Multi-channel catalyst evaluation device and evaluation method for oxygen storage capacity test
The multi-channel catalyst evaluation device enables efficient and accurate testing of catalyst oxygen storage capacity, solving the problems of long testing cycles, high gas consumption, and high costs in traditional devices, and providing an efficient catalyst research and development platform.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YUNNAN PRECIOUS METALS LAB CO LTD
- Filing Date
- 2026-02-06
- Publication Date
- 2026-05-12
AI Technical Summary
Traditional catalyst oxygen storage testing devices suffer from problems such as long testing cycles, high gas consumption, high cost, and unrealistic operating condition simulation, making it difficult to achieve simultaneous comparison and accurate evaluation of multiple reaction conditions.
A multi-channel catalyst evaluation device was designed, including a gas distribution system, a reaction system, and an analysis system. It adopts multiple independent gas distribution channels and parallel single-channel reactors, and is equipped with an OSC gas switching unit, an independent temperature-controlled heating furnace, and a high-speed switching valve to achieve simultaneous testing of multiple atmospheres and precise temperature control. Combined with an automated control system, it evaluates catalyst performance.
It significantly shortens the testing cycle, reduces gas waste, improves testing efficiency and accuracy, can accurately simulate actual working conditions, and supports simultaneous comparison and performance optimization of multiple catalysts.
Smart Images
Figure CN122017116A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of testing technology, specifically relating to a multi-channel catalyst evaluation device and method for oxygen storage capacity testing. Background Technology
[0002] Fixed-bed reactors are core equipment for gas-solid phase catalytic reactions in chemical, petrochemical, energy, and materials fields. Their core principle involves fixing a solid catalyst within a bed, allowing a fluid (gas or liquid) to flow through the bed in a specific direction and react with the solid phase. Due to their high reaction stability and mature technology, they are widely used in various catalytic reaction scenarios. Among them, multi-channel fixed-bed reactors, with their design advantage of being able to conduct multiple reactions in parallel, effectively improve space utilization and experimental efficiency, becoming a research hotspot in fixed-bed reactors in recent years.
[0003] Motor vehicle exhaust contains various harmful substances such as carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (THC), and particulate matter (PM), and direct emissions can cause serious air pollution. With increasing efforts to control environmental pollution, motor vehicle emission regulations have been gradually upgraded, with increasingly stringent requirements from China I to China VI standards. The China VI emission regulations are far more stringent than similar international standards of the same period. Therefore, strictly controlling motor vehicle exhaust pollutant emissions and improving exhaust purification efficiency have become important issues in the current environmental protection field.
[0004] Precious metal catalysts in three-way catalytic converters are core materials for purifying vehicle exhaust gases. They effectively convert pollutants in exhaust gases through catalysis, reducing their pollution levels. The oxygen storage capacity (OSC) of a catalyst is a key indicator of its performance: a higher OSC indicates stronger catalyst activity and better exhaust gas purification; conversely, a lower OSC indicates weaker catalyst activity, making it difficult to meet stringent emission requirements. Therefore, accurate measurement of the catalyst's OSC is crucial for catalyst research, screening, and performance optimization.
[0005] However, the traditional method of testing the oxygen storage capacity of catalysts, which uses a single reactor and a single atmosphere, has significant limitations: on the one hand, a single test can only evaluate one type of catalyst or a set of reaction conditions, resulting in a lengthy testing cycle and severely restricting the catalyst development process; on the other hand, in the single reactor mode, some gases need to be directly vented during gas path switching, resulting in a large waste of gas resources and significantly increasing testing costs; at the same time, traditional devices are difficult to achieve simultaneous comparison of multiple sets of reaction conditions, making it impossible to quickly screen the optimal catalyst raw material formulation and reaction parameters.
[0006] With the rapid development of combinatorial chemistry in the field of catalysis, the synthesis rate of catalysts has increased significantly, placing demands on catalyst performance evaluation technologies for high throughput, high precision, and parallel operation under multiple conditions. While existing multi-channel fixed-bed devices have addressed the issue of parallel testing to some extent, they still have shortcomings in their specific adaptability to oxygen storage capacity testing: some devices lack precise atmosphere switching units, making it difficult to simulate the dynamic changes in air-fuel ratio under real-world conditions, leading to discrepancies between OSC evaluation results and actual performance; some devices have heating systems with insufficient temperature control precision and uneven temperature distribution, affecting the accuracy of oxygen storage capacity test results; and some devices' gas distribution systems cannot achieve precise proportioning and simultaneous supply of liquid feedstocks and multiple gas components.
[0007] Therefore, there is an urgent need to develop a multi-channel catalyst evaluation device for oxygen storage testing that is compact, heats uniformly, has precise and controllable parameters, and can achieve simultaneous testing of multiple atmospheres and periodic switching, in order to solve the problems of long cycle, large gas consumption, high cost, and unrealistic operating condition simulation in traditional testing technologies. Summary of the Invention
[0008] To address the shortcomings of existing technologies, this invention provides a multi-channel catalyst evaluation device for oxygen storage capacity testing that is compact, heats uniformly, has low heat loss, and responds quickly to temperature control. It also provides a multi-channel catalyst evaluation method for oxygen storage capacity testing.
