Device and method for electrically-assisted catalytic oxidation of carbon monoxide

Abstract

The invention relates to a device and a method for electrically-assisted catalytic oxidation of carbon monoxide, and relates to the technical field of air pollution control. Comprising a shell, a reactor, an electric driving unit, a voltage and current control assembly and a temperature control unit, the reactor, the electric driving unit and the temperature control unit are arranged in the shell; an air inlet pipe and an air outlet pipe are arranged at two ends of the shell, are provided with air draft / blowing devices, and are connected with an air inlet and an air outlet of the reactor; the electric driving unit is electrically connected with the reactor and is used for forming an electric field driving reaction; the voltage and current control assembly is electrically connected with the electric driving unit and is used for controlling the output voltage and the output current of the electric driving unit; the temperature control unit is electrically connected with the reactor and used for measuring and controlling the temperature of the reactor. The catalyst generates an electrothermal effect under the action of an electric field to provide energy, and also generates an electronic effect to promote contact between pollutants and the catalyst, so that efficient catalytic oxidation of carbon monoxide at low temperature is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of air pollution control, and in particular to a device and method for electrically assisted catalytic oxidation of carbon monoxide. Background Art

[0002] CO is an unsaturated metastable molecule that can exist in the atmosphere for a long time. When the CO concentration in the air exceeds 650-700ppm, it will cause death. Catalytic oxidation is one of the most effective methods for removing carbon monoxide. This method reduces the oxidation temperature of carbon monoxide by a catalyst. A few precious metal catalysts can even catalyze the combustion of carbon monoxide at room temperature (Science, 2011, 333, 736-739), but their high prices limit their further application. CN109999658A discloses an electric-driven catalytic reaction device and its application. The device can utilize an electric field to drive the catalytic reaction and is suitable for catalyzing the combustion reaction of air pollutants, including the oxidation of carbon monoxide, but the conductive catalyst used contains more than 20wt% of precious metal silver, and the production cost is relatively high. Summary of the invention

[0003] In order to solve at least one technical problem in the background technology, the present invention provides a device and method for electrically assisted catalytic oxidation of carbon monoxide, which utilizes the electrothermal effect generated by the catalyst under the action of the electric field to provide energy, and also generates an electronic effect to promote the contact between pollutants and the catalyst, thereby achieving efficient catalytic oxidation of carbon monoxide at low temperature.

[0004] To achieve the above-mentioned purpose, the present invention provides a device for electrically assisted catalytic oxidation of carbon monoxide, comprising: a shell, a reactor, an electric drive unit, a voltage and current control component and a temperature control unit; the reactor, the electric drive unit and the temperature control unit are all arranged inside the shell; an air inlet pipe and an air outlet pipe are provided at both ends of the shell, and the air inlet pipe and the air outlet pipe are both provided with exhaust / blowing devices, and the air inlet pipe and the air outlet pipe of the shell are connected to the air inlet and the air outlet of the reactor; the electric drive unit is electrically connected to the reactor for forming an electric field driven reaction; the voltage and current control component is electrically connected to the electric drive unit for controlling the output voltage and output current of the electric drive unit; the temperature control unit is electrically connected to the reactor for measuring and controlling the temperature of the reactor.

[0005] Furthermore, the reactor includes a quartz tube, a catalyst is placed in the center of the quartz tube, the catalyst is fixed by metal collectors on both sides, the metal collectors on both sides are respectively connected to two stainless steel electrodes, the outer side of the quartz tube is wrapped by an insulation layer, and a heating resistor is arranged in the insulation layer.

[0006] Furthermore, the electric drive unit includes a transformer and a rectifier circuit, a filter circuit, a voltage stabilizing circuit and a cooling fan; the cooling fan is located on one side of the electric drive unit, the transformer and the rectifier circuit, the filter circuit, and the voltage stabilizing circuit are connected in sequence, and the output terminals of the electric drive unit are respectively connected to the heating resistor and the stainless steel electrode.

[0007] Furthermore, the temperature control unit includes a temperature control chip, a temperature measurement module, a clock module, a button module, a display module and a communication module, and the temperature measurement module, clock module, button module, display module and communication module are all electrically connected to the temperature control chip; the temperature measurement module is electrically connected to the thermocouple on one side of the metal current collector.

