Apparatus and method for synthesis of benzaldehyde based on all-vanadium redox flow battery

Abstract

This application provides an apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery. It utilizes a vanadium redox flow battery and two reaction chambers. Benzyl alcohol and a first catalyst are added to the first reaction chamber, and a second catalyst is added to the second reaction chamber. The process involves adding VO2-containing... + The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, and stirred in the first reaction chamber to allow VO2 to... + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ and benzaldehyde. Containing V 2+ The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber, so that V in the second reaction chamber... 2+ It is converted to V under the action of a second catalyst 3+ And hydrogen gas is released. The gas containing VO 2+ The positive electrolyte is returned to the positive electrode chamber, and the V-containing electrolyte is also returned to the positive electrode chamber. 3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the vanadium redox flow battery is charged by connecting a power source, which then removes the VO from the positive electrode electrolyte. 2+ Convert to VO2 + And the V in the negative electrode electrolyte 3+ Transformation V 2+ .

Description

Technical Field

[0001] This invention relates to the field of benzaldehyde preparation, and more specifically to an apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery. Background Technology

[0002] Benzaldehyde (BzH) is an important organic intermediate in the aromatic carbonyl compound family, widely used in the production of perfumes, dyes, pharmaceuticals (such as cancer treatment drugs), and agrochemicals. Currently, the liquid-phase oxidation of benzyl alcohol (BzOH) is one of the main methods for the industrial preparation of benzaldehyde, offering advantages such as energy saving, improved product selectivity, and prevention of catalyst deactivation. However, traditional oxidation methods suffer from numerous problems, limiting their further development and application.

[0003] Traditional methods typically use potassium permanganate or chromium-based compounds as oxidants. While these oxidants exhibit high oxidizing power during the reaction, they leave behind waste products such as metallic impurities. These residues not only pollute the environment but may also trigger secondary reactions, leading to the over-oxidation of benzaldehyde to benzoic acid, thereby reducing the selectivity and purity of the product. Furthermore, traditional methods usually require high temperatures, which increases energy consumption and introduces significant safety risks.

[0004] In recent years, with the promotion of green chemistry concepts, researchers have begun to explore more environmentally friendly and efficient methods for the synthesis of benzaldehyde. For example, a method based on polyoxometalate flow batteries (POM RFB) for the oxidation of benzyl alcohol and the production of hydrogen has been employed. However, this method still has the following problems:

[0005] 1. Low technological maturity: The technology of polyoxometalate flow batteries is not yet mature, and their reliability and stability in practical applications need further verification.

[0006] 2. High material costs: Polyoxometalate flow batteries require expensive precious metal catalysts, which increases production costs and limits their large-scale application.

[0007] 3. Poor stability: Polyoxometalate flow batteries have poor charge-discharge cycle stability, especially in reactions involving multiple electron transfers, where their performance is prone to degradation.

[0008] 4. Difficult product separation: The high viscosity of polyoxometalate solutions may lead to difficulties in separating the electrolyte from the organic products, increasing the complexity of subsequent processing.

[0009] 5. Harsh reaction conditions: The reaction needs to be carried out under heating conditions (≥60℃), which increases energy consumption and operational difficulty.

[0010] 6. Limited conversion rate: The conversion rate of benzyl alcohol is 98%, and there is still room for improvement.

[0011] In summary, existing methods for synthesizing benzaldehyde suffer from problems such as oxidant pollution, harsh reaction conditions, difficulties in product separation, and limited conversion rates. Therefore, developing an efficient, selective, and sustainable method for synthesizing benzaldehyde under mild conditions has become an important research direction. Summary of the Invention

[0012] The purpose of this invention is to overcome the aforementioned shortcomings of the prior art and provide an apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery. This addresses the technical problems of existing benzaldehyde synthesis methods, such as oxidant pollution, harsh reaction conditions, difficult product separation, and limited conversion rates. The apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery provided by this invention not only simplifies the production process but also conforms to the principles of green chemistry and has broad application prospects.

[0013] To achieve the aforementioned objectives, one aspect of the present invention provides an apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery, the apparatus comprising:

[0014] A vanadium redox flow battery comprises: an electrolyzer, a proton exchange membrane, a positive electrode chamber, a negative electrode chamber, a positive electrode, a negative electrode, a power source, and several wires; wherein:

[0015] The proton exchange membrane is placed inside the electrolyzer, which is divided into a positive electrode chamber and a negative electrode chamber.

[0016] The positive electrode is placed in the positive electrode chamber and is used to connect to the positive terminal of the power supply via a wire. The positive electrode chamber is used to contain VO2. + and / or VO 2+ The positive electrode electrolyte is such that the positive electrode is at least partially immersed in the positive electrode electrolyte;

[0017] The negative electrode is placed in the negative electrode chamber and is used to connect to the negative electrode of the power supply via a wire. The negative electrode chamber is used to contain V. 2+ and / or V 3+ The negative electrode electrolyte is such that the negative electrode is at least partially immersed in the negative electrode electrolyte;

[0018] The first reaction chamber contains benzyl alcohol and the first catalyst, receives the positive electrode electrolyte from the positive electrode chamber, and returns the reacted positive electrode electrolyte to the positive electrode chamber; and

[0019] The second reaction chamber is used to contain the second catalyst, receive the negative electrode electrolyte from the negative electrode chamber, and return the reacted negative electrode electrolyte to the negative electrode chamber.

[0020] The device is used for: in the first reaction chamber, VO2 +Benzyl alcohol is converted to VO under the action of the first catalyst. 2 + and benzaldehyde; in the second reaction chamber, V 2+ It is converted to V under the action of a second catalyst 3+ And release hydrogen gas; and release VO 2+ The positive electrolyte is returned to the positive electrode chamber, and the V-containing electrolyte is also returned to the positive electrode chamber. 3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the vanadium redox flow battery is charged by connecting a power source, which then removes the VO from the positive electrode electrolyte. 2+ Convert to VO2 + And the V in the negative electrode electrolyte 3+ Transformation V 2+ .

[0021] According to a second aspect of this application, a method for synthesizing benzaldehyde based on a vanadium redox flow battery is provided, comprising:

[0022] Provide the apparatus according to the first aspect of this application;

[0023] Benzyl alcohol and a first catalyst are added to the first reaction chamber, and a positive electrode electrolyte is added to the positive electrode chamber.

