KR102128228B1 - Method for ammonia synthesis using lithium super ionic conductor - Google Patents

Abstract

The present invention relates to a method for synthesizing ammonia based on a lithium superion conductor, and the synthesis method can synthesize ammonia with high yield by optimizing the ammonia synthesis conditions required for each step.

Description

Method for ammonia synthesis using lithium super ionic conductor

The present invention relates to ammonia synthesis, and to a method for synthesizing ammonia based on lithium superion conductors.

Ammonia is a hydrogen and nitrogen compound with the chemical formula NH ₃ and exists in a gaseous state with an irritating odor at room temperature. A small amount is contained in the atmosphere, and it is contained in a trace amount in natural water, and may be generated and present in the process of decomposing nitrogen organic matter of bacteria in the soil.

Ammonia is used as a raw material for various chemical industries, for the production of ammonia water, and as a solvent for ionic substances. In addition, the frequency of use of new and renewable energy is increasing to prepare for the depletion of petroleum resources and to achieve greenhouse reduction targets in response to climate change. Renewable energy has the problem of local ubiquity and intermittence, so the means of storage and transportation are essential. Ammonia and hydrogen are attracting attention as energy carriers for solving these problems. Hydrogen has limitations in storage and transport, but ammonia is in a liquid state at a normal temperature of 8.5 atmospheres, so it is easier to store and transport than hydrogen.

The most common method of producing ammonia is a Haber-Bosch process synthesized from hydrogen and nitrogen. In the presence of an iron or ruthenium catalyst, one nitrogen molecule and three hydrogen molecules are combined to form two ammonia molecules as shown in Formula 1 below. It is a fever process that generates. However, although it is a large-scale industrial process, the yield of ammonia is as low as 10-20%, and there are disadvantages that require additional energy and hydrogen.

Formula 1

N ₂ + 3H ₂ -> 2NH ₃ + 100kJ

In order to overcome the limitations of the Haber-Bosch process, an electrochemical ammonia synthesis method using an ion-conducting oxide electrolyte has been proposed, and an electrochemical ammonia synthesis method using an electrolyte using water and nitrogen as a raw material has been actively studied (Marnellos et al. ). In the electrochemical ammonia synthesis method, an electrolytic cell based on a water-based electrolyte undergoes a series of processes as in the following formula (2), where water is decomposed at the anode and divided into hydrogen ions and electrons (2-1) and hydrogen It includes reaction (2-2) in which ions and electrons reduce nitrogen molecules to produce ammonia. Since the final products of the ammonia electrochemical synthesis method are only ammonia and oxygen, there is an advantage that there is no carbon emission at all.

Formula 2

Oxide electrode ^{_{reaction: 3H 2 O → 6H + +}} 3 / 2O 2 + 6e - (2-1)

Reduction electrode ^{_{reaction: N 2 + 6H + + 6e}} - → 2NH 3 (2-2)

The main limiting reaction in the electrochemical ammonia synthesis reaction is a step of reducing the nitrogen molecule, which is a reaction on the cathode, to ammonia, which is due to the strong triple bond of the nitrogen molecule. In the case of using an aqueous-based electrolyte, the cathode reaction often occurs in the hydrogen generation reaction instead of the nitrogen reduction reaction. In fact, it is known that the current efficiency is less than 1% when using a water-based system (R. Lan et al.).

U.S. Patent No. 7811442 and European Patent No. 972855 disclose an ammonia synthesis device using a proton conductive solid oxide as an electrolyte and synthesizing ammonia by applying an external current. However, the above patents require a high temperature operating condition by using a solid oxide electrolyte, which is difficult to obtain a high yield since ammonia is a temperature that can be decomposed into hydrogen and nitrogen gas.

U.S. Patent No. 8916123 discloses a method for synthesizing ammonia using an ammonia synthesis cell partitioned into a positive electrode and a negative electrode by a lithium ion conductor. However, this has a problem of low ammonia synthesis yield due to side reaction of lithium and solvent or corrosion of lithium conductor by lithium.

Therefore, there is a need for an energy-friendly ammonia synthesis device with higher yield and lower manufacturing cost.

