Electrochemical reactor and method for synergetic resource utilization of sodium chloride and carbon dioxide

Abstract

The invention discloses an electrochemical reactor and method for synergistic resource utilization of sodium chloride and carbon dioxide, and belongs to the technical field of electrochemistry. The reactor comprises an anode chamber, a middle chamber and a cathode chamber; through holes are formed in the two sides of the middle chamber, the through holes of the anode chamber and the cathode chamber correspond to the through holes of the middle chamber respectively, the three-chamber electrolytic cell is electrified at the normal temperature, the middle chamber serves as an electrolyte circulation area, a sodium chloride aqueous solution is introduced for ion conduction, the anode chamber is provided with a nitrogen inlet channel, and the cathode chamber is provided with a nitrogen outlet channel. The cathode chamber is provided with a carbon dioxide inlet channel, carbon dioxide is introduced, so that generated sodium bicarbonate or sodium carbonate is separated out in a solid crystal form on a hydrophobic layer of the negative electrode, and hydrogen escapes at the same time. An electrolysis system with a specific structure is constructed, an efficient electrode material is adopted, carbon dioxide conversion and sodium chloride electrolysis reaction are achieved under the conditions of normal temperature and normal pressure, and chlorine, hydrogen and sodium carbonate or sodium bicarbonate are co-produced.

Description

Technical Field

[0001] The present application relates to the field of electrochemical technology, and in particular to an electrochemical reactor and method for the coordinated resource utilization of sodium chloride and carbon dioxide. Background Art

[0002] With the continued growth of global industrial activity, carbon dioxide (CO2) emissions continue to climb, exacerbating the greenhouse effect. While existing carbon capture and storage (CCS) technologies can temporarily alleviate carbon emissions, their high cost and lack of resource recovery hinder widespread commercial application. On the other hand, chlorine and hydrogen, as basic chemical raw materials, are widely used in polyvinyl chloride, bleach, disinfectants, and synthetic ammonia. Traditional chlorine production relies primarily on energy-intensive brine electrolysis, while hydrogen is obtained through natural gas reforming or water electrolysis, resulting in high energy consumption and significant pollution. Furthermore, sodium carbonate (Na2CO3), a key raw material in industries like glass and detergents, is primarily produced through the Solvay process, which relies on resources like limestone and ammonia. This process produces numerous byproducts and places a heavy environmental burden. Traditional alkali production suffers from significant resource efficiency issues, resulting in low raw material utilization and considerable waste.

[0003] Taking the ammonia-soda process and the Hou-soda process as examples, these processes not only require high-purity salt water at near-saturation concentration as raw material, but also rely on synthetic ammonia as an auxiliary reactant. Synthetic ammonia production itself is energy-intensive and costly, generating significant carbon emissions and placing a heavy burden on the environment.

[0004] Therefore, developing a new electrochemical method that can realize the coupled utilization of CO2 and NaCl under green and low-carbon conditions and co-produce three high-value-added chemicals is of great practical significance for achieving closed-loop resource utilization. Summary of the Invention

[0005] To address the deficiencies in the prior art, the present invention provides a resource utilization method based on electrochemical coupled conversion. By constructing an electrolysis system with a specific structure and using high-efficiency electrode materials, carbon dioxide conversion and sodium chloride electrolysis reactions are simultaneously achieved under normal temperature and pressure conditions to co-produce chlorine, hydrogen, and sodium carbonate or sodium bicarbonate.

[0006] The present invention adopts the following technical solutions.

[0007] The first aspect of the present invention discloses an electrochemical reactor for the coordinated resource utilization of sodium chloride and carbon dioxide, comprising an anode chamber, an intermediate chamber, and a cathode chamber connected in sequence; Through holes are provided on both sides of the middle chamber. The through hole of the anode chamber corresponds to the through hole on one side of the middle chamber, and the hydrophobic layer of the positive electrode is connected to the through hole of the anode chamber; the through hole of the cathode chamber corresponds to the other side of the middle chamber, and the hydrophobic layer of the negative electrode is connected to the through hole of the cathode chamber; the area of ​​the through holes is smaller than the area of ​​the positive electrode and the negative electrode; The three-chamber electrolytic cell is placed at room temperature and energized. The middle chamber serves as the electrolyte circulation area, and a sodium chloride aqueous solution is introduced for ion conduction. The anode chamber is provided with a nitrogen inlet channel, and nitrogen is introduced for immediate separation and recovery of generated chlorine. The cathode chamber is provided with a carbon dioxide inlet channel, and carbon dioxide is introduced to cause the generated sodium bicarbonate or sodium carbonate to precipitate in the hydrophobic layer of the negative electrode in the form of solid crystals, while hydrogen escapes.

