An integrated membrane electrode and a preparation method thereof and a device for directional reduction-oxidation regulation synthesis of hydrogen peroxide by anthraquinone derivatives

Abstract

The application provides an integrated membrane electrode and a preparation method thereof and a device for directional reduction and oxidation regulation synthesis of hydrogen peroxide of anthraquinone derivative compounds, and relates to the technical field of electrocatalysis. The preparation method of the integrated membrane electrode comprises the following steps: mixing a cathode catalyst, a first perfluorosulfonic acid resin solution and a first mixed solvent to obtain a cathode catalyst slurry; mixing an anode catalyst, a second perfluorosulfonic acid resin solution and a second mixed solvent to obtain an anode catalyst slurry; and spraying the cathode / anode catalyst slurry on both sides of a proton exchange membrane respectively to obtain the integrated membrane electrode. The membrane electrode is used in the device for directional reduction and oxidation regulation synthesis of hydrogen peroxide of anthraquinone derivative compounds, water is used as a hydrogen source without using hydrogen, the steam methane reforming process with large scale and high energy consumption is avoided, hydrogen is added in a directional manner, hydrogen peroxide is generated by re-oxidation, and the hydrogen peroxide is not affected by oxygen mass transfer; and the device has the advantages of small reactor area, short process, no secondary pollution and the like.

Description

Technical Field

[0001] This invention relates to the field of electrocatalysis technology, and in particular to an integrated membrane electrode and its preparation method, as well as an apparatus for the directed reduction and oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide. Background Technology

[0002] Hydrogen peroxide (H2O2) is an environmentally friendly oxidant widely used in medical and health, chemical industries, and environmental remediation. The anthraquinone oxidation process is currently the main method for industrial H2O2 production. Hydrogen and anthraquinone compounds are used as basic raw materials. Alkyl anthraquinone precursors dissolved in an organic solvent mixture undergo catalytic hydrogenation, followed by an oxidation step to obtain an H2O2 solution. More than 95% of commercially produced H2O2 worldwide originates from this process. However, the hydrogenation stage in the anthraquinone process requires high-purity (99%) hydrogen to avoid catalyst poisoning or increased side reactions, posing safety risks. This high-purity hydrogen is typically obtained from steam methane reforming, a high-temperature, capital-intensive process that is difficult to scale up and consumes a large amount of energy. Therefore, further exploration and development of greener, more efficient, and environmentally friendly new methods for H2O2 preparation are needed.

[0003] As an alternative, the production of H2O2 based on the O2 electrochemical reduction reaction (ORR) has attracted considerable attention due to its environmental friendliness and cost-effectiveness. H2O2 electrosynthesis relies on the preparation of high-performance electrodes with excellent product selectivity and stability. To date, many materials, such as noble metals and their alloys, single-atom catalysts, and carbon-based materials, have been selected due to their effectiveness in... The OOH intermediate exhibits moderate binding capacity, thus demonstrating excellent 2e-type properties. - ORR selectivity. However, due to the low solubility and low diffusivity of O2 in solution, ORR is greatly limited by oxygen mass transfer.

[0004] In summary, those skilled in the art urgently need to develop a highly efficient method for synthesizing H2O2 that combines an electrochemical anthraquinone hydrogenation device with phase transfer catalysis. Summary of the Invention

[0005] The purpose of this invention is to provide an integrated membrane electrode and its preparation method, as well as an apparatus for the directed reduction and oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide, in order to solve the problems of high cost and poor oxygen mass transfer in the production of hydrogen peroxide.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] This invention provides a method for fabricating an integrated membrane electrode, comprising the following steps:

[0008] 1) The cathode catalyst, the first perfluorosulfonic acid resin solution, and the first mixed solvent are mixed to obtain a cathode catalyst slurry;

[0009] 2) The anode catalyst, the second perfluorosulfonic acid resin solution, and the second mixed solvent are mixed to obtain the anode catalyst slurry;

[0010] 3) The cathode catalyst slurry and the anode catalyst slurry are sprayed onto both sides of the proton exchange membrane to obtain an integrated membrane electrode with a cathode catalyst layer and an anode catalyst layer loaded.

[0011] There is no order requirement for steps 1 and 2).