[0024] A second catalyst is added to the second reaction chamber, and a negative electrode electrolyte is added to the negative electrode chamber.

[0025] The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, and stirred in the first reaction chamber to allow VO2 to... + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ and benzaldehyde;

[0026] The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber, so that V in the second reaction chamber... 2+ It is converted to V under the action of a second catalyst 3+ Hydrogen gas is released.

[0027] According to a third aspect of this application, a method for synthesizing benzaldehyde based on a vanadium redox flow battery is provided, comprising:

[0028] The positive electrode chamber of the vanadium redox flow battery is connected to the first reaction chamber, and the negative electrode chamber of the vanadium redox flow battery is connected to the second reaction chamber.

[0029] Benzyl alcohol and a first catalyst are added to the first reaction chamber, and a positive electrode electrolyte containing VO2 is added to the positive electrode chamber. + ;

[0030] A second catalyst is added to the second reaction chamber, and a negative electrode electrolyte is added to the negative electrode chamber, wherein the negative electrode electrolyte contains V. 2+ ;

[0031] The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, and stirred in the first reaction chamber to allow VO2 to... + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ and benzaldehyde;

[0032] The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber, so that V in the second reaction chamber... 2+ It is converted to V under the action of a second catalyst 3+ And hydrogen gas is released; and

[0033] Will contain VO 2+ The positive electrolyte is returned to the positive electrode chamber, and the V-containing electrolyte is also returned to the positive electrode chamber. 3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the vanadium redox flow battery is charged by connecting a power source, which then removes the VO from the positive electrode electrolyte. 2+ Convert to VO2 + And the V in the negative electrode electrolyte 3+ Transformation V 2+ .

[0034] The apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery provided in the first to third aspects of this application have the following beneficial effects:

[0035] 1. The apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery of this application provide a simple, clean, and sustainable process for benzaldehyde preparation. It can be carried out under mild conditions without the need for high temperature and high pressure. Furthermore, the process is environmentally friendly and does not produce harmful substances. In addition, the process simplifies operational requirements and improves safety.

[0036] 2. In the apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery of this application, pentavalent vanadium ions are used as an oxidant in the chemical reaction. Stirring ensures thorough mixing of the liquid oxidant and liquid reactants, guaranteeing high reaction efficiency. Once utilized, vanadium ions can be regenerated in the redox flow battery and reused in the reaction, making the system sustainable.

[0037] 3. The apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery of this application exhibit high conversion rate, good selectivity, and fast reaction rate. This process achieves an impressive benzyl alcohol conversion rate of nearly 100%. It has a very high selectivity for benzaldehyde, reaching 99%. Furthermore, compared with conventional methods, the reaction rate is significantly faster, making this method highly efficient and beneficial for industrial applications.

[0038] 4. In the apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery of this application, the product and electrolyte are easily separated. Since the organic product benzaldehyde and the sulfuric acid solution are immiscible, the mixture will naturally separate into layers once stirring stops. This phase separation results in distinct layers, allowing for easy and efficient extraction of the desired organic product.

[0039] 5. The apparatus and method for synthesizing benzaldehyde based on an all-vanadium redox flow battery in this application avoid excessive oxidation. VO2 + With a suitable redox potential, benzyl alcohol can be oxidized to benzaldehyde, but not enough to further oxidize it to benzoic acid.

[0040] In summary, this invention enables the sustainable and clean production of high-purity benzaldehyde; effectively solves the problem of excessive oxidation in benzaldehyde production; and greatly simplifies the reaction conditions for benzaldehyde production. Attached Figure Description

[0041] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0042] Figure 1 This is a schematic diagram illustrating the working principle of an apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery according to an embodiment of the present invention.

[0043] Figure 2 An energy level diagram of the entire reaction system of an apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery according to an embodiment of the present invention;

[0044] Figure 3 This is a schematic diagram of the connection and experimental process of an apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery according to an embodiment of the present invention.

[0045] Figure 4A For benzyl alcohol, a reactant in CDCl3 1 H NMR spectrum;

[0046] Figure 4B benzaldehyde, a product of the reaction in CDCl3 1 H NMR spectrum;

[0047] Figure 5A Commercial benzaldehyde is shown. 1 H NMR spectrum;

[0048] Figure 5B Commercial benzaldehyde with VO2 was shown.+ The solution after being mixed for 24 hours in the presence of a catalyst 1 HNMR spectrum;

[0049] Figure 6A VO2 diluted 10-fold was shown + UV-Vis spectra of the electrolyte before and after reaction with benzyl alcohol;

[0050] Figure 6B VO2 diluted 10-fold was shown + UV-Vis spectra of the electrolyte before and after reaction with benzaldehyde;

[0051] Figure 7 This is a schematic diagram illustrating the degree of oxidation of benzyl alcohol under the influence of pentavalent vanadium ions;

[0052] Figure 8A The changes in benzyl alcohol / benzaldehyde concentrations over time are shown in five cyclic reactions.

[0053] Figure 8B The concentration of tetravalent vanadium / pentavalent vanadium changes over time during five cycles of reaction;

[0054] Figure 9 The figure shows the yield of the final benzaldehyde product in five cycles of reaction and the Faraday efficiency calculated accordingly.

[0055] Figure 10A A graph showing the amount of hydrogen produced over time during five reaction cycles;

[0056] Figure 10B UV-Vis spectra of vanadium electrolyte diluted 10-fold before and after the hydrogen evolution reaction (HER);

[0057] Figure 11A The LSV test data for benzyl alcohol and benzaldehyde are shown.

[0058] Figure 11B The LSV test data for V(IV) / V(V) are shown. Detailed Implementation

[0059] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0060] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0061] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0062] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0063] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0064] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass described in the embodiments of this application can be a mass unit known in the chemical industry, such as μg, mg, g, or kg.