[0008] Furthermore, the thermal insulation material of the thermal insulation layer includes glass fiber, asbestos or rock wool, and the material of the heating resistor includes nickel-chromium alloy, copper-nickel alloy or tungsten.

[0009] A method for electrically assisted catalytic oxidation of carbon monoxide comprises the following steps:

[0010] S1, reaction system;

[0011] S1.1. The reaction device includes a reactor, an electric drive unit, a voltage and current control component and a temperature control unit;

[0012] S1.2, the reactor includes a quartz tube, a catalyst is placed in the center of the quartz tube, the catalyst is fixed by metal current collectors on both sides, the metal current collectors on both sides are respectively connected to two stainless steel electrodes, and the size of the reactor is specifically designed according to actual needs;

[0013] S1.3, the electric drive unit is electrically connected to the electrode, one side of the electrode extends into the quartz tube to contact the metal current collector and form an electric field driven reaction;

[0014] S1.4, the temperature control unit is electrically connected to a thermocouple located near the contact point between the electrode and the metal current collector;

[0015] S2, preparing a catalyst;

[0016] S2.1. The catalyst is synthesized by sol-gel self-propagating combustion method. The precursors of the catalyst components are: Mn(NO3)2, Co(NO3)2·6H2O, La(NO3)3·6H2O, Sr(NO3)2·6H2O; the molar ratio of Mn(NO3)2 / Co(NO3)2·6H2O is in the range of 0.1-2:1, and the molar ratio of La to the sum of the remaining metal atoms is 1:1; citric acid is dissolved in water, and the molar ratio of citric acid to the sum of metal atoms is 1-1.5:1, i.e., complexing agent solution B;

[0017] S2.2, slowly mix the precursor solution A and the complexing agent solution B in a ratio of 1:1 in deionized water and heat and stir thoroughly;

[0018] S2.3, transfer the mixed solution to a forced air drying oven at 200°C to obtain a dry gel powder, and then calcine in a muffle furnace at 400-700°C for 3-6h to obtain a catalyst;

[0019] S3. Carbon monoxide and oxygen are introduced into the reactor, and the electrothermal effect generated by the electric field is used to provide energy, and the electronic effect is also generated to promote the contact between pollutants and catalysts, thereby achieving efficient catalytic oxidation of carbon monoxide at low temperature.

[0020] Further, in step S2.3, a conductive aid is added to part of the obtained catalyst by mechanical mixing, and the conductive aid includes conductive carbon black, carbon nanotubes or expanded graphite;

[0021] S2.3.1. After obtaining the catalyst, the catalyst and the aforementioned conductive additive are fully mixed and ground by mechanical mixing in a ratio of 0-10wt% by mass;

[0022] S2.3.2. Press the ground sample into tablets at a pressure of 20 MPa and collect catalyst particles of 40-60 mesh.

[0023] Furthermore, in step S2.3, a current is passed through a part of the catalyst to heat the catalyst to generate an electrothermal effect and an electronic effect, and the temperature of the conductive catalyst is regulated by controlling the electric power, and the input value of the electric power is 1 to 12W.

[0024] Furthermore, in step S2.2, the stirring time is not less than 6 hours; in step S2.3, the heating efficiency is 1-3°C / min.

[0025] The beneficial effects of the present invention are:

[0026] The present invention utilizes the electrothermal effect generated by the catalyst under the action of the electric field to provide energy, and also generates an electronic effect to promote the contact between pollutants and the catalyst, thereby achieving efficient catalytic oxidation of carbon monoxide at low temperature. It can reduce the dependence on external heating sources, and even eliminate the need for external heating sources, thereby reducing energy loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of the present invention;

[0028] Figure 2 It is a structural schematic diagram of the reactor of the present invention;

[0029] Figure 3 2. It is a comparative schematic diagram of the test of the conductivity performance of catalysts with the preferred mixing ratio of the conductive additives of the present invention;

[0030] Figure 4 1 is a schematic diagram comparing the performance tests of the electrically assisted catalysis in Examples 1-3 of the present invention and the thermal catalytic oxidation of carbon monoxide in Comparative Example 1;

[0031] Figure 5 1. It is a comparative schematic diagram of the performance test of the electrothermal catalysis in Examples 4-6 of the present invention and the thermal catalytic oxidation of carbon monoxide in Comparative Examples 2-4;

[0032] Figure 6 It is a schematic diagram of the reaction rate test of carbon monoxide electrocatalyzed by the catalyst at different electrical powers in Examples 4-6 of the present invention.

