Device and method for producing hydrogen and carbon materials by catalyzing methane through DBD discharge

Abstract

The invention relates to the technical field of environmental pollution prevention and control and material preparation, and discloses a device and method for producing hydrogen and a carbon material by catalyzing methane through DBD discharge. The reactor comprises a first insulating medium of a cylindrical structure, a reaction cavity is formed in the first insulating medium, the two ends of the reaction cavity are communicated with an air inlet and an air outlet respectively, the air inlet is communicated with reactants, the outer surface of the first insulating medium is coated with an outer electrode, an inner electrode is arranged in the reaction cavity, and the inner electrode is coated with a second insulating medium. A gap between the first insulating medium and the second insulating medium is used for filling a catalyst; the collector is communicated with the air outlet; according to the invention, high-value conversion of non-two greenhouse gases can be realized, the temperature is low, the hydrogen production efficiency is high, the selectivity for producing high-value carbon products is good, and meanwhile, zero emission of CO2 is realized.

Description

Technical Field

[0001] The invention relates to the technical field of environmental pollution prevention and control and material preparation, and in particular to a device and method for DBD discharge catalytic methane production of hydrogen and carbon materials. Background Art

[0003] Traditional methane hydrogen production technologies mainly include methane steam reforming, methane carbon dioxide reforming, methane partial oxidation, methane autothermal reforming and methane catalytic cracking, etc. These methods are mainly carried out in a thermal catalytic manner. Since methane molecules are highly stable and CH bonds are difficult to break, thermal catalytic reactions require high temperatures to provide sufficient energy, and are often accompanied by large amounts of carbon dioxide emissions. The added value of the resulting carbon materials is also low.

[0004] Therefore, there is an urgent need for a device and method for DBD discharge catalytic methane production of hydrogen and carbon materials. Summary of the invention

[0005] The object of the present invention is to provide a device and method for producing hydrogen and carbon materials from methane by DBD discharge catalysis, aiming to solve or improve at least one of the above-mentioned technical problems.

[0006] To achieve the above object, the present invention provides the following solution: The present invention provides a device for DBD discharge catalytic methane production of hydrogen and carbon materials, comprising:

[0007] an air intake system for delivering reactants;

[0008] A reactor, comprising a first insulating medium of a cylindrical structure, a reaction chamber is formed inside the first insulating medium, an air inlet and an air outlet are respectively connected at two ends of the reaction chamber, the air inlet is connected to the reactant, an outer surface of the first insulating medium is coated with an outer electrode, an inner electrode is arranged in the reaction chamber, a second insulating medium is coated on the inner electrode, and a gap between the first insulating medium and the second insulating medium is used to fill a catalyst;

[0009] a collector, connected to the gas outlet;

[0010] A plasma power supply is connected to the inner electrode and the outer electrode.

[0011] Optionally, the air intake system includes a mixer and a methane gas source and an inert gas source connected to the mixer.

[0012] Optionally, a mass flow meter is provided between the mixer and the methane gas source and the inert gas source.

[0013] Optionally, the collector includes a shell and a first air port, a second air port and a third air port provided on the shell, the second air port is connected to the air outlet, the first air port is connected to an external storage device or the atmosphere, and the third air port is detachably connected to a sampling plug.

[0014] Optionally, the outer electrode is coated on the outer side wall of the first insulating medium through a plurality of copper hoops.

[0015] Optionally, porous plugs are respectively provided at both ends of the first insulating medium.

[0016] Optionally, sealing devices covering the porous plug are respectively provided at both ends of the first insulating medium.

[0017] Optionally, the inner electrode is coaxially arranged with the first insulating medium.

[0018] Optionally, the catalyst includes a plurality of carriers and a catalytic medium disposed in the carriers.

[0019] The present invention also provides a method for producing hydrogen and carbon materials from methane by DBD discharge catalysis, comprising the following steps:

[0020] preparing the catalyst and filling the catalyst into the reaction chamber;

[0021] The reactant is introduced into the reaction chamber from the air inlet through the air inlet system, so that a gas to be reacted is formed in the reaction chamber;

[0022] The plasma power source is used to discharge the inner electrode and the outer electrode to catalyze the gas to be reacted to produce hydrogen and carbon materials. The hydrogen is discharged into the collector through the gas outlet and collected, and the carbon materials are accumulated on the catalyst surface.

