9 through the pipeline, and the fourth interface of the six-way valve 9 is connected to the second side gas path of the thermal conductivity cell detector 15 through the pipeline, and the second side gas path is emptied; U-shaped reaction The tube 10 is installed in the heating device. The air inlet of the U-shaped reaction tube 10 is connected to the second interface of the six-way valve 9 through a pipeline, and the gas outlet of the U-shaped reaction tube 10 is connected to the fifth interface through a pipeline. The sixth port of valve 9 is emptied. Both the first gas supply pipeline and the second gas supply pipeline include gas cylinders 1 and 2, pressure reducing valve 3, pressure stabilizing valve 4, constant flow valve 5, pressure gauge 6, mass flow Meter 7 and one-way valve 8, the one-way valve 8 of the first gas supply pipeline is connected with the first interface of the six-way valve 9, the one-way valve 8 of the second gas supply pipeline is connected with the first side of the thermal conductivity cell detector 15 Gas connection.

The data processing workstation 16 is respectively connected with the thermal conductivity cell detector 15 and the computer 17 for data processing and transmission. In order to facilitate the control of the reaction temperature in the U-shaped reaction tube 10, a temperature detection element and a temperature controller 14 are also provided. The temperature detection element is inserted into the catalyst bed in the reactor and connected with the temperature controller 14. The temperature controller 14 is connected to the heating device connection.

In this example, the temperature detecting element is a thermocouple 12 . In order to improve the test efficiency and reduce the waiting time for the heating furnace 11 to cool down, the heating device is a plug-in heating furnace 11, which includes a working heating furnace and 2 standby heating furnaces for easy switching.

The direction of the arrow shown in Figure 1 is the gas flow direction. In this example, the gas cylinder 1 in the first gas supply pipeline is gas A, and the gas cylinder 2 in the second gas supply pipeline is gas B. Gas A is exported from gas cylinder 1. After that, the pressure is controlled by the pressure reducing valve 3, and then flows through the pressure stabilizing valve 4 and the constant flow valve 5 to ensure the pressure and air flow of the gas A are stable, and then an external pressure gauge 6 is connected to detect the actual pressure, and then the mass flow meter 7 is used to accurately control The flow of gas A is connected in series with a one-way valve 8 to prevent other gases from recoiling and damaging the mass flow meter 7, and finally a six-way valve 9 is used to control the flow of gas A, as shown in Figure 1, through the dotted line ( The first port to the second port) enters the U-shaped reaction tube 10 to contact the catalyst sample 13; it is directly emptied through the solid-line pipeline (the first port to the sixth port). After the gas B is exported from the gas cylinder 2, the pressure is controlled by the pressure reducing valve 3, and then flows through the pressure stabilizing valve 4 and the constant flow valve 5 to ensure that the pressure and flow of the gas B are stable, and then an external pressure gauge 6 is connected to detect the actual pressure. A mass flowmeter 7 is used to precisely control the flow of gas B, and a check valve 8 is connected in series to prevent the recoil of other gases from damaging the mass flowmeter 7. Finally, gas B flows through the first side gas path of the thermal conductivity cell detector 15 and then passes through Six-way valve 9 controls the flow of gas B, as shown in Figure 1, directly enters the second side gas path of thermal conductivity cell detector 15 through the dotted line pipeline (the third interface to the fourth interface) and then empties; The solid-line pipeline (from the third interface to the second interface) enters the U-shaped reaction tube 10 to contact the catalyst sample 13 , and then flows through the second-side gas path of the thermal conductivity cell detector 15 to be emptied. The temperature programming process is mainly controlled by a temperature controller 14 , a thermocouple 12 and a heating furnace 11 . The thermocouple 12 detects the temperature of the catalyst bed and feeds it back to the temperature controller 14, and the temperature controller 14 sends a signal to control the heating furnace 11 to raise the temperature according to the set temperature rise program, so as to realize the purpose of the programmed temperature rise. After the gas signal in the temperature program heating process is detected by the thermal conductivity cell detector 15, the corresponding data is collected by the data processing workstation 16, and finally displayed visually by the computer 17.

