CN112403416A - Device and method for synthesizing ammonia - Google Patents

Device and method for synthesizing ammonia Download PDF

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Publication number
CN112403416A
CN112403416A CN202011312571.0A CN202011312571A CN112403416A CN 112403416 A CN112403416 A CN 112403416A CN 202011312571 A CN202011312571 A CN 202011312571A CN 112403416 A CN112403416 A CN 112403416A
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microwave
dielectric barrier
barrier discharge
gas
hydrogen
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潘杰
刘鹏
魏冬梅
李英杰
邹涵冰
刘瑞
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Shandong Normal University
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Shandong Normal University
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Abstract

The invention relates to the technical field of ammonia synthesis, in particular to a device and a method for synthesizing ammonia, wherein the device comprises: the microwave anti-backflow device comprises a microwave power supply, a microwave anti-backflow device, a three-pin tuner, a microwave coaxial resonant cavity and a dielectric barrier discharge reactor which are connected in sequence; the dielectric barrier discharge reactor is connected with a nanosecond pulse power supply, and a catalyst is filled in the dielectric barrier discharge reactor; and the nitrogen source and the hydrogen source are connected with the gas inlet of the microwave coaxial resonant cavity. Forming atmospheric nitrogen and hydrogen microwave discharge plasma at the opening of the microwave coaxial resonant cavity by using the mixed gas of nitrogen and hydrogen; the generated atmospheric pressure nitrogen and hydrogen microwave discharge plasma and the plasma generated in the dielectric barrier discharge reactor act together, and the synthesis of ammonia is realized under the synergistic action of the catalyst in the dielectric barrier discharge reactor, the separate control of the surface temperature of the gas and the catalyst can be realized, and the conversion efficiency and the yield of the generated ammonia are higher.

Description

Device and method for synthesizing ammonia
Technical Field
The invention relates to the technical field of ammonia synthesis, in particular to a device and a method for synthesizing ammonia.
Background
The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.
Ammonia is a very important chemical substance and an important raw material for industrial and agricultural production. Ammonia also has a high energy density and hydrogen content and is a potential hydrogen storage carrier. The Haber-Bosch process, which is currently used for the industrial large-scale synthesis of ammonia, is energy-consuming and has a negative impact on the environment. Under the conditions of increasingly prominent environmental problems and energy shortage, the exploration of a green, energy-saving and sustainable ammonia synthesis technology is urgent.
The plasma contains a large amount of high-energy electrons, active particles, excited particles and free radicals, can excite, dissociate or ionize nitrogen and hydrogen molecules under the conditions of low temperature and normal pressure, and the plasma synthesis of ammonia takes the nitrogen and the hydrogen as raw material gases and is combined with the conventional catalytic synthesis of ammonia, so that the yield and the energy efficiency of the synthesis of ammonia can be effectively improved, and the method is an effective ammonia synthesis method. However, most of the traditional catalytic ammonia synthesis devices cannot separately control the surface temperature of gas and catalyst, so that the defects of low conversion efficiency, low yield and the like are caused.
Disclosure of Invention
In view of the technical problems in the prior art, the present invention aims to provide an apparatus and a method for synthesizing ammonia, which realize the catalytic synthesis of ammonia by plasma under the conditions of atmospheric pressure and low temperature through the synergistic effect of a microwave discharge reactor, a dielectric barrier discharge reactor and a catalyst.
Specifically, the technical scheme of the invention is as follows:
in a first aspect of the present invention, there is provided an apparatus for synthesizing ammonia, comprising:
the microwave anti-backflow device comprises a microwave power supply, a microwave anti-backflow device, a three-pin tuner, a microwave coaxial resonant cavity and a dielectric barrier discharge reactor which are connected in sequence;
the dielectric barrier discharge reactor is connected with a nanosecond pulse power supply, and a catalyst is filled in the dielectric barrier discharge reactor;
and the nitrogen source and the hydrogen source are connected with the gas inlet of the microwave coaxial resonant cavity.
In a second aspect of the present invention, there is provided a method for synthesizing ammonia, comprising the steps of:
forming atmospheric nitrogen and hydrogen microwave discharge plasma at the opening of the microwave coaxial resonant cavity by using the mixed gas of nitrogen and hydrogen;
the generated atmospheric pressure nitrogen and hydrogen microwave discharge plasma and the plasma generated in the dielectric barrier discharge reactor act together, and the synthesis of ammonia is realized under the synergistic action of the catalyst in the dielectric barrier discharge reactor.
