High-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor as well as preparation method and application thereof

Abstract

The invention relates to a high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor as well as a preparation method and application thereof. The high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor comprises a porous structure fuel electrode support body for supporting the strength of the electrochemical reactor; the catalyst particles are loaded in the porous structure of the fuel electrode support body; the electrolyte layer is arranged on the upper part or the outer side of the fuel electrode support body; the air electrode layer is arranged on the upper part or the outer side of the electrolyte layer.

Description

Technical Field

[0001] The present invention belongs to renewable energy and CO 2 The technical field of recycling is particularly related to a high-stability proton conductor type CO 2 In-situ hydrogenation electrochemical reactor and preparation method and application thereof. Background Art

[0002] Large amounts of CO 2 Global warming caused by CO emissions has become an environmental issue of global concern. 2 As a carbon source and green hydrogen to convert into CO, CH 4 , CH 3 OH and other high value-added fuels and chemical products, is also a very promising way of carbon conversion.

[0003] Proton Conducting Solid Oxide Electrolysis Cell (PC-SOEC) is a device that uses protons as carriers to achieve efficient conversion of electrical energy and chemical energy at medium and high temperatures (400-700°C). Water is electrolyzed on the air electrode side (Formula 1), and protons migrate to the fuel electrode to generate H 2 (Equation 2); If CO is introduced into the fuel electrode side 2 , CO can be achieved 2 In-situ hydrogenation to generate CO, CH 4 and CH 3 OH and other products (Formula 3-5), high energy efficiency and low power consumption at high temperatures, and CO 2 High activity, CO 2 High conversion rate. H 2 O→2H + +1 / 2O 2 +2e - (1) 2H + +2e - →H 2 (2) CO 2 +H 2 →CO+H 2 O (3) CO 2 +4H 2 →CH 4 +2H 2 O (4) CO 2 +3H 2 →CH 3 OH+H2 O (5)

[0004] At present, there are reports on the use of flat-plate and tubular proton conductor solid oxide electrolyzers to electrolyze water to produce hydrogen and react with CO 2 In-situ reaction method, but the proton conductor materials used are all perovskite-type (ABO 3 ) metal oxides. Ba-based perovskite materials have high electrical conductivity, but their 2 BaCO will be produced in the atmosphere 3 , which damages the structure of the electrolytic cell, thus showing extremely poor performance against CO 2 Stability is a serious drawback that hinders the application of proton conductor solid oxide electrolyzers in catalyzing CO 2 Practical applications in the field of hydroconversion. Summary of the invention

[0005] In view of the above technical problems, the present invention aims to provide a 2 CO with high stability 2 Electrochemical reactor for in-situ hydrogenation conversion and preparation method thereof, so as to efficiently and stably catalyze CO 2 In situ hydroconversion.

[0006] In the first aspect, the present invention provides a high stability proton conductor type CO 2 In-situ hydrogenation electrochemical reactor, the high stability proton conductor type CO 2 The in-situ hydrogenation electrochemical reactor includes: A porous structure fuel electrode support that supports the strength of the electrochemical reactor; Catalyst particles supported within the porous structure of the fuel electrode support; an electrolyte layer disposed on the upper part or the outer side of the fuel electrode support; and The air electrode layer is disposed on the upper part or outside of the electrolyte layer.

[0007] Preferably, the material of the fuel electrode support is 2 La-based electron conductor material with high stability; preferably, the material of the fuel electrode support includes La a (W 1-b Mo b ) 1-c M c O 12-δ (5.2≤a≤5.8, 0≤b≤0.4, 0≤c≤0.05, 0≤δ≤1, M includes Ni, Cu, Pd, Fe), La 1-x Sr x M 1-a M' a O3-δ (0≤x≤0.3, 0≤a≤0.1, 0≤δ≤0.2, M includes Y, Yb, In, Sc, M' includes Ni, Cu, Pd, Fe), La 2-x M x Ce 2-a M' a O 7-δ (0≤x≤0.3, 0≤a≤0.2, 0≤δ≤0.35, M includes Mg, Ca, Ba, M' includes Ni, Cu, Pd, Fe), La 2-x M x Zr 2-a M' a O 7-δ (0≤x≤0.3, 0≤a≤0.2, 0≤δ≤0.35, M includes Mg, Ca, Ba, M' includes Ni, Cu, Pd, Fe) and La 1-x M x Nb 1-a M' a O 4 (0≤x≤0.3, 0≤a≤0.1, M includes Mg, Ca, Sr, Ba, Yb, M' includes Ni, Cu, Pd, Fe) at least one; more preferably, the material of the fuel electrode support is La 5.4 (W 0.6 Mo 0.4 ) 0.95 Ni 0.05 O 12-δ ; The thickness of the fuel electrode support is 0.5-1 mm, and the porosity is 40-50%.

[0008] Preferably, the catalyst particles include Ni, Cu, Fe, Co, Gd 0.2 Ce 0.8 O 2-δ (GDC), Sm 0.2 Ce 0.8 O 2-δ (SDC), Er 0.4 Bi 1.6 O 3 At least one of (ESB); The content of the catalyst particles is 30-60wt% of the total mass of the fuel electrode support and the catalyst, and the particle size is 30-60nm.