[0023] The present invention discloses the following technical effects: reactants are introduced into a reaction chamber through an air intake system, an inner electrode and an outer electrode are discharged through a plasma power supply to catalyze the reactants to form hydrogen and carbon materials, hydrogen is introduced into a collector for collection, and carbon materials are accumulated on the surface of the catalyst. In the discharge catalytic process, a first insulating medium and a second insulating medium are provided between the inner electrode and the outer electrode for isolation, and a dielectric barrier discharge is used to excite high-energy low-temperature plasma to efficiently prepare hydrogen from methane and generate high-value carbon materials at the same time, thereby realizing high-value conversion of non-dihydrogen greenhouse gases, with low temperature, high hydrogen production efficiency, good selectivity for producing high-value carbon products, and realizing CO 2 Zero emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0025] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 It is a schematic diagram of the reactor structure of the present invention;

[0027] Figure 3 It is a schematic diagram of the collector structure of the present invention.

[0028] In the figure: 1. Reactor; 11. Air inlet; 12. Air outlet; 13. Inner electrode; 14. Outer electrode; 15. Catalyst; 16. First insulating medium; 17. Copper hoop; 18. Porous plug; 19. Sealing device; 20. Second insulating medium; 2. Collector; 21. First air port; 22. Second air port; 23. Third air port; 3. Plasma power supply; 4. Mixer; 5. Methane gas source; 6. Inert gas source; 7. Mass flow meter. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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.

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Reference Figure 1-Figure 3 The present invention provides a device for producing hydrogen and carbon materials from methane by DBD discharge catalysis, comprising:

[0032] an air intake system for delivering reactants;

[0033] The reactor 1 comprises a first insulating medium 16 of a cylindrical structure, a reaction chamber is formed inside the first insulating medium, an air inlet 11 and an air outlet 12 are respectively connected at both ends of the reaction chamber, the air inlet 11 is connected to the reactants, an outer surface of the first insulating medium 16 is coated with an outer electrode 14, an inner electrode 13 is arranged in the reaction chamber, and a second insulating medium 20 is coated on the inner electrode, and a gap between the first insulating medium 16 and the second insulating medium 20 is used to fill a catalyst 15;

[0034] The collector 2 is connected to the gas outlet 12;

[0035] The plasma power supply 3 is connected to the inner electrode 13 and the outer electrode 14 .

[0036] The reactants are introduced into the reaction chamber through the air intake system, and the inner electrode 13 and the outer electrode 14 are discharged through the plasma power supply 3 to catalyze the reactants to form hydrogen and carbon materials. The hydrogen is introduced into the collector 2 for collection, and the carbon materials are accumulated on the surface of the catalyst. In the discharge catalytic process, the first insulating medium 16 and the second insulating medium 20 are arranged between the inner electrode 13 and the outer electrode 14 for isolation, and the dielectric barrier discharge is used to excite the high-energy low-temperature plasma to efficiently prepare hydrogen from methane and generate high-value carbon materials at the same time, thereby realizing the high-value conversion of non-two greenhouse gases, with low temperature, high hydrogen production efficiency, good selectivity for producing high-value carbon products, and achieving CO 2 Zero emissions.

[0037] Furthermore, the first insulating medium 16 and the second insulating medium 20 are preferably made of one of quartz, corundum, alumina ceramics, zirconia ceramics, silicon nitride ceramics, silicon carbide ceramics, etc. The materials of the two may be the same or different.

[0038] Furthermore, the gap between the first insulating medium 16 and the second insulating medium 20 is 2-10 mm.

[0039] Furthermore, the reactant may be pure methane or a mixture of methane and an inert gas, wherein the inert gas is one or a mixture of nitrogen, helium, and argon.

[0040] In one embodiment of the present invention, the air intake system includes a mixer 4 and a methane gas source 5 and an inert gas source 6 connected to the mixer 4. A mass flow meter 7 is provided between the mixer 4 and the methane gas source 5 and the inert gas source 6.