The present invention has been devised to solve the above-described conventional problems, and is to provide a method for synthesizing ammonia based on lithium superion conductor capable of obtaining a high ammonia synthesis yield.

The present inventors have completed the present invention by discovering that ammonia can be synthesized with a high yield by optimizing the ammonia synthesis conditions required for each step by a method for synthesizing ammonia based on a lithium superion conductor.

The present invention is a method for synthesizing ammonia based on a lithium superion conductor, wherein the method uses lithium electrolytic cells on one side of the reduction electrode using an electrochemical cell in which the anode section and the cathode section are partitioned by a lithium superion conductor. Manufacturing a thin metal plate; Washing the lithium thin film metal plate; producing a lithium nitride thin film metal plate to form lithium nitride (Li ₃ N) on the lithium thin film by heating the lithium thin film metal plate which has undergone the washing step in a nitrogen atmosphere reactor; And synthesizing ammonia by supporting the lithium nitride thin film metal plate in an acid solution, wherein the anode part includes an anode electrode and an anode solution, and the cathode part includes a cathode electrode and a cathode solution, The anode solution is an aqueous solution of Li ₂ SO ₄ , lithium ions passed by a lithium superion conductor are coated on a cathode, and the cathode solution contains a lithium salt, an organic solvent, and an additive, and is based on a lithium superion conductor based on ammonia. Synthetic methods are provided.

The present invention is also a method for synthesizing ammonia using a lithium-ion conductor-based compartmentalized ammonia synthesis device, wherein the method has a rotating cathode as a central axis, and a first compartment, a second compartment, and A cylindrical reaction device divided into a third compartment, the method comprising: positioning an oxide electrode and a superionic conductor so as to face a cathode in an electrolyte containing an additive in the first compartment and depositing a lithium thin film on the cathode; Forming a lithium nitride thin film by rotating the portion where the lithium thin film is formed into a second compartment and supplying nitrogen gas and heating it; And synthesizing ammonia by rotating the portion where the lithium nitride thin film is formed into a third compartment and making contact with an acid solution, wherein the electrolyte is Li ₂ SO _4. And a lithium salt, wherein Li ₂ SO ₄ produced in the step of synthesizing ammonia is supplied to a first compartment for reuse, and the third compartment comprises an ammonium selective membrane, a method for synthesizing ammonia based on lithium superion conductors. Gives

In addition, the present invention, the oxide electrode is Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Os, Ir, Pt, and one or more alloys selected from the group consisting of Au, and the cathode is at least one selected from the group consisting of Ti, Mo, Fe, Co, Ni, Cu, Ag and Zn Provided is a method for synthesizing ammonia based on an alloy, lithium superion conductor.

The present invention also, the lithium salt is lithium perchlorate, lithium dithionite, lithium sulfate, lithium tetrafluoroborate, lithium hexafluorophosphate, lithium bromide and lithium chloride, lithium bistrifluoromethanesulfonyl imide ( LiTFSI), lithium bisfluoromethanesulfonyl imide (LiFSI), lithium bis-oxalatoborate (LiBOB), one or more selected from the group consisting of a lithium super-ion conductor-based ammonia synthesis method.

In addition, the present invention, the organic solvent is propylene carbonate, ethylene carbonate, dimethyl carbonate, 1,3-dioxolane (1,3-dioxolane, DOL), a group consisting of a solvent containing dimethoxyethane (dimethoxyethane, DME) It provides a method for synthesizing ammonia based on lithium superion conductors, which is one or more selected from.

In addition, the present invention, the additive is sodium, potassium, cesium, rubidium, magnesium, potassium, strontium, fluoroethylene carbonate (fluoroethylene carbonate, including FEC) one or more additives selected from the group consisting of, based on lithium superionic conductors A method for synthesizing ammonia is provided.

The present invention also provides a method for synthesizing ammonia based on lithium superion conductor, wherein the washing is performed using 2-methyl tetrahydrofuran.

The present invention also provides a method for synthesizing ammonia based on lithium superion conductors, wherein the heating is performed at 200°C to 230°C for 30 minutes to 1 hour.