[0033] Among them, in the figure:

[0034] 1-thermocouple, 2-electrode, 3-insulation layer, 4-metal current collector, 5-catalyst, 6-quartz tube, 7-heating resistor, 8-shell, 9-inlet pipe, 10-outlet pipe, 11-voltage and current control component, 12-electric drive unit, 13-temperature control unit, 14-rectifier circuit, 15-filter circuit, 16-voltage stabilizing circuit, 17-output terminal, 18-cooling fan, 19-temperature control chip, 20-temperature measurement module, 21-clock module, 22-button module, 23-display module, 24-communication module, 25-exhaust / blowing device, 26-transformer. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0037] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0038] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0039] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0040] In view of the deficiencies in the prior art, after long-term research and a large number of repeated experiments, it was found that electrical assistance can help catalysts to efficiently catalyze the oxidation of carbon monoxide at low temperatures. On the one hand, the electric field promotes the migration of lattice oxygen in the catalyst, thereby enhancing its catalytic effect; on the other hand, the carriers (electrons) excited by the electric field activate the surface adsorbed molecules and promote the reaction, so the technical solution of the present invention is proposed. The technical solution, its implementation process and principle will be further explained as follows.

[0041] To achieve the above purpose, Figure 1-2As shown, the present invention provides a device for electrically assisted catalytic oxidation of carbon monoxide, comprising: a shell 8, a reactor, an electric drive unit 12, a voltage and current control component 11 and a temperature control unit 13; the reactor, the electric drive unit 12 and the temperature control unit 13 are all arranged inside the shell 8; an air inlet pipe 9 and an air outlet pipe 10 are provided at both ends of the shell 8, and the air inlet pipe 9 and the air outlet pipe 10 are both provided with an exhaust / blowing device 25, and the air inlet pipe 9 and the air outlet pipe 10 of the shell 8 are connected to the air inlet and the air outlet of the reactor; the electric drive unit 12 is electrically connected to the reactor for forming an electric field driven reaction; the voltage and current control component 11 is electrically connected to the electric drive unit 12 for controlling the output voltage and output current of the electric drive unit 12; the temperature control unit 13 is electrically connected to the reactor for measuring and controlling the temperature of the reactor.

[0042] To further optimize the technical solution, the reactor includes a quartz tube 6, a catalyst 5 is placed in the center of the quartz tube 6, the catalyst 5 is fixed by metal current collectors 4 on both sides, the metal current collectors 4 on both sides are respectively connected to two stainless steel electrodes 2, the outer side of the quartz tube 6 is wrapped by a thermal insulation layer 3, and a heating resistor 7 is arranged in the thermal insulation layer 3. The heating resistor 7 and the thermal insulation layer 3 are wrapped by a metal shell, and the shell material can be stainless steel.

[0043] Further optimizing the technical solution, the electric drive unit 12 includes a transformer 26 and a rectifier circuit 14, a filter circuit 15, a voltage regulator circuit 16 and a cooling fan 18; the cooling fan 18 is located on one side of the electric drive unit 12, the transformer 26 and the rectifier circuit 14, the filter circuit 15, and the voltage regulator circuit 16 are connected in sequence, and the output terminal 17 of the electric drive unit 12 is respectively connected to the heating resistor 7 and the stainless steel electrode 2. The power supply of the electric drive unit 12 needs to meet the AC input voltage: 220V 50 / 60Hz, the output DC voltage range is 0-60V, and the DC current range is 0-3A.