[0009] The multi-channel catalyst evaluation device for oxygen storage capacity testing of the present invention is implemented as follows: it includes a gas distribution system, a reaction system, multiple analysis systems, and a control system. The reaction system consists of multiple single-channel reactors arranged in parallel. The multiple analysis systems correspond to the multiple single-channel reactors of the reaction system, and are used to detect the concentration values and air-fuel ratio changes of each test component before and after the reaction in real time. The gas distribution system includes a carrier gas pipeline, a base atmosphere gas pipeline, multiple liquid feedstock inlet pipelines, and an OSC gas switching unit. The carrier gas pipeline and the base atmosphere gas pipeline each include a gas source I, a pressure regulating valve, a pressure gauge, a switching valve, and a check valve connected in sequence. The outlet end of the check valve corresponding to the carrier gas pipeline and the base atmosphere gas pipeline is divided into multiple branches I. A mass flow controller is installed on each branch I. The end of any branch I of the base atmosphere gas pipeline is merged with the end of the corresponding branch I of the carrier gas pipeline and then connected to the inlet end of the corresponding single-channel reactor. The liquid raw material inlet pipeline includes a liquid supply source, an auxiliary carrier gas source, and a liquid evaporator. The liquid supply source and the auxiliary carrier gas source are respectively connected to the inlet end of the liquid evaporator. Mass flow controllers are respectively installed on the pipelines connecting the liquid supply source and the auxiliary carrier gas source to the inlet end of the liquid evaporator. The outlet end of the liquid evaporator is connected to the inlet end of the corresponding single-channel reactor through a pipeline. The OSC gas switching unit includes a gas source II, a CO gas pipeline, and an O2 gas pipeline. Both the CO gas pipeline and the O2 gas pipeline include a gas source II, a pressure regulating valve, a pressure gauge, a switching valve, and a check valve connected in sequence. The outlet of the check valve corresponding to the CO gas pipeline and the O2 gas pipeline is divided into multiple branches II that output CO and O2 at different concentrations. Each branch II is equipped with a mass flow controller and a high-speed switching valve and is connected to the inlet of each single-channel reactor. Each branch II of the CO gas pipeline and the O2 gas pipeline is equipped with an auxiliary carrier gas. The auxiliary carrier gas pipeline is equipped with a mass flow controller and its outlet is connected to the pipeline before the inlet of the high-speed switching valve of the corresponding branch II. The control system is electrically connected to each of the switching valves, mass flow controllers, high-speed switching valves, analysis systems, and reaction systems of the gas distribution system.
[0010] Furthermore, the gas source I of the basic atmosphere gas pipeline includes at least one of carbon dioxide, nitric oxide, ammonia, methane, hydrogen, propylene, and propane, and the liquid source includes volatile liquids such as water, benzene, hydrocarbons, or alcohols.
[0011] Furthermore, the outlet ends of the one-way valves corresponding to the CO gas pipeline and the O2 gas pipeline are each divided into three branches II. The three branches II of the CO gas pipeline are CO-high gas branch, CO-medium gas branch, and CO-low gas branch, used to output three different concentrations of CO; the three branches II of the O2 gas pipeline are O2-high gas branch, O2-medium gas branch, and O2-low gas branch, used to output three different concentrations of O2; each of the three branches II of the CO gas pipeline and the O2 gas pipeline is connected to the inlet end of each single-channel reactor of the reaction system.
[0012] Furthermore, the CO-high gas branch and the O2-high gas branch form gas path A, the CO-low gas branch and the O2-low gas branch form gas path C, and the CO-medium gas branch and the O2-medium gas branch form gas path B. Gas path A mixes with other gas components in the gas distribution system to form an oxygen-rich atmosphere, gas path C mixes with other gas components in the gas distribution system to form an oxygen-deficient atmosphere, and gas path B mixes with other gas components in the gas distribution system to form a stoichiometric atmosphere. The control system controls the corresponding high-speed switching valves to circulate gas path A, gas path B, and gas path C into the corresponding single-channel reactor in a predetermined alternation cycle, or to circulate gas path A and gas path C into the corresponding single-channel reactor in a predetermined alternation cycle.
[0013] Furthermore, the reaction system includes three identical single-channel reactors and three independently temperature-controlled heating furnaces corresponding to the single-channel reactors. Each single-channel reactor includes an upper heating zone and a lower reaction zone. The heating zone of the single-channel reactor is located in the corresponding heating furnace. The reaction zone of the single-channel reactor is equipped with a sample tube filled with a catalyst. Each gas component output from the gas distribution system is introduced into the reaction zone of the single-channel reactor. The heating furnace is electrically connected to the control system.
[0014] Furthermore, a gas mixer is provided at the top of the reaction zone of the single-channel reactor, and multiple gas inlet pipes are provided inside the single-channel reactor that penetrate the heating zone and extend to the gas mixer at their bottom ends. Each gas component output by the gas distribution system is connected to the corresponding gas inlet pipe in the single-channel reactor. The reaction system also includes a thermocouple detector that passes through the single-channel reactor and is located at the front end of the catalyst. The thermocouple detector is electrically connected to the analysis system.
[0015] Furthermore, the analysis system includes a sampling tube, a gas analyzer, a pre-oxygen sensor, and a post-oxygen sensor. The sampling tube is divided into a front-end sampling tube and a rear-end sampling tube. The front-end sampling tube is equipped with a first control valve, and the rear-end sampling tube is equipped with a second control valve. The front-end sampling tube and the pre-oxygen sensor are located at the front end of the sample tube of the single-channel reactor, and the rear-end sampling tube and the post-oxygen sensor are located at the rear end of the sample tube of the single-channel reactor. The front-end and rear-end sampling tubes, the pre-oxygen sensor, and the post-oxygen sensor of each single-channel reactor are electrically connected to the gas analyzer. The first control valve, the second control valve, and the gas analyzer are electrically connected to the control system.
