A method and system for an off-board electrocatalytic reaction

Abstract

The application discloses a kind of off-site electrocatalytic reaction method and reaction system.The off-site electrocatalytic reaction method includes: electrolyte ion pair in battery system carries out electron exchange reaction with electrode, obtains oxidation potential or reduction potential;Obtain the electrolyte of oxidation potential or reduction potential enters the independent reaction system outside battery system, and carries out oxidation-reduction reaction with reactant in reaction system to obtain mixture containing reaction product;After separation, after oxidation-reduction reaction, electrolyte returns to the battery system again to obtain oxidation potential or reduction potential.The novel off-site electrocatalytic tandem reaction technology provided by the application can move the complex reaction involving gas, liquid, solid and other phases out of the electrode surface, and place the reaction process outside the battery, avoiding the contamination of reactants and / or products on the electrode, catalyst, separator, etc.;The reaction system built by the off-site electrocatalytic synthesis technology runs stably, can be used for basic theory research, and has practical application significance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electrocatalysis, and particularly relates to a kind of off-site electrocatalytic reaction method and reaction system. BACKGROUND

[0002] Wind, light, water, tidal heat and other renewable resources can be used to produce green electricity. Using green electricity, organic conversion, alkane / alkene / arene activation, carbon dioxide reduction, hydrogen sulfide decomposition, water decomposition to produce hydrogen and oxygen, etc. can be used by electrocatalytic technology. Electro-catalytic technology mainly includes anode tank, cathode tank, diaphragm, etc., in which the anode tank undergoes oxidation reaction, the cathode tank undergoes reduction reaction, and the diaphragm separates the anode and cathode electrolyte and allows protons or hydroxyl ions to penetrate, realizing the electrical conductivity of the whole system.

[0003] Current electrocatalytic synthesis is to put the reactants into the anode or cathode electrolyte, which undergoes chemical reaction process on the surface of the electrode or its supported catalyst, to generate target products. For organic reactants, especially cyclic organic compounds and aromatic hydrocarbons, it is usually easy to undergo polymerization, deposition and other side reaction processes on the electrode surface, causing the effective area of the electrode to decrease and the mass transfer to be limited. In addition, the swelling and dissolution of organic matter to the diaphragm have harmful effects, causing the failure or activity decrease of the whole electrocatalytic reaction system, which cannot be stably and continuously operated, resulting in fatal inefficiency and short life in industrial scale-up application. In addition, the current electrocatalytic synthesis is a half-reaction, i.e. only organic reaction occurs on the anode or cathode side, and gas is produced on the other side of the electrode. Because of the pressure imbalance on both sides of the diaphragm, material penetration between the two sides of the diaphragm will occur in the actual production process, the service life of the diaphragm is short, and the system operation is also unstable, and the electric resources are also wasted.

[0004] Therefore, in order to realize large-scale industrial continuous, stable and efficient application of electrocatalytic process, it is urgent to innovate the current electrocatalytic reaction method, i.e. to avoid the pollution, swelling, covering of the electrode and diaphragm by the reactants and / or products, and to change the traditional reaction method. It is urgent to develop a new electrocatalytic organic synthesis reaction technology to realize stable and continuous operation of the reaction system and industrial application scale-up. SUMMARY

[0005] Therefore, the present application provides an off-site electrocatalytic reaction method and reaction system, which mainly aims to solve the technical problem that the reactants and / or products of electrocatalytic organic reaction easily pollute, swell and cover the electrode and diaphragm.

[0006] In one aspect, the present application provides an off-site electrocatalytic reaction method, which comprises the following steps:

[0007] The off-site electrocatalytic reaction method comprises the following steps:

[0008] The electrolyte ions in the battery system exchange electrons with the electrode to obtain oxidation potential or reduction potential; the electrolyte obtaining oxidation potential or reduction potential enters an independent reaction system outside the battery system, and exchanges redox reaction with reactants in the reaction system to obtain a mixture containing reaction products, and after separation, the electrolyte after the redox reaction returns to the battery system to obtain oxidation potential or reduction potential again.

[0009] The battery system and the reaction system in the application are independent systems, and the two systems can be connected by a pipeline for the flow of electrolyte between the battery system and the reaction system.

[0010] The electrolyte in the application is the electrolyte that exchanges electrons with the electrode to obtain oxidation potential or reduction potential after the battery system is powered on.

[0011] The above off-site electrocatalytic reaction method of the application is to move the chemical reaction of the reactants in the electrolytic cell to another reaction site outside the electrolytic cell, and only the circulation and delivery of the electrolyte between the electrolytic cell and the reaction site are needed, so that the problems of pollution, swelling and covering of the electrode or the separator caused by the chemical reaction of the reactants in the electrolytic cell in the traditional technology can be avoided.

[0012] The above off-site electrocatalytic method of the application can be applied to the following five reaction modes:

[0013] The first mode: the anode electrolytic cell is connected with the oxidation reaction system to perform oxidation reaction alone.

[0014] The second mode: the cathode electrolytic cell is connected with the reduction reaction system to perform reduction reaction alone.

[0015] The third mode: the anode electrolytic cell is connected with the oxidation reaction system to perform oxidation reaction alone, and at the same time, the cathode electrolytic cell is connected with the reduction reaction system to perform reduction reaction alone; the oxidation reaction system and the reduction reaction system perform chemical reaction independently; that is, in parallel mode.

[0016] The fourth mode: the anode electrolytic cell is connected with the oxidation reaction system to perform oxidation reaction, and the cathode electrolytic cell is connected with the reduction reaction system to perform reduction reaction, and in particular, the product of the oxidation reaction enters the reduction reaction system as a reactant to continue the reduction reaction with the cathode electrolyte, forming a two-stage series reaction system of oxidation reaction system-reduction reaction system.