[0065] The terms "first" and "second" are used for descriptive purposes only, to distinguish objects, such as substances, from one another, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. For example, without departing from the scope of the embodiments of this application, "first XX" may also be referred to as "second XX," and similarly, "second XX" may also be referred to as "first XX." Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0066] This invention describes a green and efficient method and apparatus for synthesizing benzaldehyde under mild conditions. The general concept is as follows: On the positive electrode side, a sulfuric acid solution containing pentavalent vanadium ions, generated from charging a vanadium redox flow battery, is mixed with pure benzyl alcohol and a catalyst. Under stirring, almost all of the benzyl alcohol is converted to benzaldehyde, and the yellow pentavalent vanadium ions are reduced to blue tetravalent vanadium ions. After stirring stops, the mixture rapidly separates into layers: the upper layer is benzaldehyde, and the lower layer is a pure blue tetravalent vanadium electrolyte. The upper layer is filtered to obtain high-purity benzaldehyde, and the lower layer is returned to the vanadium redox flow battery for reuse. Simultaneously, on the negative electrode side, the purple V-containing... 2+ The negative electrode electrolyte initiates hydrogen production on the HER catalyst in the reaction chamber, generating a green, V-containing gas. 3+ Negative electrode electrolyte. In summary, this method and apparatus achieve the decoupling synthesis and regeneration of benzaldehyde integrated with a vanadium redox flow battery. This not only simplifies benzaldehyde production but also aligns with green chemistry principles, minimizing waste and energy consumption. This versatile process is also applicable to the synthesis of other value-added chemicals.

[0067] The principle of this invention is explained as follows:

[0068] Figure 1 This is a schematic diagram illustrating the working principle of an apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery according to an embodiment of the present invention. Figure 1 As shown, the device comprises a full vanadium redox flow battery and a separate external reactor. The organic synthesis reaction occurs in the external reactor, which is connected to the positive electrode chamber. A sulfuric acid solution of VOSO4 is used as the positive electrode electrolyte in the flow battery and is charged to produce pentavalent vanadium VO2. + The charged positive electrode electrolyte is then circulated to an external reactor containing pure benzyl alcohol and a Co1 / NC (or Pt / C) catalyst. Simultaneously, the V generated during charging is... 2+ The negative electrode electrolyte is circulated to another external reaction chamber connected to the negative electrode chamber to produce hydrogen gas.

[0069] Figure 2 The diagram shows the energy diagram of the entire reaction system of an apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery according to an embodiment of the present invention, wherein VO2... + Using V as a medium, in an external reaction chamber connected to the positive electrode chamber, the positive electrode electrolyte selectively synthesizes benzaldehyde through redox-mediated oxidation of benzyl alcohol, while in another external reaction chamber connected to the negative electrode chamber, V... 2+ Using it as a medium, hydrogen gas is produced.

[0070] As shown in the figure, in this system for synthesizing benzaldehyde based on a vanadium redox flow battery, VO2 is generated in the external reactor connected to the positive electrode chamber. +Acting as a charge carrier, it initiates the oxidation of benzyl alcohol at the organic-catalyst-electrolyte three-phase boundary. Meanwhile, on the negative electrode side, V generated in the all-vanadium redox flow cell... 2+ The electrolyte can participate in the hydrogen evolution reaction as it passes through the catalyst bed, or it can be naturally oxidized by atmospheric oxygen. VO is generated separately in the two reaction chambers. 2+ and V 3+ All of these will be recycled back into the vanadium redox flow battery, and under the charging action of an external power source, VO 2+ and V 3+ Separate regeneration, that is, re-conversion into VO2. + and V 2+ This is to provide for subsequent reaction cycles.

[0071] The chemical reaction equations involved in the above process are as follows:

[0072] Electrochemical charging chemical formula: VO 2+ +H2O+V 3+ →VO2 + V 2+ +2H +

[0073] Chemical formula for benzyl alcohol oxidation reaction:

[0074] Chemical formula for hydrogen evolution reaction:

[0075] Net reaction chemical formula: C7H8O→C7H6O+H2

[0076] According to a first aspect of this application, an apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery is provided, the apparatus comprising:

[0077] A vanadium redox flow battery comprises: an electrolyzer, a proton exchange membrane, a positive electrode chamber, a negative electrode chamber, a positive electrode, a negative electrode, a power source, and several wires; wherein:

[0078] The proton exchange membrane is placed inside the electrolyzer, which is divided into a positive electrode chamber and a negative electrode chamber.

[0079] The positive electrode is placed in the positive electrode chamber and is used to connect to the positive terminal of the power supply via a wire. The positive electrode chamber is used to contain VO2. + and / or VO 2+ The positive electrode electrolyte is such that the positive electrode is at least partially immersed in the positive electrode electrolyte;

[0080] The negative electrode is placed in the negative electrode chamber and is used to connect to the negative electrode of the power supply via a wire. The negative electrode chamber is used to contain V. 2+ and / or V 3+ The negative electrode electrolyte is such that the negative electrode is at least partially immersed in the negative electrode electrolyte;

[0081] The first reaction chamber contains benzyl alcohol and the first catalyst, receives the positive electrode electrolyte from the positive electrode chamber, and returns the reacted positive electrode electrolyte to the positive electrode chamber; and

[0082] The second reaction chamber is used to contain the second catalyst, receive the negative electrode electrolyte from the negative electrode chamber, and return the reacted negative electrode electrolyte to the negative electrode chamber.

[0083] The device is used for: in the first reaction chamber, VO2 + Benzyl alcohol is converted to VO under the action of the first catalyst. 2 + and benzaldehyde; in the second reaction chamber, V 2+ It is converted to V under the action of a second catalyst 3+ And release hydrogen gas; and release VO 2+ The positive electrolyte is returned to the positive electrode chamber, and the V-containing electrolyte is also returned to the positive electrode chamber. 3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the vanadium redox flow battery is charged by connecting a power source, which then removes the VO from the positive electrode electrolyte. 2+ Convert to VO2 + And the V in the negative electrode electrolyte 3+ Transformation V 2+ .

[0084] In this embodiment, "the positive electrode is at least partially immersed in the positive electrolyte" means that the positive electrode can be partially immersed in the positive electrolyte or completely submerged in it. "The negative electrode is at least partially immersed in the negative electrolyte" means that the negative electrolyte can be partially immersed in the negative electrolyte or completely submerged in the positive electrolyte.

[0085] According to an embodiment of this application, the proton exchange membrane is a naphthol membrane, preferably Nafion 117.

[0086] According to embodiments of this application, both the negative and positive electrodes are made of carbon felt.

[0087] According to embodiments of this application, the first catalyst is a catalyst for the oxidation of benzyl alcohol. The first catalyst can be a catalyst in which single-atom cobalt (Co1 / NC) is supported on a nitrogen-doped carbon substrate, or it can be a catalyst in which platinum (Pt / C) is supported on activated carbon. In a specific embodiment, the first catalyst is a Co1 / NC catalyst.