[0016] The multi-channel catalyst evaluation method for oxygen storage capacity testing of the present invention is implemented as follows: Based on the aforementioned multi-channel catalyst evaluation device for oxygen storage capacity testing, it includes catalyst installation, atmosphere replacement, data acquisition before reaction, data acquisition after reaction, reaction atmosphere control, reaction temperature control, and purging steps. The specific contents of each step are as follows: A. Catalyst installation: Place sample tubes containing the same volume of catalyst into the reaction zone of each single-channel reactor; B. Atmosphere replacement: The control system opens the corresponding switching valves of the gas distribution system to introduce the carrier gas, base atmosphere, liquid raw material and auxiliary carrier gas of the gas distribution system into each single-channel reactor. At the same time, at least the A-channel gas and B-channel gas of the OSC gas switching unit are introduced into two single-channel reactors respectively, or the A-channel gas, B-channel gas and C-channel gas of the OSC gas switching unit are introduced into three single-channel reactors respectively. C. Data collection before reaction: The control system controls the gas analyzer to start data collection and opens the first control valve of the analysis system. Through the front-end tube and the front oxygen sensor, the gas analyzer records the concentration value I and the air-fuel ratio I of each gas component in the single-channel reactor before reaction. D. Data collection after reaction: The control system closes the first control valve of the analysis system and simultaneously opens the second control valve. The gas analyzer records the concentration value II of each gas component and the air-fuel ratio II after the reaction in the single-channel reactor. E. Reaction Atmosphere Control: In step D, the control system controls the opening and closing parameters of each high-speed switching valve in the OSC gas switching unit, so that gas A and gas B are circulated into two single-channel reactors in a predetermined alternating cycle, or gas A, gas B and gas C are circulated into three single-channel reactors in a predetermined alternating cycle. F. Reaction Temperature Control: In step D, the control system controls the heating furnace to heat each single-channel reactor to the required reaction temperature at a specific heating rate according to the pre-set heating program and maintains it for a period of time. The gas analyzer records the reaction temperature detected by the thermocouple detector. G. Purging: The control system shuts down the mass flow controllers, switching valves, and high-speed switching valves on each pipeline of the gas distribution system, stops the heating of the furnace, and retains the carrier gas to purge each pipeline, single-channel reactor, and gas analyzer for a predetermined time. After the purge is completed, the OSC test of multiple catalysts is performed.
[0017] Furthermore, both the carrier gas and the auxiliary carrier gas are nitrogen, the base atmosphere includes carbon dioxide, nitric oxide, propylene, and propane, and the liquid raw material is liquid water.
[0018] Furthermore, the single-channel reactor and sample tube are high-temperature resistant quartz tubes with a design temperature of ±1000℃; the high-speed switching valve includes a pneumatic valve and a solenoid valve for controlling the pneumatic valve, the solenoid valve is electrically connected to the control system, and the response time of the high-speed switching valve is ≤100ms.
[0019] The present invention has the following beneficial effects: 1. This invention adopts a combined design of a reaction system consisting of multiple independent gas distribution systems and multiple parallel single-channel reactors, which can simultaneously conduct parallel tests of oxygen storage capacity (OSC) of multiple identical or different catalysts. Compared with the traditional single-reactor test mode, it eliminates the need to repeatedly build the experimental environment, greatly shortens the test cycle of multiple catalysts, and thus significantly improves the test efficiency. It also avoids the waste of gas source caused by the partial gas exhaust during gas path circulation switching, and reduces the test cost.
[0020] 2. This invention constructs three typical atmospheres—oxygen-rich, oxygen-deficient, and stoichiometric—through an OSC gas switching unit. Combined with a high-speed switching valve with a response time ≤100ms, it can achieve cyclic switching of multiple atmospheres according to a predetermined cycle. This allows for precise simulation of the dynamic changes in the exhaust air-fuel ratio during actual vehicle operation, making the performance evaluation of the catalyst OSC more closely resemble real-world conditions and increasing the reference value of the evaluation results.
[0021] 3. In the gas distribution system of this invention, each pipeline is equipped with a mass flow controller. Combined with components such as pressure regulating valves and pressure gauges, it can achieve precise proportioning and flow control of carrier gas, base atmosphere, liquid raw materials and OSC gas components. Moreover, each single-channel reactor adopts an independently temperature-controlled heating furnace, and is equipped with a thermocouple detector that runs through the single-channel reactor. It can quickly respond to temperature adjustment needs, thereby ensuring uniform and stable temperature in each reactor, effectively reducing the impact of temperature fluctuations on test results, and ultimately achieving precise and controllable test parameters.
[0022] 4. Each single-channel reactor of the present invention corresponds to an independent analysis system. Through the coordinated action of the front-end sampling tube, the back-end sampling tube, and the front and rear oxygen sensors, key data such as the concentration of each gas component and the air-fuel ratio before and after the reaction can be collected in real time. By synchronously recording the aforementioned multi-dimensional data and combining the comparative analysis of parallel tests, the analysis system reduces the random errors of a single test, thereby improving the accuracy of catalyst OSC performance evaluation.
[0023] 5. The basic atmosphere of this invention is compatible with various gases such as carbon dioxide, nitric oxide, and propylene, and the liquid feedstock supports various media such as water, methanol, and ethanol, thus adapting to the OSC testing requirements of different types of three-way catalysts. At the same time, the device can flexibly switch test modes, supporting both simultaneous comparative testing of multiple catalysts and performance studies of a single catalyst under different operating conditions by adjusting parameters such as atmosphere type, cycle period, and reaction temperature, providing diversified data support for catalyst development and formulation optimization.
[0024] 6. The single-channel reactor and sample tube of this invention are made of high-temperature resistant quartz tube material, which has both good thermal stability and chemical inertness, and the overall structure is compact with little heat loss. The design of the gas mixer and multiple gas inlet pipelines can not only ensure that the components of the gas are uniformly mixed in the reaction zone, but also reduce the shortcomings of direct heating of the mixed gas which is prone to side reactions. It can also avoid local overheating or overcooling that may be caused by mixing hot and cold gases, as well as side reactions and catalyst deactivation caused by temperature fluctuations, further ensuring the consistency of test conditions, while facilitating the installation, maintenance and sample replacement of the equipment.