The specific embodiment of the invention has the following beneficial effects:
in the embodiment of the invention, nitrogen and hydrogen mixed gas passes through the inside of the microwave discharge resonant cavity and the inside of the dielectric barrier discharge reactor, and the ammonia is synthesized by plasma catalysis under the condition of atmospheric pressure and low temperature through the synergistic effect of the microwave discharge reactor, the dielectric barrier discharge reactor and the catalyst, so that the separate control of the surface temperature of the gas and the catalyst can be realized, the conversion rate is high, and the yield is high.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.
FIG. 1 is a schematic diagram of an apparatus for synthesizing ammonia according to one or more embodiments of the present invention;
the device comprises a microwave power supply 1, a circulator 2, a water load 3, a three-pin matcher 4, a three-pin matcher 5, a microwave energy inlet 6, a gas inlet 7, a gas outlet 8, a microwave coaxial resonant cavity 9, a dielectric barrier discharge reactor 10, a high-voltage electrode 11, a nanosecond pulse power supply 12, an infrared thermal imager 13, a gas chromatograph 14, a container filled with sulfuric acid solution 15, a Rogowski coil 16, a grounding electrode 17, a tubular furnace 18, an oscilloscope 19, a computer 20, nitrogen, 21, hydrogen, 22, a pressure reducing valve 23, a flowmeter 24, a thermocouple thermometer 25, an air heater 26, a flow equalizer 27 and a catalyst.
Detailed Description
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
In one embodiment of the present invention, there is provided an apparatus for synthesizing ammonia, comprising:
the microwave anti-backflow device comprises a microwave power supply, a microwave anti-backflow device, a three-pin tuner, a microwave coaxial resonant cavity and a dielectric barrier discharge reactor which are connected in sequence;
the dielectric barrier discharge reactor is connected with a nanosecond pulse power supply, and a catalyst is filled in the dielectric barrier discharge reactor;
and the nitrogen source and the hydrogen source are connected with the gas inlet of the microwave coaxial resonant cavity.
The microwave power supply is used for driving microwave discharge; the microwave discharge is a discharge plasma device which uses a waveguide or a transmission line to transmit microwave energy under the excitation of a microwave power supply and forms non-equilibrium discharge plasma in a microwave resonant cavity. Compared with other gas discharge, the microwave discharge has the advantages of uniformity, stability, high energy conversion efficiency, no electrode pollution, high density of charged particles and active particles and the like.
The microwave backflow preventer is used for isolating the reflected wave and preventing the reflected wave from damaging the microwave power supply;
the three-pin tuner is used for carrying out impedance matching on the microwave transmission system;
and the microwave coaxial resonant cavity forms atmospheric pressure nitrogen and hydrogen microwave discharge plasma at the opening of the coaxial resonant cavity.
The dielectric barrier discharge reactor has the advantages of low energy consumption, uniform and stable discharge and simple structure, can form interaction and synergistic effect with a catalyst, and is suitable for plasma catalysis under atmospheric pressure. The packed bed dielectric barrier discharge has high electric field intensity and electron energy, can generate more frequent electron impact ionization, excitation, decomposition and other plasma reactions, generates abundant charged particles, free radicals and excited state particles, and activates plasma catalysis with higher energy efficiency.
The dielectric barrier discharge plasma excited by the nanosecond pulse power supply has the advantages of high field intensity and low temperature, uniform discharge is easy to realize, and the plasma can be effectively adjusted by changing pulse parameters; the catalyst and the dielectric barrier discharge reactor are optimized by combining nanosecond pulse power supply excitation, and the reasonable regulation and control of the gas conversion rate and the energy efficiency of the ammonia synthesis catalyzed by the dielectric barrier discharge plasma can be realized.
In the embodiment of the invention, nitrogen and hydrogen mixed gas passes through the inside of a resonant cavity of microwave discharge and the inside of a dielectric barrier discharge reactor, and the plasma catalytic synthesis of ammonia is realized under the condition of atmospheric pressure and low temperature through the synergistic effect of the microwave discharge reactor, the dielectric barrier discharge reactor and a catalyst.