[0008] Preferably, the purge flow rate of nitrogen in the anode chamber is 5-50 mL / min, ensuring that the chlorine partial pressure is lower than the explosion limit during the reaction.

[0009] Preferably, the CO2 inlet rate of the cathode chamber is 3-30 mL / min, and is evenly distributed through any one of the porous titanium plate or hydrophobic carbon paper on the back side of the cathode; and the sodium chloride aqueous solution is 0.5-3 M NaCl solution.

[0010] Preferably, the method for preparing the electrode comprises the following steps: Matrix preparation: Select the matrix material, ultrasonically clean the matrix with deionized water and anhydrous ethanol in sequence, and then dry it in an oven for later use; Catalytic layer coating: The catalyst is coated on the surface of the substrate and formed into a catalytic layer after drying; Hydrophobic layer treatment: PTFE emulsion is applied to one side of the catalyst layer, and then heat-treated to form a hydrophobic layer; Preparation of cation exchange layer: Nafion ® The solution is coated on the other side of the catalytic layer and a selective ion channel is formed after curing and annealing.

[0011] Preferably, the matrix material serving as a conductive skeleton is any matrix material with a stable water reduction potential.

[0012] Preferably, the catalyst loading is 1.0-2.0 mg / cm².

[0013] Preferably, the loading of the PTFE emulsion is 0.8-1.2 mg / cm², and the contact angle of the hydrophobic layer is ≥150°.

[0014] Preferably, in the preparation of the cation exchange layer, commercial Nafion membrane can be used to replace Nafion ® Solution coating was performed to closely fit the commercial Nafion membrane on the other side of the catalyst layer.

[0015] A second aspect of the present invention discloses an electrochemical method for the coordinated resource utilization of sodium chloride and carbon dioxide, based on the electrochemical reactor for the coordinated resource utilization of sodium chloride and carbon dioxide, comprising the following steps: Place the assembled three-chamber electrolyzer at room temperature; Inject NaCl solution into the middle chamber, pre-flow nitrogen into the anode chamber and pre-flow carbon dioxide into the cathode chamber to exclude air; Connect a DC power supply, set the current density, introduce nitrogen into the anode chamber, introduce carbon dioxide into the cathode chamber, and collect the product.

[0016] Preferably, the set current density is 100-500 mA / cm².

[0017] Compared with the prior art, the beneficial effects of the present invention include at least: This process innovatively adopts a composite electrode structure design, and this technological breakthrough has multiple significant advantages. First, in terms of catalytic performance, the specially designed catalytic layer can provide excellent electrocatalytic activity, significantly improving the reaction efficiency. More importantly, by introducing the innovative design of the hydrophobic layer, not only the rapid desorption and separation of the reaction products is achieved, but also an effective physical barrier is constructed to ensure the strict independence between the reaction chambers. Systematic performance tests have shown that this hydrophobically modified electrode structure can increase the product separation efficiency by more than 30%, and the service life of the electrode is extended by 2-3 times compared to the traditional design, which provides a solid technical guarantee for the long-term stable operation of the entire reaction system. This design successfully overcomes the two major technical difficulties that have long existed in traditional electrochemical reactors: low product separation efficiency and cross-liquid problems between reaction chambers.