[0025] In summary, this invention, through a multi-channel parallel architecture, a precise gas distribution system, high-speed atmosphere switching, independent and precise temperature control, and full-process automated control, successfully solves the key technical bottlenecks in traditional catalyst oxygen storage capacity testing, such as "long cycle, high gas consumption, high cost, and simulation distortion." It not only significantly improves testing efficiency and data accuracy but also provides an efficient and reliable experimental platform for the research and development, formulation screening, and performance optimization of novel three-way catalysts. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the multi-channel catalyst evaluation device for oxygen storage capacity testing according to the present invention. Figure 2 This is a schematic diagram of the single-channel reactor air inlet structure of the present invention; Figure 3 This is a schematic diagram of the OSC gas switching unit structure of the present invention; In the diagram, 1-Gas distribution system, 11-Carrier gas pipeline, 12-Base atmosphere gas pipeline, 13-Liquid raw material inlet pipeline, 14-OSC gas switching unit, 15-Pressure regulator, 16-Pressure gauge, 17-Switch valve, 18-Check valve, 19-Mass flow controller, 1A-Liquid supply source, 1B-Auxiliary carrier gas source, 1C-Liquid evaporator, 1D-CO gas pipeline, 1E-O2 gas pipeline, 1F-High-speed switching valve, 1G-Auxiliary carrier gas, 2-Reaction system, 21-Single-channel reactor, 22-Heating furnace, 23-Gas mixer, 24-Gas inlet pipeline, 25-Catalyst, 26-Sample tube, 27-Thermocouple detector, 3-Analysis system, 31-Gas analyzer, 32-Pre-oxygen sensor, 33-Post-oxygen sensor, 34-Front-end sampling tube, 35-Rear-end sampling tube, 4-Control system, AA gas path, BB gas path, CC gas path. Detailed Implementation
[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this does not limit the present invention in any way. Any changes or improvements made based on the teachings of the present invention shall fall within the protection scope of the present invention.
[0028] like Figure 1 , 2 As shown in Figure 3, the multi-channel catalyst evaluation device for oxygen storage capacity testing of the present invention includes a gas distribution system 1, a reaction system 2, multiple analysis systems 3, and a control system 4. The reaction system 2 is composed of multiple single-channel reactors 21 arranged in parallel. The multiple analysis systems 3 correspond to the multiple single-channel reactors 21 of the reaction system 2, and are used to detect the concentration values and air-fuel ratio changes of each test component before and after the reaction in real time. The gas distribution system 1 includes a carrier gas pipeline 11, a base atmosphere gas pipeline 12, multiple liquid feedstock inlet pipelines 13, and an OSC gas switching unit 14. The carrier gas pipeline 11 and the base atmosphere gas pipeline 12 each include a gas source I, a pressure regulating valve 15, a pressure gauge 16, a switching valve 17, and a check valve 18 connected in sequence. The outlet end of the check valve 18 corresponding to the carrier gas pipeline 11 and the base atmosphere gas pipeline 12 is divided into multiple branches I. A mass flow controller (MFC) 19 is installed on each branch I. The end of any branch I of the base atmosphere gas pipeline 12 is merged with the end of the branch I corresponding to the carrier gas pipeline 11 and then connected to the inlet end of the corresponding single-channel reactor 21. The liquid raw material inlet pipeline 13 includes a liquid supply source 1A, an auxiliary carrier gas source 1B, and a liquid evaporator 1C. The liquid supply source 1A and the auxiliary carrier gas source 1B are respectively connected to the inlet end of the liquid evaporator 1C. Mass flow controllers 19 are respectively installed on the pipelines connecting the liquid supply source 1A and the auxiliary carrier gas source 1B to the inlet end of the liquid evaporator 1C. The outlet end of the liquid evaporator 1C is connected to the inlet end of the corresponding single-channel reactor 21 through a pipeline. The OSC gas switching unit 14 includes a gas source II, a CO gas pipeline 1D, and an O2 gas pipeline 1E. Both the CO gas pipeline 1D and the O2 gas pipeline 1E include a gas source II, a pressure regulating valve 15, a pressure gauge 16, a switching valve 17, and a check valve 18 connected in sequence. The outlet of the check valve 18 corresponding to the CO gas pipeline 1D and the O2 gas pipeline 1E is divided into multiple branches II that output CO and O2 of different concentrations. Each branch II is equipped with a mass flow controller 19 and a high-speed switching valve 1F and is connected to the inlet of each single-channel reactor 21. Each branch II of the CO gas pipeline 1D and the O2 gas pipeline 1E is equipped with an auxiliary carrier gas 1G. The auxiliary carrier gas 1G is equipped with a mass flow controller 19 and its outlet is connected to the pipeline before the inlet of the high-speed switching valve 1F of the corresponding branch II. The control system 4 is electrically connected to each of the switching valves 17, mass flow controllers 19, high-speed switching valves 1F, analysis systems 3, and reaction systems 2 of the gas distribution system 1.
[0029] It should be noted that the liquid raw material in the liquid raw material inlet pipeline 13 is self-supplying liquid source 1A and enters the liquid evaporator 1C for vaporization after the flow rate and velocity are precisely controlled by the mass flow controller 19. The liquid raw material is then carried out in the form of steam in the liquid evaporator 1C by the auxiliary carrier gas 1G in the auxiliary carrier gas source 1B through the corresponding mass flow controller 19. The outlet end of the liquid evaporator 1C is connected to the inlet end of the corresponding single-channel reactor 21 through a pipeline.
[0030] The auxiliary carrier gas 1G can precisely control the gas flow rate on each branch II and avoid excessively high local concentrations.
[0031] The gas source I of the basic atmosphere gas pipeline 12 supplies at least one of carbon dioxide, nitric oxide, ammonia, methane, hydrogen, propylene, and propane, and the liquid source 1A supplies volatile liquids including water, benzene, hydrocarbons, or alcohols.