The present invention also provides a method for synthesizing ammonia based on lithium superion conductor, wherein the acid solution is H ₂ SO ₄ .

The present invention also provides a method for synthesizing ammonia based on lithium superion conductors, wherein the metal plate that has undergone the step of synthesizing ammonia is reused as a cathode.

The present invention also provides a method for synthesizing ammonia based on lithium superion conductors, wherein the electrodeposition is performed for 5 to 20 minutes.

The present invention also, the step of synthesizing the ammonia further includes the step of temporarily adjusting the pH to 10 or more to convert the ammonium into an ammonia gas state, wherein the ammonium selective film is polypropylene (polypropylene, PP), polyvinyl It provides a method for synthesizing ammonia based on lithium superion conductor, a gas permeable membrane selected from the group consisting of polyvinilidenefluoride (PVDF) and polytetrafluoroethylene (PTFE).

The method for synthesizing ammonia based on the lithium superion conductor of the present invention can synthesize ammonia with high yield by optimizing the ammonia synthesis conditions required for each step.

1 is a schematic diagram showing a method for synthesizing ammonia based on a superionic conductor according to an embodiment of the present invention.
Figure 2 is a graph showing the ammonia synthesis rate according to the temperature and whether to wash the lithium thin metal plate according to an embodiment of the present invention.
3 is a graph showing the ammonia synthesis yield according to the temperature and whether to wash the lithium thin metal plate according to an embodiment of the present invention.
4 is a graph showing the yield of ammonia synthesis over time according to one embodiment of the present invention.
5 is a schematic view showing a continuous ammonia synthesis reactor according to an embodiment of the present invention.
6 is a graph comparing the amount of ammonia synthesis according to the presence or absence of an additive in one embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings, so that those of ordinary skill in the art can easily implement them. Prior to the detailed description of the present invention, terms or words used in the present specification and claims described below should not be construed as being limited to a conventional or dictionary meaning. Therefore, the embodiments shown in the embodiments and drawings described in this specification are only the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention, and thus can replace them at the time of application. It should be understood that there may be equivalents and variations.

In one aspect, the present invention is a method for synthesizing ammonia based on a lithium superion conductor, wherein the method uses an electrochemical cell in which an anode part and a cathode part are partitioned by a lithium superion conductor to electrodeposit lithium on one side of the cathode (electrodeposition). ) To produce a lithium thin film metal plate; Washing the lithium thin film metal plate; A lithium nitride thin film metal plate production step of heating the lithium thin film metal plate which has undergone the washing step in a nitrogen atmosphere reactor to form lithium nitride (Li ₃ N) on the lithium thin film; And synthesizing ammonia by supporting the lithium nitride thin film metal plate in an acid solution.

Lithium super ionic conductor (Lithium super ionic conductor, LISICON) can be represented by the formula Li _2+2x Zn _1-x GeO ₄ , for example Li _{3 . 5} Zn _{0 . 25} GeO ₄ , solid and lithium ion conductive material. In the present invention, a lithium thin metal plate required for ammonia synthesis is manufactured by using an electrochemical cell in which a cathode portion and a cathode portion are partitioned by a lithium superion conductor. 1 is a schematic diagram showing a method for synthesizing ammonia of the present invention, and FIG. 1(a) shows an electrochemical cell 1 using a lithium superion conductor 10. The electrochemical cell 1 partitioned by a lithium super-ion conductor is divided into an anode part 11 and a cathode part 12, and the anode part 11 includes an anode electrode 100 and an anode solution 110, The cathode portion includes a cathode electrode 200 and a cathode electrode 210. When voltage is applied to the anode electrode 100 and the cathode electrode 200, water is oxidized in the anode electrode 100 as shown in Reaction Formula 1, and electrons are generated, and the electrons move to the cathode electrode 200 so that lithium superion conductor ( 10) The lithium ions passed through are reduced on the surface of the cathode 200. Lithium ions are electrodeposited with lithium metal on the surface of the cathode, thereby obtaining a lithium thin film metal plate 201 which is a lithium electrode electrodeposited. The electrodeposition can be performed for 5 to 20 minutes.