[0018] Compared with the traditional alkali production process, this process shows obvious technical advantages. The ammonia-soda method and combined alkali production method currently widely used in industry not only require the concentration of the raw salt water to be close to saturation, but also need to use a variety of raw materials such as synthetic ammonia and carbon dioxide. The process flow is complicated and the raw material cost is high. This process only requires the combination of raw salt water and carbon dioxide, and the requirement for brine concentration is significantly reduced. It is particularly noteworthy that even under relatively low concentration conditions, the process can still efficiently promote the formation of solid crystals of sodium bicarbonate or sodium carbonate. This feature simplifies the process flow and reduces energy consumption. This groundbreaking process design has opened up a new path for the development of electrochemical alkali production technology and has important industrial application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a model diagram of the electrochemical reactor in the present invention; Figure 2 Schematic diagram of the electrochemical method of the present invention; In the figure: 1. Anode chamber; 2. Middle chamber; 3. Cathode chamber. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. The embodiments described in this application are only part of the embodiments of the present invention, not all of them. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] Example 1 of the present invention provides an electrochemical reactor for the coordinated resource utilization of sodium chloride and carbon dioxide, such as Figure 1-2 As shown, the reactor is a customized three-chamber electrolyzer, comprising an anode chamber 1, an intermediate chamber 2, and a cathode chamber 3 connected in sequence; Through holes are provided on both sides of the intermediate chamber 2. The through hole of the anode chamber 1 corresponds to the through hole on one side of the intermediate chamber 2, and the anode is located between the two through holes. The through hole of the cathode chamber 3 corresponds to the other side of the intermediate chamber 2, and the cathode is located between the two through holes. The area of ​​the through holes is smaller than the area of ​​the anode and the cathode.

[0022] The three-chamber electrolytic cell is placed in a room temperature environment. The middle chamber 2 serves as the electrolyte circulation area, and a sodium chloride aqueous solution is introduced for ion conduction. The anode chamber 1 is provided with a nitrogen inlet channel, and nitrogen is introduced for immediate separation and recovery of generated chlorine. The cathode chamber 3 is provided with a carbon dioxide inlet channel, and carbon dioxide is introduced to cause the generated sodium bicarbonate or sodium carbonate to spontaneously precipitate in the form of solid crystals on the back water surface of the cathode, while hydrogen escapes from the back side of the cathode.

[0023] In a preferred but non-limiting embodiment of the present invention, the three-chamber electrolytic cell is preferably made of polytetrafluoroethylene.

[0024] The volume ratio of the anode chamber 1 , the intermediate chamber 2 , and the cathode chamber 3 is optimized to be 1:0.1:1 (eg, 50 mL:5 mL:50 mL).

[0025] The nitrogen purge flow rate in the anode chamber was 5-50 mL / min (precisely controlled by a mass flow meter) to ensure that the chlorine partial pressure was below the explosion limit (<5%).

[0026] The CO2 inlet rate of the cathode chamber is 3-30 mL / min, evenly distributed through either the back-side porous titanium plate or the hydrophobic carbon paper, and the gas-liquid contact area is increased by 40%. Preferably, the CO2 concentration is >20%.

[0027] The sodium chloride aqueous solution is 0.5-3 M NaCl solution (prepared with deionized water).

[0028] Temperature and pressure: The reaction is maintained at 25±1℃ throughout the process, and the operation is carried out at normal pressure to avoid the need for high-pressure equipment.

[0029] The three-chamber electrochemical reactor described in the present invention achieves efficient and coordinated resource utilization of sodium chloride and carbon dioxide through zoning control. The reactor adopts a unique chamber separation design. The anode chamber 1 achieves instant separation and recovery of chlorine through nitrogen purge technology. The middle chamber 2 serves as the electrolyte circulation area and is introduced with refined salt water solution. The cathode chamber 3 innovatively sets a carbon dioxide inlet channel on the back side of the cathode.

[0030] During the reaction, chlorine gas generated at the anode is efficiently separated from the anode chamber under nitrogen and continuously discharged from the system. Precisely controlled reaction conditions in the cathode region allow the generated sodium bicarbonate or sodium carbonate to spontaneously precipitate as solid crystals on the cathode's backwater surface, automatically separating the product from the reaction solution. This three-chamber design not only effectively prevents product cross-contamination but also simplifies subsequent product purification processes through physical separation, significantly improving reaction efficiency and product yield.

[0031] It is particularly worth mentioning that the carbon dioxide-passing design on the back side of the cathode chamber optimizes the gas-liquid mass transfer efficiency, while the anode nitrogen purge system ensures the efficient recovery and safe operation of chlorine. The entire system realizes the co-production of three high-value-added products: chlorine, hydrogen and sodium bicarbonate or sodium carbonate, and has significant industrial application value.