[0032] The outlet of the one-way valve 18 corresponding to the CO gas pipeline 1D and the O2 gas pipeline 1E is divided into three branches II. The three branches II of the CO gas pipeline 1D are CO-high gas branch, CO-medium gas branch, and CO-low gas branch, which are used to output three different concentrations of CO. The three branches II of the O2 gas pipeline 1E are O2-high gas branch, O2-medium gas branch, and O2-low gas branch, which are used to output three different concentrations of O2. Each of the three branches II of the CO gas pipeline 1D and the O2 gas pipeline 1E is connected to the inlet of each single-channel reactor 21 of the reaction system 2.
[0033] The CO-high gas branch and the O2-high gas branch form gas path A, the CO-low gas branch and the O2-low gas branch form gas path C, and the CO-medium gas branch and the O2-medium gas branch form gas path B. Gas path A mixes with other gas components in the gas distribution system 1 to form an oxygen-rich atmosphere, gas path C mixes with other gas components in the gas distribution system 1 to form an oxygen-deficient atmosphere, and gas path B mixes with other gas components in the gas distribution system 1 to form a stoichiometric atmosphere. The control system 4 controls the corresponding high-speed switching valve 1F to circulate gas path A, gas path B and gas path C into the corresponding single-channel reactor 21 according to a predetermined alternation cycle, or to circulate gas path A and gas path C into the corresponding single-channel reactor 21 according to a predetermined alternation cycle.
[0034] The reaction system 2 includes three identical single-channel reactors 21 and three independently temperature-controlled heating furnaces 22 corresponding to the single-channel reactors 21. Each single-channel reactor 21 includes an upper heating zone and a lower reaction zone. The heating zone of the single-channel reactor 21 is located in the corresponding heating furnace 22. The reaction zone of the single-channel reactor 21 is equipped with a sample tube 26 filled with a catalyst 25. The gas components output by the gas distribution system 1 are introduced into the reaction zone of the single-channel reactor 21. The heating furnace 22 is electrically connected to the control system 4.
[0035] The heating furnace 22 is an infrared heating furnace.
[0036] A gas mixer 23 is provided at the upper part of the reaction zone of the single-channel reactor 21. Multiple gas inlet pipes 24 are provided in the single-channel reactor 21, which penetrate the heating zone and extend to the gas mixer 23 at their bottom ends. Each gas component output by the gas distribution system 1 is connected to the corresponding gas inlet pipe 24 in the single-channel reactor 21. The reaction system 2 also includes a thermocouple detector 27 that passes through the single-channel reactor 21 and is provided at the front end of the catalyst 25. The thermocouple detector 27 is electrically connected to the analysis system 3.
[0037] The analysis system 3 includes a sampling tube, a gas analyzer 31, a front oxygen sensor 32, and a rear oxygen sensor 33. The sampling tube is divided into a front sampling tube 34 and a rear sampling tube 35. The front sampling tube 34 is equipped with a first control valve, and the rear sampling tube 35 is equipped with a second control valve. The front sampling tube 34 and the front oxygen sensor 32 are located at the front end of the sample tube 26 of the single-channel reactor 21, and the rear sampling tube 35 and the rear oxygen sensor 33 are located at the rear end of the sample tube 26 of the single-channel reactor 21. The front sampling tube 34, the rear sampling tube 35, the front oxygen sensor 32, and the rear oxygen sensor 33 of each single-channel reactor 21 are electrically connected to the gas analyzer 31. The first control valve, the second control valve, and the gas analyzer 31 are electrically connected to the control system 4.
[0038] The control system 4 includes a PLC controller and a human-machine interface connected to it, used to set test parameters, operation control parameters, and monitor the test status and collect test data in real time.
[0039] It should be noted that the pressure regulating valve 15, pressure gauge 16, switching valve 17, check valve 18, mass flow controller 19, high-speed switching valve 1F, auxiliary carrier gas 1G, gas analyzer 31, front oxygen sensor 32, rear oxygen sensor 33, front sampling tube 34, rear sampling tube 35 and their supporting devices, etc., can draw on existing technical means and will not be described in detail here.
[0040] This invention provides a multi-channel catalyst evaluation method for oxygen storage capacity testing. Based on the aforementioned multi-channel catalyst evaluation device for oxygen storage capacity testing, the method includes catalyst installation, atmosphere replacement, data acquisition before reaction, data acquisition after reaction, reaction atmosphere control, reaction temperature control, and purging steps. The specific details of each step are as follows: A. Catalyst installation: Place sample tubes 26 containing the same volume of catalyst 25 in the reaction zone of each single-channel reactor 21; B. Atmosphere replacement: The control system 4 opens the corresponding switch valves 17 of the gas distribution system 1, and introduces the carrier gas, base atmosphere, liquid raw material and auxiliary carrier gas 1G of the gas distribution system 1 into each single-channel reactor 21 respectively. At the same time, at least the A-channel gas and B-channel gas of the OSC gas switching unit 14 are introduced into two single-channel reactors 21 respectively, or the A-channel gas, B-channel gas and C-channel gas of the OSC gas switching unit 14 are introduced into three single-channel reactors 21 respectively. C. Data collection before reaction: The control system 4 controls the gas analyzer 31 to start data collection and opens the first control valve of the analysis system 3. Through the front-end tube 34 and the front oxygen sensor 32, the gas analyzer 31 records the concentration value I and air-fuel ratio I of each gas component in the single-channel reactor 21 before reaction. D. Collect post-reaction data: Control system 4 closes the first control valve of analysis system 3 and simultaneously opens the second control valve. Gas analyzer 31 records the concentration value II and air-fuel ratio II of each gas component after reaction in single-channel reactor 21. E. Reaction Atmosphere Control: In step D, the control system 4 controls the opening and closing parameters of each high-speed switching valve 1F in the OSC gas switching unit 14, so that gas A and gas B are circulated into two single-channel reactors 21 in a predetermined alternating cycle, or gas A, gas B and gas C are circulated into three single-channel reactors 21 in a predetermined alternating cycle. F. Reaction temperature control: In step D, the control system 4 controls the heating furnace 22 to heat each single-channel reactor 21 to the required reaction temperature at a specific heating rate according to the preset heating program and maintain it for a period of time. The gas analyzer 31 records the reaction temperature detected by the thermocouple detector 27. G. Purging: The control system 4 shuts down the mass flow controller 19, switch valve 17 and high-speed switching valve 1F on each pipeline of the gas distribution system 1, and stops the heating of the furnace 22. The carrier gas is used to purge each pipeline, single-channel reactor 21 and gas analyzer 31 for a predetermined time. After the purge is completed, the OSC test of multiple catalysts 25 is performed.