[0044] To further optimize the technical solution, the temperature control unit 13 includes a temperature control chip 19, a temperature measurement module 20, a clock module 21, a button module 22, a display module 23 and a communication module 24, and the temperature measurement module 20, the clock module 21, the button module 22, the display module 23 and the communication module 24 are all electrically connected to the temperature control chip 19; the temperature measurement module 20 is electrically connected to the thermocouple 1 on one side of the metal current collector 4.

[0045] To further optimize the technical solution, the insulation material of the insulation layer 3 includes glass fiber, asbestos or rock wool, and the material of the heating resistor 7 includes nickel-chromium alloy, copper-nickel alloy or tungsten.

[0046] The present invention also provides a method for electrically assisted catalytic oxidation of carbon monoxide, comprising the following steps:

[0047] S1, reaction system;

[0048] S1.1. The reaction device includes a reactor, an electric drive unit, a voltage and current control component and a temperature control unit;

[0049] S1.2, the reactor includes a quartz tube, a catalyst is placed in the center of the quartz tube, the catalyst is fixed by metal current collectors on both sides, the metal current collectors on both sides are respectively connected to two stainless steel electrodes, and the size of the reactor is specifically designed according to actual needs;

[0050] S1.3, the electric drive unit is electrically connected to the electrode, one side of the electrode extends into the quartz tube to contact the metal current collector and form an electric field driven reaction;

[0051] S1.4, the temperature control unit is electrically connected to a thermocouple located near the contact point between the electrode and the metal current collector;

[0052] S2, preparing a catalyst;

[0053] S2.1. The catalyst is synthesized by sol-gel self-propagating combustion method. The precursors of the catalyst components are: Mn(NO3)2, Co(NO3)2·6H2O, La(NO3)3·6H2O, Sr(NO3)2·6H2O; the molar ratio of Mn(NO3)2 / Co(NO3)2·6H2O is in the range of 0.1-2:1, and the molar ratio of La to the sum of the remaining metal atoms is 1:1; citric acid is dissolved in water, and the molar ratio of citric acid to the sum of metal atoms is 1-1.5:1, i.e., complexing agent solution B;

[0054] S2.2, slowly mix the precursor solution A and the complexing agent solution B in a ratio of 1:1 in deionized water and heat and stir thoroughly;

[0055] S2.3, transfer the mixed solution to a forced air drying oven at 200°C to obtain a dry gel powder, and then calcine in a muffle furnace at 400-700°C for 3-6h to obtain a catalyst;

[0056] S3. Carbon monoxide and oxygen are introduced into the reactor, and the electrothermal effect generated by the electric field is used to provide energy, and the electronic effect is also generated to promote the contact between pollutants and catalysts, thereby achieving efficient catalytic oxidation of carbon monoxide at low temperature.

[0057] The oxide catalyst itself has a certain conductivity, and can achieve a path under a certain voltage, generate current, and further catalyze the oxidation of carbon monoxide through electrothermal effect and electronic effect. The addition of conductive additives can improve the conductivity of the catalyst and stabilize the voltage across the catalyst, thereby carrying a stable electric field and even breaking away from the limitations of external heat sources.

[0058] Further optimizing the technical solution, in step S2.3, a conductive additive is added to part of the catalyst obtained by mechanical mixing, and the conductive additive includes conductive carbon black, carbon nanotubes or expanded graphite;

[0059] S2.3.1. After obtaining the catalyst, the catalyst and the aforementioned conductive additive are fully mixed and ground by mechanical mixing in a ratio of 0-10wt% by mass;

[0060] S2.3.2. Press the ground sample into tablets at a pressure of 20 MPa and collect catalyst particles of 40-60 mesh.

[0061] To further optimize the technical solution, in step S2.3, current is passed through part of the catalyst to heat the catalyst to produce electrothermal effect and electronic effect, and the temperature of the conductive catalyst is regulated by controlling the electric power, and the input value of the electric power is 1 to 12W.

[0062] The technical solution was further optimized. In step S2.2, the stirring time was no less than 6 h to ensure sufficient stirring effect. In step S2.3, the heating efficiency was 1-3 °C / min, and the temperature was raised steadily and gradually to ensure complete oxidation of the organic complex and avoid affecting subsequent experiments.