[0032] Example 2 of the present invention provides a method for preparing an electrode in an electrochemical reactor for the coordinated resource utilization of sodium chloride and carbon dioxide, comprising the following steps: Step 1, substrate preparation: select a substrate material, ultrasonically clean the substrate with deionized water and anhydrous ethanol in sequence to remove surface impurities, and then dry it in an oven for later use; The base material serves as a conductive skeleton and is any one of base materials with stable water reduction potential, such as hydrophobic carbon paper, titanium felt, titanium mesh or stainless steel; the cleaning time is 15 minutes each, and the oven temperature is 60°C.

[0033] Step 2, catalytic layer coating: coating the catalyst on the substrate surface and forming a catalytic layer after drying; In a preferred but non-limiting embodiment of the present invention, step 2 specifically comprises: Step 2.1, mixing the catalyst and the solvent, and forming a uniform slurry after ultrasonic dispersion; Further preferably, the catalyst is any one of an IrO2 catalyst, a Pt / C catalyst or other catalysts that catalyze anode and cathode reaction; The solvent is any one of organic solvents such as methanol, ethanol or isopropanol, and can even be pure water. The mass ratio of the catalyst to the solvent is set according to different solvents.

[0034] Step 2.2: Spray the slurry evenly onto the substrate surface, controlling the catalyst loading to 1.0-2.0 mg / cm². In step 2.3, after coating, the electrode was placed in an oven at 80 °C for preliminary drying for 10 min, and the spraying was repeated three times to ensure uniform coverage.

[0035] The catalytic layer is the middle layer of the working surface, responsible for water reduction to produce H2 and OH - .

[0036] Step 3, hydrophobic layer (PTFE layer) treatment: PTFE emulsion is applied to one side of the electrode, and then heat-treated to form a hydrophobic layer; In a preferred but non-limiting embodiment of the present invention, step 3 specifically comprises: Step 3.1: dilute the PTFE emulsion (60 wt%) to 10 wt% and add a small amount of surfactant (such as TritonX-100) to improve dispersion. Step 3.2: Spray the PTFE emulsion onto the back side of the electrode (Nafion ® On the other side of the layer), the loading was controlled to be 0.8-1.2 mg / cm²; In step 3.3, after coating, the electrode was placed in a muffle furnace for heat treatment at 250°C for 1 hour to form a nanoscale hydrophobic structure with a contact angle of ≥150°.

[0037] Directed H2 discharge: The hydrophobic layer (PTFE layer) forms a gas diffusion channel. When H2 bubbles escape from the back side, they carry the NaHCO3 microcrystals (particle size 1-5 μm) generated by the reaction, achieving product self-stripping and reducing scaling on the electrode surface.

[0038] Step 4, cation exchange layer (Nafion ® Preparation of Nafion ® The solution is applied to the other side of the electrode and then solidified and annealed to form a selective ion channel. Alternatively, a commercial Nafion membrane can be directly applied to the electrode to achieve a similar effect. In a preferred but non-limiting embodiment of the present invention, step 4 specifically comprises: Step 4.1, Nafion ® The solution (Dupont™ D520) was diluted to 5 wt% and sonicated for 20 min to eliminate bubbles; Step 4.2: Use a spray gun to evenly spray Nafion on the surface of the catalyst layer. ®Solution, after each spraying, solidify and dry at 80℃ for 10 minutes, spray 3 times in total, and the final dry film thickness is controlled at 5-8 μm; Step 4.3: anneal the electrode at 120 °C for 1 hour to enhance the Nafion ® Mechanical strength of the film (peel force ≥ 1.5N / cm).

[0039] OH - Local confinement: cation exchange layer (Nafion ® layer) allows Na + Passes but blocks OH - Diffusion causes the local pH on the cathode surface to rise to 12-13, promoting CO2 to CO3² - Conversion (reaction formula: CO2 + 2OH - → CO3² - + H2O), while avoiding OH - The supersaturation of sodium carbonate or sodium bicarbonate caused by diffusion into the bulk phase is too low.