[0041] Both the carrier gas and the auxiliary carrier gas 1G are nitrogen, the base atmosphere includes carbon dioxide, nitric oxide, propylene, and propane, and the liquid raw material is liquid water.
[0042] The single-channel reactor 21 and sample tube 26 are high-temperature resistant quartz tubes with a design temperature of ±1000℃; the high-speed switching valve 1F includes a pneumatic valve and a solenoid valve for controlling the pneumatic valve. The solenoid valve is electrically connected to the control system 4, and the response time of the high-speed switching valve 1F is ≤100ms.
[0043] Example 1
[0044] The multi-channel catalyst evaluation device of this invention for oxygen storage capacity testing was used to perform two-channel OSC testing on the catalyst.
[0045] S100: Place sample tubes 26 containing the same volume of catalyst 25 in the reaction zones of the two single-channel reactors 21 respectively.
[0046] S200: Control system 4 activates the corresponding switching valves 17 of gas distribution system 1, respectively introducing the carrier gas, base atmosphere, liquid feedstock, and auxiliary carrier gas 1G from gas distribution system 1 into two single-channel reactors 21. Simultaneously, the A-channel gas from OSC gas switching unit 14 is introduced into one single-channel reactor 21, and the C-channel gas is introduced into the other single-channel reactor 21. The aforementioned carrier gas and auxiliary carrier gas 1G are both nitrogen, the base atmosphere is CO2, NO, C3H6, and C3H8, and the liquid feedstock is liquid water.
[0047] S300: The control system 4 controls the gas analyzers 31 corresponding to the two single-channel reactors 21 to start the data acquisition function according to the preset program, and opens the first control valves corresponding to the two analysis systems 3 respectively. Through the front-end pipe 34 and the front oxygen sensor 32, the two gas analyzers 31 record the concentration value I and air-fuel ratio I of each gas component in the corresponding single-channel reactor 21 before the reaction.
[0048] S400: According to the preset program, the control system 4 closes the first control valve of each analysis system 3 and opens the corresponding second control valve. The two gas analyzers 31 record the concentration value II and air-fuel ratio II of each gas component after reaction in the corresponding single-channel reactor 21.
[0049] S500: In step S400, the control system 4 controls the opening and closing parameters of each high-speed switching valve 1F in the OSC gas switching unit 14 according to the preset program, so that the gas from path A and path B are circulated into the two single-channel reactors 21 in a predetermined alternation cycle; wherein, the switching cycle of the high-speed switching valve 1F is 30S.
[0050] S600: In step S400, the control system 4 controls the heating furnace 22 to heat the two single-channel reactors 21 to the required reaction temperature at a specific heating rate and maintain it for a period of time according to the preset heating program. The gas analyzer 31 records the reaction temperature detected by the thermocouple detector 27.
[0051] S700: Control system 4 shuts down the mass flow controller 19, switch valve 17 and high-speed switching valve 1F on each pipeline of gas distribution system 1, and stops the heating of furnace 22, while retaining the carrier gas to purge each pipeline, single-channel reactor 21 and gas analyzer 31 for a predetermined time. After the purge is completed, the OSC test of the two catalysts 25 is completed.
[0052] Example 2
[0053] The multi-channel catalyst evaluation device of this invention for oxygen storage capacity testing was used to perform three-channel OSC testing on the catalyst.
[0054] S100: Place sample tubes 26 containing the same volume of catalyst 25 in the reaction zones of the three single-channel reactors 21 respectively.
[0055] S200: Control system 4 opens the corresponding switching valves 17 of gas distribution system 1, respectively introducing the carrier gas, base atmosphere, liquid feedstock, and auxiliary carrier gas 1G from gas distribution system 1 into the three single-channel reactors 21. Simultaneously, the A-channel gas, B-channel gas, and C-channel gas from OSC gas switching unit 14 are respectively introduced into the three single-channel reactors 21. The aforementioned carrier gas and auxiliary carrier gas 1G are both nitrogen, the base atmosphere is CO2, NO, C3H6, and C3H8, and the liquid feedstock is liquid water.
[0056] S300: The control system 4 controls the gas analyzers 31 corresponding to the three single-channel reactors 21 to start the data acquisition function according to the preset program, and opens the first control valves corresponding to the three analysis systems 3 respectively. Through the front-end pipe 34 and the front oxygen sensor 32, the three gas analyzers 31 record the concentration value I and air-fuel ratio I of each gas component in the corresponding single-channel reactor 21 before the reaction.
[0057] S400: According to the preset program, the control system 4 closes the first control valve of each analysis system 3 and opens the corresponding second control valve. The three gas analyzers 31 record the concentration value II and air-fuel ratio II of each gas component after reaction in the corresponding single-channel reactor 21.
[0058] S500: In step S400, the control system 4 controls the opening and closing parameters of each high-speed switching valve 1F in the OSC gas switching unit 14 according to the preset program, so that the gas from path A, path B and path C are cyclically introduced into the three single-channel reactors 21 respectively in a predetermined alternation cycle; wherein, the switching cycle of the high-speed switching valve 1F is 30S.