[0088] According to embodiments of this application, the second catalyst is a hydrogen production catalyst, which may be a catalyst in which molybdenum sulfide nanosheets (MoS2 / CF) are supported on a carbon felt.

[0089] According to embodiments of this application, the positive electrode electrolyte is a positive electrode electrolyte used in vanadium redox flow batteries. In one specific embodiment, the positive electrode electrolyte contains VO2.+ and / or VO 2+ Sulfuric acid solution.

[0090] According to embodiments of this application, the negative electrode electrolyte is a negative electrode electrolyte used in vanadium redox flow batteries. In one specific embodiment, the negative electrode electrolyte contains V... 2+ and / or V 3+ sulfuric acid solution.

[0091] According to an embodiment of this application, the first reaction chamber is connected to the positive electrode chamber via several liquid guide pipes to form a circulation loop that allows the positive electrode electrolyte to circulate between the first reaction chamber and the positive electrode chamber. A first pump is provided in the circulation loop. Under the action of the first pump, the charged electrolyte containing VO2... + The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber for the oxidation reaction of benzyl alcohol. After the reaction is completed, the VO2-containing product generated by the reaction is pumped out. 2+ The positive electrode electrolyte returns from the first reaction chamber to the positive electrode chamber.

[0092] According to an embodiment of this application, the second reaction chamber is connected to the negative electrode chamber via several liquid guide pipes to form a circulation loop that allows the negative electrode electrolyte to circulate between the second reaction chamber and the negative electrode chamber. A second pump is provided in the circulation loop. Under the action of the second pump, the charged electrolyte containing V... 2+ The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber for the oxidation reaction of benzyl alcohol. After the reaction is completed, the product containing V is pumped out by the action of a second pump. 3+ The negative electrode electrolyte returns from the second reaction chamber to the negative electrode chamber.

[0093] In this embodiment of the application, the first pump and the second pump can be unidirectional pumps, such as centrifugal pumps.

[0094] According to an embodiment of this application, a first reaction chamber is connected to a positive electrode chamber via a liquid guide pipe, and a bidirectional pump is installed on the liquid guide pipe to allow the positive electrode electrolyte to transfer back and forth between the first reaction chamber and the positive electrode chamber. A second reaction chamber is connected to a negative electrode chamber via a liquid guide pipe, and a bidirectional pump is installed on the liquid guide pipe to allow the positive electrode electrolyte to transfer back and forth between the second reaction chamber and the negative electrode chamber. The bidirectional pump can be a bidirectional peristaltic pump or a bidirectional diaphragm pump.

[0095] According to embodiments of this application, the second reaction chamber can be connected to a hydrogen collection device for collecting hydrogen. In one specific embodiment, the hydrogen collection device is a hydrogen storage tank. In another specific embodiment, the hydrogen collection device may also be equipped with a gas flow meter to monitor the hydrogen generation rate and total amount.

[0096] According to an embodiment of this application, the first reactor is further equipped with a magnetic stirrer to agitate the reaction liquid in the first reaction chamber, thereby promoting the reaction of VO2. + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ And benzaldehyde.

[0097] According to an embodiment of this application, the first reaction chamber may be further connected to an organic phase extraction device. Thus, after the reaction in the first reaction chamber is completed, and the mixture is allowed to stand to allow the organic phase containing the organic product and the liquid phase containing the vanadium electrolyte to separate into layers, the organic phase can be separated using the organic phase extraction device.

[0098] According to a second aspect of this application, a method for synthesizing benzaldehyde based on a vanadium redox flow battery is provided. The method includes:

[0099] Provide the apparatus according to the first aspect of this application;

[0100] Benzyl alcohol and the first catalyst are added to the first reaction chamber, and a positive electrode electrolyte is added to the positive electrode chamber.

[0101] A second catalyst is added to the second reaction chamber, and a negative electrode electrolyte is added to the negative electrode chamber.

[0102] The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, and stirred in the first reaction chamber to allow VO2 to... + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ and benzaldehyde;

[0103] The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber, so that V in the second reaction chamber... 2+ It is converted to V under the action of a second catalyst 3+ Hydrogen gas is released.

[0104] It is understandable that the V in the negative electrode electrolyte in the negative electrode chamber 2+ In addition to being converted into V through hydrogen evolution reaction with a catalyst in the second reaction chamber. 3+ It can also be naturally oxidized by atmospheric oxygen in the second reaction chamber or the negative electrode chamber, thus converting into V. 3+ .

[0105] In the embodiments of this application, the reactions occurring in the first and second reaction chambers are both carried out at room temperature (25°C). Since the reaction can be carried out at room temperature without the need for high temperature and high pressure, this method is simple, easy to operate, energy-saving, and reduces costs.

[0106] According to an embodiment of this application, the first reactor is further equipped with a magnetic stirrer. After the positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, the magnetic stirrer stirs the positive electrode electrolyte in the first reaction chamber, thereby promoting VO2... + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ And benzaldehyde. In one specific embodiment, the magnetic stirrer continuously stirs for several hours, optionally for at least 5 hours, at a stirring speed of 600 rpm to ensure that benzyl alcohol is oxidized to benzaldehyde as completely as possible.

[0107] In the first reaction chamber, undisturbed, the vanadium-containing positive electrode electrolyte and benzyl alcohol naturally separate into layers due to their immiscibility, with benzyl alcohol on top and the vanadium electrolyte on the bottom. The inventors discovered that, depending on the concentration of the vanadium-containing positive electrode electrolyte, the catalyst particles can be retained in the upper organic phase or precipitated in the lower vanadium-containing electrolyte phase. For example, in one specific embodiment, when the concentration of the vanadium-containing positive electrode electrolyte is less than or equal to 1M, the catalyst material is organic-phase-loving; that is, with this concentration of vanadium-containing positive electrode electrolyte, the catalyst is retained in the upper organic phase.

[0108] According to an embodiment of this application, the method further includes: stopping stirring in a first reaction chamber and allowing the reaction liquid in the first reaction chamber to separate into layers; extracting the upper phase, centrifuging, and filtering to separate the first catalyst, which is in solid form, from the organic product, which is in liquid form.