[0041] The mixer 4 comprises a tank body, two inlets and one outlet. The two inlets are respectively connected to the mass flow meter 7 , and the outlet is connected to the reactor 1 . The tank body of the mixer 4 may be provided with 1 to 4 blades.

[0042] In one embodiment of the present invention, the collector 2 includes a shell and a first air port 21, a second air port 22 and a third air port 23 provided on the shell, the second air port 22 is connected to the air outlet 12, the first air port 21 is connected to an external storage device or the atmosphere, and the third air port 23 is detachably connected to a sampling plug.

[0043] By setting a sampling plug at the third gas port 23, it is possible to sample and test H in the product at any time. 2 Effect of concentration.

[0044] Furthermore, the first gas port 21 , the second gas port 22 and the third gas port 23 are all provided with valves.

[0045] In one embodiment of the present invention, the outer electrode 14 is covered on the outer side wall of the first insulating medium 16 by a plurality of copper hoops 17 .

[0046] In one embodiment of the present invention, porous plugs 18 are respectively disposed at both ends of the first insulating medium 16 .

[0047] The porous plug 18 is made of one of alumina ceramics, silicon carbide ceramics, silicon nitride ceramics, zirconium oxide ceramics, mullite and the like, and the pore size of the porous plug 18 is 0.5-4 mm.

[0048] In one embodiment of the present invention, sealing devices 19 covering porous plugs are respectively provided at both ends of the first insulating medium 16 .

[0049] In one embodiment of the present invention, the inner electrode 13 and the first insulating medium 16 are coaxially arranged.

[0050] In one embodiment of the present invention, the catalyst 15 includes a plurality of carriers and a catalytic medium disposed in the carriers.

[0051] The catalyst 15 carrier is one of alumina balls, zirconia balls, and glass balls. The carrier diameter is 1-4 mm. The catalytic medium is Ni, NiO, Fe, Fe 2 O 3 One of such transition metals or their oxides.

[0052] The filling method of the catalyst 15 in the present invention ensures uniform distribution and a larger surface area of ​​the catalyst 15 while allowing the gas flow to pass smoothly, and at the same time, the porous plug 18 is used to adjust the length of the catalyst 15 filled into the reactor 1 to be consistent with the length of the effective discharge area. Through the specific design of the catalyst 15, the yield and quality of hydrogen and carbon materials are improved, so that the carbon materials have higher added value.

[0053] A method for producing hydrogen and carbon materials from methane by DBD discharge catalysis, comprising the following steps:

[0054] Preparing a catalyst 15 and filling the catalyst 15 into the reaction chamber;

[0055] The reactants are introduced into the reaction chamber from the air inlet 11 through the air inlet system to form a gas to be reacted in the reaction chamber. The air inlet flow rate is 20-200 sccm, the input voltage of the reactor 1 is 5-30 kV, and the frequency is set to 1000-20000 Hz;

[0056] The plasma power supply 3 causes the inner electrode 13 and the outer electrode 14 to discharge to catalyze the reactant gas to produce hydrogen and carbon materials. The hydrogen is discharged into the collector 2 through the gas outlet 12 and collected, and the carbon materials are accumulated on the surface of the catalyst 15.

[0057] Furthermore, during the catalytic process, the reactor 1 can be calcined at 400-600°C for 4-7h at a heating rate of 1-20°C / min in a tubular furnace, and the carrier gas can be N 2 , H 2 NH 3 Or other commonly used carrier gases. Specific implementation 1:

[0059] First, the catalyst 15 was calcined and 11.92 g Ni(NO 3 ) 2 6H 2 O was dissolved in 3.92 g of deionized water and 80.02 g of Al 2 O 3 The mixed material was then dried at 80°C for 8 hours and then placed in a quartz boat under N 2 The catalyst NiO / Al was calcined at 500 °C (10 °C / min) for 4 h under a molten-hydrogen atmosphere to obtain 2 O 3 The porous plug 18 made of mullite, the catalyst 15 and another porous plug 18 made of mullite are sequentially filled into the reactor 1, and the reactor 1 is sealed. Set N 2 Inlet gas flow rate 20 sccm, CH 4 The inlet gas flow rate is 5 sccm, and the flow rate is controlled by a pair of mass flow meters 7. The gas is transported to the mixer 4 through the air pipe, mixed evenly, and flows out from the outlet to the air inlet 11 of the reactor 1. The reactants pass through the first porous plug 18, the catalyst 15 and another porous plug 18 in turn to reach the gas outlet 12 of the reactor 1. The gas is transmitted to the second gas port 22 of the collector 2 through the output pipeline, and the excess gas reaches the external storage device or is discharged to the atmosphere from the first gas port 21 of the collector 2. After 10 minutes of gas input, the reactor 1 is filled with the gas to be reacted as a whole, and the air is completely discharged. At this time, the plasma power supply 4 parameters are set to adjust the input voltage of 15 kV, the frequency of 10000 Hz, the reaction time of 10 minutes, the positive pole of the power supply is connected to the inner electrode 13, and the negative pole of the power supply is connected to the outer electrode 14, and the reaction begins. During the reaction, sampling and testing can be performed at any time from the third gas port 23 of the collector 2, and the product carbon product accumulates on the surface of the catalyst 15. Specific implementation 2:

[0061] First, the catalyst 15 was calcined and 11.92 g Ni(NO 3 ) 2 6H 2 O was dissolved in 3.92 g of deionized water and 80.02 g of Al 2 O 3The mixed material was then dried at 80°C for 8 hours and then placed in a quartz boat under N 2 Calcinated at 500 °C (10 °C / min) for 4 h in H 2 Calcination under atmosphere for 1 h to obtain the catalyst Ni / Al 2 O 3 The porous plug 18 made of mullite, the catalyst 15 and another porous plug 18 made of mullite are sequentially filled into the reactor 1, and the reactor 1 is sealed. Set N 2 Inlet gas flow rate 10 sccm, CH 4 The inlet gas flow rate is 10sccm, and the flow rate is controlled by a pair of mass flow meters 7. The gas is transported to the mixer 4 through the air pipe and mixed evenly. It flows out from the outlet and is transmitted to the air inlet 11 of the reactor 1. The reactants pass through the first porous plug 18, the catalyst 15 and another porous plug 18 in turn to reach the outlet 12. The gas is transmitted to the second gas port 22 of the collector 2 through the output pipeline. The excess gas reaches the external storage device or is discharged to the atmosphere from the first gas port 21 of the collector. After 10 minutes of gas input, the reactor 1 is filled with the gas to be reacted as a whole, and the air is completely discharged. At this time, the plasma power supply 4 parameters are set to adjust the input voltage of 12kV, the frequency of 12000Hz, the reaction time of 15min, the positive pole of the power supply is connected to the inner electrode 13, and the negative pole of the power supply is connected to the outer electrode 14, and the reaction starts. During the reaction, sampling and testing can be carried out at any time from the third gas port 23 of the collector 2, and the product carbon product accumulates on the catalyst surface. Specific implementation 3:

[0063] First, the catalyst 15 was calcined and 11.92 g Ni(NO 3 ) 2 6H 2 O was dissolved in 3.92 g of deionized water and 80.02 g of Al 2 O 3 The mixed material was then dried at 80°C for 8 hours and then placed in a quartz boat under H 2 The catalyst Ni / Al was calcined at 500°C (10°C / min) for 5 h under a molten-gas atmosphere to obtain 2 O 3 -5h. The ceramic porous plug 18, the catalyst 15 and another ceramic porous plug 18 are sequentially placed into the reactor 1, and the reactor 1 is sealed. Set N 2 Inlet gas flow rate 10 sccm, CH 4The inlet gas flow rate is 15sccm, and the flow rate is controlled by a pair of mass flow meters 7. The gas is transported to the mixer 4 through the air pipe, mixed evenly, and flows out from the outlet to the air inlet 11. The reactants pass through the first porous plug 18, the catalyst 15 and another porous plug 18 in turn to reach the reverse outlet 12. The gas is transmitted to the second gas port 22 of the collector 2 through the output pipeline, and the excess gas reaches the external storage device or is discharged to the atmosphere from the first gas port 21 of the collector 2. After 8 minutes of gas input, the reactor 1 is filled with the gas to be reacted as a whole, and the air is completely discharged. At this time, the plasma power supply 4 parameters are set to adjust the input voltage to 20kV, the frequency to 10000Hz, the reaction time to 15min, the positive pole of the power supply is connected to the inner electrode 13, and the negative pole of the power supply is connected to the outer electrode 14, and the reaction begins. During the reaction, sampling and testing can be performed at any time from the third gas port 23 of the collector 2, and the product carbon product accumulates on the catalyst surface.