[0009] Preferably, the material of the electrolyte layer is 2 La-based electron conductor material with high stability; preferably, the material of the electrolyte layer includes La a M b WO12-δ (5.2≤a≤5.8, 0≤b≤0.2, 0≤δ≤2, M includes Bi, K), La 1-x Sr x MO 3-δ (0≤x≤0.3, 0≤δ≤0.2, M includes Y, Yb, In, Sc), La 2-x M x Ce 2 O 7-δ (0≤x≤0.3, 0≤δ≤0.35, M includes Mg, Ca, Ba), La 2-x M x Zr 2 O 7-δ (0.1≤x≤0.3, 0≤δ≤0.35, M includes Mg, Ca, Ba) and La 1- x M x NbO 4 (0≤x≤0.3, M includes at least one of Mg, Ca, Sr, Ba, Yb); more preferably, the material of the electrolyte layer is La 5.5 Bi 0.1 WO 11.4 ; The thickness of the electrolyte layer is 5-20 μm.

[0010] Preferably, the material of the air electrode layer includes Bi 2-x Er x O 3 (ESB, 0≤x≤0.5), La 1-x Sr x MnO 3-δ (LSM,0≤x≤0.5,0≤δ≤0.25), La 2-x Sr x NiO 4 (LSN, 0≤x≤1), La 1-x Sr x Cr 0.5 Mn 0.5 O 3-δ (LSCM, 0≤x≤0.5, 0≤δ≤0.25) at least one; preferably Bi 1.6 Er 0.4 O 3 -La 0.8 Sr 0.2 MnO 3-δ ; The thickness of the air electrode layer is 10 to 40 μm, preferably 10 to 20 μm.

[0011] In a second aspect, the present invention provides a high stability proton conductor type CO 2 A method for preparing an in-situ hydrogenation electrochemical reactor, the preparation method comprising the following steps: (1) mixing the material powder of the fuel electrode support with a pore-forming agent and forming the mixture into a green body, and performing a first sintering to obtain a porous structure fuel electrode support; (2) attaching the material of the electrolyte layer to the surface of the porous structure fuel electrode support, and performing a second sintering to obtain an electrolyte layer-porous structure fuel electrode support structure; (3) attaching the air electrode material to the surface of the electrolyte layer and sintering for the third time to obtain an air electrode layer-electrolyte layer-porous fuel electrode support structure; (4) impregnating a catalyst solution into the porous fuel electrode support of the air electrode layer-electrolyte layer-porous structure fuel electrode support structure, and sintering for the fourth time to obtain an air electrode layer-electrolyte layer-catalyst / porous structure fuel electrode support structure; (5) installing auxiliary components and sealing the air electrode layer-electrolyte layer-catalyst / porous fuel electrode support structure to obtain the high-stability proton conductor type CO 2 In situ hydrogenation electrochemical reactor.

[0012] Preferably, in step (1), the temperature of the first sintering is 1100-1300° C., and the time is 1-4 hours; In step (2), the second sintering is carried out at a temperature of 1300 to 1500° C. and for a time of 2 to 5 hours; In step (3), the temperature of the third sintering is 800-1000° C. and the time is 1-4 hours; In step (4), the temperature of the fourth sintering is 300-700° C., and the time is 1-3 hours.

[0013] In a third aspect, the present invention provides a high stability proton conductor type CO 2 In-situ hydrogenation electrochemical reactors utilize CO 2 In-situ hydrogenation to produce CO and CH 4 or CH 3 OH.

[0014] Preferably, the application method comprises the following steps: (1) H 2 The high stability proton conductor type CO is introduced 2 The fuel electrode of the in-situ hydrogenation electrochemical reactor reduces the catalyst material while dissolving metal nanoparticles from the fuel electrode support in-situ to alloy with the catalyst; (2) Switch the gas flowing into the fuel electrode to CO 2 , pass humid air into the air electrode side and apply electricity to react, then CO 2 In-situ hydrogenation conversion to produce CO and CH 4 , CH 3 At least one of OH.

[0015] Beneficial Effects 1. The present invention has a simple structure and only requires a small amount of wet air and CO during the reaction. 2 , it is possible to electrolyze water and CO in one device 2 Hydrogenation, humid air and CO 2 The hydrogenation products are in different chambers, which is conducive to product separation; by regulating the sintering activity of the material, a porous structure of the fuel electrode support and a dense electrolyte layer is achieved, and the catalysts of the fuel electrode are all introduced by a solution impregnation method, avoiding the side reactions caused by high-temperature co-firing and making it easier to adjust the catalyst; and the support material is pre-doped with transition metal elements, and metal nanoparticles are dissolved in a reducing atmosphere to alloy with the catalyst to anchor the catalyst and inhibit the sintering of the nanocatalyst; the present invention uses La-based electron conductor materials, which are more effective for CO compared with traditional Ba-based electron conductor materials. 2 The chemical stability is better and can meet the long-term stability requirements in actual industrial atmosphere; 2. Compared with the traditional proton conductor oxide electrolyzer electrocatalyzed CO 2 The hydrogenation process of the present invention has the following advantages: (1) High chemical stability: Due to the use of CO 2 The La-based electron conductor material with high stability replaces the traditional Ba-based electron conductor material and will not react with CO at the working temperature. 2 The reaction produces carbonates, which have higher long-term stability; (2) Flexible catalyst regulation: All catalysts are introduced by impregnation, and the components and proportions of the catalysts can be flexibly adjusted, thereby improving the stability and catalytic activity of the catalysts; (3) High catalytic performance: All catalysts in the present invention are nano-scale particles, which have higher catalytic performance than traditional proton conductor oxide electrolytic cells; (4) Good catalyst stability: Nanoparticles are dissolved in situ from the support and alloyed with catalyst particles, thereby enhancing the interaction between the catalyst and the support and inhibiting the sintering of nano-scale catalysts at high temperatures. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The high stability proton conductor type CO exemplified by the present invention 2 Schematic diagram of the structure of an in-situ hydrogenation electrochemical reactor; wherein (a) is a schematic diagram of the structure of a flat-plate electrochemical reactor, and (b) is a schematic diagram of the structure of a tubular electrochemical reactor; Figure 2The fuel electrode support described in Example 1 is heated at 600°C and H 2 SEM image after treatment in atmosphere for 5 h; Figure 3 The gas chromatography analysis result of the tail gas on the fuel electrode side when the electrochemical synthesizer described in Example 1 is operated at 500° C.; Figure 4 The Raman spectra of the electrochemical synthesizer in Example 1 before and after operation; Reference numerals: 1- fuel electrode support; 2- electrolyte layer; 3- air electrode layer; 4- catalyst; 5- alumina tube; 6- quartz tube. DETAILED DESCRIPTION