In the equipment involved in the present invention, when gas A pretreats (purging) the catalyst sample 13, gas B can flow through the first side gas path of the thermal conductivity cell detector 15 and then enter through the dotted line pipeline of the six-way valve 9 The second-side air path of the thermal conductivity cell detector 15 is used to ensure that the thermal conductivity cell detector 15 can work normally and the instrument can go to the baseline normally. That is to say, the pretreatment (purging) process of the catalyst sample 13 and the baseline step of the instrument can be carried out at the same time, avoiding the disadvantages of these two steps of similar products of other companies that must be carried out separately, which greatly saves time and improves the test performance. efficiency. In addition, the equipment involved in the present invention is equipped with three plug-in heating furnaces. After each heating step is completed, the heating furnace in a high temperature state can be removed and replaced with a heating furnace at room temperature for subsequent heating. The process effectively avoids the shortcoming of slow cooling of fixed heating furnaces of similar products of other companies, which greatly saves the waiting time for heating furnace cooling and improves test efficiency.

The present invention also provides a catalyst property testing method based on the above-mentioned temperature-programmed analysis equipment, including temperature-programmed reduction test, temperature-programmed oxidation test and temperature-programmed desorption test methods.

The temperature-programmed reduction test is as follows: the first purge gas passes through the first gas supply pipeline to purge the catalyst sample 13 at a set temperature; after cooling down to room temperature, switch the six-way valve 9 so that the first gas supply pipeline passes through the sixth interface Evacuate, the first reaction gas flows through the catalyst bed through the second gas supply pipeline, and the temperature is programmed to raise the first reaction gas and the catalyst sample 13 to undergo a reduction reaction; then use the thermal conductivity cell detector 15 to detect the signal of the first reaction gas; The data processing workstation 16 collects the data of the thermal conductivity cell detector 15 , and finally displays it visually through the computer 17 .

The temperature-programmed oxidation test is as follows: after the reduction reaction of the above-mentioned temperature-programmed reduction test is completed and lowered to room temperature, the first reaction gas is switched to the second reaction gas, and the temperature is programmed to make the second reaction gas and the reduced catalyst sample 13 An oxidation reaction occurs; then the second reaction gas signal is detected by the thermal conductivity cell detector 15;

The temperature-programmed desorption test is as follows: the second purge gas passes through the second gas supply pipeline to purge the catalyst sample 13 at a set temperature; The gas supply pipeline is connected to make the catalyst sample 13 adsorbed and saturated; the six-way valve 9 is switched again, and the second purge gas is passed through the second gas supply pipeline again to purge the physical adsorbate of the catalyst sample 13, and then detected by the thermal conductivity cell. The gas path on the second side of the device 15 is emptied; the temperature is programmed to desorb the chemically adsorbed species on the surface of the catalyst sample 13, and the signal of the desorbed species is detected by the thermal conductivity cell detector 15; the thermal conductivity cell detector 15 is collected by the data processing workstation 16 The data is visually displayed by the computer 17 at last.

The temperature-programmed reduction test, temperature-programmed oxidation test and temperature-programmed desorption test methods provided in this example are compared with existing technical means through specific examples, and the test results and effects are equivalent; specific examples are as follows:

1. Programmed temperature reduction test

Accurately weigh 10-1000mg of catalyst sample 13 and fill it into U-shaped reaction tube 10, insert thermocouple 12 into the catalyst bed, and install heating furnace 11; high-purity _N2 is exported from the gas cylinder 1 of the first gas supply pipeline The pressure reducing valve 3 controls the pressure within the range of 0.1-0.5MPa, and the mass flow meter 7 accurately controls the flow rate to be 10-200ml/min; by switching the six-way valve 9, the high-purity N ₂ is controlled to flow through the catalyst bed pair along the dotted line pipeline. The catalyst sample 13 is pretreated (purged) to clean the surface of the catalyst sample 13, and the pretreatment (purged) condition is 100-500° C. for 0.5-1 h. At the same time, after the 3%-10% H ₂ /N ₂ (or CO/He) mixed gas is exported from the gas cylinder 2 of the second gas supply line, the pressure is controlled by the pressure reducing valve 3 within the range of 0.1-0.5 MPa, and the The mass flow meter 7 accurately controls the flow rate to be 10-100ml/min; after passing through the first side gas path of the thermal conductivity cell detector 15, it passes through the six-way valve 9 and directly enters the second side of the thermal conductivity cell detector 15 along the dotted line pipeline Evacuate the air circuit; set the temperature of the thermal conductivity cell detector 15 at 60-120°C, control the bridge current within the range of 50-100mA, and start collecting data to take the baseline. After the pretreatment (purging) of the catalyst sample 13 is completed, the baseline has already been flattened, and the heating furnace 11 in a high temperature state is removed and replaced with a heating furnace 11 at room temperature; the six-way valve 9 is switched so that the high _- purity N 3%-10% H ₂ /N ₂ (or CO/He) mixed gas flows through the catalyst bed along the solid line, during the temperature program (heating rate 5-20°C/min) A reduction reaction occurs with the catalyst sample 13, the _H2 (or CO) signal is detected by the thermal conductivity cell detector 15, and finally the data is recorded by the data processing workstation 16 and displayed and saved on the computer 17. The temperature-programmed reduction test under the same conditions was carried out on similar products of other companies, and the comparison results are shown in Figure 2 (taking 7% H ₂ /N ₂ mixture gas for temperature-programmed reduction of CeO ₂ as an example). The test results show that the two test effects are equivalent.

2. Programmed temperature rise oxidation test

The temperature-programmed oxidation test is based on the above-mentioned temperature-programmed reduction, taking off the heating furnace 11 in a high-temperature state and replacing it with a heating furnace 11 at room temperature; switching the gas in the second gas supply line to 2%-25% O ₂ /N ₂ mixed gas, the pressure is controlled by the pressure reducing valve 3 in the range of 0.1-0.5MPa, and the flow rate is accurately controlled by the mass flow meter 7 to be 10-100ml/min; the first side gas flowing through the thermal conductivity cell detector 15 After the road, through the six-way valve 9 and flow through the catalyst bed along the solid line pipeline, ventilate at room temperature for 0.5-1h to discharge the residual reducing gas. The reduced catalyst sample 13 undergoes an oxidation reaction, the O ₂ signal is detected by the thermal conductivity cell detector 15 , and finally the data is recorded by the data processing workstation 16 and displayed and saved on the computer 17 . The temperature-programmed oxidation test under the same conditions was carried out on similar products of other companies, and the comparison results are shown in Figure 3 (taking the reduced CuO/SiO ₂ in the temperature-programmed oxidation of 20% O ₂ /N ₂ mixed gas as an example). The test results show that the two test effects are equivalent.