[0059] S600: In step S400, the control system 4 controls the heating furnace 22 to heat the three single-channel reactors 21 to the required reaction temperature at a specific heating rate and maintain it for a period of time according to the preset heating program. The gas analyzer 31 records the reaction temperature detected by the thermocouple detector 27.
[0060] S700: Control system 4 shuts down the mass flow controller 19, switch valve 17 and high-speed switching valve 1F on each pipeline of gas distribution system 1, and stops the heating of furnace 22, while retaining the carrier gas to purge each pipeline, single-channel reactor 21 and gas analyzer 31 for a predetermined time. After the purge is completed, the OSC test of the three catalysts 25 is completed.
[0061] By following the steps in Examples 1 and 2 above, the change in air-fuel ratio before and after the reaction within a predetermined time period can be collected, and the oxygen storage capacity of each catalyst can be calculated by using the time difference of the oxygen sensor signals before and after the reaction and the air-fuel ratio amplitude.
[0062] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A multi-channel catalyst evaluation device for oxygen storage capacity testing, characterized in that: It includes a gas distribution system (1), a reaction system (2), multiple analysis systems (3), and a control system (4). The reaction system (2) consists of multiple single-channel reactors (21) arranged in parallel. The multiple analysis systems (3) correspond to the multiple single-channel reactors (21) of the reaction system (2) respectively, and are used to detect the concentration values and air-fuel ratio changes of each test component before and after the reaction in real time. The gas distribution system (1) includes a carrier gas pipeline (11), a base atmosphere gas pipeline (12), multiple liquid raw material inlet pipelines (13), and an OSC gas switching unit (14). The carrier gas pipeline (11) and the basic atmosphere gas pipeline (12) each include a gas source I, a pressure regulator (15), a pressure gauge (16), a switch valve (17), and a check valve (18) connected in sequence. The outlet end of the check valve (18) corresponding to the carrier gas pipeline (11) and the basic atmosphere gas pipeline (12) is divided into multiple branches I. A mass flow controller (19) is installed on each branch I. The end of any branch I of the basic atmosphere gas pipeline (12) is merged with the end of the branch I corresponding to the carrier gas pipeline (11) and then connected to the inlet end of the corresponding single-channel reactor (21). The liquid raw material inlet pipeline (13) includes a liquid supply source (1A), an auxiliary carrier gas source (1B), and a liquid evaporator (1C). The liquid supply source (1A) and the auxiliary carrier gas source (1B) are respectively connected to the inlet end of the liquid evaporator (1C). Mass flow controllers (19) are respectively installed on the pipelines connecting the liquid supply source (1A) and the auxiliary carrier gas source (1B) to the inlet end of the liquid evaporator (1C). The outlet end of the liquid evaporator (1C) is connected to the inlet end of the corresponding single-channel reactor (21) through a pipeline. The OSC gas switching unit (14) includes a gas source II, a CO gas pipeline (1D), and an O2 gas pipeline (1E). The CO gas pipeline (1D) and the O2 gas pipeline (1E) each include a gas source II, a pressure regulating valve (15), a pressure gauge (16), a switching valve (17), and a check valve (18) connected in sequence. The outlet of the check valve (18) corresponding to the CO gas pipeline (1D) and the O2 gas pipeline (1E) is divided into multiple branches II that output CO and O2 of different concentrations. Each branch II is equipped with a mass flow controller (19) and a high-speed switching valve (1F) and is connected to the inlet of each single-channel reactor (21). Each branch II of the CO gas pipeline (1D) and the O2 gas pipeline (1E) is equipped with an auxiliary carrier gas (1G). The auxiliary carrier gas (1G) is equipped with a mass flow controller (19) and its outlet is connected to the pipeline before the inlet of the high-speed switching valve (1F) of the corresponding branch II. The control system (4) is electrically connected to each of the switching valves (17), mass flow controllers (19), high-speed switching valves (1F), analysis systems (3), and reaction systems (2) of the gas distribution system (1).
2. The multi-channel catalyst evaluation device for oxygen storage capacity testing according to claim 1, characterized in that: The gas source I of the basic atmosphere gas pipeline (12) includes at least one of carbon dioxide, nitric oxide, ammonia, methane, hydrogen, propylene and propane, and the liquid source (1A) includes volatile liquids such as water, benzene, hydrocarbons or alcohols.
3. The multi-channel catalyst evaluation device for oxygen storage capacity testing according to claim 1 or 2, characterized in that: The outlet of the one-way valve (18) corresponding to the CO gas pipeline (1D) and the O2 gas pipeline (1E) is divided into three branches II. The three branches II of the CO gas pipeline (1D) are CO-high gas branch, CO-medium gas branch, and CO-low gas branch, which are used to output three different concentrations of CO. The three branches II of the O2 gas pipeline (1E) are O2-high gas branch, O2-medium gas branch, and O2-low gas branch, which are used to output three different concentrations of O2. The three branches II of the CO gas pipeline (1D) and the O2 gas pipeline (1E) are respectively connected to the inlet of each single-channel reactor (21) of the reaction system (2).
4. The multi-channel catalyst evaluation device for oxygen storage capacity testing according to claim 3, characterized in that: The CO-high gas branch and the O2-high gas branch form gas path A, the CO-low gas branch and the O2-low gas branch form gas path C, the CO-medium gas branch and the O2-medium gas branch form gas path B. Gas path A mixes with other gas components in the gas distribution system (1) to form an oxygen-rich atmosphere, gas path C mixes with other gas components in the gas distribution system (1) to form an oxygen-deficient atmosphere, and gas path B mixes with other gas components in the gas distribution system (1) to form a stoichiometric atmosphere. The control system (4) controls the corresponding high-speed switching valve (1F) to circulate gas path A, gas path B and gas path C into the corresponding single-channel reactor (21) according to a predetermined alternation cycle, or to circulate gas path A and gas path C into the corresponding single-channel reactor (21) according to a predetermined alternation cycle.