[0017] The present invention is further described below by the following embodiments. It should be understood that the following embodiments are only used to illustrate the present invention, but not to limit the present invention.

[0018] First, if Figure 1 As shown, the present invention provides a method for producing hydrogen and CO by electrolysis of water 2 High-stability proton conductor type CO with integrated hydrogenation and conversion 2 In-situ hydrogenation electrochemical reactor. Wherein, the high stability proton conductor type CO 2 In situ hydrogenation electrochemical reactors may include: A porous fuel electrode support 1 that supports the strength of the electrochemical reactor; Catalyst particles 4 supported inside the porous structure of the fuel electrode support 1; An electrolyte layer 2 disposed on the upper part or the outer side of the fuel electrode support 1; and The air electrode layer 3 is disposed on the upper part or outside of the electrolyte layer 2 .

[0019] The high stability proton conductor type CO provided by the present invention 2 The in-situ hydrogenation electrochemical reactor is based on a tubular or flat fuel electrode supported PC-SOEC, which can use renewable electricity to directly react the hydrogen produced by water vapor electrolysis with CO on the fuel electrode side. 2 The reaction produces high value-added chemical products.

[0020] In some embodiments, the material of the fuel electrode support may be 2 La-based electron conductor material with high stability; preferably, the material of the fuel electrode support may include La a (W 1-b Mo b ) 1-c M c O 12-δ(5.2≤a≤5.8, 0≤b≤0.4, 0≤c≤0.05, 0≤δ≤1, M includes Ni, Cu, Pd, Fe), La 1-x Sr x M 1-a M' a O 3-δ (0≤x≤0.3, 0≤a≤0.1, 0≤δ≤0.2, M includes Y, Yb, In, Sc, M' includes Ni, Cu, Pd, Fe), La 2-x M x Ce 2-a M' a O 7-δ (0≤x≤0.3, 0≤a≤0.2, 0≤δ≤0.35, M includes Mg, Ca, Ba, M' includes Ni, Cu, Pd, Fe), La 2-x M x Zr 2-a M' a O 7-δ (0≤x≤0.3, 0≤a≤0.2, 0≤δ≤0.35, M includes Mg, Ca, Ba, M' includes Ni, Cu, Pd, Fe) and La 1- x M x Nb 1-a M' a O 4 (0≤x≤0.3, 0≤a≤0.1, M includes Mg, Ca, Sr, Ba, Yb, M' includes Ni, Cu, Pd, Fe) at least one; more preferably, the material of the fuel electrode support is La 5.4 (W 0.6 Mo 0.4 ) 0.95 Ni 0.05 O 12-δ .

[0021] The material of the fuel electrode support body used in the present invention is doped with transition metals, and the support body can dissolve metal nanoparticles in situ under a reducing atmosphere, thereby alloying with catalyst particles, anchoring the catalyst particles, and inhibiting the sintering of the catalyst particles.

[0022] In some embodiments, the thickness of the fuel electrode support can be 0.5-1 mm, and the porosity can be 40-50%. If the thickness is too large, the metal catalyst is difficult to be impregnated into the electrolyte layer, reducing the electrochemical performance; if the thickness is too small, the strength of the support is too low, which is not conducive to the long-term operation of the converter.

[0023] In some embodiments, the catalyst particles may include metals such as Ni, Cu, Fe, Co, or Gd 0.2 Ce0.8 O 2-δ (GDC), Sm 0.2 Ce 0.8 O 2-δ (SDC), Er 0.4 Bi 1.6 O 3 The catalyst is located in the porous structure of the fuel electrode support and is mainly used to provide electronic conductivity of the fuel electrode and catalyze CO 2 Reacts with hydrogen.

[0024] When the converter is started, the H 2 The metal oxides (such as NiO, CuO, etc.) obtained by impregnation with nitrate and calcination will be reduced to metal catalysts. Different metal catalysts can be selected according to the target product. The target product is CH 4 When Ni is used as a catalyst, oxides rich in oxygen vacancies such as SDC can 2 It has a strong adsorption effect and can effectively enhance CO 2 conversion rate.