[0109] In this embodiment, after stirring in the first reaction chamber is stopped and the mixture is allowed to stand, it naturally separates into two phases. The upper layer contains the first catalyst and organic products, and the lower layer is an electrolyte containing vanadium ions. Understandably, at this time, the vanadium ions in the electrolyte include VO42O3 obtained through the reaction. 2+ Optionally, it also includes unreacted VO2. + The upper phase is extracted from the first reaction chamber and then centrifuged and filtered to separate the solid first catalyst from the liquid organic product. The first catalyst, crucial to the reaction, is separated in this process for reuse in subsequent reactions, thereby improving process efficiency and sustainability.

[0110] According to embodiments of this application, the separated organic product is further washed with sulfuric acid solution to remove residual vanadium ions, thereby obtaining a high-purity benzaldehyde product.

[0111] According to an embodiment of this application, the method further includes: stopping stirring in a first reaction chamber and allowing the mixture to stand until the reaction liquid in the first reaction chamber separates into layers; and then reacting the generated VO-containing solution with the solution. 2+ The positive electrolyte is returned to the positive electrode chamber, where the generated electrolyte containing V...3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the power is turned on to charge the vanadium redox flow battery, thereby converting the VOCs into electrolyte. 2+ Converted into VO2 + and V 3+ Convert to V 2+ .

[0112] In this embodiment, after the redox reaction in the first and second reaction chambers stops, the generated product containing VO is... 2+ The positive electrode electrolyte returns from the first reaction chamber to the positive electrode chamber, where the generated electrolyte containing V... 3+ The negative electrode electrolyte returns from the second reaction chamber to the negative electrode chamber, and then the power is turned on to charge the vanadium redox flow battery, thereby removing the VO from the positive electrode electrolyte. 2+ Converted into VO2 + And the V in the negative electrode electrolyte 3+ Convert to V 2+ Thus, the VO-containing compounds generated by the two redox-mediated reactions... 2+ Positive electrode electrolyte and V-containing 3+ The negative electrode electrolyte is reintroduced into the flow battery system for recharging, thereby allowing the VOC in the positive electrode electrolyte to be released under the influence of an external electric field. 2+ Converted into VO2 + And the V in the negative electrode electrolyte 3+ Convert to V 2 + The recharged electrolyte is then ready for the next round of benzaldehyde synthesis and hydrogen evolution reaction, ensuring a continuous and efficient workflow.

[0113] According to embodiments of this application, before carrying out the reaction to prepare benzaldehyde, the preparation of the positive electrode electrolyte and the negative electrode electrolyte includes the following steps: [The text abruptly shifts to a seemingly unrelated topic about reacting VO2+ with a specific chemical substance]. 2+ Electrolytes were added to the positive and negative electrode chambers respectively, and the power was turned on for charging, thereby obtaining a solution containing VO2 in the positive electrode chamber. + The positive electrode electrolyte is used to obtain a solution containing V in the negative electrode chamber. 2+ The negative electrode electrolyte.

[0114] According to embodiments of this application, the VO-containing 2+ The concentration of the electrolyte is 1M.

[0115] According to embodiments of this application, before the first catalyst is added to the first reaction chamber, a certain amount of VO2-containing... + The positive electrode electrolyte is washed to avoid potential side reactions of the catalyst in subsequent reactions.

[0116] According to a third aspect of this application, a method for synthesizing benzaldehyde based on a vanadium redox flow battery is provided, comprising:

[0117] The positive electrode chamber of the vanadium redox flow battery is connected to the first reaction chamber, and the negative electrode chamber of the vanadium redox flow battery is connected to the second reaction chamber.

[0118] Benzyl alcohol and a first catalyst are added to the first reaction chamber, and a positive electrode electrolyte containing VO2 is added to the positive electrode chamber. + ;

[0119] A second catalyst is added to the second reaction chamber, and a negative electrode electrolyte is added to the negative electrode chamber, wherein the negative electrode electrolyte contains V. 2+ ;

[0120] The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, and stirred in the first reaction chamber to allow VO2 to... + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ and benzaldehyde;

[0121] The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber, so that V in the second reaction chamber... 2+ It is converted to V under the action of a second catalyst 3+ And hydrogen gas is released; and

[0122] Will contain VO 2+ The positive electrolyte is returned to the positive electrode chamber, and the V-containing electrolyte is also returned to the positive electrode chamber. 3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the vanadium redox flow battery is charged by connecting a power source, which then removes the VO from the positive electrode electrolyte. 2+ Convert to VO2 + And the V in the negative electrode electrolyte 3+ Transformation V 2+ .

[0123] According to an embodiment of this application, the positive electrode electrolyte contains VO2. + and / or VO 2+ The sulfuric acid solution; the negative electrode electrolyte is a solution containing V 2+ and / or V 3+ sulfuric acid solution.

[0124] According to an embodiment of this application, the method further includes stopping stirring in a first reaction chamber and allowing it to stand until the reaction liquid in the first reaction chamber separates into layers; extracting the upper phase, centrifuging, and filtering, thereby separating the first catalyst, which is in the solid phase, from the organic product, which is in the liquid phase.

[0125] In this embodiment, after stirring in the first reaction chamber is stopped and the mixture is allowed to stand, it naturally separates into two phases. The upper layer contains the first catalyst and organic products, and the lower layer is an electrolyte containing vanadium ions. Understandably, at this time, the vanadium ions in the electrolyte include VO42O3 obtained through the reaction. 2+ Optionally, it also includes unreacted VO2. + The upper phase is extracted from the first reaction chamber and then centrifuged and filtered to separate the solid first catalyst from the liquid organic product. The first catalyst, crucial to the reaction, is separated in this process for reuse in subsequent reactions, thereby improving process efficiency and sustainability.

[0126] According to embodiments of this application, the separated organic product is further washed with sulfuric acid solution to remove residual vanadium ions, thereby obtaining a high-purity benzaldehyde product.

[0127] According to embodiments of this application, before carrying out the reaction to prepare benzaldehyde, the preparation of the positive and negative electrode electrolytes includes the following steps: [The text abruptly shifts to a seemingly unrelated topic about reacting VO2+ with a specific substance]. 2+ Electrolytes were added to the positive and negative electrode chambers respectively, and the vanadium redox flow battery was charged by connecting a power source, thereby obtaining a solution containing VO2 in the positive electrode chamber. + The positive electrode electrolyte, while simultaneously obtaining V in the negative electrode chamber. 2+ The negative electrode electrolyte.

[0128] According to embodiments of this application, the VO-containing 2+ The concentration of the electrolyte is 1M.

