Electrolytic carbon production system

Abstract

The invention provides an electrolytic carbon production system which comprises an electrolytic tank, an anode, a cathode, a molten electrolyte and an electrolyte membrane, and the anode, the cathode, the molten electrolyte and the electrolyte membrane are arranged in the electrolytic tank. The electrolyte membrane is arranged in the molten electrolyte and divides the molten electrolyte into an electrolyte cathode part and an electrolyte anode part, the cathode is arranged in the electrolyte cathode part, and the anode is arranged in the electrolyte anode part; the electrolytic carbon production system further comprises an air inlet pipe and / or a feeding pipe, an outlet of the air inlet pipe and / or the feeding pipe is close to the cathode, carbon dioxide and / or carbon monoxide enters the electrolytic bath through the air inlet pipe, carbon generated by electrochemical reduction treatment of the carbon dioxide and / or the carbon monoxide is enriched in the cathode, and the cathode is communicated with the cathode. Carbonate enters the electrolytic bath through the feeding pipe, and carbon generated by electrochemical reduction treatment of the carbonate is enriched in the cathode.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of new energy, and particularly relates to an electrolytic carbon production system. BACKGROUND

[0002] Solid fuel is easier to keep and transport than liquid fuel, is safer, and development of a new type of solid fuel to replace traditional coal and liquid fuel is an important direction in the field of low-carbon environmental protection. Regenerated carbon is the closest environmental protection type high-density secondary energy carrier to regenerated silicon fuel. Both regenerated carbon and regenerated silicon can be used as high-calorific-value energy for long-term and large-scale storage, do not need any chemical process processing, and do not need additional transportation systems for transportation. Only the transportation system of the coal industry needs to be used, and through railways, highways and waterway channels, the channel for large-scale energy transportation can be solved, and the transportation cost and transportation capacity are far more than the efficiency and capacity of high-voltage power transmission.

[0003] The patent proposes a carbon material production system, which can replace hydrogen and energy storage batteries as renewable system zero-carbon emission fuel secondary energy, and the carbon material has no heavy metal pollution, coal slag, sulfur dioxide, nitrogen oxides and other pollutants. In addition, the carbon material produced by the system also has no environmental pollution and high cost of coal mining and chemical industry.

[0004] The present application provides an electrolytic carbon production system, which uses the most abundant carbonates such as marble and limestone, and carbon monoxide or carbon dioxide gas to obtain a large amount of renewable carbon below 700 degrees Celsius, and at the same time obtains an oxide raw material for carbon cycle regeneration, achieving the goal of zero-cost carbon sequestration and low-cost carbon production. SUMMARY

[0005] The application provides an electrolytic carbon production system to achieve the above and other related purposes.

[0006] The first aspect of the application provides an electrolytic carbon production system, which comprises an electrolytic cell, an anode, a cathode, a molten electrolyte and an electrolyte membrane arranged in the electrolytic cell. The electrolytic cell is provided with the molten electrolyte, the electrolyte membrane is arranged in the molten electrolyte and divides the molten electrolyte into an electrolyte cathode part and an electrolyte anode part, the cathode is arranged in the electrolyte cathode part, and the anode is arranged in the electrolyte anode part.

[0007] The electrolytic carbon system further comprises a gas inlet pipe and / or a feed pipe, the outlet of the gas inlet pipe and / or the feed pipe is close to the cathode, carbon dioxide and / or carbon monoxide enters the electrolytic cell through the gas inlet pipe, the carbon dioxide and / or the carbon monoxide is enriched with carbon generated by electrochemical reduction treatment in the cathode, and carbonate enters the electrolytic cell through the feed pipe, the carbonate is enriched with carbon generated by electrochemical reduction treatment in the cathode.

[0008] Preferably, the material of the cathode is selected from at least one of the following:

[0009] (1) at least one metal element of tin, zinc, bismuth, aluminum, magnesium, gallium and indium;

[0010] (2) an alloy composed of two or more of tin, zinc, bismuth, aluminum, magnesium, gallium and indium;

[0011] (3) at least one metal oxide of tin, zinc, bismuth, aluminum, magnesium, gallium and indium.

[0012] Preferably, the material of the cathode includes one of tin, zinc and bismuth.

[0013] Preferably, the material of the cathode includes one of tin-zinc alloy, tin-gallium alloy, tin-bismuth alloy, tin-indium alloy, and zinc-aluminum alloy.

[0014] Preferably, the material of the cathode includes one of Sn91Zn9 alloy, Sn80Ga20 alloy, Sn70Bi30 alloy, Sn49In51 alloy and Zn95Al5 aluminum alloy.

[0015] Preferably, the material of the cathode includes one of tin oxide and zinc oxide, tin oxide and gallium oxide, tin oxide and bismuth oxide, tin oxide and indium oxide, and zinc oxide and aluminum oxide composite oxide.

[0016] Preferably, the material of the cathode includes one of (SnO2) 0.766 (ZnO) 0.137 , (SnO2) 0.674 (Ga2O3) 0.285 , (SnO2) 0.589 (Bi2O3) 0.096 , (SnO2) 0.412 (In2O3) 0.443 and (ZnO) 1.45 (Al2O3) 0.185 .

[0017] Preferably, the cathode is a liquid cathode, the cathode portion of the electrolyte is arranged above the liquid cathode, a liquid-liquid interface is formed between the cathode portion of the electrolyte and the liquid cathode, the carbon is generated at the liquid-liquid interface by electrochemical reduction and then floats on the liquid surface of the cathode portion of the electrolyte.

[0018] Preferably, the working voltage of the electrolytic carbon system is 1-2V when the electrolytic carbon system is used to produce carbon.

[0019] Preferably, when the material of the cathode includes at least one metal oxide of tin, zinc, bismuth, aluminum, magnesium, gallium and indium, a reduction voltage is applied to the cathode to reduce the metal oxide in the cathode to metal before the electrolytic carbon production, and the reduction voltage of the electrolytic carbon system is 1.5-5V.

[0020] Preferably, the material of the anode includes a first component, the first component is a metal oxide with oxygen defects or a perovskite oxide; the metal oxide with oxygen defects includes one or more of SnO 2-X , ZrO 2-X , TiO 2-x , CeO 2-X , SiO 2-x , Bi2O 3-x , MnO 2-x , CuO 1-x , Fe2O 3-x , Ni2O 3-x , Co2O 3-x , wherein x=0.001-1; the perovskite oxide includes at least one of LaMO3, La 1-x Ca x MO3, La 1-x Sr x MO3 and La 0.1 Sr 0.9-x Ca x MO3, wherein M is selected from at least one of Mn, Fe, Ni, Co, Cu, and x=0.1-0.9.

[0021] Preferably, the metal oxide with oxygen defects includes one of MnO 2-x , CuO 1-x and Ni2O 3-x .

[0022] Preferably, the metal oxide with oxygen defects includes MnO 2-x and CuO in a molar ratio of 1:0.2-1:9.1-x MnO 2-x and Ni2O 3-x MnO 2-x and Fe2O 3-x MnO 2-x and Co2O 3-x CuO 1-x and Ni2O 3-x Fe2O 3-x and Ni2O 3-x .

[0023] Preferably, the perovskite oxide comprises at least one of LaMnO3, LaCoO3, LaNiO3, LaMn 0.5 Cu 0.5 O3, LaMn 0.5 Ni 0.5 O3, La 0.5 Ca 0.5 MnO3, La 0.5 Ca 0.5 CoO3, La 0.5 Ca 0.5 FeO3, La 0.5 Ca 0.5 NiO3, and La 0.1 Sr 0.4 Ca 0.5 MnO3.