[0017] The fifth mode: on the basis of the fourth mode, a set of electrolytic cell and oxidation reaction system are further added to form a three-stage series reaction system of oxidation reaction system-reduction reaction system-oxidation reaction system.

[0018] The off-site electro-catalytic reaction liquid of the application can be combined in multiple stages in series or in parallel outside the electrolytic cell according to the actual reaction process, in addition to the above-mentioned species connection mode.

[0019] Optionally, the anode electrolyte M with redox property in the anode electrolytic cell of the battery system x+ The oxidation reaction occurs on the surface of the anode to form the oxidation electrolyte M with oxidation potential (x+1)+ ;

[0020] The oxidation electrolyte M (x+1)+ enters the oxidation reaction system to occur oxidation reaction with the reactant I in the oxidation reaction system, and the oxidation electrolyte M (x+1)+ is reduced to obtain the anode electrolyte M x+ After separation, the anode electrolyte M x+ returns to the anode electrolytic cell to react with the anode again to form the oxidation electrolyte M with oxidation potential (x+1)+ ;

[0021] The cathode electrolyte in the battery system occurs redox reaction in the cathode electrolytic cell.

[0022] The above process of the application is the anode half-reaction process outside the electrolytic cell; M x+ , M (x+1)+ x in the formula is the valence state of M ion.

[0023] Optionally, the cathode electrolyte N with redox property in the cathode electrolytic cell of the battery system y+ The reduction reaction occurs on the surface of the cathode to form the reduction electrolyte N with reduction potential (y-1)+ ;

[0024] The reduction electrolyte N (y-1)+ enters the reduction reaction system to occur reduction reaction with the reactant II in the reduction reaction system, and the reduction electrolyte N (y-1)+ is oxidized to obtain the cathode electrolyte N y+ After separation, the cathode electrolyte N y+ returns to the cathode electrolytic cell to react with the cathode again to form the reduction electrolyte N with reduction potential (y-1)+ ;

[0025] The anode electrolyte in the battery system occurs redox reaction in the anode electrolytic cell.

[0026] The above process of the application is the cathode half-reaction process outside the electrolytic cell; N y+ , N (y-1)+Y in the formula is the valence of N ion.

[0027] Optionally, the battery system has an anode electrolyte M with redox property in the anode electrolytic cell x+ Oxidation reaction occurs on the surface of the anode to form an oxidation electrolyte M with oxidation potential (x+1)+ I;

[0028] The oxidation electrolyte M (x+1)+ I enters the oxidation reaction system I and reacts with the reactant I in the oxidation reaction system I, and the oxidation electrolyte M (x+1)+ I is reduced to obtain an anode electrolyte M x+ After separation, the anode electrolyte M x+ Returns to the anode electrolytic cell and reacts with the anode again to form an oxidation electrolyte M (x+1)+ with oxidation potential; cyclic oxidation-reduction process;

[0029] The battery system has a cathode electrolyte N with redox property in the cathode electrolytic cell y+ Reduction reaction occurs on the surface of the cathode to form a reduction electrolyte N with reduction potential (y-1)+ I;

[0030] The reduction electrolyte N (y-1)+ I enters the reduction reaction system I and reacts with the reactant II in the reduction reaction system I, and the reduction electrolyte N (y-1)+ I is oxidized to obtain a cathode electrolyte N y+ After separation, the cathode electrolyte N y+ Returns to the cathode electrolytic cell and reacts with the cathode again to form a reduction electrolyte N (y-1)+ with reduction potential; cyclic reduction-oxidation process.

[0031] In the above process of the application, the anode electrolyte circulates between the anode electrolytic cell and the oxidation reaction system and undergoes the processes of being reduced-oxidized-reduced-oxidized, and the reactant in the oxidation reaction system undergoes oxidation reaction; independently, the cathode electrolyte circulates between the cathode electrolytic cell and the reduction reaction system and undergoes the processes of being oxidized-reduced-oxidized-reduced, and the reactant in the reduction reaction system undergoes reduction reaction.

[0032] In the above-mentioned off-site electro-catalysis technology, the electrolytic cell system is used to prepare the medium with oxidation potential and the medium with reduction potential by electrolysis; then the medium with oxidation potential is introduced into the oxidation reactor to react with the reactants under the action of catalyst; and the medium with reduction potential is introduced into the reduction reactor to react with the reactants under the action of catalyst.

[0033] Optionally, the reaction product I of the oxidation reaction system I enters the reduction reaction system I as the reactant II of the reduction reaction system I and the reduction electrolyte N in the reduction reaction system I. (y-1)+ I to perform the reduction reaction I to obtain the reaction product II.

[0034] In the above-mentioned process, the oxidation reaction system and the reduction reaction system are connected in series, that is, the product of the oxidation reaction is used as the reactant of the reduction reaction system to continue the reaction.

[0035] Optionally, the reaction product II of the reduction reaction system I enters the oxidation reaction system I as the reactant III of the oxidation reaction system I to react with the oxidation electrolyte M in the oxidation reaction system I. (x+1)+ I to perform the oxidation reaction II to obtain the reaction product III.

[0036] In the above-mentioned process, when the first step of the oxidation reaction I is fast, the outlet of the reduction reaction system I and the inlet of the oxidation reaction system I are connected, and the reactant II in the oxidation reaction system I reacts with the oxidation electrolyte M. (x+1)+ I to perform the second oxidation reaction to obtain the reaction product III, and the process is a closed loop reaction.

[0037] Optionally, the reaction product II of the reduction reaction system I enters the oxidation reaction system II as the reactant III of the oxidation reaction system II to react with the oxidation electrolyte M in the oxidation reaction system II. (x+1)+ II to perform the oxidation reaction II to obtain the reaction product III.