[0025] In some embodiments, the content of the catalyst particles can be 30-60wt% of the total mass of the fuel electrode support and the catalyst; the particle size can be 30-60nm. If the catalyst content is too low, there will be insufficient active sites, poor catalytic effect, and it will be difficult for the metal catalyst particles to form a continuous conductive path; if the catalyst content is too high, the pores of the fuel electrode support will be blocked, which is not conducive to gas diffusion.

[0026] Unlike conventional PC-SOEC, which uses Ba-containing perovskite electrolyte materials, in some embodiments, the material of the electrolyte layer can be CO 2 La-based electron conductor materials with high stability to improve the catalytic CO conversion of converters 2 Preferably, the material of the electrolyte layer may include La a M b WO 12-δ (5.2≤a≤5.8, 0≤b≤0.2, 0≤δ≤2, M includes Bi, K), La 1-x Sr x MO 3-δ (0≤x≤0.3, 0≤δ≤0.2, M includes Y, Yb, In, Sc), La 2- x M x Ce 2 O 7-δ (0≤x≤0.3, 0≤δ≤0.35, M includes Mg, Ca, Ba), La 2-xM x Zr 2 O 7-δ (0.1≤x≤0.3, 0≤δ≤0.35, M includes Mg, Ca, Ba) and La 1-x M x NbO 4 (0≤x≤0.3, M includes at least one of Mg, Ca, Sr, Ba, Yb); more preferably, the material of the electrolyte layer is La with high sintering activity 5.5 Bi 0.1 WO 11.4 The electrolyte layer is made of La-based proton conductor material, located in the middle layer of the electrochemical device, and is mainly used for conducting protons.

[0027] In some embodiments, the thickness of the electrolyte layer may be 5-20 μm. If the thickness of the electrolyte layer is too large, the impedance is large and the electrochemical performance of the converter is poor; if the thickness of the electrolyte layer is too small, leakage is likely to occur.

[0028] In some embodiments, the material of the air electrode layer may include Bi 2-x Er x O 3 (ESB, 0≤x≤0.5), La 1-x Sr x MnO 3-δ (LSM,0≤x≤0.5,0≤δ≤0.25), La 2-x Sr x NiO 4 (LSN, 0≤x≤1), La 1- x Sr x Cr 0.5 Mn 0.5 O 3-δ (LSCM, 0≤x≤0.5, 0≤δ≤0.25) at least one; preferably Bi 1.6 Er 0.4 O 3 -La 0.8 Sr 0.2 MnO 3-δ La-based electrolyte materials tend to easily undergo side reactions with Co-containing air electrode materials, so in the present invention, it is necessary to select an air electrode material that does not contain Co.

[0029] The air electrode layer is located at the outermost side of the electrochemical device and is mainly used to connect the positive electrode of the battery and the generation of protons. Water vapor is decomposed into protons and oxygen here.

[0030] In some embodiments, the thickness of the air electrode layer may be 10 to 40 μm, preferably 10 to 20 μm. If the thickness of the air electrode layer is too large, gas diffusion is difficult, which will increase the polarization impedance of the converter; if the thickness of the air electrode layer is too small, there are too few active sites for the electrolysis of water, which will also increase the polarization impedance of the converter.

[0031] In some embodiments, the electrolyte layer can be controlled to completely cover the surface of the fuel electrode support; the area of ​​the air electrode layer is smaller than the area of ​​the electrolyte layer.

[0032] The electrochemical reactor provided by the present invention utilizes electric energy to efficiently electrolyze water vapor to produce dry pure hydrogen and CO 2 Electrochemical reactors for in-situ reaction to produce high value-added fuels and chemicals. Specifically, the electrochemical properties of proton conductor materials are used to electrolyze water vapor at the air electrode and generate hydrogen at the fuel electrode. The hydrogen reacts with CO introduced into the fuel electrode. 2 Reaction, in situ production of CO, CH 4 The electrochemical reactor is mainly based on a proton conductor solid oxide electrolysis cell supported by a tubular or flat fuel electrode. In the present invention, CO 2 La-based electron conductors with higher stability replace traditional Ba-based electron conductors, achieving higher long-term stability of the reactor.

[0033] The following is an exemplary description of the high stability proton conductor type CO provided by the present invention. 2 A method for preparing an in-situ hydrogenation electrochemical reactor. The method may include the following steps: (1) mixing the material powder of the fuel electrode support with a pore-forming agent and forming the mixture into a green body, and performing a first sintering to obtain a porous structure fuel electrode support; (2) attaching the material of the electrolyte layer to the surface of the porous structure fuel electrode support, and performing a second sintering to obtain an electrolyte layer-porous structure fuel electrode support structure; (3) attaching the air electrode material to the surface of the electrolyte layer and sintering for the third time to obtain an air electrode layer-electrolyte layer-porous fuel electrode support structure; (4) impregnating a catalyst solution into the porous fuel electrode support of the air electrode layer-electrolyte layer-porous structure fuel electrode support structure, and sintering for the fourth time to obtain an air electrode layer-electrolyte layer-catalyst / porous structure fuel electrode support structure; (5) installing auxiliary components and sealing the air electrode layer-electrolyte layer-catalyst / porous fuel electrode support structure to obtain the high-stability proton conductor type CO 2 In situ hydrogenation electrochemical reactor.