[0024] Preferably, the material of the anode further comprises a second component, and the mass ratio of the first component to the second component is 1:0.2-1:5; wherein

[0025] The second component comprises ceria-doped material or PN-type composite material;

[0026] The ceria-doped material comprises oxide-doped ceria, and the oxide in the oxide-doped ceria is at least one of lanthanum oxide, samarium oxide, gadolinium oxide, magnesium oxide, calcium oxide, and strontium oxide, and the molar ratio of the oxide to the oxide-doped ceria is 5%-20%,

[0027] The PN-type composite material comprises a PN semiconductor oxide mixture, the PN semiconductor oxide mixture comprises a P-type semiconductor oxide and an N-type semiconductor oxide, a mass ratio of the P-type semiconductor oxide and the N-type semiconductor oxide is 1:0.1-1:10, the P-type semiconductor oxide comprises at least one of nickelous oxide, ferrous oxide, cuprous oxide, stannous oxide, manganous oxide, cerium sesquioxide and cobalt sesquioxide, and the N-type semiconductor oxide comprises at least one of nickel sesquioxide, iron sesquioxide, cobalt sesquioxide, cupric oxide, manganese dioxide, tin dioxide, titanium dioxide, silicon dioxide, zinc oxide, gallium sesquioxide and aluminum sesquioxide.

[0028] Preferably, the cerium dioxide doped material comprises the oxide doped cerium dioxide and a salt additive, a mass ratio of the salt additive and the cerium dioxide doped material is 10-30wt%, or

[0029] The PN-type composite material comprises the PN semiconductor oxide mixture and a salt additive, a mass ratio of the salt additive and the PN-type composite material is 10-30wt%; wherein

[0030] The salt additive comprises at least one of sodium carbonate, potassium carbonate, lithium carbonate, sodium chloride, potassium chloride, calcium chloride, lithium sulfate, sodium sulfate and lithium sodium sulfate.

[0031] Preferably, the electrolyte anode part is arranged between the anode and the electrolyte membrane, the anode comprises a first surface in contact with the electrolyte anode part, a second surface in contact with air, and an intermediate part arranged between the first surface and the second surface, the first surface is a dense structure, and the second surface and at least part of the intermediate part are porous structures.

[0032] Preferably, the anode is entirely a porous structure, and a porosity of the anode is 30%-60%.

[0033] Preferably, the molten electrolyte comprises a carbonate, or a chloride, or a sulfate; wherein

[0034] The carbonate comprises sodium carbonate, or potassium carbonate, or lithium carbonate, or a mixed molten salt of lithium carbonate and sodium carbonate, or a mixed molten salt of lithium carbonate and potassium carbonate, or a mixed molten salt of sodium carbonate and potassium carbonate, or a ternary mixed molten salt of lithium carbonate, sodium carbonate and potassium carbonate.

[0035] The chloride includes a first type of chloride, or a composite of the first type of chloride and a second type of chloride; when the chloride molten salt includes the first type of chloride, the first type of chloride is calcium chloride, or magnesium chloride, or lithium chloride; when the chloride molten salt includes the composite of the first type of chloride and the second type of chloride, the first type of chloride is one or two of calcium chloride, magnesium chloride and lithium chloride, and the second type of chloride is sodium chloride and / or potassium chloride;

[0036] The sulfate includes lithium sulfate, or a sodium-lithium sulfate mixed molten salt, or a lithium-potassium sulfate mixed molten salt, or a lithium-sodium-potassium sulfate ternary molten salt.

[0037] Preferably, the molten electrolyte includes a chloride, the first type of chloride in the composite includes calcium chloride or magnesium chloride, and the molar ratio of the calcium chloride or the magnesium chloride to the composite is not less than 20%.

[0038] Preferably, in the lithium-sodium-potassium carbonate ternary mixed molten salt, the mass ratio of potassium carbonate: lithium carbonate: sodium carbonate is 3:1:6, or 3:2:5, or 4:2:4, or 5:2:3.

[0039] Preferably, in the composite of the first type of chloride and the second type of chloride, the molar ratio of sodium chloride: calcium chloride is 1:1, or the molar ratio of potassium chloride: magnesium chloride is 1:1 or 2:1.

[0040] Preferably, in the sodium-lithium sulfate mixed molten salt, the mass ratio of sodium sulfate: lithium sulfate is 1:0.1 to 1:10.

[0041] Preferably, the material of the electrolyte film includes a ceria-doped material or a PN-type composite material; wherein

[0042] The ceria-doped material includes an oxide-doped ceria, the oxide in the oxide-doped ceria is selected from at least one of lanthanum oxide, samarium oxide, gadolinium oxide, magnesium oxide, calcium oxide and strontium oxide, and the molar ratio of the oxide to the oxide-doped ceria is 5%-20%,

[0043] The PN type composite material comprises a PN semiconductor oxide mixture, the mass ratio of P-type semiconductor oxide and N-type semiconductor oxide in the PN semiconductor oxide mixture is 1:0.1-1:10, the P-type semiconductor oxide comprises at least one of nickelous oxide, ferrous oxide, cuprous oxide, stannous oxide, manganous oxide, cerium sesquioxide and cobalt sesquioxide, and the N-type semiconductor oxide comprises at least one of nickel sesquioxide, iron sesquioxide, cobalt sesquioxide, cupric oxide, manganese dioxide, tin dioxide, titanium dioxide, silicon dioxide, zinc oxide, gallium sesquioxide and aluminum sesquioxide.

[0044] Preferably, the cerium dioxide doped material comprises the oxide doped cerium dioxide and a salt additive, the mass ratio of the salt additive to the cerium dioxide doped material is 10-30wt%, or

[0045] The PN type composite material comprises the PN semiconductor oxide mixture and a salt additive, the mass ratio of the salt additive to the PN type composite material is 10-30wt%; wherein

[0046] The salt additive comprises at least one of sodium carbonate, potassium carbonate, lithium carbonate, sodium chloride, potassium chloride, calcium chloride, lithium sulfate, sodium sulfate and sodium lithium sulfate.

[0047] Preferably, the working temperature of the electrolytic carbon system is 350-700 degrees Celsius.

[0048] Preferably, the electrolytic carbon system further comprises a carbon fixation oxide collecting device, when the feed pipe is connected to the carbonate, the carbonate is further converted into alkali metal oxide and / or alkaline earth metal oxide by electrochemical reduction treatment, the alkali metal oxide and / or the alkaline earth metal oxide absorbs carbon dioxide, or the alkali metal oxide and / or the alkaline earth metal oxide absorbs carbon dioxide after being dissolved in water.

[0049] The beneficial effects of the present application are:

[0050] I. The electrolytic carbon system has the characteristics of low working voltage and high energy conversion efficiency. The reasons for reducing the working voltage of the electrolytic carbon system are as follows:

[0051] Firstly, the conductivity of the molten electrolyte is higher than that of aqueous solution or ionic liquid or eutectic solvent, and the internal resistance of the electrolytic cell is small, so the working voltage can be reduced.

[0052] Secondly, the conductivity of the electrolyte film is also higher than that of the traditional YSZ solid electrolyte, and the working temperature is lower, so the internal resistance of the electrolytic cell is further reduced, and the working voltage can be further reduced.

[0053] Then, due to the choice of molten electrolyte, the operating temperature of the electrolytic cell is 350-700 degrees Celsius. At this temperature, the activity of the anode material is higher and the oxygen evolution potential is lower, which can further reduce the operating voltage.

[0054] Finally, since the cathode is a metal with high conductivity, and the interface resistance is even lower when the cathode is a liquid metal, the operating voltage is further reduced.