Scheme 1

Reduction electrode: 6Li ^{+ +} 6e ^- → 6Li

Oxide electrode: 3H ₂ O ^{_{→ 3 / 2O 2 + 6H +}} + 6e -

In one embodiment, the oxide electrode is Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W , Re, Os, Ir, Pt, and one or more alloys selected from the group consisting of Au, and the cathode is preferably a metal material that does not cause a side reaction with Li, Ti, Mo, Fe, Co, Ni, Cu, Ag and Zn are one or more alloys selected from the group consisting of. It is preferable to use an aqueous solution of Li ₂ SO _{4 as the} anode solution, and the cathode solution is a salt capable of delivering lithium ions, for example, lithium perchlorate, lithium dithionite, lithium sulfate, lithium tetrafluoroborate, lithium hexa Solutions containing fluorophosphate, lithium bromide and lithium chloride, lithium bistrifluoromethanesulfonylimide (LiTFSI), lithium bisfluoromethanesulfonylimide (LiFSI), lithium bisoxalateborate (LiBOB) Can be used. As the electrolyte solvent, a solvent containing propylene carbonate, ethylene carbonate, dimethyl carbonate, 1,3-dioxolane (DOL), dimethoxyethane (DME) may be used. Preferably, a mixed solution of 1,3-dioxolane and dimethoxyethane containing lithium bisfluoromethanesulfonyl imide can be used. In addition, one or more additives selected from the group consisting of sodium, potassium, cesium, rubidium, magnesium, potassium, strontium, and fluoroethylene carbonate (FEC) may be used in the cathode solution. The additive can suppress side reactions and improve ammonia yield.

FIG. 1(b) shows that the lithium thin metal plate 201 manufactured in the electrochemical cell using the lithium superion conductor is washed in the washing solution 300. The lithium thin metal plate 201 may be washed by washing a side reaction product or the like formed when the lithium thin film is formed, thereby increasing the ammonia synthesis yield. In one embodiment, the washing solution is 2-methyl tetrahydrofuran, simple immersed washing for 30 seconds to 120 seconds, and dried for 1 minute or more in an argon atmosphere. The dried lithium thin film metal plate 201 is heated in a nitrogen atmosphere reactor as shown in FIG. 1(c) to form lithium nitride on the surface of the lithium thin film as shown in Reaction Scheme 2, thereby preparing a lithium nitride thin film metal plate 202. In one embodiment, the heating is performed at 200°C to 230°C for 30 minutes to 1 hour. When performed at 200°C or lower, lithium nitride is not sufficiently generated, and when it is 230°C or higher, side reactions may occur or uniform lithium nitride formation may be difficult.

Scheme 2

6Li + N ₂ → 2Li ₃ N

The lithium nitride thin film metal plate 202 synthesizes ammonia as shown in FIG. 1(d). When lithium nitride is in contact with an acid solution, ammonia is synthesized as shown in Scheme 3.

Scheme 3

2Li ₃ N + 6H ⁺ → 2NH ₃ + 6Li ⁺

The acid solution is HCl, H ₂ SO ₄ , HNO ₃ , H ₃ PO ₄ , H ₂ CO ₃ may be used, but it is preferable to use H ₂ SO ₄ to reuse the used solution as the anode solution 110 in the electrochemical cell 1 in the step of preparing the lithium thin metal plate described above. The metal plate that has undergone the ammonia synthesis process can also be reused in a manufacturing step of a lithium nitride thin film metal plate by washing or washing with a cathode in an electrochemical cell. The synthesized ammonia can be collected using any of the ammonia capture processes known to those skilled in the art. In one embodiment of the present invention, ammonia is collected by using water to obtain ammonia water.