[0012] Preferably, the cathode catalyst in step 1) is palladium nanoparticles and / or palladium carbon nanoparticles;

[0013] The mass fraction of the first perfluorosulfonic acid resin solution is 3-20%;

[0014] The mass ratio of the cathode catalyst to the perfluorosulfonic acid resin in the first perfluorosulfonic acid resin solution is 1:1~5.

[0015] Preferably, the anode catalyst in step 2) is nano-iridium oxide particles;

[0016] The mass fraction of the second perfluorosulfonic acid resin solution is 3-20%;

[0017] The mass ratio of the anode catalyst to the perfluorosulfonic acid resin in the second perfluorosulfonic acid resin solution is 1:1~2.

[0018] Preferably, the proton exchange membrane in step 3) is a perfluorosulfonic acid proton exchange membrane with a thickness of 50~200μm;

[0019] The cathode catalyst is loaded onto the proton exchange membrane at a rate of 0.5~5 mg / cm³. -2 ;

[0020] The loading of the anode catalyst on the proton exchange membrane is 0.5~5 mg cm⁻¹. -2 .

[0021] Another object of the present invention is to provide an integrated membrane electrode prepared by a method for preparing an integrated membrane electrode.

[0022] Another objective of this invention is to provide an apparatus for the directed reduction-oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide, the apparatus comprising an anode storage tank, a reactor, a cathode circulating storage tank, a mixing reaction tank, a first regulating flow divider, an oxidation tank, a second regulating flow divider, and a hydrogen peroxide storage tank.

[0023] The reactor stack includes an anode end plate, a first gasket, an anode current collector, a second gasket, an anode current guide plate, an integrated membrane electrode, a cathode current guide plate, a third gasket, a cathode current collector, a fourth gasket, and a cathode end plate, which are stacked sequentially.

[0024] The integrated membrane electrode is the integrated membrane electrode described above;

[0025] The anode guide plate and the integrated membrane electrode form an anode cavity, which is provided with an anode inlet and an anode outlet; the cathode guide plate and the integrated membrane electrode form a cathode cavity, which is provided with a cathode inlet and a cathode outlet.

[0026] The cathode circulating liquid storage tank is connected to the cathode inlet, and the cathode outlet is sequentially connected to the mixing reaction tank and the first regulating and diverting tank; the first regulating and diverting tank is connected to the cathode circulating liquid storage tank and the oxidation tank respectively.

[0027] The anode storage tank is connected to the anode inlet, and the anode outlet is sequentially connected to the oxidation tank and the second regulating and diverting tank; the second regulating and diverting tank is connected to the mixing reaction tank and the hydrogen peroxide storage tank respectively.

[0028] Preferably, the mixing reaction tank is a cylindrical internal circulation reaction tank, which includes a top water inlet, a screw ribbon agitator and a bottom water outlet.

[0029] Both the first regulating diversion tank and the second regulating diversion tank are right trapezoids with an inclination angle of 30~90°.

[0030] Preferably, the oxidation tank is a cylindrical oxidation reaction tank, which includes an inlet, a gas-liquid distribution plate, a stirrer and an outlet. The gas-liquid distribution plate includes multiple staggered gas channels and liquid channels. The gas channels are equipped with microporous aeration discs, and the liquid channels are equipped with water distribution plates with a pore size of 0.1~0.5mm, so that the oxygen flowing into the oxidation tank is evenly distributed.

[0031] Another object of the present invention is to provide an application of an apparatus for the directed reduction-oxidation regulation of anthraquinone-derived compounds in the synthesis of hydrogen peroxide, comprising the following steps:

[0032] S1. Connect the positive and negative terminals of the reactor to a DC regulated power supply, add pure water to the anode storage tank, and add anthraquinone derivatives to the cathode circulating storage tank;

[0033] 1-Hexanol was added as a solvent and tetrabutylammonium chloride as an organic ligand to the mixing reaction tank;

[0034] The anthraquinone-derived compound is an anthraquinone-derived sodium salt solution;

[0035] S2. Pure water in the anode storage tank is introduced into the anode inlet of the reactor, while anthraquinone-derived sodium salt solution in the cathode circulation storage tank is introduced into the cathode inlet of the reactor.