[0055] Second, the electrolytic carbon production system features high current efficiency and high product selectivity. It utilizes a molten electrolyte, eliminating the side reaction that generates hydrogen gas, resulting in high current efficiency. Furthermore, due to the spatial isolation provided by the intermediate solid electrolyte membrane, the carbon produced will not diffuse to the anode side for oxidation, and the oxygen on the anode side will not diffuse to the cathode side to react with the products, thus eliminating consumption and further increasing electrolysis efficiency. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of the structure of an electrolytic carbon production system according to an embodiment of the present invention. Detailed Implementation

[0057] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0058] It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding and reading. They are not intended to limit the implementation conditions of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effectiveness and objectives of the invention, should still fall within the scope of the technical content disclosed in the invention. Furthermore, the terms "first," "second," and "third" in this specification are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0059] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0060] Example 1

[0061] An embodiment of the present invention provides an electrolytic carbon production system 10. The electrolytic carbon production system 10 includes an electrolytic cell 1 and an anode 2, a cathode 3, a molten electrolyte 4, and an electrolyte membrane 5 disposed within the electrolytic cell 1. The electrolytic cell 1 contains the molten electrolyte 4, and the electrolyte membrane 5 is disposed within the molten electrolyte 4, dividing the molten electrolyte 4 into an electrolyte cathode portion 41 and an electrolyte anode portion 42. The cathode 3 is disposed within the electrolyte cathode portion 41 of the molten electrolyte 4, and the anode 42 is disposed within the electrolyte anode portion 42 of the molten electrolyte 4. The electrolytic carbon production system 10 also includes an air inlet pipe 6 and / or a feed pipe 6. The outlet of the air inlet pipe 6 and / or the feed pipe 6 is close to the cathode 3. For example, the outlet of the air inlet pipe 6 and / or the feed pipe 6 can be inside the liquid cathode or above the surface of the liquid cathode. Carbon dioxide and / or carbon monoxide enter the electrolytic cell 1 through the inlet pipe 6. The carbon generated by the electrochemical reduction treatment of carbon dioxide and / or carbon monoxide is enriched in the cathode 3. Carbonate enters the electrolytic cell 1 through the feed pipe 6. The carbon generated by the electrochemical reduction treatment of carbonate is enriched in the cathode 3.

[0062] In one embodiment of the present invention, the carbonate is sodium carbonate, potassium carbonate, calcium carbonate, magnesium carbonate or other carbonates, or a mixture of the above carbonates, and the carbonate is in powder or micro-particle form.

[0063] In one embodiment of the present invention, the cathode 3 is made of at least one metal and / or at least one metal oxide selected from tin, zinc, bismuth, aluminum, magnesium, gallium, and indium. The cathode 3 is a liquid cathode, and an electrolyte cathode portion 41 is disposed above the liquid cathode, forming a liquid-liquid interface 8 between the electrolyte cathode portion 41 and the liquid cathode. Carbon is generated at the liquid-liquid interface 8 through electrochemical reduction and then floats on the liquid surface of the electrolyte cathode portion 41. By selecting the appropriate cathode material, the voltage required for electrolytic carbon production can be effectively reduced.

[0064] Preferably, the cathode is made of one of tin, zinc, and bismuth.

[0065] Preferably, the cathode is made of one of the following materials: tin-zinc alloy, tin-gallium alloy, tin-bismuth alloy, tin-indium alloy, and zinc-aluminum alloy.

[0066] Preferably, the cathode is made of one of the following materials: Sn91Zn9 alloy, Sn80Ga20 alloy, Sn70Bi30 alloy, Sn49In51 alloy, and Zn95Al5 aluminum alloy. Taking Sn91Zn9 alloy as an example, Sn91Zn9 alloy means that the mass fraction of tin in the alloy is 91% and the mass fraction of zinc is 9%.

[0067] Preferably, the cathode material includes one of tin oxide and zinc oxide, tin oxide and gallium oxide, tin oxide and bismuth oxide, tin oxide and indium oxide, and a composite oxide of zinc oxide and aluminum oxide.

[0068] Preferably, the cathode is made of (SnO2). 0.766 (ZnO) 0.137 (SnO2) 0.674 (Ga2O3) 0.285 (SnO2) 0.589 (Bi2O3) 0.096 (SnO2) 0.412 (In2O3) 0.443 and (ZnO) 1.45 (Al2O3) 0.185 One of them. (SnO2) 0.766 (ZnO) 0.137 Let's take (SnO2) as an example. 0.766 (ZnO) 0.137 This indicates that the number of moles of SnO2 is 0.766 and the number of moles of ZnO is 0.137.

[0069] In one embodiment of the present invention, when the cathode is made of an alloy, the alloy is weighed out according to a specific ratio and melted separately. Then, the high-melting-point metal is poured into the low-melting-point metal, stirred evenly, and cooled to obtain an alloy electrode. When the cathode is made of two or more metal oxides, the alloy is weighed out according to a specific ratio, mixed, ground into powder, pressed into sheets at a pressure of 10-50 MPa, and then sintered at 900-1000 degrees Celsius. During electrolysis, the cathode is placed at the bottom of the molten salt on the cathode side and connected to the cathode of the electrolysis power supply with a metal wire. Electrolysis is first performed at 1.5-5 volts for 2-4 hours to obtain a liquid metal cathode.

[0070] In one embodiment of the present invention, the operating voltage of the electrolytic carbon production system is 1-2V during electrolytic carbon production. Typical non-limiting operating voltages are 1V, 1.1V, 1.2V, 1.3V, 1.4V, 1.5V, 1.6V, 1.7V, 1.8V, 1.9V, or 2.0V. Existing electrolytic carbon production systems have voltages higher than 1-2V. The present invention, through the selection of the molten electrolyte, cathode, anode, and electrolyte membrane, can reduce the operating voltage of electrolytic carbon production, thus saving energy. First, the conductivity of the molten electrolyte is higher than that of aqueous solutions, ionic liquids, or eutectic solvents, resulting in lower internal resistance of the electrolytic cell and a lower operating voltage. Second, the conductivity of the electrolyte membrane is also higher than that of traditional YSZ solid electrolytes, and the operating temperature is lower, further reducing the internal resistance of the electrolytic cell and further lowering the operating voltage. Then, due to the choice of molten electrolyte, the electrolytic cell operates at a temperature of 350-700 degrees Celsius. At this temperature, the anode material exhibits higher activity and a lower oxygen evolution potential, which can further reduce the operating voltage. Finally, because the cathode is a metal with high conductivity, and when the cathode is a liquid metal, the interfacial resistance is even lower, thus further reducing the operating voltage.

[0071] In one embodiment of the present invention, when the cathode material includes at least one metal oxide selected from tin, zinc, bismuth, aluminum, magnesium, gallium, and indium, a reduction voltage is applied to the cathode before electrolytic carbon production to reduce the metal oxide in the cathode to a metal. The reduction voltage of the electrolytic carbon production system is 1.5-5V. Although the reduction voltage is higher than the working voltage, the cathode reduction process is relatively short, generally 2-4 hours. When the electrode sheet of solid oxide or mixed oxide has completely turned into a liquid state, it can be proven that the liquid cathode preparation is complete.

[0072] In one embodiment of the present invention, the molten electrolyte comprises a carbonate, a chloride, or a sulfate.

[0073] Preferably, the carbonate includes sodium carbonate, potassium carbonate, lithium carbonate, a mixed molten salt of lithium carbonate and sodium carbonate, a mixed molten salt of lithium carbonate and potassium carbonate, a mixed molten salt of sodium carbonate and potassium carbonate, or a ternary mixed molten salt of lithium carbonate, sodium carbonate and potassium carbonate.

[0074] Preferably, the chloride includes a first type of chloride, or a complex of a first type of chloride and a second type of chloride; when the chloride molten salt includes the first type of chloride, the first type of chloride is calcium chloride, or magnesium chloride, or lithium chloride; when the chloride molten salt includes the complex of the first type of chloride and the second type of chloride, the first type of chloride is one or two of calcium chloride, magnesium chloride and lithium chloride, and the second type of chloride is sodium chloride and / or potassium chloride.

[0075] Preferably, the sulfate includes lithium sulfate, or a mixed molten salt of sodium sulfate and lithium sulfate, or a mixed molten salt of lithium sulfate and potassium sulfate, or a ternary molten salt of lithium sulfate, sodium sulfate, and potassium sulfate.

[0076] Preferably, the molten electrolyte comprises a chloride, and the first type of chloride in the composite comprises calcium chloride or magnesium chloride, wherein the molar proportion of calcium chloride or magnesium chloride in the composite is not less than 20%. Preferably, the molar proportion of calcium chloride or magnesium chloride in the composite is not less than 30%. Preferably, the molar proportion of calcium chloride or magnesium chloride in the composite is 50%.