[0038] In the above-mentioned process, when the first step of the oxidation reaction I is slow and the subsequent process continues, a new oxidation reaction system II can be connected behind the reduction reaction system I, and a new cell system II is connected, and the reactant II of the reduction reaction system reacts with the new oxidation electrolyte M in the new oxidation reaction system II. (x+1)+ II to perform the second oxidation reaction to obtain the reaction product III, and the process is an open loop reaction.

[0039] In the above process of the present application, the oxidation reaction system, the reduction reaction system and the multi-stage series connection of the oxidation reaction system are used to realize the matching of the chemical reaction process of oxidation, reduction and oxidation.

[0040] Optionally, the solute of the electrolyte comprises a redox ion pair; the redox ion pair is selected from at least one of inorganic metal ion pairs, organic metal ion pairs, organic pairs and inorganic pairs.

[0041] Optionally, the solvent of the electrolyte comprises at least one of an aqueous solution of an acid or a base, an organic solution and a water-organic compound solvent;

[0042] The acid is selected from inorganic acids and / or organic acids;

[0043] The concentration of the acid is 0.01-6 mol / L;

[0044] Preferably, the total concentration of the acid is 0.01-3 mol / L.

[0045] The inorganic acid is selected from at least one of H2SO4, HCl, H3PO4 and HClO4;

[0046] The organic acid is selected from at least one of acetic acid, trifluoroacetic acid and benzenesulfonic acid;

[0047] The organic solution is selected from at least one of methanol, methyl ether, acetonitrile, ethyl acetate, chloroform, dichloromethane and dimethyl sulfoxide.

[0048] The electrolyte can be added with alkali metals and the like to increase the conductivity of the electrolyte and optimize the catalytic activity, but is not limited to the above-mentioned metal inorganic salts;

[0049] Optionally, the solute of the anode electrolyte in the anode electrolysis cell comprises a redox ion pair I, the redox ion pair I is selected from at least one of I3 - / I - , Br2 / Br - , Fe(III) / Fe(II), [Fe(CN)6] 3- / [Fe(CN)6] 4- , VO2(I) / VO(II), Ce(IV) / Ce(III) and K2MnO4 / KMnO4.

[0050] Optionally, the solute of the cathode electrolyte in the cathode electrolysis cell comprises a redox ion pair II, the redox ion pair II is selected from at least one of inorganic metal ion pairs, organic metal ion pairs, organic pairs and inorganic pairs;

[0051] The inorganic metal ion pair is selected from at least one of Eu(II) / Eu(III), Cr(II) / Cr(III) and V(II) / V(III);

[0052] The organic metal ion pair is selected from at least one of organic ligand coordinated cobalt(II) / organic ligand coordinated cobalt(III), triethanolamine iron(II) / triethanolamine iron(III) and the like;

[0053] The organic pair is selected from at least one of quinone / phenol organic pair; preferably benzoquinone / hydroquinone, benzophenone / benzhydrol;

[0054] The inorganic pair is selected from heteropoly acid.

[0055] Optionally, the organic ligand coordinated cobalt(II) / organic ligand coordinated cobalt(III) is selected from porphyrin cobalt(II) / porphyrin cobalt(III);

[0056] The ion pair in the above-mentioned anode electrolyte of the present application is suitable for oxidation reaction with organic matter; the organic matter can be selected from at least one of oxygen-containing organic matter, nitrogen-containing organic matter, alkane, arene, alkene, alkyne, H2O, CO, H2S.

[0057] The ion pair in the above-mentioned cathode electrolyte of the present application is suitable for reduction reaction with organic matter; the organic matter can be selected from at least one of oxygen-containing organic matter, nitrogen-containing organic matter, nitrogen oxide, alkene, alkyne, arene, proton, CO2, CO, nitrogen.

[0058] Optionally, the reactant includes benzene, and the reaction product includes adipic acid.

[0059] Optionally, the reactant I of the oxidation reaction system I includes benzene, and the reaction product I includes phenol; the reactant II of the reduction reaction system I includes the phenol, and the reaction product II includes cyclohexanone.

[0060] Optionally, the reactant III includes cyclohexanone, and the reaction product III includes adipic acid.

[0061] In a second aspect, the present application provides an electrocatalytic reaction device for the above-mentioned off-site electrocatalytic reaction method, comprising:

[0062] A battery system for providing electrolyte with redox property;

[0063] A reaction system for providing reaction space for the electrolyte sent by the battery system and the reactant in the reaction system to carry out redox reaction;

[0064] A separation system for separating reaction product from electrolyte after redox reaction;

[0065] The liquid outlet of the battery system and the inlet of the reaction system are communicated;

[0066] The outlet of the reaction system and the inlet of the separation system are communicated;

[0067] The electrolyte outlet of the separation system and the liquid inlet of the battery system are communicated, and the separation system has a product outlet.

[0068] The battery system of the application is composed of an anode tank, a cathode tank, a diaphragm and the like, wherein the cathode chamber and the anode chamber are separated by an ion exchange membrane to avoid cross or penetration pollution of the anode and cathode electrolytes. The cathode and anode electrolytes are acidic water and / or organic compound. The solute of the anode is a medium M with redox property x+ , which undergoes oxidation reaction on the surface of the anode, and the valence state is increased, and the oxidation potential M (x+1)+ is obtained at this time; the solute of the cathode is a medium N with redox property y+ , which undergoes reduction reaction on the surface of the cathode, and the valence state is decreased, and the reduction potential N (y-1)+ is obtained at this time.

[0069] M (x+1)+ with the oxidation potential is introduced into another reactor to undergo oxidation reaction with a reactant, and the medium is reduced to generate M x+ , the medium and the reactant / product are separated, and then the medium returns to the anode tank again, and the electrochemical / catalytic reaction on the anode side is completed. In another spatially separated reactor, the reduced medium N (y-1)+ undergoes reduction reaction with a reactant, and the medium is oxidized to generate N y+ , the medium and the reactant / product are separated, and then the medium returns to the cathode tank again, and the electrochemical / catalytic reaction on the cathode side is completed.