[0036] S3. Start the DC regulated power supply to begin electrolysis. The oxygen and pure water generated at the anode enter the oxidation tank, and the hydrogenated anthraquinone-derived sodium salt solution generated at the cathode enters the mixed reaction tank.

[0037] S4. The sodium salt solution of hydrogenated anthraquinone derivative reacts in a mixed reaction tank to obtain a mixed reaction liquid containing hydrogenated anthraquinone derivative ammonium salt compounds. This mixed reaction liquid is then introduced into the first regulating and splitting tank. After separation in the first regulating and splitting tank, an aqueous phase containing anthraquinone derivative sodium salt and an organic phase containing hydrogenated anthraquinone derivative ammonium salt compounds are obtained. The aqueous phase is introduced into the cathode circulating storage tank, and the organic phase containing hydrogenated anthraquinone derivative ammonium salt compounds is introduced into the oxidation tank.

[0038] S5. In the oxidation tank, hydrogenated anthraquinone-derived ammonium salt compounds react with oxygen to obtain a mixed reaction liquid containing hydrogen peroxide, which is then introduced into the second regulating and diverting tank to obtain an aqueous phase containing hydrogen peroxide and an organic phase of anthraquinone-derived ammonium salt compounds regenerated after the reaction; wherein, the aqueous phase is introduced into the hydrogen peroxide storage tank, and the organic phase is introduced into the mixed reaction tank.

[0039] Preferably, the current density of the DC regulated power supply is 20~200 mA cm⁻¹. -2 ;

[0040] The anthraquinone-derived sodium salt includes one or more of sodium anthraquinone sulfonate, sodium anthraquinone-2-sulfonate, sodium anthraquinone-1,5-disulfonate, and sodium 1-aminoanthraquinone-2-sulfonate.

[0041] The concentration of the anthraquinone-derived sodium salt solution in step S1 is 0.1~0.5 mol / L.

[0042] The present invention has at least the following beneficial effects:

[0043] This invention prepares an integrated membrane electrode and utilizes it to design a device for the directed reduction and oxidation of anthraquinone-derived compounds to synthesize hydrogen peroxide. Using water as the hydrogen source, it avoids the need for large-scale, energy-intensive steam methane reforming processes, offering advantages such as small reactor footprint, short process flow, and no secondary pollution. Compared to electrocatalytic oxygen reduction methods, which are greatly limited by the low solubility and diffusion of oxygen in solution, this invention uses a directed hydrogenation reaction followed by oxidation to produce H₂O₂, unaffected by oxygen mass transfer. The device uses water and oxygen as raw materials, recycling organic materials, resulting in lower costs and an environmentally friendly approach. Attached Figure Description

[0044] Figure 1This is a schematic diagram of the apparatus used in the present invention for the directed reduction and oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide;

[0045] The components include: 1. Anode storage tank; 2. Anode metering pump; 3. Anode electromagnetic flowmeter; 4. Integrated membrane electrode; 5. Reactor stack; 6. Cathode circulating storage tank; 7. Cathode metering pump; 8. Cathode electromagnetic flowmeter; 9. Mixing reaction tank; 10. First regulating and diverting tank; 11. Aqueous phase circulation unit metering pump; 12. Aqueous phase circulation unit electromagnetic flowmeter; 13. Oxidation tank metering pump; 14. Oxidation tank electromagnetic flowmeter; 15. Oxidation tank; 16. Second regulating and diverting tank; 17. Organic phase circulation unit metering pump; 18. Organic phase circulation unit electromagnetic flowmeter; 19. Hydrogen peroxide metering pump; 20. Hydrogen peroxide electromagnetic flowmeter; and 21. Hydrogen peroxide storage tank.

[0046] Figure 2 This is a schematic diagram of the reactor stack in this invention;

[0047] Among them, 501 is the anode end plate, 502 is the first gasket, 503 is the anode current collector, 504 is the second gasket, 505 is the anode current guide plate, 4 is the integrated membrane electrode, 507 is the cathode current guide plate, 508 is the third gasket, 509 is the cathode current collector, 510 is the fourth gasket, and 511 is the cathode end plate.