[0077] Preferably, in the complex of the first type of chloride and the second type of chloride, the molar ratio of sodium chloride to calcium chloride is 1:1, or the molar ratio of potassium chloride to magnesium chloride is 1:1 or 2:1.

[0078] Preferably, in the ternary mixed molten salt of lithium carbonate, sodium carbonate, and potassium carbonate, the mass ratio of potassium carbonate:lithium carbonate:sodium carbonate is 3:1:6, or 3:2:5, or 4:2:4, or 5:2:3.

[0079] Preferably, in the sodium sulfate to lithium sulfate mixed molten salt, the mass ratio of sodium sulfate to lithium sulfate is from 1:0.1 to 1:10. Typical non-limiting mass ratios of sodium sulfate to lithium sulfate are 1:0.1, 1:0.5, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10.

[0080] The preparation method of molten electrolyte can be found in the following exemplary steps: Weigh the salts according to the proportion, mix them evenly, heat to 600-900 degrees Celsius, after melting, stir evenly, let stand and keep warm for 4 hours, cool to obtain molten electrolyte, and then crush and grind it into powder.

[0081] The preparation method of molten electrolyte can also refer to the following exemplary steps: The preparation method of binary or multi-component molten salt is to weigh each component according to the mass ratio or molar ratio, then mix and grind them into powder, then put them in a crucible and heat them to 700-900 degrees Celsius, melt them and stir them evenly, let them stand for 2-4 hours and then cool them, and then crush them into powder for later use.

[0082] In one embodiment of the present invention, the anode 2 is made of a first component, which is a metal oxide with oxygen defects or a perovskite oxide. The metal oxide with oxygen defects includes tin oxide (SnO). 2-X Zirconium oxide (ZrO) 2-X Titanium oxide (TiO) 2-x Cerium oxide (CeO) 2-X Silica SiO 2-x Bismuth oxide (Bi2O) 3-x Manganese oxide (MnO) 2-x Copper oxide (CuO) 1-x Iron oxide (Fe2O) 3-x Nickel oxide (Ni2O) 3-x Cobalt oxide (Co2O) 3-x One or more of the following, wherein x = 0.001-1. The perovskite oxide includes LaMO3, La... 1-x Ca x MO3, La 1-x Sr x MO3 and La 0.1 Sr 0.9-x Ca x At least one of MO3, wherein M is selected from at least one of Mn, Fe, Ni, Co, Cu, and x = 0.1-0.9, wherein typical non-limiting operating voltages are 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0083] Preferably, the metal oxide with oxygen vacancies includes manganese oxide (MnO).2-x Copper oxide (CuO) 1-x and nickel oxide Ni2O 3-x One of them.

[0084] Preferably, the oxygen-defective metal oxide comprises MnO in a molar ratio of 1:0.2-1:9. 2-x and CuO 1-x MnO with a molar ratio of 1:0.2-1:9 2-x and Ni2O 3-x MnO with a molar ratio of 1:0.2-1:9 2-x and Fe2O 3-x MnO with a molar ratio of 1:0.2-1:9 2-x and Co2O 3-x CuO with a molar ratio of 1:0.2-1:9 1-x and Ni2O 3-x And Fe2O with a molar ratio of 1:0.2-1:9 3-x and Ni2O 3-x One of them.

[0085] Preferably, the perovskite oxide includes LaMnO3, LaCoO3, LaNiO3, and LaMn. 0.5 Cu 0.5 O3, LaMn 0.5 Ni 0.5 O3, La 0.5 Ca 0.5 MnO3, La 0.5 Ca 0.5 CoO3, La 0.5 Ca 0.5 FeO3, La 0.5 Ca 0.5 NiO3 and La 0.1 Sr 0.4 Ca 0.5 At least one of MnO3.

[0086] Preferably, the anode material further includes a second component, and the mass ratio of the first component to the second component is 1:0.2 to 1:5; wherein the second component includes cerium dioxide doped material or PN-type composite material. The second component is a solid electrolyte, which improves ionic conductivity and provides some electronic conductivity, reduces the resistance of the anode material, and can reduce the voltage of the electrolytic carbon production system. Typical non-limiting mass ratios of the first and second components are 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, or 1:5.

[0087] Preferably, the cerium dioxide doped material includes oxide-doped cerium dioxide, wherein the oxide in the oxide-doped cerium dioxide is selected from at least one of lanthanum oxide, samarium oxide, gadolinium oxide, magnesium oxide, calcium oxide and strontium oxide, and the molar ratio of oxide to oxide-doped cerium dioxide is 5%-20%. Typical but non-limiting molar ratios of oxide to oxide-doped cerium dioxide in this invention are 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%.

[0088] Preferably, the PN-type composite material comprises a PN semiconductor oxide mixture, wherein the PN semiconductor oxide mixture comprises P-type semiconductor oxide and N-type semiconductor oxide, and the mass ratio of the P-type semiconductor oxide to the N-type semiconductor oxide is 1:0.1-1:10. The P-type semiconductor oxide comprises at least one of nickel oxide, ferrous oxide, cuprous oxide, tin oxide, manganese oxide, cerium oxide, and cobalt tetroxide. The N-type semiconductor oxide comprises at least one of nickel oxide, ferric oxide, cobalt oxide, copper oxide, manganese dioxide, tin dioxide, titanium dioxide, silicon dioxide, zinc oxide, gallium oxide, and aluminum oxide. Typical, but not limiting, mass ratios of P-type and N-type semiconductor oxides in this invention are 1:0.1, 1:0.5, 1:1.0, 1:1.2, 1:1.5, 1:1.8, 1:2.0, 1:2.2, 1:2.5, 1:2.7, 1:3.0, 1:3.2, 1:3.6, 1:4.0, 1:4.5, 1:5.0, 1:5.3, 1:5.5, 1:5.8, 1:6.0, 1:6.2, 1:6.5, 1:7.0, 1:7.2, 1:7.6, 1:8.0, 1:8.5, 1:9.0, 1:9.1, 1:9.2, 1:9.5, 1:9.8, or 1:10.

[0089] Preferably, in the second component, the cerium dioxide doped material comprises oxide-doped cerium dioxide and a salt additive, wherein the mass ratio of the salt additive to the cerium dioxide doped material is 10-30 wt%. Typical, but not limiting, mass ratios of the salt additive to the cerium dioxide doped material in this invention are 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or 30%. The salt additive comprises at least one of sodium carbonate, potassium carbonate, lithium carbonate, sodium chloride, potassium chloride, calcium chloride, lithium sulfate, sodium sulfate, and sodium lithium sulfate. Adding a salt additive to the second component can further increase the ion conductivity of the solid electrolyte and improve its electrical conductivity. Simultaneously, it can reduce the resistance of the solid electrolyte in the mid-temperature range of 350-700 degrees Celsius, thereby lowering the operating temperature of the solid electrolyte. Even without the addition of salt additives, it can still have ionic conductivity, which is still better than that of solid materials such as high-temperature SOEC, but lower than that of composite electrolytes with added salt additives.

[0090] Preferably, in the second component, the PN-type composite material comprises the PN semiconductor oxide mixture and a salt additive, wherein the mass ratio of the salt additive to the PN-type composite material is 10-30 wt%. Typical, but not limiting, mass ratios of the salt additive to the PN-type composite material in this invention are 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or 30%. The salt additive comprises at least one of sodium carbonate, potassium carbonate, lithium carbonate, sodium chloride, potassium chloride, calcium chloride, lithium sulfate, sodium sulfate, and sodium lithium sulfate. Adding the salt additive to the second component can further increase the ion conductivity of the solid electrolyte, improve its conductivity, and further reduce its resistivity. Simultaneously, it can reduce the resistance of the solid electrolyte in the mid-temperature range of 350-700 degrees Celsius, thus lowering the operating temperature of the solid electrolyte. Even without the addition of salt additives, it can still have ionic conductivity, which is still better than that of solid materials such as high-temperature SOEC, but lower than that of composite electrolytes with added salt additives.