[0040] Step 5, performance verification: testing the performance by scanning electron microscope and electrochemical workstation; In a preferred but non-limiting embodiment of the present invention, step 5 specifically comprises: Step 5.1, observe the morphology of each layer using a scanning electron microscope (SEM) to confirm that there are no cracks or delamination; In step 5.2, use an electrochemical workstation to test the hydrogen evolution performance of the cathode in a 1 M NaCl solution to ensure that the potential meets the design requirements (e.g., ≤ -0.8 V vs. SHE) at a current density of 200 mA / cm².

[0041] It is worth noting that the inventors realized that the Nafion loading capacity affects the product separation efficiency. Therefore, they designed an experiment to fix other conditions (such as current density 200 mA / cm², CO2 flow rate 15 mL / min) and only change the Nafion loading capacity (0.5 / 1.0 / 1.5 mg / cm²). They evaluated the efficiency of H2 carrying NaHCO3 microcrystals and calculated the solid mass after evaporation of the cathode liquid. See the table below:

[0042] It can be seen that the comprehensive performance is best when the Nafion loading is 1.0 mg / cm².

[0043] This patent proposes innovative technical solutions for electrode materials and structural design. The main electrode utilizes a specially treated titanium felt as the substrate material. A composite electrode structure is formed by uniformly coating the titanium felt with an IrO2 catalytic layer. The optimized IrO2 loading is controlled within the range of 0.5-2 mg / cm², a parameter range that has been experimentally verified to balance catalytic activity and economic efficiency. In particular, a hydrophobic functional layer is innovatively constructed using PTFE nanoparticle spraying technology on the back of the electrode. The hydrophobicity is significantly enhanced through a heat treatment process at 200-250°C. This temperature range has been shown to effectively enhance the hydrophobic effect of the PTFE nanoparticles without damaging the electrode substrate.

[0044] This composite electrode structure has multiple technical advantages: the IrO2 coating on the front provides excellent electrocatalytic activity, ensuring the efficient progress of the chlorine evolution reaction and the sodium bicarbonate formation reaction; the nano-PTFE hydrophobic layer on the back not only promotes the rapid desorption and separation of products (such as chlorine bubbles), but also forms an effective physical barrier to prevent the penetration and diffusion of the salt water solution in the middle chamber into the cathode chamber and the anode chamber, thus maintaining the chamber independence of the three-chamber reactor. Experimental data show that this hydrophobically modified electrode structure can improve the product separation efficiency by more than 30%, while extending the electrode service life by 2-3 times, providing a reliable guarantee for the long-term stable operation of the system. This electrode design cleverly combines catalytic activity and interface regulation to solve technical bottlenecks such as product separation difficulties and chamber cross-flow in traditional electrochemical reactors.

[0045] Example 3 of the present invention provides an electrochemical method for the coordinated resource utilization of sodium chloride and carbon dioxide, comprising the following steps: Step 1, placing the assembled electrolytic cell in a constant temperature water bath; The temperature of the constant temperature water bath is 25±1°C; Step 2: inject NaCl solution into the middle chamber, pre-flow N2 into the anode chamber and pre-flow CO2 into the cathode chamber for 5 minutes to exclude air; Step 3: Connect a DC power supply, set the current density, and set the time to collect the product.

[0046] The DC power supply is a CHI 760E electrochemical workstation with a current density of 100-500 mA / cm².

[0047] In a preferred but non-limiting embodiment of the present invention, the obtained product is analyzed and characterized: Cl2 quantification: Anode exhaust was absorbed by 10% KI solution and titrated using the iodine titration method (GB / T 15437-2019). The Faradaic efficiency was calculated to be 95±1.5% (n=3).

[0048] H2 detection: Cathode gas was analyzed by gas chromatography (GC-2014, TCD detector, nitrogen carrier gas), and the H2 purity was >99.5%.

[0049] Characterization of NaHCO3: The cathode precipitated solid was washed with deionized water and dried at 60°C. XRD (Bruker D8Advance) confirmed that the crystalline form was pure NaHCO3. It is worth noting that this method can produce sodium carbonate or sodium bicarbonate, which is determined by the amount of CO2 introduced (and the amount of OH generated). - If there is an excess of CO2, sodium bicarbonate is produced; if there is a small amount of CO2, sodium carbonate is produced. Purity determination: After dissolution, the acid-base titration method (GB / T 210.2-2004) was used, and the purity was 98.7 ± 0.3%.