In some embodiments, the microwave backflow prevention device comprises a circulator and a water load, and an inlet section and an outlet end of the circulator are respectively connected with a microwave power supply and a three-pin dispenser.
The microwave backflow preventer is used to isolate the reflected wave and avoid the reflected wave from damaging the microwave power supply.
The circulator is a device for unidirectional annular transmission of electromagnetic waves, and is a three-port device, the lower end of the circulator is connected with a water load through a flange, and the water load can adjust the water temperature through a cold water circulating pump.
The water load is a common high-power microwave matching load, can be divided into an absorption water load and a radiation water load according to the working mode, and both use flowing water as an absorber of microwaves. The water load can play the roles of backflow prevention and temperature reduction at the same time.
In some embodiments, the length of the microwave coaxial resonant cavity is generally set to an odd number of quarter wavelengths, the gas inlet end of the microwave coaxial resonant cavity is closed, the gas outlet end is open, that is, an opening is formed, the enhanced electric field can easily ionize the gas, and a plasma jet is formed at the opening of the gas outlet end.
In some embodiments, the dielectric barrier discharge reactor has a plate-plate electrode structure, and high voltage electrodes, namely a high voltage electrode and a low voltage electrode, are arranged on the upper inner side and the lower inner side of the dielectric barrier discharge reactor; the upper high-voltage electrode is connected with a nanosecond pulse power supply, and the lower high-voltage electrode is connected with a grounding electrode;
in some embodiments, the nitrogen source is a nitrogen cylinder and the hydrogen source is a hydrogen cylinder; the outlet pipelines of the nitrogen gas bottle and the hydrogen gas bottle are respectively provided with a pressure reducing valve 22, and the downstream of the pressure reducing valve is respectively provided with a flowmeter 23;
the nitrogen gas cylinder is filled with high-purity nitrogen gas, and the hydrogen gas cylinder is filled with high-purity hydrogen gas. The nitrogen and the hydrogen are respectively regulated in gas pressure and flow by a pressure reducing valve and a flow meter, and mixed gas of nitrogen and hydrogen is formed after premixing and enters the microwave coaxial resonant cavity.
In some embodiments, an air heater 25 and a current equalizer 26 are further disposed between the nitrogen source and the hydrogen source and the gas inlet of the microwave coaxial resonant cavity, the nitrogen source and the hydrogen source are connected to the air heater 25, and the air heater 25 is connected to the current equalizer 26 and the gas inlet of the microwave coaxial resonant cavity 8 in turn;
the air heater can change the temperature of the gas, and the nitrogen and the hydrogen are heated to a proper temperature according to the requirement of the ammonia synthesis by plasma catalysis, so that the efficiency of the ammonia synthesis by plasma catalysis is improved; the purpose of the flow equalizer is to mix nitrogen and hydrogen evenly.
In some embodiments, a thermocouple thermometer 24 is disposed in the air heater 25;
the thermocouple thermometer is a temperature measuring instrument based on a thermoelectric effect, detects a gas temperature using the thermocouple thermometer, and transmits the detected information to a computer to observe an appropriate gas temperature, and performs gas temperature adjustment by an air heater.
In some embodiments, the apparatus for synthesizing ammonia further comprises a thermal infrared imager 12, a gas chromatograph 13 and a vessel 14 containing sulfuric acid; the thermal infrared imager 12 is connected to a gas outlet of the dielectric barrier discharge reactor 9, and the thermal infrared imager 12 is sequentially connected with a gas chromatograph 13 and a container 14 filled with sulfuric acid;
the thermal infrared imager is used for acquiring temperature information of the surface of the catalyst in real time; the product obtained after ammonia is catalytically synthesized by the nitrogen and hydrogen plasmas enters a gas chromatograph, and the gas chromatograph detects the property of the product and transmits the detected result and data to a computer; a vessel containing a sulfuric acid solution was used to absorb the ammonia gas produced.
In some embodiments, the apparatus for synthesizing ammonia further comprises a rogowski coil 15, an oscilloscope 18 and a computer 19, wherein the rogowski coil 15 is positioned between the dielectric barrier discharge reactor 9 and the grounding electrode 16, the rogowski coil 16 is connected with the oscilloscope 18, one end of the oscilloscope 18 is connected with the gas chromatograph 13, and the other end of the oscilloscope 18 is connected with the computer 17;
the Rogowski coil is used for detecting a current signal, and the oscilloscope is used for displaying a current wave pattern.