In another aspect, the present invention is a method for synthesizing ammonia using a compartmentalized ammonia synthesis device based on lithium superion conductor shown in FIG. 5. The method has a rotating cathode as a central axis, and a cylindrical reaction device divided into a first compartment, a second compartment, and a third compartment based on the cathode may be used. In the above device, a reaction occurs in each compartment by rotating the cathode, and the compartment membrane is a membrane through which a substance present in each compartment cannot penetrate. The method using the compartment type ammonia synthesis device comprises the steps of positioning the anode and superionic conductor in the electrolyte containing the additive in the first compartment so as to face the cathode and depositing a lithium thin film on the cathode; Forming a lithium nitride thin film by rotating the portion where the lithium thin film is formed into a second compartment and supplying nitrogen gas and heating it; And synthesizing ammonia by rotating the portion where the lithium nitride thin film is formed into a third compartment and making contact with an acid solution. The first compartment is Li ₂ SO ₄ in one embodiment Alternatively, LiOH may be used as the electrolyte, and preferably Li ₂ SO ₄ . The reaction as shown in Reaction Scheme 1 occurs as a compartment for forming a lithium thin film on the surface where the rotary cathode is exposed to the first compartment. In one embodiment, the electrolyte includes one or more additives selected from the group consisting of sodium, potassium, cesium, rubidium, magnesium, potassium, strontium, and fluoroethylene carbonate (FEC). The additive can suppress side reactions and improve ammonia yield.

Li ₂ SO ₄ in the first compartment When a lithium thin film is formed on the cathode in the electrolyte, the cathode is rotated so that the portion where the lithium foil is formed is directed to the second compartment. In the second compartment, nitrogen gas is supplied and heat is applied to form a lithium nitride thin film. In one embodiment, the lithium nitride thin film is formed by heating at 200°C to 230°C for 30 minutes to 1 hour. The cathode in which the lithium nitride thin film is formed synthesizes ammonia by rotating the lithium nitride thin film portion into a third compartment. In the third compartment, the lithium nitride thin film reacts with an acid, and the reaction as shown in Reaction Formula 3 occurs to produce ammonia. The generated Li ₂ SO ₄ can be reused by supplying it to the first zone, and in one embodiment, the third compartment temporarily adjusts the pH to 9.3 to separate Li ₂ SO ₄ and (NH ₄ ) ₂ SO ₄ . Preferably, after adjusting to 10 or more to convert ammonium to an ammonia gas state, ammonia can be separated using an organic or hydrophobic gas permeable membrane. In one embodiment, the gas permeable membrane is polypropylene (PP), poly It is one selected from the group consisting of polyvinilidenefluoride (PVDF) and polytetrafluoroethylene (PTFE).

All technical terms used in the present invention, unless defined otherwise, are used in the sense as commonly understood by those skilled in the art in the relevant field of the present invention. The contents of all publications described by reference herein are incorporated into the present invention.

Hereinafter, examples are provided to help understanding of the present invention. However, the following examples are provided only for easier understanding of the present invention, and the present invention is not limited to the following examples.

Example 1. Synthesis of ammonia based on lithium super-ion conductor

For the synthesis of ammonia based on lithium superion conductor of the present invention, ammonia was synthesized in the same order as in FIG. 1. Pt/C was used as the anode and Ni was used as the cathode in the electrochemical cell partitioned by a lithium super-ion conductor, and 1 M of Li ₂ SO ₄ was used as the anode. 7 ml, 1 M LiClO ₄ as a cathode solution 7 ml of propylene carbonate solution was used. A lithium thin film metal plate was prepared by electrodepositing lithium on a nickel electrode for 400 to 600 seconds at a normal temperature of 6 mA applied current. The prepared lithium thin-film metal plate was immersed in 2-methyltetrahydrofuran (2Me-THF) for 30 seconds to wash, followed by a washing step of drying in an argon atmosphere for 1 minute. A lithium nitride thin film metal plate manufacturing step of heating the washed and dried lithium thin metal plate in a nitrogen atmosphere having a nitrogen flow rate of 1000 sccm was performed, and various temperature conditions and times were performed to determine ammonia synthesis efficiency according to temperature and time, respectively. Ammonia was synthesized by simply immersing the resulting lithium nitride thin film metal plate in a 50 mM sulfuric acid solution at room temperature to terminate the ammonia synthesis reaction immediately after immersion.