[0050] Energy consumption calculation: average cell voltage 4.8 V, energy consumption per ton of Cl2 1450 kWh (conventional process 2500 kWh).

[0051] Further preferably, a long-term stability test is performed on the electrochemical reactor: The reactor was operated continuously for 120 h, and samples were taken every 24 h for analysis of key data: Cl2 Faradaic efficiency: 95% initially → 92% after 120 h.

[0052] Contact angle of the cathode PTFE layer: 152° initially → 138° after 120 h (still superhydrophobic).

[0053] NaHCO3 purity fluctuation: 97.5-98.9%.

[0054] In summary, the electrochemical reactor described in this invention operates at room temperature and pressure, eliminating the need for high-voltage equipment. It co-produces three high-value-added chemicals, improving resource utilization by over 30%. Specifically, the Faradaic efficiency of Cl₂ is ≥95%, the purity of H₂ is >99.5%, and the purity of NaHCO₃ is ≥98.7%. It has significant industrialization potential, with an electrode life of >120 hours and a 42% reduction in energy consumption. Furthermore, compared to existing ammonia-soda processes and Hou's alkali processes, this invention requires only a lower concentration of sodium chloride aqueous solution for efficient operation, completely avoiding the use of synthetic ammonia and significantly reducing raw material costs and energy consumption. Furthermore, this invention innovatively achieves the recycling of by-products and co-produces a variety of high-value-added products, including chlorine, hydrogen, and sodium carbonate or bicarbonate. Chlorine and hydrogen, as basic chemical raw materials, are widely used in the production of products such as hydrochloric acid, polyvinyl chloride (PVC), pesticides, and bleaching agents. They also have important applications in water treatment, electronics, and metallurgy. Of particular note is the ability of this method to efficiently crystallize sodium bicarbonate even with relatively low sodium chloride solution concentrations. This feature not only simplifies the process, reduces equipment investment and operating costs, but also significantly reduces energy consumption. Compared to traditional processes that require strict saturated brine, this process offers greater adaptability to raw materials and lowers operating costs.

[0055] Compared with the prior art, the beneficial effects of the present invention include at least: This process innovatively adopts a composite electrode structure design, and this technological breakthrough has multiple significant advantages. First, in terms of catalytic performance, the specially designed catalytic layer can provide excellent electrocatalytic activity, significantly improving the reaction efficiency. More importantly, by introducing the innovative design of the hydrophobic layer, not only the rapid desorption and separation of the reaction products is achieved, but also an effective physical barrier is constructed to ensure the strict independence between the reaction chambers. Systematic performance tests have shown that this hydrophobically modified electrode structure can increase the product separation efficiency by more than 30%, and the service life of the electrode is extended by 2-3 times compared to the traditional design, which provides a solid technical guarantee for the long-term stable operation of the entire reaction system. This design successfully overcomes the two major technical difficulties that have long existed in traditional electrochemical reactors: low product separation efficiency and cross-liquid problems between reaction chambers.