[0091] In one embodiment of the present invention, an electrolyte anode portion 42 is disposed between an anode 2 and an electrolyte membrane 5. The anode 2 includes a first surface 21 in contact with the electrolyte anode portion 42, a second surface 22 in contact with air, and an intermediate portion 23 disposed between the first surface 21 and the second surface 22. The first surface 21 has a dense structure, while the second surface 22 and the intermediate portion 23 have porous structures. The porosity of the porous structure is 30-80%, the pore size is 1-50 micrometers, and the thickness from the first surface to the second surface is 100-500 micrometers. The dense structure of the first surface prevents the molten electrolyte from overflowing. Oxygen ions are oxidized on the first surface. Under the action of an electric field, oxygen ions in the molten electrolyte enter the first surface and further migrate to the second surface. After gaining electrons, they generate oxygen and release oxygen at the solid-gas interface. It can be understood that the anode 2 is an air electrode or a gas diffusion electrode. In other embodiments, the anode is entirely a porous structure with a porosity of 30-60% and a suitable pore size to prevent leakage of the molten salt electrolyte.

[0092] Metal oxides with oxygen vacancies can be synthesized using a solid-state method, as illustrated in the following exemplary steps: directly weigh tin oxide (SnO). 2-X Zirconium oxide (ZrO) 2-X Titanium oxide (TiO) 2-x Cerium oxide (CeO) 2-X Silica SiO 2-x Bismuth oxide (Bi2O) 3-x Manganese oxide (MnO) 2-x Copper oxide (CuO) 1-x Iron oxide (Fe2O) 3-x Nickel oxide (Ni2O) 3-x Cobalt oxide (Co2O) 3-x One or two of the ingredients are mixed, ground evenly, sintered at a high temperature of 600-1100 degrees Celsius, cooled, and then pulverized to obtain a metal oxide with oxygen defects.

[0093] The preparation method of the porous metal oxide with oxygen defects can be described by the following exemplary steps: 10%-20% of ammonium bicarbonate, a pore-forming agent, is added to the metal oxide with oxygen defects obtained above. After mixing evenly, the mixture is pressed into tablets at a pressure of 10-50 MPa. Then, the tablets are heated to 150 degrees Celsius to decompose the pore-forming agent. The temperature is then further increased to 900-1100 degrees Celsius and maintained for 30 minutes to 2 hours to obtain the porous metal oxide with oxygen defects, which can be understood as obtaining a porous anode.

[0094] The preparation method of an anode (partially porous anode) with a first surface having a dense structure and a second surface and at least part of the middle part having a porous structure can be described by the following exemplary steps: place a metal oxide with oxygen defects into the bottom layer of a tablet press, then weigh the metal oxide with oxygen defects and 10%-20% of a pore-forming agent, mix them evenly and place them in the upper layer of the tablet press, press at a pressure of 10-50 MPa, then heat to 150 degrees Celsius to decompose the pore-forming agent, and continue to heat to 900-1100 degrees Celsius, and maintain for 30 minutes to 2 hours to obtain a partially porous anode.

[0095] The perovskite oxide can be prepared using the citric acid-sol-gel method, as illustrated by the following exemplary steps: Lanthanum nitrate, and one or two of the following: strontium nitrate, calcium nitrate, manganese nitrate (divalent manganese ions), ferric nitrate, cobalt nitrate, copper nitrate, and nickel nitrate, are dissolved separately in deionized water in a specific ratio and then mixed thoroughly. An appropriate amount of citric acid is added as a precipitant, and the mixture is stirred and sonicated in a 70°C water bath, then stirred again in a 70°C water bath until a colloid is formed. The mixture is then vacuum dried at 105°C for 12 hours and calcined at 800°C for 4 hours at a heating rate of 5°C per minute to obtain the perovskite oxide.

[0096] The preparation methods for porous anodes and partially porous anodes made of perovskite oxide materials can refer to the preparation methods for porous anodes and partially porous anodes made of metal oxide materials with oxygen defects described above.

[0097] The preparation method of the anode, which includes the second component and the first component, can be found in the following exemplary steps:

[0098] Weigh the first and second components in a mass ratio of 1:0.2 to 1:5, then add 10%-20% of the pore-forming agent ammonium bicarbonate, mix evenly, and compress into tablets at a pressure of 10-50 MPa. Then heat to 150 degrees Celsius to decompose the pore-forming agent, and continue heating to 900-1100 degrees Celsius, maintaining the temperature for 30 minutes to 2 hours to obtain a porous anode.

[0099] The preparation method of the partially porous anode, which includes the second component and the first component, can refer to the preparation method of the partially porous anode made of metal oxide material with oxygen defects described above.

[0100] In one embodiment of the present invention, the electrolyte membrane material includes cerium dioxide doped material or PN-type composite material.

[0101] Preferably, the cerium dioxide doped material includes oxide-doped cerium dioxide, wherein the oxide in the oxide-doped cerium dioxide is selected from at least one of lanthanum oxide, samarium oxide, gadolinium oxide, magnesium oxide, calcium oxide and strontium oxide, and the molar ratio of the oxide to the oxide-doped cerium dioxide is 5%-20%.

[0102] The PN-type composite material comprises a PN semiconductor oxide mixture, which includes P-type semiconductor oxide and N-type semiconductor oxide. The mass ratio of the P-type semiconductor oxide to the N-type semiconductor oxide is 1:0.1-1:10. The P-type semiconductor oxide includes at least one of nickel oxide, ferrous oxide, cuprous oxide, tin oxide, manganese oxide, cerium oxide, and cobalt tetroxide. The N-type semiconductor oxide includes at least one of nickel oxide, ferric oxide, cobalt oxide, copper oxide, manganese dioxide, tin dioxide, titanium dioxide, silicon dioxide, zinc oxide, gallium oxide, and aluminum oxide.

[0103] Preferably, the cerium dioxide doped material comprises oxide-doped cerium dioxide and a salt additive, wherein the mass ratio of the salt additive to the cerium dioxide doped material is 10-30 wt%. The salt additive includes at least one selected from sodium carbonate, potassium carbonate, lithium carbonate, sodium chloride, potassium chloride, calcium chloride, lithium sulfate, sodium sulfate, and sodium lithium sulfate. Adding the salt additive can further increase the ionic conductivity of the solid electrolyte, improve its conductivity, and further reduce its resistivity. Simultaneously, it can reduce the resistance of the solid electrolyte in the mid-temperature range of 350-700 degrees Celsius, thus lowering the operating temperature of the solid electrolyte. Even without the addition of the salt additive, the solid electrolyte can still exhibit ionic conductivity superior to that of high-temperature SOEC and other solid materials, but lower than that of composite electrolytes with added salt additives.

[0104] Preferably, the PN-type composite material comprises the PN semiconductor oxide mixture and a salt additive, wherein the mass ratio of the salt additive to the PN-type composite material is 10-30 wt%. The salt additive includes at least one selected from sodium carbonate, potassium carbonate, lithium carbonate, sodium chloride, potassium chloride, calcium chloride, lithium sulfate, sodium sulfate, and sodium lithium sulfate. Adding the salt additive can further increase the ionic conductivity of the solid electrolyte, improve its conductivity, and further reduce its resistivity. Simultaneously, it can reduce the resistance of the solid electrolyte in the mid-temperature range of 350-700 degrees Celsius, thus lowering the operating temperature of the solid electrolyte. Even without the addition of the salt additive, the solid electrolyte can still exhibit ionic conductivity superior to that of high-temperature SOEC and other solid materials, but lower than that of the composite electrolyte with the added salt additive.

[0105] The electrolyte membrane material includes cerium dioxide doped materials. When the cerium dioxide doped material includes oxide-doped cerium dioxide, the preparation method of the electrolyte membrane can refer to the preparation method of oxide-doped cerium dioxide described below. When the cerium dioxide doped material includes the oxide-doped cerium dioxide and salt additives, the preparation method of the electrolyte membrane can refer to the preparation method of the mixed material of oxide-doped cerium dioxide and salt additives described below.