[0034] In some embodiments, in step (1), the material powder of the fuel electrode support can be synthesized by a solid phase reaction method; preferably, the material powder of the fuel electrode support can be subjected to a calcination and coarsening treatment before being mixed with the pore-forming agent to reduce the sintering activity, thereby increasing the porosity of the fuel electrode support, and the calcination and coarsening temperature can be 1200-1300°C, and the time can be 5-10h.

[0035] Among them, the support powder obtained by calcination needs to pass through a 200-mesh steel sieve, and the particle size can be 2 to 5 μm. If the calcination temperature is too high or the time is too long, the sintering activity of the support will be too poor, making it difficult to drive the electrolyte layer to shrink and reduce the density of the electrolyte layer; if the calcination temperature is too low or the time is too short, the sintering activity of the support will be high, and the porosity of the converter support will be low, which is not conducive to impregnation.

[0036] In some embodiments, in step (1), the pore former may include at least one of starch, polymethyl methacrylate (PMMA), carbon microspheres, and graphite, preferably polymethyl methacrylate; the content of the pore former may be 30-50wt% of the material powder mass of the fuel electrode support, preferably 50wt%, so that sufficient porosity can be formed in the fuel electrode to ensure the catalyst loading and gas phase transport of the fuel electrode impregnation.

[0037] In some embodiments, in step (1), the forming method can be dry pressing or cold isostatic pressing.

[0038] In some embodiments, in step (1), the temperature of the first sintering may be 1100-1300°C, and the time may be 1-4 hours. If the first sintering temperature is too high or the time is too long, the green blank obtained will shrink too much, reducing the shrinkage rate of the subsequent electrolyte layer; if the first sintering temperature is too low or the time is too short, the green blank strength will be too low, and it will be easy to break when the electrolyte layer is impregnated later.

[0039] In some embodiments, in step (2), the material of the electrolyte layer can be synthesized by a sol-gel method to improve the sintering activity of the powder; preferably, the sintering activity of the electrolyte layer can be improved by pre-doping a sintering aid into the material of the electrolyte layer.

[0040] Take La 5.5 Bi 0.1 WO 11.4 As an example, the process of synthesizing the material of the electrolyte layer by the sol-gel method may include the following steps: La(NO 3 ) 3 6H 2 O. Bi(NO 3) 3 etc. were dissolved in deionized water and WO 3 , add ethylenediaminetetraacetic acid (EDTA) and citric acid monohydrate, wherein the ratio of citric acid monohydrate to metal cation substances is 1.5:1, and the ratio of EDTA to metal cation substances is 1:1; add ammonia water to adjust the pH to 7-8 to ensure sufficient complexation of metal cations; wait for WO 3 After complete dissolution, the solution is dried by water bath heating to form a gel; the gel is transferred to a blast drying oven and dried at 170°C for 10 hours to obtain a dry gel, and then the dry gel is calcined in a muffle furnace to obtain a powder; the calcination temperature is 800-1000°C and the time can be 5-10 hours.

[0041] The sol-gel method can achieve uniform mixing of elements at the molecular level, which is beneficial to reduce the calcination temperature and calcination time required for the synthetic material. Lower calcination temperature and calcination time are beneficial to inhibit the sintering coarsening of the powder and improve the sintering activity of the electrolyte layer.

[0042] In some embodiments, the pre-doped sintering aid may include Li 2 O.B 2 O 3 etc., and the added amount can be 0.5-1wt%.

[0043] In some embodiments, in step (2), the material of the electrolyte layer is attached to the surface of the porous structure fuel electrode support by slurry impregnation, deposition, spraying or spin coating.

[0044] In some embodiments, in step (2), the second sintering temperature may be 1300-1500°C, and the time may be 2-5 hours. If the second sintering temperature is too low or the time is too short, the density of the electrolyte layer is low, and leakage is likely to occur; if the second sintering temperature is too high or the time is too long, the support body shrinks too much, the porosity is low, and it is not conducive to subsequent impregnation.

[0045] In some embodiments, in step (3), the air electrode material is attached to the surface of the electrolyte layer by mixing the air electrode material with a binder to obtain an air electrode slurry which is coated on the surface of the electrolyte layer by dipping, screen printing or spraying.

[0046] In some embodiments, in step (3), the temperature of the third sintering can be 800-1000°C, and the time can be 1-4 hours. When the third sintering temperature is too low, the air electrode and the electrolyte are weakly bonded and easily fall off; when the third sintering temperature is too high or the time is too long, the porosity of the air electrode is low, which is not conducive to gas diffusion and increases the polarization impedance of the converter.

[0047] In some embodiments, in step (4), the catalyst solution may include Ni(NO 3 ) 2 、Cu(NO 3 ) 2 、Co(NO 3 ) 3 、Fe(NO 3 ) 3 、Ce(NO 3 ) 4 、Sm(NO 3 ) 3 , Bi(NO 3 ) 3 、Er(NO 3 ) 3 A solution prepared by at least one of the following.

[0048] It should be noted that the calcination in step (1) obtains a porous support body blank, which has low strength. If the blank is impregnated with a catalyst solution at this time, it will cause the blank to break. In addition, the calcination temperature of step (2) is very high. Performing step (2) after impregnation will cause the calcination temperature of the catalyst to be too high. Therefore, the catalyst cannot be impregnated after step (1) and then step (2) cannot be performed.