[0070] In particular, for the "off-site" electrocatalytic tandem reaction technology, the reactant of the reduction reactor is the product of the oxidation reactor, which can also enter the oxidation reactor again to undergo oxidation reaction.

[0071] Optionally, the battery system comprises an H-type electrolytic cell, a flow battery or a diaphragm flow electrolytic cell without electrolyte.

[0072] Optionally, the flow battery comprises an anode electrolytic cell and a cathode electrolytic cell, and the anode and the cathode are each independently selected from at least one of carbon rod, carbon felt, titanium mesh and copper mesh.

[0073] Optionally, the surface of the anode and the cathode is each independently deposited with at least one of Pt, Pd, Bi, Ag and Pb metal.

[0074] The carbon rod, carbon felt, titanium mesh and copper mesh of the present application can be directly used as an anode or a cathode, or can be deposited with the above-mentioned metal on the surface thereof.

[0075] Optionally, the reaction system comprises an oxidation reactor and / or a reduction reactor; the separation system comprises an extractor and a rectifying column; the product outlet of the extractor is in communication with the inlet of the rectifying column, and the rectifying column has a product outlet.

[0076] Optionally, the liquid outlet of the anode electrolytic cell is in communication with the inlet of the oxidation reactor, the oxidation reactor is provided with reactants, the outlet of the oxidation reactor is in communication with the inlet of the extractor, the product outlet of the extractor is in communication with the inlet of the rectifying column, the electrolyte outlet of the extractor is in communication with the liquid inlet of the anode electrolytic cell, and the rectifying column has a product outlet.

[0077] Optionally, the liquid outlet of the cathode electrolytic cell is in communication with the inlet of the reduction reactor, the reduction reactor is provided with reactants, the outlet of the reduction reactor is in communication with the inlet of the extractor, the product outlet of the extractor is in communication with the inlet of the rectifying column, the electrolyte outlet of the extractor is in communication with the liquid inlet of the cathode electrolytic cell, and the rectifying column has a product outlet.

[0078] Optionally, the liquid outlet of the anode electrolytic cell I is in communication with the inlet of the oxidation reactor I, the oxidation reactor I is provided with reactants, the outlet of the oxidation reactor I is in communication with the inlet of the extractor I, the product outlet of the extractor I is in communication with the inlet of the rectifying column I, the electrolyte outlet of the extractor I is in communication with the liquid inlet of the anode electrolytic cell I; the product I outlet of the rectifying column I is in communication with the inlet of the reduction reactor, the liquid outlet of the cathode electrolytic cell is in communication with the inlet of the reduction reactor, the outlet of the reduction reactor is in communication with the inlet of the extractor II, the product outlet of the extractor II is in communication with the inlet of the rectifying column II, the electrolyte outlet of the extractor II is in communication with the liquid inlet of the cathode electrolytic cell, and the rectifying column II has a product II outlet.

[0079] Optionally, the product II outlet of the rectifying column II is in communication with the inlet of the oxidation reactor I;

[0080] Alternatively, the product II outlet of the rectifying column II is in communication with the inlet of the oxidation reactor II, the liquid outlet of the anode electrolytic cell II is in communication with the inlet of the oxidation reactor II; the outlet of the oxidation reactor II is in communication with the inlet of the extractor III, the product outlet of the extractor III is in communication with the inlet of the rectifying column III, the electrolyte outlet of the extractor III is in communication with the liquid inlet of the anode electrolytic cell II, and the rectifying column III has a product III outlet.

[0081] The electro-catalytic reaction method and the electro-catalytic reaction system can be used for preparing phenol from benzene, preparing cyclohexanone from phenol, preparing adipic acid from cyclohexanone or preparing adipic acid from benzene.

[0082] Optionally, the temperature of the battery system is 5-80℃, and the pressure is 1-30 bar.

[0083] Optionally, the oxidation reactor is selected from a fixed bed, a tank reactor, a slurry bed, a tray reactor or a fluidized bed reactor; the pressure of the oxidation reactor is 1-200 bar, and the temperature is 5-200℃.

[0084] Preferably, the pressure of the oxidation reactor is 1-20 bar, and the temperature is 15-50℃.

[0085] Optionally, no catalyst or optional catalyst I can be placed in the oxidation reactor, and the active component of the catalyst I is selected from at least one of Au, Cu, Ru, Ir, Pt, Pd, Rh, Fe, Co metal and oxides thereof; the catalyst I can be a supported type or directly used as metal particles.

[0086] Optionally, the catalyst can be directly at least one of carbide, phosphide, nitride and the like.

[0087] Optionally, the reactant in the oxidation reactor is selected from at least one of oxygen-containing organic matter, nitrogen-containing organic matter, alkane, arene, alkene, alkyne, H2O, CO, H2S.

[0088] Optionally, the reduction reactor is selected from a fixed bed, a tank reactor, a slurry bed reactor or a fluidized bed reactor; the pressure of the reduction reactor is 1-200 bar, and the temperature is 5-200℃.

[0089] Preferably, the pressure of the reduction reactor is 1-20 bar, and the temperature is 15-50℃.

[0090] Optionally, no catalyst or optional catalyst II can be placed in the reduction reactor, and the active component of the catalyst II is selected from at least one of Au, Cu, Ru, Ir, Pt, Pd, Rh, Fe, Co metal and oxides thereof; the catalyst I can be a supported type or directly used as metal particles.

[0091] Optionally, the catalyst can be directly at least one of carbide, phosphide, nitride and the like.