[0063] The present invention utilizes the electrothermal effect generated by the catalyst under the action of the electric field to provide energy, and also generates an electronic effect to promote the contact between the pollutant and the catalyst, thereby achieving efficient catalytic oxidation of carbon monoxide at low temperature. It can reduce the dependence on external heating sources, and even eliminate the need for external heating sources, thereby reducing energy loss. The present invention can be used for purification of small enclosed spaces, and can also be used as a reference for small industrial devices.

[0064] Example 1

[0065] Using nitrogen as carrier gas, 0.1 vol% carbon monoxide gas is introduced, and the volume ratio of carbon monoxide to oxygen is 1:200. The outlet gas composition is detected by a flue gas analyzer, and the activity of the catalyst is evaluated under electrical assistance (input current = 10 mA). Catalyst 1# (hereinafter marked as catalyst 1#-10mA) is loaded into the center of the quartz tube 6, and its two ends are tightly clamped by the metal current collector 4. Two stainless steel threaded rods are used as electrodes 2 to contact the two metal current collectors 4 respectively, and the other ends pass through a tee and are fixed with a rubber stopper. A K-type thermocouple 1 is inserted into the rubber stopper, and its top end is placed next to the contact between the stainless steel electrode 2 and the metal current collector 4 to measure the temperature. The two ends of the stainless steel electrode 2 are respectively connected to the positive and negative poles of a DC power supply. Figure 4 The performance test results of electrocatalytic carbon monoxide at different temperatures under different electrocatalytic conditions are shown; see Figure 4The reaction results showed that under the condition of input current of 10 mA (the catalyst bed temperature was maintained at 60°C by an external field), the carbon monoxide conversion rate reached 48.9%.

[0066] Example 2

[0067] Using nitrogen as carrier gas, 0.1 vol% carbon monoxide gas is introduced, and the volume ratio of carbon monoxide to oxygen is 1:200. The outlet gas composition is detected by a flue gas analyzer, and the activity of the catalyst is evaluated under electrical assistance (input current = 20 mA). The 1# catalyst (hereinafter marked as 1#-20mA catalyst) is loaded into the center of the quartz tube 6, and its two ends are tightly clamped by the metal current collector 4. Two stainless steel threaded rods are used as electrodes 2 to contact the two metal current collectors 4 respectively, and the other ends pass through a tee and are fixed with a rubber stopper. A K-type thermocouple 1 is inserted into the rubber stopper, and its top end is placed next to the contact between the stainless steel electrode 2 and the metal current collector 4 to measure the temperature. The two ends of the stainless steel electrode 2 are respectively connected to the positive and negative poles of a DC power supply. Figure 4 The performance test results of electrocatalytic carbon monoxide at different temperatures under different electrocatalytic conditions are shown; see Figure 4 The reaction results showed that under the condition of an input current of 20 mA (the catalyst bed temperature was maintained at 60°C by an external field), the carbon monoxide conversion rate reached 65.3%.

[0068] Example 3

[0069] Using nitrogen as the carrier gas, 0.1 vol% carbon monoxide gas is introduced, and the volume ratio of carbon monoxide to oxygen is 1:200. The outlet gas composition is detected by a flue gas analyzer, and the activity of the catalyst is evaluated under electrical assistance (without external heating source). Catalyst 1# (hereinafter marked as ET-1# catalyst) is loaded into the center of the quartz tube 6, and its two ends are tightly clamped by the metal current collector 4. Two stainless steel threaded rods are used as electrodes 2 to contact the two metal current collectors 4 respectively, and the other ends pass through a tee and are fixed with a rubber stopper. A K-type thermocouple 1 is inserted into the rubber stopper, and its top end is placed next to the contact between the stainless steel electrode 2 and the metal current collector 4 to measure the temperature. The two ends of the stainless steel electrode 2 are respectively connected to the positive and negative poles of a DC power supply. Figure 4 The performance test results of electrocatalytic carbon monoxide at different temperatures under different electrocatalytic conditions are shown; see Figure 4 The reaction results showed that when the catalyst bed temperature was maintained at 60°C under electrically assisted conditions, the carbon monoxide conversion rate reached 75.4%.