The rogowski coil is also called a differential current sensor, and is a ring-shaped coil uniformly wound on a non-ferromagnetic material. The output signal is the current differential over time; the input current can be truly restored by a circuit which integrates the output voltage signal. An oscilloscope is an instrument used to measure the shape of an alternating current or pulsed current wave.
And (4) analyzing and processing the result and the data obtained by the detection of the gas chromatograph by the computer, and calculating to obtain the gas conversion rate.
In some embodiments, the dielectric barrier discharge reactor 9 is located within a tube furnace 17;
the tubular furnace is mainly used for heating the catalyst, the dielectric barrier discharge reactor filled with the catalyst is placed into the tubular furnace, and the temperature control of the surface of the catalyst is realized by arranging the tubular furnace for heating.
In one embodiment of the present invention, there is provided a method for synthesizing ammonia, comprising the steps of:
forming atmospheric nitrogen and hydrogen microwave discharge plasma at the opening of the microwave coaxial resonant cavity by using the mixed gas of nitrogen and hydrogen;
the generated atmospheric pressure nitrogen and hydrogen microwave discharge plasma and the plasma generated in the dielectric barrier discharge reactor act together, and the synthesis of ammonia is realized under the synergistic action of the catalyst in the dielectric barrier discharge reactor.
In some embodiments, the microwave power supply is a 2.45GHz microwave power supply;
in some embodiments, the catalyst is magnesium chloride, preferably, the catalyst is a spherical magnesium chloride catalyst;
magnesium chloride is introduced into the plasma for catalyzing and synthesizing ammonia as a catalyst which can reduce the activation energy of nitrogen and hydrogen and an absorbent which can absorb ammonia in situ. When magnesium chloride is used as the absorbent, a critical absorption intermediate compound Mg can be formed under plasma conditions3N2And Mg (NH)3)6Cl2Absorbing ammonia in situ; after the synthesis of ammonia is finished, the catalyst in the reactor is taken out, the catalyst is placed into water and dissolved to generate ammonia gas, the catalyst is taken out of the water and dried, and then the catalyst is placed into the reactor again, so that the catalyst can be recycled, and the efficiency of synthesizing ammonia by plasma catalysis is improved.
In some embodiments, the dielectric barrier discharge reactor is energized by a nanosecond pulsed power supply having a frequency of 0-15KHz, an output amplitude of 0-15KV, a pulse rise time and a pulse fall time of 50-500ns, to ionize gas inside the dielectric barrier discharge reactor to produce a discharge plasma.
In some embodiments, the surface temperature of the catalyst is 700K;
in some embodiments, the gas temperature is about 250 ℃;
in some embodiments, the flow rate of the gas is 90 mL/min.
In order to avoid the heat transfer phenomenon, the gas is enabled to rapidly pass through the discharge plasma reactor by increasing the flow velocity of the gas, so that the temperature of the surface of the gas and the temperature of the catalyst are separately controlled.
Example 1
As shown in fig. 1, an apparatus for synthesizing ammonia comprises:
the microwave anti-backflow device comprises a microwave power supply 1, a microwave anti-backflow device, a three-pin tuner 4, a microwave coaxial resonant cavity 8 and a dielectric barrier discharge reactor 9 which are connected in sequence;
the dielectric barrier discharge reactor 9 is connected with the nanosecond pulse power supply 11, and a catalyst 27 is filled in the dielectric barrier discharge reactor 9; the dielectric barrier discharge reactor 9 is positioned in the tube furnace 17;
the upper inner side and the lower inner side of the dielectric barrier discharge reactor 9 are provided with high voltage electrodes 10, the high voltage electrodes comprise an upper high voltage electrode and a lower high voltage electrode, and the catalyst 27 is filled in the high voltage electrodes; the upper high-voltage electrode is connected with the nanosecond pulse power supply 11, and the lower high-voltage electrode is connected with the grounding electrode 16;
the nitrogen source is a nitrogen gas cylinder, and the hydrogen source is a hydrogen gas cylinder; the outlet pipelines of the nitrogen gas bottle and the hydrogen gas bottle are respectively provided with a pressure reducing valve 22, and the downstream of the pressure reducing valve is respectively provided with a flowmeter 23;
an air heater 25 and a flow equalizer 26 are also arranged between the nitrogen gas cylinder and the hydrogen gas cylinder and the gas inlet of the microwave coaxial resonant cavity 8, the nitrogen gas cylinder and the hydrogen gas cylinder are respectively connected with the air heater 25 through pipelines, and the air heater 25 is sequentially connected with the flow equalizer 26 and the gas inlet of the microwave coaxial resonant cavity 8; a thermocouple thermometer 24 is arranged in the air heater 25;
the device for synthesizing ammonia further comprises a thermal infrared imager 12, a gas chromatograph 13 and a container 14 filled with sulfuric acid; the thermal infrared imager 12 is connected to a gas outlet of the dielectric barrier discharge reactor 9, and the thermal infrared imager 12 is sequentially connected with a gas chromatograph 13 and a container 14 filled with sulfuric acid;
the device for synthesizing ammonia further comprises a Rogowski coil, an oscilloscope and a computer, wherein the Rogowski coil is positioned between the dielectric barrier discharge reactor and the grounding electrode, the Rogowski coil is connected with the oscilloscope, one end of the oscilloscope is connected with the gas chromatograph, and the other end of the oscilloscope is connected with the computer.