[0064] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0065] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A device for producing hydrogen and carbon materials from methane by DBD discharge catalysis, characterized in that: include: an air intake system for delivering reactants; A reactor (1), comprising a first insulating medium (16) of a cylindrical structure, a reaction chamber formed inside the first insulating medium, an air inlet (11) and an air outlet (12) respectively connected at two ends of the reaction chamber, the air inlet (11) being connected to the reactant, an outer surface of the first insulating medium (16) being coated with an outer electrode (14), an inner electrode (13) being arranged in the reaction chamber, a second insulating medium (20) being coated on the inner electrode, and a gap between the first insulating medium (16) and the second insulating medium (20) being used to fill a catalyst (15); A collector (2) connected to the gas outlet (12); A plasma power source (3) is connected to the inner electrode (13) and the outer electrode (14).

2. The device for producing hydrogen and carbon materials by DBD discharge catalysis of methane according to claim 1, characterized in that: The air intake system comprises a mixer (4) and a methane gas source (5) and an inert gas source (6) which are connected to the mixer (4).

3. The device for producing hydrogen and carbon materials from methane by DBD discharge catalysis according to claim 2, characterized in that: A mass flow meter (7) is provided between the mixer (4), the methane gas source (5) and the inert gas source (6).

4. The device for producing hydrogen and carbon materials by DBD discharge catalysis of methane according to claim 1, characterized in that: The collector (2) comprises a shell and a first air port (21), a second air port (22) and a third air port (23) provided on the shell, wherein the second air port (22) is connected to the air outlet (12), the first air port (21) is connected to an external storage device or the atmosphere, and the third air port (23) is detachably connected to a sampling plug.

5. The device for producing hydrogen and carbon materials from methane by DBD discharge catalysis according to claim 1, characterized in that: The outer electrode (14) is coated on the outer side wall of the first insulating medium (16) via a plurality of copper hoops (17).

6. The device for producing hydrogen and carbon materials from methane by DBD discharge catalysis according to claim 1, characterized in that: Porous plugs (18) are respectively provided at both ends of the first insulating medium (16).

7. The device for producing hydrogen and carbon materials from methane by DBD discharge catalysis according to claim 6, characterized in that: Sealing devices (19) covering the porous plug are respectively provided at both ends of the first insulating medium (16).

8. The device for producing hydrogen and carbon materials from methane by DBD discharge catalysis according to claim 7, characterized in that: The inner electrode (13) and the first insulating medium (16) are coaxially arranged.

9. The device for producing hydrogen and carbon materials from methane by DBD discharge catalysis according to claim 1, characterized in that: The catalyst (15) comprises a plurality of carriers and a catalytic medium arranged in the carriers.

10. A method for producing hydrogen and carbon materials from methane by DBD discharge catalysis, based on the device for producing hydrogen and carbon materials from methane by DBD discharge catalysis according to any one of claims 1 to 9, characterized in that: The following steps are involved: preparing the catalyst (15) and filling the catalyst (15) into the reaction chamber; The reactant is introduced into the reaction chamber from the air inlet (11) through the air inlet system, so that a gas to be reacted is formed in the reaction chamber; The plasma power supply (3) causes the inner electrode (13) and the outer electrode (14) to discharge to catalyze the gas to be reacted to produce hydrogen and carbon materials. The hydrogen is discharged into the collector (2) through the gas outlet (12) and collected, and the carbon materials are accumulated on the surface of the catalyst (15).

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