[0070] Example 4

[0071] Using nitrogen as carrier gas, 0.1 vol% carbon monoxide gas is introduced, and the volume ratio of carbon monoxide to oxygen is 1:200. The outlet gas composition is detected by a flue gas analyzer, and the activity of the catalyst is evaluated under electric heating. Catalyst 2# (hereinafter marked as ET-2# catalyst) is loaded into the center of the quartz tube 6, and its two ends are tightly clamped by the metal current collector 4. Two stainless steel threaded rods are used as electrodes 2 to contact the two metal current collectors 4 respectively, and the other ends pass through a tee and are fixed with a rubber stopper. A K-type thermocouple 1 is inserted into the rubber stopper, and its top end is placed next to the contact between the stainless steel electrode 2 and the metal current collector 4 to measure the temperature. The two ends of the stainless steel electrode 2 are connected to the positive and negative poles of a DC power supply respectively. The input power is controlled by a software program, and the control conditions are: each temperature is maintained for 40 minutes in the range of 1-12W. Figure 1 The performance test results of electrothermal catalytic carbon monoxide at different temperatures are shown; see Figure 6 The reaction results showed that under the condition of input power of 5W (catalyst bed temperature of 160℃), the carbon monoxide conversion rate reached 0.30μmol / (g·s).

[0072] Example 5

[0073] Argon was used as a carrier gas, and 0.1 vol% carbon monoxide gas was introduced, with a volume ratio of carbon monoxide to oxygen of 1:200. The outlet gas composition was detected by a flue gas analyzer, and the activity of the lanthanide perovskite catalyst was evaluated under electric heating. Catalyst 3# (hereinafter marked as ET-3# catalyst) was loaded into the center of the quartz tube 6, and its two ends were tightly clamped by the metal current collector 4. Two stainless steel threaded rods were used as electrodes 2 to contact the two metal current collectors 4 respectively, and the other ends passed through a tee and fixed with a rubber stopper. A K-type thermocouple 1 was inserted into the rubber stopper, and its top end was placed next to the contact between the stainless steel electrode 2 and the metal current collector 4 to measure the temperature. The two ends of the stainless steel electrode 2 were connected to the positive and negative poles of a DC power supply, respectively. The input power was controlled by a software program, and the control conditions were: each temperature was maintained for 40 minutes in the range of 1-12W. Figure 1 The performance test results of electrothermal catalytic carbon monoxide at different temperatures are shown; see Figure 6 The reaction results showed that under the condition of input power of 5W (catalyst bed temperature of 160℃), the carbon monoxide conversion rate reached 0.56μmol / (g·s).

[0074] Example 6

[0075] Argon was used as a carrier gas, and 0.1 vol% carbon monoxide gas was introduced, with a volume ratio of carbon monoxide to oxygen of 1:200. The outlet gas composition was detected by a flue gas analyzer, and the activity of the lanthanide perovskite catalyst was evaluated under electric heating. Catalyst 4# (hereinafter marked as ET-4# catalyst) was loaded into the center of the quartz tube 6, and its two ends were tightly clamped by the metal current collector 4. Two stainless steel threaded rods were used as electrodes 2 to contact the two metal current collectors 4 respectively, and the other ends passed through a tee and fixed with a rubber stopper. A K-type thermocouple 1 was inserted into the rubber stopper, and its top end was placed next to the contact between the stainless steel electrode 2 and the metal current collector 4 to measure the temperature. The two ends of the stainless steel electrode 2 were connected to the positive and negative poles of a DC power supply, respectively. The input power was controlled by a software program, and the control conditions were: each temperature was maintained for 40 minutes in the range of 1-12W. Figure 1 The performance test results of electrothermal catalytic carbon monoxide at different temperatures are shown; see Figure 6 The reaction results showed that under the condition of input power of 5W (catalyst bed temperature of 160℃), the carbon monoxide conversion rate reached 0.66μmol / (g·s).