[0092] Optionally, the reactant in the reduction reactor is selected from at least one of oxygen-containing organic matter, nitrogen-containing organic matter, nitrogen oxide, alkene, alkyne, arene, proton, CO2, CO, nitrogen.

[0093] The whole electrocatalytic system of the present application comprises a battery system, an oxidation reactor, a reduction reactor, an extractor and a rectifying tower, etc. The products and oxidation-reduction medium of the oxidation reactor and the reduction reactor are separated by organic solvent extraction, and the oxidation-reduction medium returning to the anode tank and the cathode tank does not contain reactants and products, avoiding the pollution of the electrode, the diaphragm, etc. This method of separating the reactants and products from the electrode and the diaphragm, and connecting the oxidation reactor and the reduction reactor together, is the new electrocatalytic reaction technology proposed by the present application, which is called "off-site" electrocatalytic series reaction technology. This "off-site" electrocatalytic reaction system not only can be used for basic theoretical research in the laboratory, but also does not need to adjust the flow channel and internal structure process due to the amplification effect, and the oxidation and reduction reactors are very mature in industry and easy to amplify, so it can also be used for industrial testing at the scale of electrochemical demonstration, pilot test, application, etc.

[0094] Preferably, taking the production of adipic acid from benzene as an example, the step-by-step reaction process is as follows:

[0095] Anode tank: M x+ -e - →M (x+1)+ (1)

[0096] Cathode tank: N y+ +e - →N (y-1)+ (2)

[0097] Oxidation reactor: benzene + M (x+1)+ +H2O→phenol + M x+ +2H + (3)

[0098] Reduction reactor: phenol + 4N (y-1)+ +4H + →cyclohexanone + 4N y+ (4)

[0099] Oxidation reactor: cyclohexanone + M (x+1)+ +2H2O→adipic acid + M x+ +2H + (5)

[0100] Overall reaction: benzene + 4H2O→adipic acid + 2H2 (6)

[0101] The off-site electrocatalysis technology of the application can be applied to perform the benzene to adipic acid series reaction, and the oxidation reactor and the reduction reactor can be used separately. For example, the oxidation reactor performs oxidation reaction, and the reduction reactor performs hydrogen release experiment; conversely, the reduction reactor performs reduction reaction, and the oxidation reactor performs oxygen release experiment. The reactants of the oxidation reactor can be selected from at least one of oxygen-containing organic matter, nitrogen-containing organic matter, alkane, aromatic hydrocarbon, olefin, alkyne, H2O, CO, H2S and the like, but are not limited to these substances; the reactants in the reduction reactor can be selected from at least one of oxygen-containing organic matter, nitrogen-containing organic matter, nitrogen oxide, olefin, alkyne, aromatic hydrocarbon, proton, CO2, CO, nitrogen and the like, but are not limited to these substances. In addition, when the oxidation reactor uses H2O and the reduction reactor uses proton, the oxidation reactor produces oxygen, and the reduction reactor produces hydrogen, which is a double off-site water splitting process.

[0102] Compared with the prior art, the application has the following beneficial effects:

[0103] The application provides an off-site electrocatalysis series reaction system and an operating method, which transfers complex catalytic reaction from a traditional electrochemical reaction cell to a reactor outside the battery, avoids pollution of reactants or products to electrodes, diaphragms, catalysts and the like, ensures stable operation of the whole system, and has practical application value. At the same time, since the deactivation caused by the pollution of electrodes, diaphragms, catalysts and the like is avoided, the off-site electrocatalysis reaction technology can also be used for basic theoretical research, and the correlation between intrinsic catalytic activity and catalyst structure is obtained. The innovation of the battery reaction operating system of the application not only promotes the development of basic research, but also has practical application value, and can ensure stable operation and long-time operation of the battery reaction system. BRIEF DESCRIPTION OF DRAWINGS

[0104] Figure 1 The off-site electrocatalysis reaction method for the embodiments of the application is shown in the schematic diagram. DETAILED DESCRIPTION

[0105] The application will be further described below in combination with specific embodiments. The following description is only several embodiments of the application, and does not limit the application in any form. Although the preferred embodiments are disclosed as follows, the application is not limited thereto, and any skilled person in the art can make some changes or modifications to the disclosed technical contents without departing from the scope of the technical solution of the application, and the equivalent embodiments are also equivalent to the equivalent embodiments, which are within the scope of the technical solution.

[0106] Unless otherwise specified, the raw materials in the embodiments of the application are purchased through commercial channels and directly used without any special treatment.

[0107] Example 1 (Off-site electrocatalytic tandem process: benzene to adipic acid)

[0108] The specific experimental steps are as follows: a flow electrolysis cell was used, with solid graphite rods as the anode and cathode electrodes, and an H2SO4 solution of water and ethyl acetate mixed solvent (volume ratio 8:2) was used as the electrolyte (c H2SO4 = 3 mol / L) for both the anode and cathode, the ion pair for the anode was Ce(IV) / Ce(III), the molar concentration of Ce was 0.5 mol / L, the ion pair for the cathode was tetrahydrogen silicotungstic acid / hexahydrogen silicotungstic acid, the molar concentration of silicotungstic acid was 0.5 mol / L, and Nafion 117 (a commercialized diaphragm from DuPont) was used as the diaphragm.

[0109] S1: The reactant of the oxidation reactor was benzene, a tank reactor was used, the temperature was 25°C, a Ce(IV) solution and benzene (n 苯 :n Ce = 3:7) were simultaneously introduced into the reactor, the catalyst was RuO x / C. After 4 h of reaction, the water and ethyl acetate solvents were separated by the static method, at this time benzene and phenol were dissolved in ethyl acetate, the conversion rate of benzene was 99% and the selectivity of phenol was 98% by gas chromatography analysis, and the benzene raw material and phenol product were separated by a laboratory micro-distiller. The corresponding Ce(III) further entered the anode tank for oxidation regeneration.