[0106] The preparation of oxide-doped cerium dioxide can be achieved using either a co-precipitation method or a sol-gel method. The sol-gel method can be illustrated by the following steps: The precursor is cerium nitrate, and one or two of strontium nitrate, lanthanum nitrate, samarium nitrate, calcium nitrate, gadolinium nitrate, and magnesium nitrate, dissolved separately in deionized water according to their molar ratios, and then mixed thoroughly. An appropriate amount of citric acid as a precipitant is added, and the mixture is stirred and sonicated in a 70°C water bath, then stirred again in a 70°C water bath until a colloid is formed. The mixture is then vacuum dried at 105°C for 12 hours. Finally, it is calcined at 600°C for 2 hours at a heating rate of 10°C per minute, then cooled and pulverized to obtain oxide-doped cerium dioxide.

[0107] The preparation method of the oxide-doped cerium dioxide and salt additive mixture can be described by the following exemplary steps: the cerium dioxide dopant and the salt additive (e.g., sodium chloride) are mixed in a ratio of 10 wt%, 15 wt%, 20 wt%, 25 wt%, and 30 wt%, respectively, ground evenly, then pressed into tablets and sintered at 900 degrees Celsius to obtain the oxide-doped cerium dioxide and salt additive mixture.

[0108] The electrolyte membrane material includes PN-type composite materials. When the PN-type composite material includes a mixture of PN semiconductor oxides, the preparation method of the electrolyte membrane can refer to the preparation method of the PN semiconductor oxide mixture described below. When the PN-type composite material includes a mixture of PN semiconductor oxides and salt additives, the preparation method of the electrolyte membrane can refer to the preparation method of the mixture of PN semiconductor oxides and salt additives described below.

[0109] The preparation method of PN semiconductor oxide mixture can be carried out by solid-state synthesis. The solid-state synthesis method can be described by the following exemplary steps: select P-type semiconductor oxide and N-type semiconductor oxide, weigh them according to the designed ratio, grind them uniformly, sinter them at a high temperature of 900 degrees Celsius, and then grind them into powder after cooling to obtain PN semiconductor oxide mixture.

[0110] The preparation method of the mixed material of PN semiconductor oxide mixture and salt additive can be described by the following exemplary steps: First, heat the salt additive to 600-900 degrees Celsius to melt it, then mix the salt additive and PN semiconductor oxide mixture powder in proportion, stir evenly, cool and then pulverize to obtain the powder of the mixed material of PN semiconductor oxide mixture and salt additive, and then compress it to obtain the mixed material of PN semiconductor oxide mixture and salt additive.

[0111] In one embodiment of the present invention, the operating temperature of the electrolytic carbon production system is 350-700°C.

[0112] In one embodiment of the present invention, the electrolyte membrane and the molten electrolyte have one or more of the following characteristics:

[0113] (1) Total ionic conductivity greater than 0.01 S / cm;

[0114] (2) Oxygen ion conductivity greater than 0.0010 S / cm

[0115] (3) The mixed ionic conductivity of oxygen ions and hydrogen ions is greater than 0.01 S / cm.

[0116] In one embodiment of the present invention, the rate of introduction of carbon dioxide and / or carbon monoxide is 1-100 mL / min, and the rate of addition of carbonate is 0.5-10 g / h. Preferably, when the electrolysis current is 0.5-2 amperes, the rate of introduction of carbon dioxide and / or carbon monoxide is 1-100 mL / min, and the rate of addition of carbonate is 0.5-10 g / h. More preferably, when the electrolysis current is 1 ampere, the rate of introduction of carbon dioxide and / or carbon monoxide is 1-100 mL / min, and the rate of addition of carbonate is 0.5-10 g / h.

[0117] In one embodiment of the present invention, the electrolytic carbon production system 10 further includes a carbon oxide collection device. When carbonate is introduced into the feed pipe, the carbonate undergoes electrochemical reduction to generate alkali metal oxides and / or alkaline earth metal oxides. These alkali metal oxides and / or alkaline earth metal oxides absorb carbon dioxide, or they dissolve in water and then absorb carbon dioxide. The alkali metal oxides can be sodium oxide, potassium oxide, etc., and the alkaline earth metal oxides can be calcium oxide, magnesium oxide, etc. The products of carbonate electrolysis are carbon, as well as alkali metal oxides and / or alkaline earth metal oxides. These carbons are generated and accumulate at the liquid-liquid interface. When the carbon accumulates to a certain particle size, some will float to the surface of the molten salt or enter the molten salt. During collection, the alkali metal oxides and / or alkaline earth metal oxides, along with the carbon, can be collected together. Then, water is added, and the carbon and the generated hydroxides are separated to obtain pure carbon.

[0118] Specifically, alkali metal oxides and / or alkaline earth metals can absorb high concentrations of carbon dioxide from power plant exhaust or boiler exhaust at high temperatures, releasing a large amount of heat. This heat can be used for heating or maintaining the temperature of electrolysis systems, reducing power consumption in carbon electrolysis and improving electrolysis efficiency to 90%-100%. Alkali metals and / or alkaline earth metals readily dissolve in water at room temperature, forming sodium hydroxide, potassium hydroxide, calcium hydroxide, etc. When air is introduced, they absorb carbon dioxide to form sodium carbonate, potassium carbonate, and calcium carbonate, which can be used as raw materials for renewable carbon production.

[0119] In one embodiment of the present invention, the electrolytic carbon production system further includes an electrolytic power supply, which provides a high current and a DC voltage of 0-5 volts to the electrolytic carbon production system.

[0120] In one embodiment of the present invention, the electrolytic carbon production system further includes a temperature protection system. This system provides heating and cooling to the electrolytic system. Heating causes the molten salt to dissolve or undergo a phase change, increasing its ionic conductivity, while simultaneously controlling the system temperature to remain below the boiling point of the molten salt. The morphology and particle size of the electrolytic carbon material can also be controlled according to the temperature control system.

[0121] Experimental Example

[0122] Experimental Example 1: Carbon Monoxide Electrolysis Carbon Production System

[0123] The cathode is made of Zn95Al5 aluminum alloy with a melting point of 381 degrees Celsius. The preparation method involves heating 95 grams of zinc and 5 grams of aluminum to 430-450 degrees Celsius, then adding the aluminum into the zinc liquid and stirring continuously until it is completely dissolved. This process is continued for 4 hours, after which the mixture is cooled and ready for use.

[0124] The molten electrolyte is a molten carbonate, specifically a ternary molten salt of sodium carbonate, potassium carbonate, and lithium carbonate (melting point between 380-440 degrees Celsius). The mass ratio of potassium carbonate:lithium carbonate:sodium carbonate is 3:1:6, 3:2:5, 4:2:4, or 5:2:3. The melting points of these ternary mixed molten salts with different mass ratios are all below 397 degrees Celsius, with the lowest being 373 degrees Celsius. An experimental molten salt with a potassium carbonate:lithium carbonate:sodium carbonate mass ratio of 3:1:6 was selected, as this ternary mixed molten salt has the lowest lithium carbonate content and is therefore less expensive.

[0125] Preparation method of molten electrolyte: Weigh 300g of potassium carbonate, 100g of lithium carbonate and 600g of sodium carbonate, mix them evenly, heat to 600 degrees Celsius, and after melting, stir evenly, let stand and keep warm for 4 hours, and after cooling, obtain molten electrolyte of molten carbonate, then crush and grind into powder.

[0126] The electrolyte membrane is a PN-type composite material, specifically, the PN-type composite material is Ni. 0.3 Zn 0.7 O and 20wt% sodium carbonate.

[0127] The anode material is CuO 1-x And PN-type composite materials, where PN-type composite materials are Ni 0.3 Zn 0.7 O and 20wt% sodium carbonate, CuO 1-x The mass ratio of CuO to PN-type composite materials is 1:0.3-1:0.7. 1-xThe preparation method can be found in the following exemplary steps: Weigh copper oxide, heat it to 1050-1100 degrees Celsius and hold it at that temperature for 2 hours, during which argon gas is introduced to deoxidize it. After cooling, copper oxide CuO containing oxygen vacancies is obtained. 1-x Porous cathodes or partially porous cathodes can be manufactured according to requirements.