3. Programmed temperature desorption test

Accurately weigh 50-1000 mg of catalyst sample 13 and fill it into U-shaped reaction tube 10, insert thermocouple 12 into the catalyst bed, and install heating furnace 11; The pressure valve 3 controls the pressure within the range of 0.1-0.5MPa, and the mass flow meter 7 accurately controls the flow rate to be 10-200ml/min; after flowing through the first side gas path of the thermal conductivity cell detector 15, it passes through the six-way valve 9 along the real The line pipeline enters the catalyst bed to pretreat (purge) the catalyst sample 13 to clean the surface of the catalyst sample 13, and the pretreatment (purge) condition is to purge at 100-500°C for 0.5-1h. After cooling down to 100°C, 0.01%-2% NH ₃ /He (or CO ₂ /He or SO ₂ /He or NO/He or O ₂ /He) mixed gas is exported from the gas cylinder 1 of the first gas supply pipeline The pressure is controlled by the pressure reducing valve 3 within the range of 0.1-0.5MPa, and the flow rate is accurately controlled by the mass flow meter 7 to be 10-100ml/min; by switching the six-way valve 9, the 0.01%-2%NH ₃ /He (or CO ₂ /He or SO ₂ /He or NO/He or O ₂ /He) mixed gas flows through the catalyst bed along the dotted pipeline to make catalyst sample 13 adsorb at 100°C for 0.5-2h until saturated. Then, switch the six-way valve 9 so that 10-100ml/min high-purity He flows through the first side gas path of the thermal conductivity cell detector 15 and enters the catalyst bed through the six-way valve 9 along the solid line pipeline at 100°C The catalyst sample 13 was purged for 0.5-1 h to remove physically adsorbed NH ₃ (or CO ₂ or SO ₂ or NO or O ₂ ), and then evacuated through the gas path on the second side of the thermal conductivity cell detector 15 . At the same time, set the temperature of the thermal conductivity cell detector 15 at 60-120°C, control the bridge current within the range of 50-100mA, and start collecting data to take the baseline. After the physical adsorption gas purging of the catalyst sample 13 is completed (the baseline has already leveled out), the temperature program is started from 100°C. For desorption, the signal of the desorbed species is detected by the thermal conductivity cell detector 15, and finally the data is recorded by the data processing workstation 16 and displayed and saved on the computer 17. The temperature-programmed desorption test under the same conditions was carried out on similar products of other companies, and the comparison results are shown in Figure 4 (purging the CeO absorbed and saturated by ₁ % NH ₃ /He mixed gas with high-purity He made the temperature-programmed desorption occur. attached as an example). The test results show that the two test effects are equivalent.

The present invention can conveniently realize the switching of the two-way gas, so as to achieve the purpose of simultaneously carrying out the pretreatment (purging) process of the catalyst sample and the baseline step of the instrument, which greatly saves time and improves the test efficiency; it is equipped with 3 plug-in The pull-out heating furnace facilitates the replacement of the high-temperature heating furnace, saves the waiting time for the heating furnace to cool down, improves the test efficiency, and the test results are accurate.

Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention should still be covered by the claims of the present invention.

Claims (9)