[0110] S2: The phenol product and hexahydrogen silicotungstic acid were introduced into the reduction reactor, a tank reactor was used, the temperature was 25°C, the molar ratio of hexahydrogen silicotungstic acid solution and phenol was n 苯酚 :n 六氢型硅钨酸 = 1:3, and the catalyst was Pd / C. After 1 h of reaction, the water and ethyl acetate solvents were separated by the static method, at this time phenol and cyclohexanone were dissolved in ethyl acetate, the conversion rate of phenol was 60% and the selectivity of cyclohexanone was 92% by gas chromatography analysis, and the phenol and cyclohexanone were separated by a laboratory micro-distiller. The corresponding tetrahydrogen silicotungstic acid further entered the cathode tank for reduction regeneration.

[0111] S3: Then, the cyclohexanone was introduced into the oxidation reactor (returned to the system in S1), a tank reactor was used, the temperature was 40°C, a Ce(IV) solution and cyclohexanone (n 环己酮 :n Ce= 1 : 7) were simultaneously fed into the reactor, after stirring for 2 h, the water and ethyl acetate solvent were separated by static method, at this time the cyclohexanone and adipic acid were dissolved in ethyl acetate, the conversion of cyclohexanone was >99% and the selectivity of adipic acid was 100% by liquid chromatography analysis, because adipic acid was slightly soluble in water and soluble in ethyl acetate, the adipic acid was obtained by distillation to remove ethyl acetate, the purity of the product was 99%. The corresponding generated Ce(III) was further oxidized and regenerated in the anode tank.

[0112] Example 2 (Phenol oxidation from benzene in off-site electrocatalytic tandem method)

[0113] The step of Example 2 was the same as Example 1, and this example was the activity optimization process of phenol from benzene, the specific process was as follows; the reactant of the oxidation reactor was benzene, a kettle reactor was used, the temperature was 25°C, the molar ratio of different oxidation-reduction medium solutions and benzene (n 苯 :n 媒介体 = 2 : 8) were simultaneously fed into the oxidation reactor, 10% trifluoroacetic acid was added to promote the generation of phenol, and the catalyst was RuO x / C. After 1 h of reaction, the water and ethyl acetate solvent were separated by static method, at this time the benzene and phenol were dissolved in ethyl acetate, the conversion of benzene and the selectivity of phenol were obtained by gas chromatography analysis, and the benzene raw material and phenol product were separated by a laboratory micro-distiller. The corresponding oxidation-reduction medium was further oxidized and regenerated in the anode tank. The benzene conversion and phenol selectivity under different oxidation-reduction media were shown in Table 1.

[0114] Table 1. Benzene conversion and phenol selectivity under different oxidation-reduction media

[0115]

[0116] Note: The utilization rate of the electron medium is the percentage of the electrons transferred to the product.

[0117] Example 3 (Phenol reduction to cyclohexanone in off-site electrocatalytic tandem method)

[0118] The step of Example 3 was the same as Example 1, and this example was the activity optimization process of phenol reduction to cyclohexanone; the specific process was as follows; the phenol product and oxidation-reduction medium were fed into the reduction reactor, a kettle reactor was used, the temperature was 25°C, the molar ratio of phenol and oxidation-reduction medium solution was n 苯酚 :n 媒介体= 1 : 3 or 1 : 5, the catalyst is Pd / C, and the catalyst surface is grafted with n-octanol to adjust the hydrophilic and hydrophobic properties of the catalyst surface, thereby adjusting the catalytic activity. After 1 h of reaction, the water and the ethyl acetate solvent are separated by the static method, at which point the phenol and the cyclohexanone are dissolved in the ethyl acetate, and the conversion rate of the phenol and the selectivity of the cyclohexanone are obtained by the gas chromatography analysis method. The phenol and the cyclohexanone are separated by a laboratory micro-distiller. The corresponding oxidized redox mediator further enters the cathode tank for reduction regeneration. The phenol conversion and the cyclohexanone selectivity under different redox mediators are shown in Table 2 below.

[0119] Table 2. Phenol conversion rate and cyclohexanone selectivity under different redox mediators

[0120]

[0121] Note: The electron mediator utilization rate is the percentage of the electrons transferred to the product.

[0122] Example 4 (Cyclohexanone oxidation to adipic acid in the off-site electrocatalytic tandem method)

[0123] The step of Example 4 is the same as that of Example 1, and this example is an activity optimization process for cyclohexanone oxidation to adipic acid. The specific process is as follows: cyclohexanone and redox mediator are introduced into the oxidation reactor, a kettle reactor is used, the temperature is 40°C, the molar ratio of cyclohexanone to redox mediator solution is n 环己酮 : n 媒介体 = 1 : 7, after stirring for 2 h, the water and the organic solvent are separated by the static method, at which point the cyclohexanone and the adipic acid are dissolved in the organic solvent, and the conversion rate of the cyclohexanone and the selectivity of the adipic acid are obtained by the liquid chromatography analysis method. Because the adipic acid is slightly soluble in water and soluble in solvents such as ethyl acetate, ethyl acetate is used as the extractant, and the adipic acid can be obtained by removing the ethyl acetate by distillation, and the product purity is not less than 99%. The corresponding generated reduced state redox electron mediator further enters the anode tank for oxidation regeneration. The cyclohexanone conversion and the adipic acid selectivity under different redox mediators are shown in Table 3 below.

[0124] Table 3. Cyclohexanone conversion rate and adipic acid selectivity under different redox mediators

[0125]

[0126] Note: The electron mediator utilization rate is the percentage of the electrons transferred to the product.