[0076] Comparative Example 1

[0077] The sample #1 in Example 1 was placed in a common thermal catalytic fixed bed reactor. Nitrogen was used as the carrier gas, and 0.1 vol% carbon monoxide gas was introduced. The volume ratio of carbon monoxide to oxygen was 1:200. The outlet gas composition was detected by a flue gas analyzer. By comparing the performance of the electric-assisted catalysis of Example 1 and the thermal catalytic oxidation of carbon monoxide in the similar temperature range, please refer to Figure 4 It can be seen that the method of electrically assisted catalytic oxidation of carbon monoxide significantly reduces the ignition temperature of carbon monoxide and can achieve efficient catalytic oxidation of carbon monoxide.

[0078] Comparative Example 2

[0079] The sample 2# in Example 4 was placed in a common thermal catalytic fixed bed reactor. Nitrogen was used as the carrier gas, and 0.1 vol% carbon monoxide gas was introduced. The volume ratio of carbon monoxide to oxygen was 1:200. The outlet gas composition was detected by a flue gas analyzer. By comparing the performance of the electric thermal catalysis of Example 4 and the thermal catalytic oxidation of carbon monoxide in the similar temperature range, please refer to Figure 5 It can be seen that the method of electrothermal catalytic oxidation of carbon monoxide significantly reduces the ignition temperature of carbon monoxide and can achieve efficient catalytic oxidation of carbon monoxide.

[0080] Comparative Example 3

[0081] Sample 3# in Example 5 was placed in a common thermal catalytic fixed bed reactor. Nitrogen was used as carrier gas, and 0.1 vol% carbon monoxide gas was introduced. The volume ratio of carbon monoxide to oxygen was 1:200. The outlet gas composition was detected by a flue gas analyzer. By comparing the performance of the electric thermal catalysis of Example 5 and the thermal catalytic oxidation of carbon monoxide in a similar temperature range, please refer to Figure 5 It can be seen that the method of electrothermal catalytic oxidation of carbon monoxide significantly reduces the ignition temperature of carbon monoxide and can achieve efficient catalytic oxidation of carbon monoxide.

[0082] Comparative Example 4

[0083] Sample 4# in Example 6 was placed in a common thermal catalytic fixed bed reactor. Nitrogen was used as carrier gas, and 0.1 vol% carbon monoxide gas was introduced. The volume ratio of carbon monoxide to oxygen was 1:200. The outlet gas composition was detected by a flue gas analyzer. By comparing the performance of the electric thermal catalysis of Example 6 and the thermal catalytic oxidation of carbon monoxide in the similar temperature range, please refer to Figure 5 It can be seen that the method of electrothermal catalytic oxidation of carbon monoxide significantly reduces the ignition temperature of carbon monoxide and can achieve efficient catalytic oxidation of carbon monoxide.

[0084] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A device for electrically assisted catalytic oxidation of carbon monoxide, characterized in that: include: A shell, a reactor, an electric drive unit, a voltage and current control component and a temperature control unit; the reactor, the electric drive unit and the temperature control unit are all arranged inside the shell; an air inlet pipe and an air outlet pipe are arranged at both ends of the shell, and the air inlet pipe and the air outlet pipe are both provided with an exhaust / blowing device, and the air inlet pipe and the air outlet pipe of the shell are connected with the air inlet and the air outlet of the reactor; the electric drive unit is electrically connected to the reactor to form an electric field driven reaction; the voltage and current control component is electrically connected to the electric drive unit to control the output voltage and output current of the electric drive unit; the temperature control unit is electrically connected to the reactor to measure and control the temperature of the reactor.

2. The device for electrically assisted catalytic oxidation of carbon monoxide according to claim 1, characterized in that: The reactor comprises a quartz tube, a catalyst is placed in the center of the quartz tube, the catalyst is fixed by metal current collectors on both sides, the metal current collectors on both sides are respectively connected to two stainless steel electrodes, the outer side of the quartz tube is wrapped by a heat preservation layer, and a heating resistor is arranged in the heat preservation layer.