[0128] The preparation method of the PN-type composite material can be carried out by solid-state synthesis, as illustrated in the following exemplary steps: Selected P-type and N-type semiconductor oxides are weighed separately according to a designed ratio of 1:2.53, then ground uniformly, sintered at 900 degrees Celsius, cooled, and ground into powder to obtain a PN semiconductor oxide mixture. Based on the PN semiconductor oxide mixture, 20 wt% sodium carbonate is used as the salt additive. The PN semiconductor oxide mixture and salt additive are stirred uniformly, pressed into a sheet, and sintered to form the PN-type composite material. The conductivity, measured using an electrochemical workstation, is between 50 mS / cm and 95 mS / cm at 550 degrees Celsius.

[0129] Electrolysis process: Current density 120 mA / cm², electrode area 4 cm², continuous flow of 2.24 L of carbon monoxide at a flow rate of 0.2 L / h. Initially, electrolysis was performed at 1.28 volts for 2-3 hours to remove moisture. Then, carbon monoxide was introduced at 1.50 volts for electrolysis, maintaining the electrolysis temperature at 550°C and the current density at 120 mA / cm². After 11 hours of reaction, carbon was collected from the surface of the molten electrolyte cathode and from the liquid-liquid interface, yielding a total of 0.96 g of carbon product. The current efficiency was 80.0%.

[0130] Experimental Example 2: Calcium Carbonate Electrolysis Carbon Production System

[0131] The cathode material is made of metallic zinc, with a melting point of 419 degrees Celsius.

[0132] The molten electrolyte is a chloride molten salt, in which the molar ratio of sodium chloride to calcium chloride is 1:1, and the melting point of the chloride molten salt is 505 degrees Celsius.

[0133] The electrolyte membrane is a solid electrolyte La. 0.19 Sr 0.01 Ce 0.8 O2, or La 0.19 Sr 0.01 Ce 0.8 O2 and 20wt% sodium chloride.

[0134] Anode material: La 0.1 Sr 0.4 Ca 0.5 MnO3.

[0135] The electrolyte membrane can be prepared by co-precipitation or sol-gel method. The sol-gel method can be illustrated by the following steps: The precursors are cerium nitrate, strontium nitrate, and lanthanum nitrate. The precursors are weighed according to the molar ratio and dissolved separately in deionized water, then mixed thoroughly. An appropriate amount of precipitant citric acid is added to the solution, and the mixture is stirred and sonicated in a 70°C water bath. The mixture is then stirred again in a 70°C water bath until a colloid is formed. The membrane is then vacuum dried at 105°C for 12 hours, calcined at 600°C for 2 hours at a heating rate of 10°C per minute, cooled, and pulverized to obtain oxide-doped cerium dioxide (La). 0.19 Sr 0.01 Ce 0.8 O2. 20% sodium chloride was added to oxide-doped cerium dioxide, mixed thoroughly, ground, pressed into tablets, and sintered at 900 degrees Celsius to obtain La. 0.19 Sr 0.01 Ce 0.8 Cerium dioxide doped with O2 and 20wt% sodium chloride. Porous or partially porous cathodes can be manufactured as needed.

[0136] La 0.1 Sr 0.4 Ca 0.5 MnO3 can be prepared using the citric acid sol-gel method, as illustrated below: The precursors are lanthanum nitrate, strontium nitrate, calcium nitrate, and manganese nitrate (divalent manganese ions). The precursors are weighed according to the molar ratio and dissolved separately in deionized water, then mixed thoroughly. A suitable amount of 0.375 mol of citric acid as a precipitant is added, and the mixture is stirred and sonicated in a 70°C water bath. The mixture is then stirred again in a 70°C water bath until a colloid is formed. Finally, it is vacuum dried at 105°C for 12 hours and calcined at 800°C for 4 hours at a heating rate of 5°C per minute to obtain La. 0.1 Sr 0.4 Ca 0.5 MnO3 can be used to manufacture porous or partially porous cathodes as needed.

[0137] Electrolysis process: Current density 250 mA / cm², electrode area 4 cm², calcium carbonate addition 10 g. Initially, electrolysis was performed at 1.28 volts for 2-3 hours to remove moisture. The electrolysis temperature was maintained at 550°C, current density 250 mA / cm², voltage 2.0 volts, and the reaction was completed after 11 hours. Carbon on the surface of the molten electrolyte cathode and at the liquid-liquid interface were collected, yielding a total of 0.81 g of carbon product, with a current efficiency of 67.5%.

[0138] Experimental Example 3: Carbon Dioxide Electrolysis Carbon Production System

[0139] The cathode is made of Sn91Zn9 alloy with a melting point of 198 degrees Celsius.

[0140] The molten electrolyte is a chloride molten salt, in which the molar ratio of sodium chloride to calcium chloride is 1:1, and the melting point of the chloride molten salt is 505 degrees Celsius.

[0141] Anode material: MnO 2-x And cerium dioxide doped materials, MnO 2-x The mass ratio of cerium dioxide doped material to cerium dioxide is 1:0.3-1:0.7, and the cerium dioxide doped material includes La. 0.19 Sr 0.01 Ce 0.8 O2, preferably MnO 2-x The mass ratio of MnO to cerium dioxide doped material is 1:0.5. 2-x The preparation method can be found in the following exemplary steps: manganese dioxide is heated at 600-900 degrees Celsius for 2-4 hours under argon protection to partially deoxidize and obtain MnO. 2-x MnO 2-x It is mixed evenly with cerium dioxide doped material and then pressed into tablets. Porous cathodes or partially porous cathodes can be manufactured according to requirements.

[0142] The current density was 250 mA / cm², the electrode area was 4 cm², and 2.24 L of carbon dioxide was continuously introduced at a flow rate of 0.2 L / h. Initially, electrolysis was performed at 1.28 volts for 2-3 hours to remove moisture. The electrolysis temperature was maintained at 550°C, the current density was 250 mA / cm², the voltage was 1.70 volts, and carbon dioxide was introduced for electrolysis. After 11 hours, carbon on the surface of the molten electrolyte cathode and at the liquid-liquid interface were collected, yielding a total of 0.90 g of carbon product. The current efficiency was 75.0%.

[0143] The electrolysis data for carbon production from Experiments 1, 2, and 3 are shown in the table below.

[0144]

[0145] Throughout this specification, references to "an example," "an embodiment," or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment. Therefore, the appearance of "an example," "an embodiment," or "an embodiment" in various places throughout this specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0146] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An electrolytic carbon production system, characterized by, The electrolytic carbon production system comprises an electrolytic cell, an anode, a cathode, a molten electrolyte and an electrolyte film arranged in the electrolytic cell, the electrolytic cell is provided with the molten electrolyte, the electrolyte film is arranged in the molten electrolyte and divides the molten electrolyte into an electrolyte cathode part and an electrolyte anode part, the cathode is arranged in the electrolyte cathode part, and the anode is arranged in the electrolyte anode part; The electrolytic carbon production system further comprises a gas inlet pipe and / or a feed pipe, the outlet of the gas inlet pipe and / or the feed pipe is close to the cathode, carbon dioxide and / or carbon monoxide enter the electrolytic cell through the gas inlet pipe, and carbon generated by electrochemical reduction of the carbon dioxide and / or the carbon monoxide is enriched in the cathode, and carbonate enters the electrolytic cell through the feed pipe, and carbon generated by electrochemical reduction of the carbonate is enriched in the cathode.

2. The electrolytic carbon production system of claim 1, wherein The material of the cathode is selected from at least one of the following: (1) at least one of tin, zinc, bismuth, aluminum, magnesium, gallium and indium; (2) an alloy composed of two or more of tin, zinc, bismuth, aluminum, magnesium, gallium and indium; (3) at least one metal oxide of tin, zinc, bismuth, aluminum, magnesium, gallium and indium.