[0127] As Figure 1As shown, the reaction systems of embodiments 1-4 of the present application can successfully realize the production of adipic acid from benzene, and the yield of intermediate products, final products and conversion effect have reached the practical use requirements. The electro-catalytic system of embodiments 1-4 of the present application comprises a battery system, an oxidation reactor, a reduction reactor, an extractor and a rectifying tower, etc. The products and oxidation-reduction medium of the oxidation reactor and the reduction reactor are separated by organic solvent extraction, and the oxidation-reduction medium returned to the anode tank and the cathode tank does not contain reactants and products, avoiding the pollution of the electrode, the diaphragm, etc. This method of separating the reactants and products from the electrode and the diaphragm, and connecting the oxidation reactor and the reduction reactor together is the new electro-catalytic reaction technology proposed by the present application, which is called "off-site" electro-catalytic series reaction technology. This "off-site" electro-catalytic reaction system not only can be used for basic theoretical research in the laboratory, but also does not need to adjust the flow channel and internal structure process due to the amplification effect of the battery, and the oxidation and reduction reactors are very mature in industry and easy to amplify, so it can also be used for industrial testing at the scale of electrochemical demonstration, pilot test, application, etc.

[0128] The above is only a few embodiments of the present application, and does not limit the present application in any form. Although the preferred embodiments are disclosed above, the present application is not limited thereto. Any person skilled in the art can make some changes or modifications to the above disclosed technical contents without departing from the scope of the present application, and such changes or modifications are equivalent to equivalent embodiments, and all of them are within the scope of the technical solution.

Claims

1. A method of anodic electrocatalytic reaction, characterized in that, The off-leave electro-catalytic reaction method comprises the following steps: The electrolyte ions in the battery system exchange electrons with the electrode to obtain oxidation potential or reduction potential; the electrolyte with oxidation potential or reduction potential enters the independent reaction system outside the battery system, and performs oxidation-reduction reaction with the reactants in the reaction system to obtain a mixture containing reaction products, and after separation, the electrolyte after the oxidation-reduction reaction returns to the battery system to obtain oxidation potential or reduction potential again; The battery system has an anolyte M with redox properties in the anode electrolytic cell x+ An oxidation reaction occurs on the anode surface, forming an oxidized electrolyte M with an oxidation potential (x+1)+ I; The oxidizing electrolyte M (x+1)+ I enters an oxidation reaction system I, and reacts with a reactant I in the oxidation reaction system I, and the reactant I is oxidized to obtain a reaction product I, and the oxidizing electrolyte M (x+1)+ I is reduced to obtain an anode electrolyte M x+ , after separation, the anode electrolyte M x+ returns to the anode electrolytic cell, and reacts with the anode again to form the oxidizing electrolyte M (x+1)+ with an oxidation potential; The battery system has a catholyte N with redox properties in the cathode electrolytic cell y+ A reduction reaction occurs at the cathode surface, forming a reduced electrolyte N with a reduction potential (y-1)+ I; The reducing electrolyte N (y-1)+ I enters the reducing reaction system I, and reacts with the reactant II of the reducing reaction system I, and the reactant II is reduced to obtain the reaction product II, and the reducing electrolyte N (y-1)+ I is oxidized to obtain the cathode electrolyte N y+ , after separation, the cathode electrolyte N y+ returns to the cathode electrolysis cell, and reacts with the cathode again to form the reducing electrolyte N (y-1)+ with a reducing potential; The reaction product I of the oxidation reaction system I enters the reduction reaction system I as a reactant II of the reduction reaction system I and the reducing electrolyte N in the reduction reaction system I (y-1)+ I performs a reduction reaction I to obtain the reaction product II; The reaction product II of the reduction reaction system I enters the oxidation reaction system I as a reactant III of the oxidation reaction system I, and reacts with the oxidizing electrolyte M in the oxidation reaction system I (x+1)+ I to obtain the reaction product III; The reactant I of the oxidation reaction system I comprises benzene, and the reaction product I comprises phenol; the reactant II of the reduction reaction system I comprises the phenol, and the reaction product II comprises cyclohexanone; The reactant III comprises cyclohexanone, and the reaction product III comprises adipic acid.

2. A method of electrocatalytic reaction for leaving according to claim 1, characterized in that, The reaction product II of the reduction reaction system I enters an oxidation reaction system II as a reactant III of the oxidation reaction system II, and reacts with an oxidizing electrolyte M in the oxidation reaction system II (x+1)+ II to obtain the reaction product III.

3. The method of claim 1, wherein the method is a method of off-chip electrocatalytic reactions. The solute of the electrolyte comprises at least one of inorganic metal ion pairs, organic metal ion pairs, organic pairs and inorganic pairs.

4. The method of claim 1, wherein the method is a method of off-chip electrocatalytic reactions. The solvent of the electrolyte comprises at least one of aqueous solution of acid or base, organic solution and water and organic compound solvent; The acid is selected from inorganic acid and / or organic acid; The concentration of the acid is 0.01-6 mol / L; The inorganic acid is selected from at least one of H2SO4, HCl, H3PO4 and HClO4; The organic acid is selected from at least one of acetic acid, trifluoroacetic acid and benzenesulfonic acid; The organic solution is selected from at least one of methanol, methyl ether, acetonitrile, ethyl acetate, chloroform, dichloromethane and dimethyl sulfoxide.

5. The method of claim 1, wherein the method is a method of off-chip electrocatalytic reactions. The solute of the anolyte in the anode electrolysis cell comprises a redox ion pair I selected from the group consisting of I3 - / I - , Br2 / Br - , Fe(III) / Fe(II), [Fe(CN)6] 3- / [Fe(CN)6] 4- , VO2(I) / VO(II), Ce(IV) / Ce(III) and at least one of K2MnO4 / KMnO4.