[0048] Figure 3 This is a schematic diagram illustrating the mechanism of electrocatalytic reduction of anthraquinone-derived sodium salt compounds in hydrogenated water occurring within the reactor stack of this invention, wherein H... ads For the adsorption of hydrogen;

[0049] Figure 4 This is a schematic diagram of the structure of the first regulating diversion tank and the second regulating diversion tank in this invention;

[0050] Figure 5 A schematic diagram of an electrochemical reaction apparatus for the electrocatalytic reduction of sodium anthraquinone sulfonate in hydrogenated water;

[0051] Figure 6 The graph shows the cumulative concentration of sodium anthraquinone sulfonate and the Faraday efficiency over time when the integrated membrane electrode prepared in Example 1 electrocatalytically reduces sodium anthraquinone sulfonate in hydrogenated water.

[0052] Figure 7 This is a statistical graph showing the change in the conversion rate of sodium anthraquinone sulfonate over time when the integrated membrane electrode prepared in Example 1 is used for the electrocatalytic reduction of sodium anthraquinone sulfonate in hydrogenated water.

[0053] Figure 8 A schematic diagram of an apparatus for the phase transfer of sodium anthraquinone sulfonate and its hydrides;

[0054] Figure 9A statistical graph showing the phase transfer coefficients of sodium anthraquinone sulfonate and sodium anthraquinone sulfonate when different concentrations of tetrabutylammonium chloride are added to a mixing reaction tank.

[0055] Figure 10 This is a statistical chart showing the concentration of hydrogen peroxide in the water produced during the preparation of hydrogen peroxide in step (3) of Example 1;

[0056] Figure 11 This is a full-spectral absorbance scan of the hydrogen peroxide effluent during the preparation of hydrogen peroxide in step (3) of Example 1. Detailed Implementation

[0057] This invention provides a method for fabricating an integrated membrane electrode, comprising the following steps:

[0058] 1) The cathode catalyst, the first perfluorosulfonic acid resin solution, and the first mixed solvent are mixed to obtain a cathode catalyst slurry;

[0059] 2) The anode catalyst, the second perfluorosulfonic acid resin solution, and the second mixed solvent are mixed to obtain the anode catalyst slurry;

[0060] 3) The cathode catalyst slurry and the anode catalyst slurry are sprayed onto both sides of the proton exchange membrane to obtain an integrated membrane electrode with a cathode catalyst layer and an anode catalyst layer loaded.

[0061] There is no order requirement for steps 1 and 2).

[0062] In this invention, the cathode catalyst in step 1) is palladium nanoparticles and / or palladium carbon nanoparticles.

[0063] In this invention, the first mixed solvent is a mixture of water and alcohol, wherein the alcohol is ethanol and / or isopropanol, and the mass ratio of water to alcohol is 1:1 to 5, preferably 1:2 to 4, more preferably 1:2.5 to 3.5, and more preferably 1:3.

[0064] In this invention, the second mixed solvent is a mixture of water and alcohol, wherein the alcohol is ethanol and / or isopropanol, and the mass ratio of water to alcohol is 1:1 to 5, preferably 1:2 to 4, more preferably 1:2.5 to 3.5, and more preferably 1:3.

[0065] In this invention, the mass fraction of the first perfluorosulfonic acid resin solution is 3-20%, specifically 5%, 8%, 10%, 12%, 15%, 16%, or 18%.

[0066] In this invention, the mass ratio of the cathode catalyst to the perfluorosulfonic acid resin in the first perfluorosulfonic acid resin solution is 1:1 to 5, preferably 1:2 to 4, more preferably 1:2.5 to 3.5, and even more preferably 1:3.

[0067] In this invention, the anode catalyst in step 2) is nano-iridium oxide particles.

[0068] In this invention, the mass fraction of the second perfluorosulfonic acid resin solution is 3-20%, specifically 5%, 8%, 10%, 12%, 15%, 16%, or 18%.

[0069] In this invention, the mass ratio of the anode catalyst to the perfluorosulfonic acid resin in the second perfluorosulfonic acid resin solution is 1:1~2, preferably 1:1.2~1.8, more preferably 1:1.4~1.6, and even more preferably 1:1.5.