1. A method for testing properties of a catalyst, comprising a temperature-programmed reduction test, a temperature-programmed oxidation test and a temperature-programmed desorption test, characterized in that: a temperature-programmed analysis device is used to test, which includes a first gas supply pipeline, a second gas supply line Gas pipeline, reactor, heating device, thermal conductivity cell detector and six-way valve, the first gas supply pipeline is connected with the first interface of the six-way valve, and the second gas supply pipeline passes through the first port of the thermal conductivity cell detector. The side gas path is connected to the third port of the six-way valve, and the fourth port of the six-way valve is connected to the second side gas path of the thermal conductivity cell detector through the pipeline and then emptied; the reactor is installed in the heating device, and the reaction The air inlet and the air outlet of the device are respectively connected to the second interface and the fifth interface of the six-way valve through pipelines, and the sixth interface of the six-way valve is emptied; The temperature-programmed reduction test is as follows: the first purge gas passes through the first gas supply pipeline to purge the catalyst sample at a set temperature; after cooling down to room temperature, switch the six-way valve to empty the first gas supply pipeline through the sixth interface , the first reaction gas flows through the catalyst bed through the second gas supply pipeline, and the temperature is programmed to raise the first reaction gas and the catalyst sample to undergo a reduction reaction; then use a thermal conductivity cell detector to detect the signal of the first reaction gas; The temperature-programmed oxidation test is as follows: after the reduction reaction of the above-mentioned temperature-programmed reduction test is completed and lowered to room temperature, the first reaction gas is switched to the second reaction gas, and the temperature is programmed to cause the second reaction gas to react with the reduced catalyst sample. an oxidation reaction; then detect a second reaction gas signal with a thermal conductivity cell detector; The temperature-programmed desorption test is as follows: the second purge gas passes through the second gas supply pipeline to purge the catalyst sample at a set temperature; after the temperature drops to 100°C, switch the six-way valve, and the third reaction gas passes through the first gas supply pipeline The catalyst sample is adsorbed and saturated; the six-way valve is switched again, and the second purge gas is passed through the second gas supply pipeline to purge the physical adsorbate of the catalyst sample, and then passes through the second side of the thermal conductivity cell detector. The gas path is emptied; the temperature is programmed to desorb the chemically adsorbed species on the surface of the catalyst sample, and the signal of the desorbed species is detected by a thermal conductivity cell detector; The above-mentioned thermal conductivity cell detector signal data is collected and output by the data processing workstation. 2. The property testing method of the catalyst according to claim 1, characterized in that: in the temperature programmed reduction test, the pretreatment process of the catalyst sample and the baseline of the instrument can be carried out simultaneously: the first purge gas passes through the first When the gas supply pipeline is purging the catalyst sample, the first reaction gas can flow through the first side gas path of the thermal conductivity cell detector and then enter the second side gas path of the thermal conductivity cell detector through the six-way valve, so that the thermal conductivity cell detection The instrument works normally, and the instrument can take the baseline normally. 3. The catalyst property testing method according to claim 1, characterized in that: the first purge gas is high-purity _N2 , and the first reaction gas is _H2 / _N2 or CO/He mixed gas , the second reaction gas is O ₂ /N ₂ mixed gas, the second purge gas is high-purity He, and the third reaction gas is NH ₃ /He mixed gas, CO ₂ /He mixed gas, SO ₂ /He mixed gas, NO/He mixed gas or O ₂ /He mixed gas. 4. The property testing method of the catalyst according to claim 1, characterized in that: the first gas supply pipeline and the second gas supply pipeline all include a gas cylinder, a pressure reducing valve, a stabilizer, and Pressure valve, constant flow valve, pressure gauge, mass flow meter and one-way valve, the one-way valve of the first gas supply pipeline is connected with the first interface of the six-way valve, the one-way valve of the second gas supply pipeline It is connected to the first side air path of the thermal conductivity cell detector. 5. The property testing method of the catalyst according to claim 1, characterized in that: the programmed temperature analysis equipment also includes a data processing workstation and a computer, and the data processing workstation is connected with a thermal conductivity cell detector and a computer respectively to carry out Data processing and delivery. 6. the property test method of catalyst according to claim 1, it is characterized in that: described temperature programming analysis equipment also comprises temperature detection element and temperature controller, and described temperature detection element inserts the catalyst bed layer in the reactor, and It is connected with a temperature controller, and the temperature controller is connected with a heating device. 7. The method for testing the properties of catalysts according to claim 6, characterized in that: the temperature detecting element is a thermocouple. 8. The property testing method of catalyst according to claim 1, characterized in that: the reactor is a U-shaped reaction tube, and the heating device is a plug-in heating furnace, including a working heating furnace and at least one standby heating furnace. furnace. 9. The catalyst property testing method according to claim 1, characterized in that: the gas fed into the first gas supply pipeline is high-purity N ₂ , 0.01%-2% NH ₃ /He mixed gas, 0.01 %-2% CO ₂ /He mixed gas, 0.01%-2% SO ₂ /He mixed gas, 0.01%-2% NO/He mixed gas or 0.01%-2% O ₂ /He mixed gas; second gas supply pipe The gas fed into the pipeline is 3%-10% H ₂ /N ₂ mixed gas, 3%-10% CO/He mixed gas, 2%-25% O ₂ /N ₂ mixed gas or high-purity He.