Example 2
A method for synthesizing ammonia, comprising the steps of:
nitrogen and hydrogen in a volume ratio of 2: 1, heating the mixed gas to 250 ℃, equalizing the flow of the mixed gas, then feeding the heated mixed gas into a microwave coaxial resonant cavity, forming atmospheric-pressure nitrogen and hydrogen microwave discharge plasma at an opening of the microwave coaxial resonant cavity, feeding the sprayed microwave discharge plasma into a dielectric barrier discharge reactor, enabling the microwave discharge plasma and the plasma generated in the dielectric barrier discharge reactor to act together, and realizing the synthesis of ammonia under the action of a catalyst in the dielectric barrier discharge reactor;
the dielectric barrier discharge reactor is excited by a nanosecond pulse power supply, the frequency is 3KHz, the output amplitude is 14KV, and the pulse rising time and the pulse falling time are 100 ns; the catalyst in the dielectric barrier discharge reactor is a spherical magnesium chloride catalyst, the surface temperature of the catalyst is 700K, and the flow rate of the mixed gas is 90 mL/min.
NH detected at the gas outlet of the ammonia synthesis plant3The concentration reaches 17500 ppm.
Example 3
A method for synthesizing ammonia, comprising the steps of:
nitrogen and hydrogen in a volume ratio of 2: 1, heating the mixed gas to 250 ℃, equalizing the flow of the mixed gas, then feeding the heated mixed gas into a microwave coaxial resonant cavity, forming atmospheric-pressure nitrogen and hydrogen microwave discharge plasma at an opening of the microwave coaxial resonant cavity, feeding the sprayed microwave discharge plasma into a dielectric barrier discharge reactor, enabling the microwave discharge plasma and the plasma generated in the dielectric barrier discharge reactor to act together, and realizing the synthesis of ammonia under the action of a catalyst in the dielectric barrier discharge reactor;
the dielectric barrier discharge reactor is excited by a nanosecond pulse power supply, the frequency is 5KHz, the output amplitude is 10KV, and the pulse rising time and the pulse falling time are 150 ns;
the catalyst in the dielectric barrier discharge reactor is a spherical magnesium chloride catalyst, the surface temperature of the catalyst is 700K, and the flow rate of the mixed gas is 90 mL/min.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. An apparatus for synthesizing ammonia, comprising:
the microwave anti-backflow device comprises a microwave power supply, a microwave anti-backflow device, a three-pin tuner, a microwave coaxial resonant cavity and a dielectric barrier discharge reactor which are connected in sequence;
the dielectric barrier discharge reactor is connected with a nanosecond pulse power supply, and a catalyst is filled in the dielectric barrier discharge reactor;
and the nitrogen source and the hydrogen source are connected with the gas inlet of the microwave coaxial resonant cavity.
2. An apparatus for synthesizing ammonia according to claim 1, wherein said microwave backflow preventer comprises a circulator and a water load, an inlet section and an outlet end of the circulator being connected to a microwave power supply and a three-pin dispenser, respectively;
or the length of the microwave coaxial resonant cavity is set to be an odd number of quarter wavelengths.