[0129] According to embodiments of this application, before the first catalyst is added to the first reaction chamber, a certain amount of VO2-containing... + The positive electrode electrolyte is washed to avoid potential side reactions of the catalyst in subsequent reactions.

[0130] The embodiments of this application are further explained below through several experimental examples.

[0131] Example 1: Construction of an apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery

[0132] A vanadium redox flow battery is constructed, comprising: an electrolyzer, a proton exchange membrane, a positive electrode chamber, a negative electrode chamber, a positive electrode, a negative electrode, a power source, and several wires. The proton exchange membrane is placed within the electrolyzer, dividing the electrolyzer into the positive electrode chamber and the negative electrode chamber. The positive electrode is placed within the positive electrode chamber and is connected to the positive terminal of the power source via wires. The negative electrode is placed within the negative electrode chamber and is connected to the negative terminal of the power source via wires.

[0133] The reactor provides a first reaction chamber and a second reaction chamber. The first reaction chamber is connected to the positive electrode chamber via several liquid delivery pipes, and a drive pump is installed on these pipes. The second reaction chamber is connected to the negative electrode chamber via several liquid delivery pipes, and a drive pump is also installed on these pipes. A magnetic stirrer is installed on the first reaction chamber, and the second reactor is also connected to a hydrogen storage tank.

[0134] The connection of each component can be referred to the diagram. Figure 3 .

[0135] Example 2: Preparation of Electrolyte

[0136] The preparation methods for the positive and negative electrode electrolytes are as follows:

[0137] A 1M VOSO4 / 1M H2SO4 solution was prepared by dissolving VOSO4 in H2SO4. 40 mL of this solution was placed in the positive electrode chamber of a vanadium redox flow battery, and 20 mL in the negative electrode chamber. The battery was charged, thus obtaining 40 mL of a 1M VOSO4 / 1M H2SO4 solution in the positive electrode chamber. + The positive electrode electrolyte was used to obtain 20 mL of 1 M V solution in the negative electrode chamber. 2+ The negative electrode electrolyte.

[0138] Take 20 mL of 1M VO2-containing solution from the positive electrode chamber. + The positive electrode electrolyte is used to wash the first catalyst Co1 / NC to eliminate potential side reactions of Co1 / NC in subsequent reactions. Thus, 20 mL of positive and negative electrode electrolytes are contained in the negative and positive electrode chambers respectively for subsequent steps.

[0139] Example 3: Benzaldehyde synthesis and hydrogen evolution reaction

[0140] The experimental procedure can be roughly referred to. Figure 3 .

[0141] At room temperature, 20 mg of washed Co1 / NC catalyst and 1 mL of pure benzyl alcohol were added to the first reaction chamber. MoS2 / CF catalyst was added to the second reaction chamber.

[0142] Take 20 mL of 1M VO2 from Example 2 + The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, and 1M VO2 is added. + After the solution and benzyl alcohol are mixed, they separate into layers, with the catalyst spontaneously entering the upper benzyl alcohol layer. A magnetic stirrer is used in the first reaction chamber to stir at 600 rpm for approximately 5 hours, until the reaction solution changes from yellow to blue. At this point, benzyl alcohol is oxidized to benzaldehyde, and the VO2 in the positive electrode electrolyte... + Restored to VO 2+Stop stirring and let stand for 10 minutes to allow the reaction mixture to naturally separate into two phases: the upper layer contains the catalyst and organic products, and the lower layer is a vanadium-containing electrolyte.

[0143] The upper phase was extracted from the first reaction chamber and separated by centrifugation and filtration. The filter residue was collected as a solid Co1 / NC catalyst for reuse in subsequent reactions. The filtrate, containing benzaldehyde, was then mixed with a certain amount of 0-4M sulfuric acid solution and subjected to acid washing with stirring for 5 minutes to dissolve any residual vanadium ions in the benzaldehyde. After stirring was stopped, the mixture was allowed to stand for 10 minutes. The benzaldehyde, now free of vanadium ions, separated from the sulfuric acid solution and was collected as the final high-concentration benzaldehyde product.

[0144] Meanwhile, the 20 mL of 1M containing V in Example 2 2+ The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber, where a rapid and spontaneous hydrogen evolution reaction occurs, and the V in the negative electrode electrolyte is transferred to the second reaction chamber. 2+ Transform into V 3+ The generated hydrogen gas is collected.

[0145] Subsequently, two redox-mediated reactions produced VO-containing... 2+ Positive electrode electrolyte and V-containing 3+ The negative electrode electrolyte is reintroduced into the vanadium redox flow battery system for recharging. The recharged positive and negative electrode electrolytes are then ready for the next round of benzaldehyde synthesis and hydrogen evolution reaction.

[0146] Example 4: Spectroscopic analysis of reactants and products in the oxidation reaction of benzyl alcohol

[0147] use 1 1H NMR spectroscopy was used to analyze the reactants and products. The spectra were tested and recorded using deuterated chloroform (CDCl3) as the solvent. Figure 4A The spectrum of pure benzyl alcohol is shown; this substance was used as a reactant in the synthesis of benzaldehyde. Figure 4B The reaction products were shown 1 The 1H NMR spectrum showed a signal consistent with that of benzaldehyde, indicating that the purity of the obtained benzaldehyde was as high as 99%. Importantly, the spectrum did not show a signal of benzoic acid, proving that excessive oxidation of benzyl alcohol to benzoic acid was avoided in the reaction.

[0148] To further confirm VO2 + The oxidation of p-benzyl alcohol stops at the benzaldehyde stage and does not further oxidize to benzoic acid. Pure commercial benzaldehyde is reacted with VO2... + The electrolyte and the same catalyst were mixed and stirred for 24 hours. Figure 5A Commercial benzaldehyde is shown. 1 H NMR spectrum. Figure 5B Commercial benzaldehyde with VO2 was shown.+ The solution after being mixed for 24 hours in the presence of a catalyst 1 HNMR spectrum. From Figures 5A-5B It can be seen that the benzaldehyde before and after stirring... 1 The 1H NMR spectrum showed no change, proving that benzaldehyde would not be further oxidized under the reaction conditions.