[0049] In some embodiments, in step (4), the temperature of the fourth sintering can be 300-700°C, and the time can be 1-3 hours. If the temperature of the fourth sintering is too high or the time is too long, the catalyst particles will be coarsened and side reactions with the fuel electrode support will occur, resulting in a decrease in catalytic performance; if the sintering temperature is too low or the time is too short, the catalyst will not be able to completely form a phase.

[0050] In some embodiments, in step (5), the auxiliary components may include a wire, a current collecting material, an alumina tube, or a quartz tube.

[0051] In summary, the CO provided by the present invention 2The electrochemical synthesizer for in-situ hydrogenation conversion uses La-based proton conductor materials instead of traditional Ba-based proton conductor materials, which improves the long-term stability of the electrochemical synthesizer; and, by regulating the sintering activity of the materials, a porous support and a dense electrolyte layer structure are achieved, and the catalyst material is flexibly adjusted through the solution impregnation method, and the side reactions of the La-based material and the catalyst material at high temperatures are suppressed. At the same time, different elements are doped in the materials of the support layer and the electrolyte layer to achieve different functions; transition metal elements are doped in the support, and metal nanoparticles are dissolved in situ under a reducing atmosphere to alloy with the catalyst, anchor the catalyst, and suppress catalyst sintering; a sintering aid is pre-doped in the electrolyte layer to improve the sintering activity of the electrolyte layer and increase the density of the electrolyte layer. According to the present invention, it is possible to catalyze CO 2 while producing hydrogen by high-temperature electrolysis of water. 2 Conversion, in situ production of CO and CH 4 or CH 3 OH and other products, with the advantages of simple system and high energy efficiency, and the material does not react with CO 2 The occurrence of side reactions can ensure the long-term stable operation of the synthesizer.

[0052] In addition, the present invention also provides a high-stability proton conductor type CO 2 In-situ hydrogenation electrochemical reactors utilize CO 2 In-situ hydrogenation to produce CO and CH 4 or CH 3 Application in OH.

[0053] In some embodiments, the method of application may include the following steps: (1) H 2 The high stability proton conductor type CO is introduced 2 The fuel electrode of the in-situ hydrogenation electrochemical reactor reduces the catalyst material while dissolving metal nanoparticles from the fuel electrode support in-situ to alloy with the catalyst; (2) Switch the gas flowing into the fuel electrode to CO 2 , pass humid air into the air electrode side and apply electricity to react, then CO 2 In-situ hydrogenation conversion to produce CO and CH 4 , CH 3 At least one of OH.

[0054] In some embodiments, in step (2), the temperature for the reaction during power-on can be 400-700°C.

[0055] Specifically, the operating conditions of the electrochemical synthesizer are as follows: (1) the fuel electrode of the electrochemical synthesizer is sealed on the alumina tube using a sealing material (e.g., ceramic glue, glass ceramic) and the wire connected to the fuel electrode is led out, leaving only the gas transmission path connected to the outside; in addition, a wire is led out from the surface of the outer air electrode, and the air electrode and fuel electrode wires are connected to the positive and negative electrodes of the external power supply respectively; (2) the electrochemical synthesizer is heated to the operating temperature (400-700°C) and kept warm, and H is first introduced into the inside of the electrochemical synthesizer. 2 The catalyst particles are reduced, and the support body is in situ dissolved to alloy the metal nanoparticles with the catalyst particles. Then, air containing water vapor is introduced into the outside of the electrochemical synthesizer, and the inside is switched to carrier gas and CO. 2 (3) The inner lead of the electrochemical synthesizer is connected to the negative pole of the external DC power supply, and the outer fuel electrode lead is connected to the positive pole of the external DC power supply. The electrochemical synthesizer operates in the range of 0.2 to 1.0 V higher than the open circuit voltage to achieve CO 2 In situ hydroconversion.

[0056] The electrochemical reactor provided by the present invention has a simple structure, requires only a small amount of water during the reaction, and generates H in situ. 2 With CO 2 The porous-dense double-layer structure can flexibly adjust the catalyst on the fuel electrode side, which is beneficial to CO 2 The catalyst particles are anchored by in-situ alloying to inhibit the sintering of catalyst particles. 2 The advantage of high stability is that it can be used in high concentration CO 2 The conversion is carried out stably and for a long time under the atmosphere, and it has the advantages of cleanness, environmental protection, high conversion rate and high stability.

[0057] The following examples are further listed to illustrate the present invention in detail. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention all belong to the scope of protection of the present invention. The specific process parameters of the following examples are also only examples within a suitable range, that is, those skilled in the art can make selections within a suitable range through the description of this article, and are not limited to the specific values ​​​​exemplified below. If not specifically stated, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0058] Example 1