[0070] In this invention, the proton exchange membrane in step 3) is a perfluorosulfonic acid proton exchange membrane with a thickness of 50~200μm, preferably 70~180μm, more preferably 90~150μm, and even more preferably 110~130μm.

[0071] In this invention, the loading of the cathode catalyst on the proton exchange membrane is 0.5~5 mg cm⁻¹. -2 Preferably 0.6~4mg cm -2 More preferably 0.8~3mg cm -2 More preferably 1~2 mg cm -2 The optimal value is 1 mg cm -2 .

[0072] In this invention, the loading of the anode catalyst on the proton exchange membrane is 0.5~5 mg cm⁻¹. -2 Preferably 0.5~4mg cm -2 More preferably 0.5~2mg cm -2 More preferably 0.5~1mg cm -2 The optimal value is 0.5 mg cm -2 .

[0073] This invention provides an integrated membrane electrode prepared by the above-described preparation method.

[0074] This invention provides an apparatus for the directed reductive oxidation-regulated synthesis of hydrogen peroxide from anthraquinone-derived compounds, such as... Figure 1As shown, the apparatus for the directed reduction and oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide includes an anode storage tank 1, an anode metering pump 2, an anode electromagnetic flowmeter 3, a reactor 5, a cathode circulating storage tank 6, a cathode metering pump 7, a cathode electromagnetic flowmeter 8, a mixing reaction tank 9, a first regulating and diverting tank 10, an aqueous phase circulation unit metering pump 11, an aqueous phase circulation unit electromagnetic flowmeter 12, an oxidation tank metering pump 13, an oxidation tank electromagnetic flowmeter 14, an oxidation tank 15, a second regulating and diverting tank 16, an organic phase circulation unit metering pump 17, an organic phase circulation unit electromagnetic flowmeter 18, a hydrogen peroxide metering pump 19, a hydrogen peroxide electromagnetic flowmeter 20, and a hydrogen peroxide storage tank 21.

[0075] The structure of the reactor is as follows: Figure 2 As shown, it includes an anode end plate 501, a first gasket 502, an anode current collector 503, a second gasket 504, an anode current guide plate 505, an integrated membrane electrode 4, a cathode current guide plate 507, a third gasket 508, a cathode current collector 509, a fourth gasket 510, and a cathode end plate 511 arranged in sequence.

[0076] The anode guide plate 505 and the integrated membrane electrode 4 form an anode cavity, which is provided with an anode inlet and an anode outlet; the cathode guide plate 507 and the integrated membrane electrode 4 form a cathode cavity, which is provided with a cathode inlet and a cathode outlet.

[0077] The cathode circulating liquid storage tank 6 is connected to the cathode inlet via the cathode metering pump 7 and the cathode electromagnetic flow meter 8, and the cathode outlet is connected to the mixing reaction tank 9 and the first regulating and diverting tank 10 in sequence. The first regulating and diverting tank 10 is connected to the cathode circulating liquid storage tank 6 via the aqueous phase circulation unit metering pump 11 and the aqueous phase circulation unit electromagnetic flow meter 12, and is also connected to the oxidation tank 15 via the oxidation tank metering pump 13 and the oxidation tank electromagnetic flow meter 14.

[0078] The anode storage tank 1 is connected to the anode inlet via the anode metering pump 2 and the anode electromagnetic flowmeter 3, and the anode outlet is connected to the oxidation tank 15 and the second regulating and diverting tank 16 in sequence. The second regulating and diverting tank 16 is connected to the mixing reaction tank via the organic phase circulation unit metering pump 17 and the organic phase circulation unit electromagnetic flowmeter 18, while the hydrogen peroxide metering pump 19 and the hydrogen peroxide electromagnetic flowmeter 20 are connected to the hydrogen peroxide storage tank.

[0079] In this invention, the mixing reaction tank is a cylindrical internal circulation reaction tank, which includes a top water inlet, a screw ribbon agitator, and a bottom water outlet.

[0080] In this invention, both the first regulating diversion pool and the second regulating diversion pool are right-angled trapezoids with an inclination angle of 30~90°, preferably 45~75°, more preferably 50~70°, and even more preferably 60°.