[0149] After reacting with benzyl alcohol, the color of the positive electrode electrolyte changes from yellow to blue, as shown in the UV-Vis absorption spectrum. Figure 6A VO2 diluted 10-fold was shown + UV-Vis spectra of the electrolyte before and after reaction with benzyl alcohol. Figure 6B VO2 diluted 10-fold was shown + UV-Vis spectra of the electrolyte before and after reaction with benzaldehyde. Figure 6A In the figure, the absorption peak at 765 nm corresponds to V(IV), proving that VO2 + After accepting electrons, benzyl alcohol is reduced to VO. 2+ In comparison, Figure 6B In China, VO2 + After being mixed with benzaldehyde and catalyst for 12 hours, its UV-Vis spectrum remained unchanged, indicating that VO2 + It cannot be reduced by benzaldehyde. Therefore, through VO2... + The production of benzaldehyde by oxidizing benzyl alcohol avoids the formation of the byproduct benzoic acid.

[0150] Overall, in vanadium redox flow batteries, VO2 + Oxidation of benzyl alcohol can produce almost pure benzaldehyde. This method features simple reaction conditions, a high reaction rate, easy product separation, and effective prevention of over-oxidation. A schematic diagram of the degree of benzyl alcohol oxidation under the action of pentavalent vanadium ions is shown in the embodiments of this application. Figure 7 As shown.

[0151] The apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery according to embodiments of the present invention are expected to significantly promote the sustainable and clean production of benzaldehyde and can be applied to the synthesis of other organic chemicals.

[0152] Example 5 Product Yield Test

[0153] Following the experimental procedure in Example 4, five electrochemical charge-chemical discharge cycles were performed.

[0154] The changes in the concentrations of benzyl alcohol / benzaldehyde over time during the five-cycle reaction are as follows: Figure 8A As shown, the concentration of tetravalent vanadium / pentavalent vanadium changes over time as follows: Figure 8B As shown.

[0155] Figure 9The figure shows the yield of the final benzaldehyde product in five cycles and the calculated Faraday efficiency. The yield of benzaldehyde depends primarily on the separation of the oil phase benzaldehyde and the aqueous electrolyte.

[0156] In the experiment, after the reaction stirring stopped and the mixture stood for 10 minutes, the two phases could separate into two distinct layers. The upper layer of benzaldehyde could be directly collected and the solid catalyst could be separated by centrifugation. To remove residual vanadium ions from the benzaldehyde, it was mixed with a certain amount of 0-4M sulfuric acid solution and acid-washed with stirring for 5 minutes. The residual vanadium ions in the benzaldehyde would dissolve in the sulfuric acid solution. After stirring stopped and the mixture stood for 10 minutes, the benzaldehyde with vanadium ions removed could separate into two distinct layers with the sulfuric acid solution and be collected as the final high-concentration benzaldehyde product.

[0157] from Figure 9 As can be seen, the yield of the first reaction is lower than that of subsequent reactions because benzaldehyde itself has a certain solubility in vanadium electrolyte, making it difficult to collect this dissolved benzaldehyde. After the first reaction, the dissolution of benzaldehyde reaches saturation, thus improving the yield of benzaldehyde in subsequent reactions. The yield not reaching 100% is mainly due to slight losses during collection, acid washing, and transfer.

[0158] Example 6: Hydrogen evolution reaction data

[0159] The amount of hydrogen reacted was monitored and analyzed over time during five reaction cycles. Figure 10A This is a graph showing the amount of hydrogen produced over time during five reaction cycles. Figure 10B The UV-Vis spectra of the vanadium electrolyte before and after the HER reaction demonstrate that divalent vanadium V(II) is completely converted to trivalent vanadium V(III) in the HER reaction.

[0160] Example 7 LSV Test

[0161] To investigate pentavalent vanadium (VO2) + The reason why benzyl alcohol is precisely oxidized to benzaldehyde without further oxidation to benzoic acid is that benzyl alcohol, benzaldehyde, and pentavalent vanadium (VO2) + The sample was subjected to LSV (Linear Sweep Voltammetry) testing. The test conditions were: 1 mV / s scan rate and 1 M H2SO4 solution.

[0162] Depend on Figure 11A It can be seen that the onset potential for the oxidation of benzyl alcohol is 0.87V (vs. RHE), and the onset potential for the oxidation of benzaldehyde is 1.11V (vs. RHE). Figure 11BUnder the same test conditions, the potential of V(IV) / V(V) is 1.09V (vs. RHE), significantly higher than 0.87V and slightly lower than 1.11V. Therefore, pentavalent vanadium (VO₂) + It can oxidize benzyl alcohol but does not have enough overpotential to oxidize benzaldehyde.

[0163] The apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery provided in the first to third aspects of this application have the following beneficial effects:

[0164] 1. The apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery of this application provide a simple, clean, and sustainable process for benzaldehyde preparation. It can be carried out under mild conditions without the need for high temperature and high pressure. Furthermore, the process is environmentally friendly and does not produce harmful substances. In addition, the process simplifies operational requirements and improves safety.

[0165] 2. In the apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery of this application, pentavalent vanadium ions are used as an oxidant in the chemical reaction. Stirring ensures thorough mixing of the liquid oxidant and liquid reactants, guaranteeing high reaction efficiency. Once utilized, vanadium ions can be regenerated in the redox flow battery and reused in the reaction, making the system sustainable.

[0166] 3. The apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery of this application exhibit high conversion rate, good selectivity, and fast reaction rate. This process achieves an impressive benzyl alcohol conversion rate of nearly 100%. It has a very high selectivity for benzaldehyde, reaching 99%. Furthermore, compared with conventional methods, the reaction rate is significantly faster, making this method highly efficient and beneficial for industrial applications.

[0167] 4. In the apparatus and method for synthesizing benzaldehyde based on a vanadium redox flow battery of this application, the product and electrolyte are easily separated. Since the organic product and the aqueous acid solution are immiscible, the mixture naturally separates into layers once stirring stops. This phase separation results in distinct layers, allowing for easy and efficient extraction of the desired organic product.

[0168] 5. The apparatus and method for synthesizing benzaldehyde based on an all-vanadium redox flow battery in this application avoid excessive oxidation. VO2 + With a suitable redox potential, benzyl alcohol can be oxidized to benzaldehyde, but not enough to further oxidize it to benzoic acid.

[0169] In summary, this invention enables the sustainable and clean production of high-purity benzaldehyde; effectively solves the problem of excessive oxidation in benzaldehyde production; and greatly simplifies the reaction conditions for benzaldehyde production.