The results of ammonia synthesis efficiency are shown in FIGS. 2 to 4 and 6. Lithium nitride thin films were respectively formed on the lithium thin film metal plate at 20°C, 100°C, 180°C, 200°C, 220°C and 240°C for 30 minutes to measure the ammonia synthesis efficiency according to the lithium nitride generation temperature and the presence or absence of washing. Figure 2 is a lithium nitride thin film metal plate manufacturing step in accordance with the temperature conditions and the presence or absence of washing divided by the electrode area and the reaction time (lithium nitride production time) The ammonia synthesis rate is shown, and FIG. 3 shows the Faraday efficiency. 2 and 3, it can be seen that when ammonia is synthesized by a lithium nitride thin film metal plate that has undergone a washing step, it exhibits high ammonia production and Faraday efficiency at most temperature conditions. If the washing step is not performed, it is determined that the formation of the lithium nitride thin film is impaired due to the residue of propylene carbonate contained in the cathode solution. Propylene carbonate has a low vapor pressure, making it difficult to completely dry and remove it. Due to its high reactivity with lithium, side reactions occur when forming a lithium nitride thin film at high temperatures, making it difficult to form a lithium nitride thin film. However, when the lithium thin metal plate is washed with 2Me-THF and a lithium nitride thin film is formed, the reactivity with lithium is very low and the vapor pressure is large, so most of it can be removed simply by drying argon. Therefore, forming lithium nitride on the lithium thin film metal plate which has undergone the washing step may exhibit high ammonia efficiency. The ammonia synthesis efficiency according to the formation temperature of the lithium nitride thin film was the highest at 220°C, and at a temperature above that, the side reaction proceeds and the ammonia synthesis efficiency is judged to be lowered.

4 is a measurement of the ammonia synthesis Faraday efficiency according to the formation time of the lithium nitride thin film. A lithium nitride thin film was formed on the washed lithium thin film metal plate for 10 to 120 minutes, and was simply immersed in sulfuric acid. As a result, the ammonia produced from the metal plate formed with lithium nitride for the first 10 minutes and 20 minutes shows a rapid difference in efficiency, and the metal plate formed with lithium nitride in more than 20 minutes shows the ammonia synthesis efficiency in a slow form, resulting in a logarithmic graph. Was observed. In the case of using a metal plate on which lithium nitride was formed for the final 120 minutes, Faraday efficiency showed a very high efficiency of 72%. The method for synthesizing ammonia based on a lithium superion conductor of the present invention can achieve very high synthesis efficiency of ammonia by forming lithium nitride on a lithium thin film metal plate produced electrochemically and simply immersing it.

Figure 6 shows the synthesis of ammonia using cesium additives. In the step of manufacturing the lithium thin metal plate, cesium was used as an additive to compare the amount of ammonia synthesis depending on whether an additive was added. The cesium additive was added at a molar concentration of 0.03 (0.049 g in a total 7 ml solution), and was performed in the same manner as described above, except for adding cesium. As a result, it can be confirmed that the amount of ammonia synthesis when cesium was included during electrodeposition of lithium is improved compared to when cesium is not added.

Although the exemplary embodiments of the present application have been described in detail above, the scope of the present application is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present application defined in the following claims are also provided. It belongs to.

All technical terms used in the present invention, unless defined otherwise, are used in the sense as commonly understood by those skilled in the art in the relevant field of the present invention. The contents of all publications described by reference herein are incorporated into the present invention.

1. Electrochemical cell
10. Lithium super-ion conductor
11.Oxide part
12. Cathode
100. Oxide electrode
110. Oxide solution
200. Cathode
201.Lithium thin metal plate
202. Lithium nitride thin film metal plate
210. Reducing cathode solution
300. Washing liquid
501.Section 1
502. Second Section
503. Section 3

Claims (12)