3. The electrolytic carbon production system of claim 2, wherein, The cathode is a liquid cathode, the electrolyte cathode part is arranged above the liquid cathode, a liquid-liquid interface is formed between the electrolyte cathode part and the liquid cathode, and carbon is generated at the liquid-liquid interface by electrochemical reduction and then floats on the liquid surface of the electrolyte cathode part.

4. The electrolytic carbon production system of claim 1, wherein, When the electrolytic carbon production system produces carbon by electrolysis, the working voltage of the electrolytic carbon production system is 1-2 V.

5. The electrolytic carbon production system of claim 2, wherein, When the material of the cathode comprises at least one metal oxide of tin, zinc, bismuth, aluminum, magnesium, gallium and indium, a reduction voltage is applied to the cathode before electrolytic carbon production to reduce the metal oxide in the cathode to metal, and the reduction voltage of the electrolytic carbon production system is 1.5-5 V.

6. The electrolytic carbon production system of claim 1, wherein, The material of the anode comprises a first component, the first component being one or more of a metal oxide with oxygen defects, or a perovskite oxide; the metal oxide with oxygen defects comprising one or more of tin oxide SnO 2-X , zirconium oxide ZrO 2-X , titanium oxide TiO 2-x , cerium oxide CeO 2-X , silicon oxide SiO 2-x , bismuth oxide Bi2O 3-x , manganese oxide MnO 2-x , copper oxide CuO 1-x , iron oxide Fe2O 3-x , nickel oxide Ni2O 3-x , cobalt oxide Co2O 3-x , wherein x = 0.001-1; the perovskite oxide comprising at least one of LaMO3, La 1-x Ca x MO3, La 1-x Sr x MO3, and La 0.1 Sr 0.9-x Ca x MO3, wherein M is selected from at least one of Mn, Fe, Ni, Co, Cu, and x = 0.1-0.

9.

7. The electrolytic carbon production system of claim 6, wherein The material of the anode further comprises a second component, and the mass ratio of the first component to the second component is 1:0.2-1:5; The second component comprises a cerium dioxide doped material or a PN type composite material; The cerium dioxide doped material comprises an oxide doped cerium dioxide, and the oxide in the oxide doped cerium dioxide is selected from at least one of lanthanum oxide, samarium oxide, gadolinium oxide, magnesium oxide, calcium oxide and strontium oxide, and the molar ratio of the oxide to the oxide doped cerium dioxide is 5%-20%, ​ The PN type composite material comprises a PN semiconductor oxide mixture, the PN semiconductor oxide mixture comprises a P type semiconductor oxide and an N type semiconductor oxide, the mass ratio of the P type semiconductor oxide and the N type semiconductor oxide is 1:0.1-1:10, the P type semiconductor oxide comprises at least one of nickel monoxide, iron monoxide, copper monoxide, tin monoxide, manganese monoxide, cerium sesquioxide and cobalt sesquioxide, and the N type semiconductor oxide comprises at least one of nickel sesquioxide, iron sesquioxide, cobalt sesquioxide, copper oxide, manganese dioxide, tin dioxide, titanium dioxide, silicon dioxide, zinc oxide, gallium sesquioxide and aluminum sesquioxide.

8. The electrolytic carbon production system according to claim 7, wherein, The cerium dioxide doped material comprises the oxide doped cerium dioxide and a salt additive, the mass ratio of the salt additive to the cerium dioxide doped material is 10-30wt%, or The PN type composite material comprises the PN semiconductor oxide mixture and a salt additive, the mass ratio of the salt additive to the PN type composite material is 10-30wt%; wherein The salt additive comprises at least one of sodium carbonate, potassium carbonate, lithium carbonate, sodium chloride, potassium chloride, calcium chloride, lithium sulfate, sodium sulfate and lithium sodium sulfate.

9. The electrolytic carbon production system of claim 1, wherein, The electrolyte anode part is arranged between the anode and the electrolyte membrane, the anode comprises a first surface in contact with the electrolyte anode part, a second surface in contact with air, and an intermediate part arranged between the first surface and the second surface, the first surface is a dense structure, and the second surface and at least part of the intermediate part are porous structures.

10. The electrolytic carbon production system of claim 1, wherein, The anode is entirely a porous structure, and the porosity of the anode is 30%-60%.

11. The electrolytic carbon production system of claim 1, wherein, The molten electrolyte comprises a carbonate, or a chloride, or a sulfate; wherein The carbonate comprises sodium carbonate, or potassium carbonate, or lithium carbonate, or a mixed molten salt of lithium carbonate and sodium carbonate, or a mixed molten salt of lithium carbonate and potassium carbonate, or a mixed molten salt of sodium carbonate and potassium carbonate, or a ternary mixed molten salt of lithium carbonate, sodium carbonate and potassium carbonate; The chloride comprises a first type of chloride, or a composite of the first type of chloride and a second type of chloride; when the chloride molten salt comprises the first type of chloride, the first type of chloride is calcium chloride, or magnesium chloride, or lithium chloride; when the chloride molten salt comprises the composite of the first type of chloride and the second type of chloride, the first type of chloride is one or two of calcium chloride, magnesium chloride and lithium chloride, and the second type of chloride is sodium chloride and / or potassium chloride; The sulfate comprises lithium sulfate, or a mixed molten salt of sodium sulfate and lithium sulfate, or a mixed molten salt of lithium sulfate and potassium sulfate, or a ternary molten salt of lithium sulfate, sodium sulfate and potassium sulfate.

12. The electrolytic carbon production system of claim 1, wherein, The material of the electrolyte membrane comprises a cerium dioxide doped material or a PN type composite material; wherein The cerium dioxide doped material comprises oxide doped cerium dioxide, and the oxide in the oxide doped cerium dioxide is at least one selected from lanthanum oxide, samarium oxide, gadolinium oxide, magnesium oxide, calcium oxide and strontium oxide, and the molar ratio of the oxide to the oxide doped cerium dioxide is 5%-20%, The PN type composite material comprises a PN semiconductor oxide mixture, the PN semiconductor oxide mixture comprises a P type semiconductor oxide and an N type semiconductor oxide, the mass ratio of the P type semiconductor oxide to the N type semiconductor oxide is 1:0.1-1:10, the P type semiconductor oxide comprises at least one of nickel monoxide, iron monoxide, copper monoxide, tin monoxide, manganese monoxide, cerium sesquioxide and cobalt trioxide, and the N type semiconductor oxide comprises at least one of nickel sesquioxide, iron sesquioxide, cobalt sesquioxide, copper oxide, manganese dioxide, tin dioxide, titanium dioxide, silicon dioxide, zinc oxide, gallium sesquioxide and aluminum sesquioxide.

13. The electrolytic carbon production system according to claim 9, wherein The cerium dioxide doped material comprises the oxide doped cerium dioxide and a salt additive, and the mass ratio of the salt additive to the cerium dioxide doped material is 10-30wt%, or The PN type composite material comprises the PN semiconductor oxide mixture and a salt additive, and the mass ratio of the salt additive to the PN type composite material is 10-30wt%; wherein The salt additive comprises at least one of sodium carbonate, potassium carbonate, lithium carbonate, sodium chloride, potassium chloride, calcium chloride, lithium sulfate, sodium sulfate and lithium sodium sulfate.

14. The electrolytic carbon production system of claim 1, wherein, The working temperature of the electrolytic carbon production system is 350-700 degrees Celsius.

15. The electrolytic carbon production system of claim 1, wherein, The electrolytic carbon production system further comprises a carbon fixation oxide collecting device, when the feed pipe is connected to the carbonate, the carbonate is further converted into alkali metal oxide and / or alkaline earth metal oxide by electrochemical reduction treatment, the alkali metal oxide and / or the alkaline earth metal oxide absorbs carbon dioxide, or the alkali metal oxide and / or the alkaline earth metal oxide absorbs carbon dioxide after being dissolved in water.

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