6. The method of claim 1, wherein the method is a method of off-chip electrocatalytic reactions. The solute of the cathode electrolyte in the cathode electrolysis cell comprises redox ion pair II, and the redox ion pair II is selected from at least one of inorganic metal ion pairs, organic metal ion pairs, organic pairs and inorganic pairs; The inorganic metal ion pair is selected from at least one of Eu(II) / Eu(III), Cr(II) / Cr(III) and V(II) / V(III); The organic metal ion pair is selected from at least one of organic ligand cobalt(II) / organic ligand cobalt(III) and triethanolamine iron(II) / triethanolamine iron(III); The organic pair is selected from at least one of benzoquinone / hydroquinone and benzophenone / benzhydrol; The inorganic pair is selected from heteropoly acid.

7. An electrocatalytic reaction device for use in the electrocatalytic reaction method according to any one of claims 1 to 6, characterized by comprising: The electro-catalytic reaction device comprises: A battery system for providing electrolyte with redox property; A reaction system for providing reaction space for the electrolyte sent by the battery system and the reactants in the reaction system to perform oxidation-reduction reaction; A separation system for separating reaction products and electrolyte after oxidation-reduction reaction; The liquid outlet of the battery system and the inlet of the reaction system are communicated; The outlet of the reaction system and the inlet of the separation system are communicated; The electrolyte outlet of the separation system and the liquid inlet of the battery system are communicated, and the separation system has a product outlet; The battery system comprises H-type electrolysis cell, flow battery or electrolyte-free diaphragm flow electrolysis cell; The flow battery comprises an anode electrolytic cell and a cathode electrolytic cell, and the anode and the cathode are each independently selected from at least one of carbon rod, carbon felt, titanium mesh and copper mesh; The reaction system comprises an oxidation reactor and / or a reduction reactor; the separation system comprises an extractor and a rectifying tower; the product outlet of the extractor is in communication with the inlet of the rectifying tower, and the rectifying tower has a product outlet; The liquid outlet of the anode electrolytic cell is in communication with the inlet of the oxidation reactor, the oxidation reactor is provided with reactants, the outlet of the oxidation reactor is in communication with the inlet of the extractor, the product outlet of the extractor is in communication with the inlet of the rectifying tower, the electrolyte outlet of the extractor is in communication with the liquid inlet of the anode electrolytic cell, and the rectifying tower has a product outlet; The liquid outlet of the cathode electrolytic cell is in communication with the inlet of the reduction reactor, the reduction reactor is provided with reactants, the outlet of the reduction reactor is in communication with the inlet of the extractor, the product outlet of the extractor is in communication with the inlet of the rectifying tower, the electrolyte outlet of the extractor is in communication with the liquid inlet of the cathode electrolytic cell, and the rectifying tower has a product outlet; The liquid outlet of the anode electrolytic cell I is in communication with the inlet of the oxidation reactor I, the oxidation reactor I is provided with reactants, the outlet of the oxidation reactor I is in communication with the inlet of the extractor I, the product outlet of the extractor I is in communication with the inlet of the rectifying tower I, the electrolyte outlet of the extractor I is in communication with the liquid inlet of the anode electrolytic cell I; the product I outlet of the rectifying tower I is in communication with the inlet of the reduction reactor, the liquid outlet of the cathode electrolytic cell is in communication with the inlet of the reduction reactor, the outlet of the reduction reactor is in communication with the inlet of the extractor II, the product outlet of the extractor II is in communication with the inlet of the rectifying tower II, the electrolyte outlet of the extractor II is in communication with the liquid inlet of the cathode electrolytic cell, and the rectifying tower II has a product II outlet.

8. The electro-catalytic reaction device according to claim 7, wherein The surface of the anode and the cathode is each independently deposited with at least one of Pt, Pd, Bi, Ag and Pb metal.

9. The electro-catalytic reaction device according to claim 7, wherein The product II outlet of the rectifying tower II is in communication with the inlet of the oxidation reactor I.

10. The electro-catalytic reaction device of claim 7, wherein, The product II outlet of the rectifying tower II is in communication with the inlet of the oxidation reactor II, the liquid outlet of the anode electrolytic cell II is in communication with the inlet of the oxidation reactor II; the outlet of the oxidation reactor II is in communication with the inlet of the extractor III, the product outlet of the extractor III is in communication with the inlet of the rectifying tower III, the electrolyte outlet of the extractor III is in communication with the liquid inlet of the anode electrolytic cell II, and the rectifying tower III has a product III outlet.

11. The electro-catalytic reaction device of claim 7, wherein, The oxidation reactor is selected from a fixed bed, a tank reactor, a slurry bed, a tray reactor or a fluidized bed reactor; the pressure of the oxidation reactor is 1-200 bar, and the temperature is 5-200 ℃. The active component of the catalyst I placed in the oxidation reactor is selected from at least one of Au, Cu, Ru, Ir, Pt, Pd, Rh, Fe, Co metals and oxides thereof; The reactants in the oxidation reactor are selected from at least one of oxygen-containing organic matter, nitrogen-containing organic matter, alkane, arene, alkene, alkyne, H2O, CO, H2S.

12. The electro-catalytic reaction device of claim 7, wherein, The reduction reactor is selected from a fixed bed, a tank reactor, a slurry bed reactor or a fluidized bed reactor; the pressure of the reduction reactor is 1-200 bar, and the temperature is 5-200 ℃; The active component of the catalyst II placed in the reduction reactor is selected from at least one of Au, Cu, Ru, Ir, Pt, Pd, Rh, Fe, Co metals and oxides thereof; The reactants in the reduction reactor are selected from at least one of oxygen-containing organic matter, nitrogen-containing organic matter, nitrogen-oxygen compound, alkene, alkyne, arene, proton, CO2, CO, nitrogen.

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