3. The device for electrically assisted catalytic oxidation of carbon monoxide as claimed in claim 2, characterized in that: The electric drive unit includes a transformer and a rectifier circuit, a filter circuit, a voltage stabilizing circuit and a cooling fan; the cooling fan is located on one side of the electric drive unit, the transformer and the rectifier circuit, the filter circuit and the voltage stabilizing circuit are connected in sequence, and the output terminals of the electric drive unit are respectively connected to the heating resistor and the stainless steel electrode.

4. The device for electrically assisted catalytic oxidation of carbon monoxide as claimed in claim 3, characterized in that: The temperature control unit includes a temperature control chip, a temperature measurement module, a clock module, a button module, a display module and a communication module. The temperature measurement module, the clock module, the button module, the display module and the communication module are all electrically connected to the temperature control chip; the temperature measurement module is electrically connected to the thermocouple on one side of the metal current collector.

5. The device for electrically assisted catalytic oxidation of carbon monoxide as claimed in claim 2, characterized in that: The heat-insulating material of the heat-insulating layer includes glass fiber, asbestos or rock wool, and the material of the heating resistor includes nickel-chromium alloy, copper-nickel alloy or tungsten.

6. A method for electrically assisted catalytic oxidation of carbon monoxide, characterized in that: The following steps are involved: S1, reaction system; S1.

1. The reaction device includes a reactor, an electric drive unit, a voltage and current control component and a temperature control unit; S1.2, the reactor includes a quartz tube, a catalyst is placed in the center of the quartz tube, the catalyst is fixed by metal current collectors on both sides, the metal current collectors on both sides are respectively connected to two stainless steel electrodes, and the size of the reactor is specifically designed according to actual needs; S1.3, the electric drive unit is electrically connected to the electrode, one side of the electrode extends into the quartz tube to contact the metal current collector and form an electric field driven reaction; S1.4, the temperature control unit is electrically connected to a thermocouple located near the contact point between the electrode and the metal current collector; S2, preparing a catalyst; S2.

1. The catalyst is synthesized by sol-gel self-propagating combustion method. The precursors of the catalyst components are: Mn(NO3)2, Co(NO3)2·6H2O, La(NO3)3·6H2O, Sr(NO3)2·6H2O; the molar ratio of Mn(NO3)2 / Co(NO3)2·6H2O is in the range of 0.1-2:1, and the molar ratio of La to the sum of the remaining metal atoms is 1:1; citric acid is dissolved in water, and the molar ratio of citric acid to the sum of metal atoms is 1-1.5:1, i.e., complexing agent solution B; S2.2, slowly mix the precursor solution A and the complexing agent solution B in a ratio of 1:1 in deionized water and heat and stir thoroughly; S2.3, transfer the mixed solution to a forced air drying oven at 200°C to obtain a dry gel powder, and then calcine in a muffle furnace at 400-700°C for 3-6h to obtain a catalyst; S3. Carbon monoxide and oxygen are introduced into the reactor, and the electrothermal effect generated by the electric field is used to provide energy, and the electronic effect is also generated to promote the contact between pollutants and catalysts, thereby achieving efficient catalytic oxidation of carbon monoxide at low temperature.

7. The method for electrically assisted catalytic oxidation of carbon monoxide according to claim 6, characterized in that: In step S2.3, a conductive additive is added to part of the obtained catalyst by mechanical mixing, and the conductive additive includes conductive carbon black, carbon nanotubes or expanded graphite; S2.3.

1. After obtaining the catalyst, the catalyst and the aforementioned conductive additive are fully mixed and ground by mechanical mixing in a ratio of 0-10wt% by mass; S2.3.

2. Press the ground sample into tablets at a pressure of 20 MPa and collect catalyst particles of 40-60 mesh.

8. The method for electrically assisted catalytic oxidation of carbon monoxide according to claim 7, characterized in that: In step S2.3, current is passed through part of the catalyst to heat the catalyst to produce electrothermal effect and electronic effect, and the temperature of the conductive catalyst is regulated by controlling the electric power, and the input value of the electric power is 1 to 12W.

9. The method for electrically assisted catalytic oxidation of carbon monoxide according to claim 8, characterized in that: In step S2.2, the stirring time is not less than 6 hours; in step S2.3, the heating efficiency is 1-3°C / min.

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