[0059] The flat-plate high-stability proton conductor type CO 2 Preparation method of in-situ hydrogenation electrochemical reactor and use of the same to convert CO 2 In-situ hydrogenation to produce CO and CH4 or CH 3 The OH process may include the following steps: La was prepared by dry pressing-high temperature sintering-impregnation-sintering process. 5.4 (W 0.6 Mo 0.4 ) 0.95 Ni 0.05 O 12-δ (Fuel electrode support)-La 5.5 Bi 0.1 WO 11.4 The electrolyte layer is a flat plate structure, and Bi is coated and sintered on the surface of the electrolyte layer. 1.6 Er 0.4 O 3 -La 0.8 Sr 0.2 MnO 3-δ The air electrode layer is made by impregnating and calcining the Co catalyst in the fuel electrode support, and using the hydrogen generated by high-temperature electrolysis of water to react with CO 2 The in situ reaction produces CO and methane. Specifically: The fuel electrode support is prepared by dry pressing. The material of the fuel electrode support is La 5.4 (W 0.6 Mo 0.4 ) 0.95 Ni 0.05 O 12-δ After obtaining the support body blank, the support body is obtained after sintering at 1200°C for 1 hour; then La is prepared on the surface of the support body by slurry impregnation method. 5.5 Bi 0.1 WO 11.4 Electrolyte layer (sintered at 1400℃ for 5 hours); Bi 1.6 Er 0.4 O 3 -La 0.8 Sr 0.2 MnO 3-δ Air electrode layer (sintered at 800℃ for 3 hours); finally, Co(NO 3 ) 2 The solution was calcined at 600°C for 1 hour to prepare a catalyst, and auxiliary components were installed and sealed to obtain the high-stability proton conductor type CO 2 In situ hydrogenation electrochemical reactor.

[0060] Figure 2 The fuel electrode support described in Example 1 is heated at 600°C and H 2 SEM image after being treated in atmosphere for 5 hours. It can be seen from the figure that La5.4 (W 0.6 Mo 0.4 ) 0.95 Ni 0.05 O 12-δ Ni metal nanoparticles were dissolved from the surface of the support.

[0061] Figure 3 The gas chromatographic analysis results of the tail gas on the fuel electrode side when the electrochemical synthesizer described in Example 1 is operated at 500°C. As can be seen from the figure, in addition to the CO 2 and H produced by electrolysis 2 In addition, characteristic peaks of CO and methane appeared in the tail gas on the fuel electrode side.

[0062] Figure 4 The Raman spectra of the electrochemical synthesizer in Example 1 before and after operation are shown in the figure. It can be seen from the figure that there is no obvious change in the Raman spectra before and after the operation of the electrochemical synthesizer, and no characteristic peak of carbonate appears, indicating that the material is resistant to CO 2 Has high stability.

[0063] Example 2

[0064] The tubular high-stability proton conductor type CO provided in this embodiment 2 Preparation method of in-situ hydrogenation electrochemical reactor and use of the same to convert CO 2 In-situ hydrogenation to produce CO and CH 4 or CH 3 The OH process may include the following steps: La was prepared by isostatic pressing-high temperature sintering-impregnation-sintering process. 5.4 (W 0.6 Mo 0.4 ) 0.95 Ni 0.05 O 12-δ (Fuel electrode support)-La 5.5 Bi 0.1 WO 11.4 The electrolyte layer is a tubular structure, and Bi is impregnated and sintered on the surface of the electrolyte layer. 1.6 Er 0.4 O 3 -La 0.8 Sr 0.2 MnO 3-δ The air electrode layer is made by impregnating and calcining the Co catalyst in the fuel electrode support, and using the hydrogen generated by high-temperature water electrolysis to react with CO 2 The in situ reaction produces CO and methane. Specifically: The fuel electrode support tube is prepared by isostatic pressing. The material of the fuel electrode support is La5.4 (W 0.6 Mo 0.4 ) 0.95 Ni 0.05 O 12-δ After obtaining the support body blank, a support tube was obtained after sintering at 1200°C for 1 hour. The support tube was 20 cm long, 12 mm in diameter, and 1 mm thick. Then, La was prepared on the outer surface of the support tube by slurry impregnation. 5.5 Bi 0.1 WO 11.4 Electrolyte layer (sintered at 1400℃ for 5 hours) and Bi 1.6 Er 0.4 O 3 -La 0.8 Sr 0.2 MnO 3-δ The air electrode layer (sintered at 800 °C for 3 hours) has an electrolyte layer thickness of about 15 μm, an air electrode layer length of about 8 cm, and a thickness of about 20 μm. Finally, Co(NO 3 ) 2 The solution was calcined at 600°C for 1 hour to prepare a catalyst, and auxiliary components were installed and sealed to obtain the high-stability proton conductor type CO 2 In situ hydrogenation electrochemical reactor.

[0065] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor, characterized in that: The high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor comprises: A porous structure fuel electrode support that supports the strength of the electrochemical reactor; Catalyst particles supported within the porous structure of the fuel electrode support; an electrolyte layer disposed on the upper part or the outer side of the fuel electrode support; and The air electrode layer is disposed on the upper part or outside of the electrolyte layer.