Lithium super-ion conductor based ammonia synthesis method,
The method includes the steps of preparing a lithium thin metal plate by electrodepositing lithium on one side of a cathode by using an electrochemical cell in which the anode part and the cathode part are partitioned by a lithium superion conductor;
Washing the lithium thin film metal plate;
A lithium nitride thin film metal plate production step of heating the lithium thin film metal plate which has undergone the washing step in a nitrogen atmosphere reactor to form lithium nitride (Li ₃ N) on the lithium thin film; And
Comprising the step of supporting the lithium nitride thin film metal plate in sulfuric acid (H ₂ SO ₄ ) solution to synthesize ammonia,
The anode part includes an anode and an anode solution, and the cathode part includes a cathode and a cathode solution,
The anode solution is an aqueous solution of Li ₂ SO ₄ , and lithium ions passed by a lithium superion conductor are coated on the cathode,
The solution that has undergone the ammonia synthesis step is reused as an anode solution,
The cathode solution includes a lithium salt, an organic solvent and an additive,
The additive is at least one selected from the group consisting of sodium, potassium, cesium, rubidium, magnesium, potassium, strontium, and fluoroethylene carbonate (FEC),
Method for synthesizing ammonia based on lithium superion conductors.
A method for synthesizing ammonia using a compartmentalized ammonia synthesis device based on a lithium superion conductor,
The method has a rotary cathode as a central axis, and a cylindrical reaction device divided into a first compartment, a second compartment, and a third compartment based on the cathode, in the first compartment, an oxide electrode and superion in electrolyte Positioning the conductor so as to face the cathode and depositing a lithium thin film on the cathode;
Forming a lithium nitride thin film by rotating the portion where the lithium thin film is formed into a second compartment and supplying nitrogen gas and heating it; And
Comprising the step of synthesizing ammonia by rotating the portion where the lithium nitride thin film is formed into a third compartment and contacting with an acid solution,
The electrolyte includes Li ₂ SO ₄ and additives,
Li ₂ SO ₄ produced in the step of synthesizing the ammonia is supplied to the first compartment and reused,
The third compartment is provided with an ammonium selective membrane,
Method for synthesizing ammonia based on lithium superion conductors.
The method according to claim 1 or 2,
The oxide electrode is Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Os , Ir, Pt, and one or more alloys selected from the group consisting of Au,
The cathode is at least one alloy selected from the group consisting of Ti, Mo, Fe, Co, Ni, Cu, Ag and Zn,
Method for synthesizing ammonia based on lithium superion conductors.
According to claim 1,
The lithium salt is lithium perchlorate, lithium dithionite, lithium sulfate, lithium tetrafluoroborate, lithium hexafluorophosphate, lithium bromide and lithium chloride, lithium bistrifluoromethanesulfonylimide (LiTFSI), lithium bis At least one selected from the group consisting of fluoromethanesulfonylimide (LiFSI) and lithium bisoxalateborate (LiBOB),
Method for synthesizing ammonia based on lithium superion conductors.
According to claim 1,
The organic solvent is at least one selected from the group consisting of propylene carbonate, ethylene carbonate, dimethyl carbonate, 1,3-dioxolane (DOL), and a solvent containing dimethoxyethane (DME) ,
Method for synthesizing ammonia based on lithium superion conductors.
According to claim 2,
The additive includes one or more additives selected from the group consisting of sodium, potassium, cesium, rubidium, magnesium, potassium, strontium, and fluoroethylene carbonate (FEC),
Method for synthesizing ammonia based on lithium superion conductors.
According to claim 1,
The washing is performed using 2-methyl tetrahydrofuran,
Method for synthesizing ammonia based on lithium superion conductors.
The method according to claim 1 or 2,
The heating is performed at 200°C to 230°C for 30 minutes to 1 hour,
Method for synthesizing ammonia based on lithium superion conductors.
According to claim 2,
The acid solution is H ₂ SO ₄ ,
Method for synthesizing ammonia based on lithium superion conductors.
According to claim 1,
Reusing the metal plate that has undergone the step of synthesizing ammonia as a cathode,
Method for synthesizing ammonia based on lithium superion conductors.
The method according to claim 1 or 2,
The electrodeposition is performed for 5 to 20 minutes,
Method for synthesizing ammonia based on lithium superion conductors.
According to claim 2,
The step of synthesizing the ammonia further includes the step of temporarily converting ammonium to ammonia gas by adjusting the pH to 10 or more,
The ammonium selective membrane is one gas permeable membrane selected from the group consisting of polypropylene (PP), polyvinilidenefluoride (PVDF) and polytetrafluoroethylene (PTFE),
Method for synthesizing ammonia based on lithium superion conductors.

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