[0170] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An apparatus for synthesizing benzaldehyde based on a vanadium redox flow battery, the apparatus comprising: A vanadium redox flow battery comprises: an electrolyzer, a proton exchange membrane, a positive electrode chamber, a negative electrode chamber, a positive electrode, a negative electrode, a power source, and several wires; wherein: The proton exchange membrane is placed inside the electrolytic cell, which divides the electrolytic cell into the positive electrode chamber and the negative electrode chamber; The positive electrode is placed in the positive electrode chamber and is used to connect to the positive electrode of the power supply via a wire. The positive electrode chamber is used to contain VO2. + and / or VO 2+ The positive electrode is at least partially immersed in the positive electrode electrolyte. The negative electrode is placed in the negative electrode chamber and is used to connect to the negative electrode of the power supply via a wire. The negative electrode chamber is used to contain V. 2+ and / or V 3+ The negative electrode is at least partially immersed in the negative electrode electrolyte. A first reaction chamber is used to contain benzyl alcohol and a first catalyst, and to receive the positive electrode electrolyte from the positive electrode chamber, and to return the reacted positive electrode electrolyte to the positive electrode chamber; and The second reaction chamber is used to contain the second catalyst, receive the negative electrode electrolyte from the negative electrode chamber, and return the reacted negative electrode electrolyte to the negative electrode chamber. The device is used for: in the first reaction chamber, the VO2 + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ and benzaldehyde; in the second reaction chamber, the V 2+ It is converted into V under the action of the second catalyst. 3+ And hydrogen gas is released; and the VO containing the gas is released. 2+ The positive electrolyte is returned to the positive electrode chamber, and the V-containing electrolyte is... 3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the vanadium redox flow battery is charged by connecting the power supply, thus removing the VO from the positive electrode electrolyte. 2+ Convert to VO2 + and the V in the negative electrode electrolyte 3+ Transformation V 2+ .

2. The apparatus of claim 1, wherein, The proton exchange membrane is Nafion 117; and / or Both the negative electrode and the positive electrode are made of carbon felt; and / or The first catalyst is a catalyst in which single-atom cobalt (Co1 / NC) is supported on a nitrogen-doped carbon substrate; and / or The second catalyst is a catalyst in which molybdenum sulfide nanosheets (MoS2 / CF) are supported on a carbon felt; and / or The positive electrode electrolyte contains VO2. + and / or VO 2+ sulfuric acid solution; and / or The negative electrode electrolyte contains V 2+ and / or V 3+ Sulfuric acid solution.

3. The apparatus of claim 1, wherein, The first reaction chamber is connected to the positive electrode chamber via several liquid guide pipes to form a circulation loop that allows the positive electrode electrolyte to circulate between the first reaction chamber and the positive electrode chamber. A first pump is installed in this circulation loop. The second reaction chamber is connected to the negative electrode chamber through several liquid guide pipes to form a circulation loop that allows the negative electrode electrolyte to circulate in the second reaction chamber and the negative electrode chamber, wherein a second pump is provided in the circulation loop.

4. The apparatus of claim 1, wherein, The second reaction chamber is also connected to a hydrogen collection device for collecting the generated hydrogen.

5. A method for synthesizing benzaldehyde based on a vanadium redox flow battery, comprising: Provide an apparatus according to any one of claims 1-4; Benzyl alcohol and the first catalyst are added to the first reaction chamber, and the positive electrode electrolyte is added to the positive electrode chamber; The second catalyst is added to the second reaction chamber, and the negative electrode electrolyte is added to the negative electrode chamber; The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, and stirred in the first reaction chamber to ensure that the VO2... + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ and benzaldehyde; The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber, so that the V in the second reaction chamber... 2+ It is converted into V under the action of the second catalyst. 3+ Hydrogen gas is released.

6. The method of claim 5, wherein, Further includes: Stop stirring in the first reaction chamber and let it stand until the reaction liquid in the first reaction chamber separates into layers; The upper phase is extracted, centrifuged, and filtered to separate the first catalyst, which is in solid form, from the organic product, which is in liquid form.

7. The method of claim 6, wherein, The separated organic products were further washed with sulfuric acid solution to remove residual vanadium ions.

8. The method of claim 5, further comprising: Stop stirring in the first reaction chamber and let it stand until the reaction liquid in the first reaction chamber separates into layers; The generated containing the VO 2+ The positive electrode electrolyte is returned to the positive electrode chamber, and the generated electrolyte containing V... 3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the power supply is turned on to charge the vanadium redox flow battery, thereby charging the VO 2+ Converted into the VO2 + and the V 3+ Transformed into the V 2+ .

9. The method of claim 5, wherein, Before carrying out the reaction to prepare benzaldehyde, the preparation of the positive electrode electrolyte and the negative electrode electrolyte includes the following steps: Will contain VO 2+ The electrolyte is added to the positive electrode chamber and the negative electrode chamber respectively, and the power supply is turned on to charge the vanadium redox flow battery, thereby obtaining a solution containing VO2 in the positive electrode chamber. + The positive electrode electrolyte, while simultaneously obtaining the V in the negative electrode chamber. 2+ The negative electrode electrolyte.

10. A method for synthesizing benzaldehyde based on a vanadium redox flow battery, comprising: The positive electrode chamber of the vanadium redox flow battery is connected to the first reaction chamber, and the negative electrode chamber of the vanadium redox flow battery is connected to the second reaction chamber. Benzyl alcohol and a first catalyst are added to the first reaction chamber, and a positive electrode electrolyte containing VO2 is added to the positive electrode chamber. + ; A second catalyst is added to the second reaction chamber, and a negative electrode electrolyte is added to the negative electrode chamber, wherein the negative electrode electrolyte contains V. 2+ ; The positive electrode electrolyte is transferred from the positive electrode chamber to the first reaction chamber, and stirred in the first reaction chamber to allow VO2 to form. + Benzyl alcohol is converted to VO under the action of the first catalyst. 2+ and benzaldehyde; The negative electrode electrolyte is transferred from the negative electrode chamber to the second reaction chamber, such that V in the second reaction chamber... 2+ It is converted into V under the action of the second catalyst. 3+ And hydrogen gas is released; and Will contain VO 2+ The positive electrolyte is returned to the positive electrode chamber, and the V-containing electrolyte is also returned to the positive electrode chamber. 3+ The negative electrode electrolyte is returned to the negative electrode chamber, and the vanadium redox flow battery is charged by connecting a power source, thus removing the VO from the positive electrode electrolyte. 2+ Convert to VO2 + and the V in the negative electrode electrolyte 3+ Transformation V 2+ .

Images