5. The multi-channel catalyst evaluation device for oxygen storage capacity testing according to claim 4, characterized in that: The reaction system (2) includes three single-channel reactors (21) with the same structure and three independently temperature-controlled heating furnaces (22) corresponding to the single-channel reactors (21). The single-channel reactor (21) includes an upper heating zone and a lower reaction zone. The heating zone of the single-channel reactor (21) is set in the corresponding heating furnace (22). The reaction zone of the single-channel reactor (21) is equipped with a sample tube (26) filled with catalyst (25). The gas components output by the gas distribution system (1) are introduced into the reaction zone of the single-channel reactor (21). The heating furnace (22) is electrically connected to the control system (4).
6. The multi-channel catalyst evaluation device for oxygen storage capacity testing according to claim 5, characterized in that: A gas mixer (23) is provided at the top of the reaction zone of the single-channel reactor (21). Multiple gas inlet pipes (24) are provided in the single-channel reactor (21) that penetrate the heating zone and extend to the bottom of the gas mixer (23). Each gas component output by the gas distribution system (1) is connected to the corresponding gas inlet pipe (24) in the single-channel reactor (21). The reaction system (2) also includes a thermocouple detector (27) that passes through the single-channel reactor (21) and is located at the front end of the catalyst (25). The thermocouple detector (27) is electrically connected to the analysis system (3).
7. The multi-channel catalyst evaluation device for oxygen storage capacity testing according to claim 5, characterized in that: The analysis system (3) includes a sampling tube, a gas analyzer (31), a front oxygen sensor (32), and a rear oxygen sensor (33). The sampling tube is divided into a front sampling tube (34) and a rear sampling tube (35). The front sampling tube (34) is equipped with a first control valve, and the rear sampling tube (35) is equipped with a second control valve. The front sampling tube (34) and the front oxygen sensor (32) are located at the front end of the sample tube (26) of the single-channel reactor (21), and the rear sampling tube (35) and the rear oxygen sensor (33) are located at the rear end of the sample tube (26) of the single-channel reactor (21). The front sampling tube (34) and the rear sampling tube (35), the front oxygen sensor (32), and the rear oxygen sensor (33) of each single-channel reactor (21) are electrically connected to the gas analyzer (31). The first control valve, the second control valve, and the gas analyzer (31) are electrically connected to the control system (4).
8. A multi-channel catalyst evaluation method for oxygen storage capacity testing, characterized in that: The multi-channel catalyst evaluation device for oxygen storage capacity testing as described in claim 7 includes catalyst installation, atmosphere replacement, data acquisition before reaction, data acquisition after reaction, reaction atmosphere control, reaction temperature control, and purging steps. The specific details of each step are as follows: A. Catalyst installation: Place sample tubes (26) containing the same volume of catalyst (25) in the reaction zone of each single-channel reactor (21); B. Atmosphere replacement: The control system (4) opens the corresponding switch valves (17) of the gas distribution system (1) and introduces the carrier gas, base atmosphere, liquid raw material and auxiliary carrier gas (1G) of the gas distribution system (1) into each single-channel reactor (21). At the same time, at least the A-path gas and B-path gas of the OSC gas switching unit (14) are introduced into two single-channel reactors (21), or the A-path gas, B-path gas and C-path gas of the OSC gas switching unit (14) are introduced into three single-channel reactors (21). C. Data collection before reaction: The control system (4) controls the gas analyzer (31) to start data collection and open the first control valve of the analysis system (3). Through the front-end pipe (34) and the front oxygen sensor (32), the gas analyzer (31) records the concentration value I and air-fuel ratio I of each gas component in the single-channel reactor (21) before reaction. D. Collect data after reaction: The control system (4) closes the first control valve of the analysis system (3) and opens the second control valve at the same time. The gas analyzer (31) records the concentration value II and air-fuel ratio II of each gas component after reaction in the single-channel reactor (21). E. Reaction Atmosphere Control: In step D, the control system (4) controls the opening and closing parameters of each high-speed switching valve (1F) in the OSC gas switching unit (14) so that the A-path gas and the B-path gas are circulated into the two single-channel reactors (21) in a predetermined alternating cycle, or the A-path gas, the B-path gas and the C-path gas are circulated into the three single-channel reactors (21) in a predetermined alternating cycle. F. Reaction temperature control: In step D, the control system (4) controls the heating furnace (22) to heat each single-channel reactor (21) to the required reaction temperature at a specific heating rate according to the pre-set heating program and maintain it for a period of time. The gas analyzer (31) records the reaction temperature detected by the thermocouple detector (27). G. Purging: The control system (4) shuts down the mass flow controller (19), switch valve (17) and high-speed switching valve (1F) on each pipeline of the gas distribution system (1), and stops the heating of the heating furnace (22), while retaining the carrier gas to purge each pipeline, single-channel reactor (21) and gas analyzer (31) for a predetermined time. After the purge is completed, the OSC test of multiple catalysts (25) is completed.
9. The multi-channel catalyst evaluation method for oxygen storage capacity testing according to claim 8, characterized in that: Both the carrier gas and the auxiliary carrier gas (1G) are nitrogen, the base atmosphere includes carbon dioxide, nitric oxide, propylene, and propane, and the liquid feedstock is liquid water.
10. The multi-channel catalyst evaluation method for oxygen storage capacity testing according to claim 8, characterized in that: The single-channel reactor (21) and sample tube (26) are high-temperature resistant quartz tubes with a design temperature of ±1000℃; the high-speed switching valve (1F) includes a pneumatic valve and a solenoid valve for controlling the pneumatic valve. The solenoid valve is electrically connected to the control system (4). The response time of the high-speed switching valve (1F) is ≤100ms.