2. The high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor according to claim 1, characterized in that: The material of the fuel electrode support is a La-based electron conductor material with high stability to CO2; preferably, the material of the fuel electrode support includes La a (W 1-b Mo b ) 1-c M c O 12-δ (5.2≤a≤5.8, 0≤b≤0.4, 0≤c≤0.05, 0≤δ≤1, M includes Ni, Cu, Pd, Fe), La 1-x Sr x M 1-a M' a O 3-δ (0≤x≤0.3, 0≤a≤0.1, 0≤δ≤0.2, M includes Y, Yb, In, Sc, M' includes Ni, Cu, Pd, Fe), La 2-x M x Ce 2-a M' a O 7-δ (0≤x≤0.3, 0≤a≤0.2, 0≤δ≤0.35, M includes Mg, Ca, Ba, M' includes Ni, Cu, Pd, Fe), La 2-x M x Zr 2-a M' a O 7-δ (0≤x≤0.3, 0≤a≤0.2, 0≤δ≤0.35, M includes Mg, Ca, Ba, M' includes Ni, Cu, Pd, Fe) and La 1-x M x Nb 1-a M' a O4 (0≤x≤0.3, 0≤a≤0.1, M includes Mg, Ca, Sr, Ba, Yb, M' includes Ni, Cu, Pd, Fe) at least one; more preferably, the material of the fuel electrode support is La 5.4 (W 0.6 Mo 0.4 ) 0.95 Ni 0.05 O 12-δ ; The thickness of the fuel electrode support is 0.5-1 mm, and the porosity is 40-50%.

3. The high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor according to claim 1 or 2, characterized in that: The catalyst particles include Ni, Cu, Fe, Co, Gd 0.2 Ce 0.8 O 2-δ (GDC), Sm 0.2 Ce 0.8 O 2-δ (SDC), Er 0.4 Bi 1.6 At least one of O3(ESB); The content of the catalyst particles is 30-60wt% of the total mass of the fuel electrode support and the catalyst, and the particle size is 30-60nm.

4. The high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor according to any one of claims 1 to 3, characterized in that: The material of the electrolyte layer is a La-based electron conductor material with high stability to CO2; preferably, the material of the electrolyte layer includes La a M b WO 12-δ (5.2≤a≤5.8, 0≤b≤0.2, 0≤δ≤2, M includes Bi, K), La 1- x Sr x MO 3-δ (0≤x≤0.3, 0≤δ≤0.2, M includes Y, Yb, In, Sc), La 2-x M x Ce2O 7-δ (0≤x≤0.3, 0≤δ≤0.35, M includes Mg, Ca, Ba), La 2-x M x Zr2O 7-δ (0.1≤x≤0.3, 0≤δ≤0.35, M includes Mg, Ca, Ba) and La 1- x M x NbO4 (0≤x≤0.3, M includes at least one of Mg, Ca, Sr, Ba, Yb); more preferably, the material of the electrolyte layer is La 5.5 Bi 0.1 WO 11.4 ; The thickness of the electrolyte layer is 5-20 μm.

5. The high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor according to any one of claims 1 to 4, characterized in that: The material of the air electrode layer includes Bi 2-x Er x O3(ESB,0≤x≤0.5), La 1-x Sr x MnO 3-δ (LSM,0≤x≤0.5,0≤δ≤0.25), La 2-x Sr x NiO4(LSN,0≤x≤1), La 1-x Sr x Cr 0.5 Mn 0.5 O 3-δ (LSCM, 0≤x≤0.5, 0≤δ≤0.25) at least one; preferably Bi 1.6 Er 0.4 O3-La 0.8 Sr 0.2 MnO 3-δ ; The thickness of the air electrode layer is 10 to 40 μm, preferably 10 to 20 μm.

6. A method for preparing a high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor according to any one of claims 1 to 5, characterized in that: The preparation method comprises the following steps: (1) mixing the material powder of the fuel electrode support with a pore-forming agent and forming the mixture into a green body, and performing a first sintering to obtain a porous structure fuel electrode support; (2) attaching the material of the electrolyte layer to the surface of the porous structure fuel electrode support, and performing a second sintering to obtain an electrolyte layer-porous structure fuel electrode support structure; (3) attaching the air electrode material to the surface of the electrolyte layer and sintering for the third time to obtain an air electrode layer-electrolyte layer-porous fuel electrode support structure; (4) impregnating a catalyst solution into the porous fuel electrode support of the air electrode layer-electrolyte layer-porous structure fuel electrode support structure, and sintering for the fourth time to obtain an air electrode layer-electrolyte layer-catalyst / porous structure fuel electrode support structure; (5) Auxiliary components are installed on the air electrode layer-electrolyte layer-catalyst / porous fuel electrode support structure and it is sealed to obtain the high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor.

7. The preparation method according to claim 6, characterized in that: In step (1), the first sintering is carried out at a temperature of 1100 to 1300° C. for a time of 1 to 4 hours; In step (2), the second sintering is carried out at a temperature of 1300 to 1500° C. and for a time of 2 to 5 hours; In step (3), the temperature of the third sintering is 800-1000° C. and the time is 1-4 hours; In step (4), the temperature of the fourth sintering is 300-700° C., and the time is 1-3 hours.

8. Use of a high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor according to any one of claims 1 to 5 in the production of at least one of CO, CH4 or CH3OH by in-situ hydrogenation conversion of CO2.

9. The use according to claim 8, characterized in that: The method of application comprises the following steps: (1) introducing H2 into the fuel electrode of the high-stability proton conductor type CO2 in-situ hydrogenation electrochemical reactor to reduce the catalyst material and simultaneously dissolve metal nanoparticles in-situ from the fuel electrode support to alloy with the catalyst; (2) The gas introduced into the fuel electrode is switched to CO2, humid air is introduced into the air electrode side, and electricity is applied for reaction, so that CO2 can be in-situ hydrogenated to produce at least one of CO, CH4, and CH3OH.

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