3. An apparatus for synthesizing ammonia as claimed in claim 1, wherein said dielectric barrier discharge reactor is a plate-plate electrode structure, high voltage electrodes are disposed on the upper and lower inner sides of the dielectric barrier discharge reactor, and the high voltage electrodes include an upper high voltage electrode and a lower high voltage electrode; the upper high-voltage electrode is connected with a nanosecond pulse power supply, and the lower high-voltage electrode is connected with a grounding electrode;
preferably, the dielectric barrier discharge reactor is arranged in a tube furnace.
4. An apparatus for synthesizing ammonia according to claim 1, wherein said nitrogen source is a nitrogen gas cylinder and said hydrogen source is a hydrogen gas cylinder; and outlet pipelines of the nitrogen gas cylinder and the hydrogen gas cylinder are respectively provided with a pressure reducing valve, and the downstream of the pressure reducing valve is respectively provided with a flowmeter.
5. An apparatus for synthesizing ammonia as claimed in claim 1, wherein an air heater and a current equalizer are further provided between the nitrogen source and the hydrogen source and the gas inlet of the microwave coaxial resonant cavity, the nitrogen source and the hydrogen source are connected to the air heater, and the air heater is connected to the current equalizer and the gas inlet of the microwave coaxial resonant cavity in turn;
preferably, a thermocouple thermometer is arranged in the air heater.
6. An apparatus for synthesizing ammonia as claimed in claim 1, wherein said apparatus for synthesizing ammonia further comprises a thermal infrared imager, a gas chromatograph and a vessel containing sulfuric acid;
the thermal infrared imager is connected to a gas outlet of the dielectric barrier discharge reactor, and the thermal infrared imager is sequentially connected with a gas chromatograph and a container filled with sulfuric acid.
7. An apparatus for synthesizing ammonia according to claim 1, wherein said apparatus for synthesizing ammonia further comprises a rogowski coil, an oscilloscope and a computer;
the Rogowski coil is positioned between the dielectric barrier discharge reactor and the grounding electrode, the Rogowski coil is connected with an oscilloscope, one end of the oscilloscope is connected with the gas chromatograph, and the other end of the oscilloscope is connected with the computer.
8. A method for synthesizing ammonia, comprising the steps of:
forming atmospheric nitrogen and hydrogen microwave discharge plasma at the opening of the microwave coaxial resonant cavity by using the mixed gas of nitrogen and hydrogen;
the generated atmospheric pressure nitrogen and hydrogen microwave discharge plasma and the plasma generated in the dielectric barrier discharge reactor act together, and the synthesis of ammonia is realized under the synergistic action of the catalyst in the dielectric barrier discharge reactor.
9. A method for synthesizing ammonia according to claim 8,
the microwave power supply is a 2.45GHz microwave power supply;
or the frequency of the nanosecond pulse power supply is 0-15KHz, the output amplitude is 0-15KV, and the pulse rising time and the pulse falling time are 50-500 ns.
10. A method for synthesizing ammonia according to claim 8,
the catalyst is magnesium chloride, and preferably, the catalyst is a spherical magnesium chloride catalyst;
alternatively, the surface temperature of the catalyst is 700 deg.C,
or the gas temperature is 200 DEG C
Alternatively, the flow rate of the gas is 90 mL/min.
CN202011312571.0A 2020-11-20 2020-11-20 Device and method for synthesizing ammonia Pending CN112403416A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113522020A (en) * 2021-08-25 2021-10-22 江南大学 A DBD plasma processing system for heterogeneous catalysis of normal atmospheric temperature
CN114205986A (en) * 2021-12-13 2022-03-18 合肥综合性国家科学中心能源研究院(安徽省能源实验室) Magnetically enhanced microwave plasma nitrogen fixation method and device
EP4258321A1 (en) * 2022-04-07 2023-10-11 Karlsruher Institut für Technologie Methods and systems for synthesis of chemical energy carriers using intermittent energy sources

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113522020A (en) * 2021-08-25 2021-10-22 江南大学 A DBD plasma processing system for heterogeneous catalysis of normal atmospheric temperature
CN114205986A (en) * 2021-12-13 2022-03-18 合肥综合性国家科学中心能源研究院(安徽省能源实验室) Magnetically enhanced microwave plasma nitrogen fixation method and device
EP4258321A1 (en) * 2022-04-07 2023-10-11 Karlsruher Institut für Technologie Methods and systems for synthesis of chemical energy carriers using intermittent energy sources

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