[0056] Compared with the traditional alkali production process, this process shows obvious technical advantages. The ammonia-soda method and combined alkali production method currently widely used in industry not only require the concentration of the raw salt water to be close to saturation, but also need to use a variety of raw materials such as synthetic ammonia and carbon dioxide. The process flow is complicated and the raw material cost is high. This process only requires the combination of raw salt water and carbon dioxide, and the requirement for brine concentration is significantly reduced. It is particularly noteworthy that even under relatively low concentration conditions, the process can still efficiently promote the formation of solid crystals of sodium bicarbonate. This feature simplifies the process flow and reduces energy consumption. This groundbreaking process design has opened up new avenues for the development of electrochemical alkali production technology and has important industrial application value.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. An electrochemical reactor for the coordinated resource utilization of sodium chloride and carbon dioxide, characterized in that: It comprises an anode chamber (1), an intermediate chamber (2) and a cathode chamber (3) connected in sequence; Through holes are provided on both sides of the intermediate chamber (2); the through hole of the anode chamber (1) corresponds to the through hole on one side of the intermediate chamber (2); the hydrophobic layer of the positive electrode is connected to the through hole of the anode chamber (1); the through hole of the cathode chamber (3) corresponds to the other side of the intermediate chamber (2); the hydrophobic layer of the negative electrode is connected to the through hole of the cathode chamber (3); the area of ​​the through holes is smaller than the area of ​​the positive electrode and the negative electrode; The three-chamber electrolytic cell is placed at room temperature and energized. The middle chamber (2) serves as an electrolyte circulation zone, into which a sodium chloride aqueous solution is introduced for ion conduction. The anode chamber (1) is provided with a nitrogen inlet channel, into which nitrogen is introduced for immediate separation and recovery of generated chlorine. The cathode chamber (3) is provided with a carbon dioxide inlet channel, into which carbon dioxide is introduced so that the generated sodium bicarbonate or sodium carbonate is precipitated in the hydrophobic layer of the negative electrode in the form of solid crystals, while hydrogen escapes.

2. The electrochemical reactor for collaborative resource utilization of sodium chloride and carbon dioxide according to claim 1, wherein: The nitrogen purge flow rate in the anode chamber is 5-50 mL / min, ensuring that the chlorine partial pressure is lower than the explosion limit during the reaction.

3. The electrochemical reactor for collaborative resource utilization of sodium chloride and carbon dioxide according to claim 1, wherein: The CO2 inlet rate of the cathode chamber is 3-30 mL / min, and is evenly distributed through any one of the porous titanium plate or hydrophobic carbon paper on the back side of the cathode; the sodium chloride aqueous solution is 0.5-3 M NaCl solution.

4. The electrochemical reactor for collaborative resource utilization of sodium chloride and carbon dioxide according to claim 1, wherein: The preparation method of the electrode comprises the following steps: Matrix preparation: Select the matrix material, ultrasonically clean the matrix with deionized water and anhydrous ethanol in sequence, and then dry it in an oven for later use; Catalytic layer coating: The catalyst is coated on the surface of the substrate and formed into a catalytic layer after drying; Hydrophobic layer treatment: PTFE emulsion is applied to one side of the catalyst layer, and then heat-treated to form a hydrophobic layer; Preparation of cation exchange layer: Nafion ® The solution is coated on the other side of the catalytic layer and a selective ion channel is formed after curing and annealing.

5. The electrochemical reactor for collaborative resource utilization of sodium chloride and carbon dioxide according to claim 4, characterized in that: The matrix material serves as a conductive skeleton and is any matrix material with a stable water reduction potential.

6. The electrochemical reactor for collaborative resource utilization of sodium chloride and carbon dioxide according to claim 4, characterized in that: The catalyst loading is 1.0-2.0 mg / cm².

7. The electrochemical reactor for collaborative resource utilization of sodium chloride and carbon dioxide according to claim 4, characterized in that: The PTFE emulsion has a loading of 0.8-1.2 mg / cm² and a hydrophobic layer contact angle of ≥150°.

8. The electrochemical reactor for collaborative resource utilization of sodium chloride and carbon dioxide according to claim 4, characterized in that: In the preparation of the cation exchange layer, commercial Nafion membrane can be used to replace Nafion ® Solution coating was performed to closely fit the commercial Nafion membrane on the other side of the catalyst layer.

9. An electrochemical method for the coordinated resource utilization of sodium chloride and carbon dioxide, based on the electrochemical reactor for the coordinated resource utilization of sodium chloride and carbon dioxide according to any one of claims 1 to 8, characterized in that: The following steps are involved: Place the assembled three-chamber electrolyzer at room temperature; Injecting NaCl solution into the middle chamber (2), pre-flowing nitrogen into the anode chamber (1), and pre-flowing carbon dioxide into the cathode chamber (3) to exclude air; Connect a DC power supply, set the current density, introduce nitrogen into the anode chamber (1), introduce carbon dioxide into the cathode chamber (3), and collect the product.

10. The electrochemical method for the coordinated resource utilization of sodium chloride and carbon dioxide according to claim 9, characterized in that: The set current density is 100-500 mA / cm².

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