[0081] In this invention, the oxidation tank is a cylindrical oxidation reaction tank, which includes an inlet, a gas-liquid distribution plate, a stirrer, and an outlet. The gas-liquid distribution plate includes multiple staggered gas channels and liquid channels. The gas channels are equipped with microporous aeration discs, and the liquid channels are equipped with water distribution plates with a pore size of 0.1~0.5mm, so that the oxygen flowing into the oxidation tank is evenly distributed. The pore size of the water distribution plate is preferably 0.2~0.4mm, and more preferably 0.3mm.

[0082] This invention also provides an application of the above-mentioned apparatus for the directed reduction and oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide in the synthesis of hydrogen peroxide. The specific application method includes the following steps:

[0083] S1. Connect the positive and negative terminals of the reactor to a DC regulated power supply, add pure water to the anode storage tank, and add anthraquinone derivatives to the cathode circulating storage tank;

[0084] 1-Hexanol was added as a solvent and tetrabutylammonium chloride as an organic ligand to the mixing reaction tank;

[0085] The anthraquinone-derived compound is an anthraquinone-derived sodium salt solution;

[0086] S2. Pure water in the anode storage tank is introduced into the anode inlet of the reactor, while anthraquinone-derived sodium salt solution in the cathode circulation storage tank is introduced into the cathode inlet of the reactor.

[0087] S3. Start the DC regulated power supply to begin electrolysis. The oxygen and pure water generated at the anode enter the oxidation tank, and the hydrogenated anthraquinone-derived sodium salt solution generated at the cathode enters the mixed reaction tank.

[0088] S4. The sodium salt solution of hydrogenated anthraquinone derivative reacts in a mixed reaction tank to obtain a mixed reaction liquid containing hydrogenated anthraquinone derivative ammonium salt compounds. This mixed reaction liquid is then introduced into the first regulating and splitting tank. After separation in the first regulating and splitting tank, an aqueous phase containing anthraquinone derivative sodium salt and an organic phase containing hydrogenated anthraquinone derivative ammonium salt compounds are obtained. The aqueous phase is introduced into the cathode circulating storage tank, and the organic phase containing hydrogenated anthraquinone derivative ammonium salt compounds is introduced into the oxidation tank.

[0089] S5. In the oxidation tank, hydrogenated anthraquinone-derived ammonium salt compounds react with oxygen to obtain a mixed reaction liquid containing hydrogen peroxide, which is then introduced into the second regulating and diverting tank to obtain an aqueous phase containing hydrogen peroxide and an organic phase of anthraquinone-derived ammonium salt compounds regenerated after the reaction; wherein, the aqueous phase is introduced into the hydrogen peroxide storage tank, and the organic phase is introduced into the mixed reaction tank.

[0090] In this invention, the current density of the DC regulated power supply is 20~200 mA cm⁻¹. -2 Preferably 50~150 mAcm -2 More preferably 80~120 mA cm -2 More preferably 100 mA cm -2 .

[0091] In this invention, the anthraquinone-derived sodium salt includes one or more of sodium anthraquinone sulfonate, sodium anthraquinone-2-sulfonate, sodium anthraquinone-1,5-disulfonate, and sodium 1-aminoanthraquinone-2-sulfonate.

[0092] In this invention, the concentration of the anthraquinone-derived sodium salt solution in step S1 is 0.1~0.5 mol / L, preferably 0.2~0.4 mol / L, more preferably 0.25~0.35 mol / L, and even more preferably 0.3 mol / L.

[0093] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0094] Example 1

[0095] (1) Fabrication of integrated membrane electrode:

[0096] 150 mg of palladium on carbon nanoparticles, 7.5 mL of isopropanol, 2.5 mL of 10% perfluorosulfonic acid resin solution (Nafion D520) and 10 mL of pure water were mixed. The mixture was stirred for 30 min, sonicated at 5 °C for 1 h, ball-milled at 600 rpm at 3 °C for 30 min, and sheared at high speed at 15 °C for 40 min to obtain the cathode catalyst slurry.

[0097] 150 mg of iridium oxide nanoparticles, 5 mL of isopropanol, 5 mL of a 5% perfluorosulfonic acid resin solution (containing 0.22 g of perfluorosulfonic acid resin) and 5 mL of pure water were mixed. The mixture was stirred for 60 min, sonicated at 5 °C for 1 h, ball-milled at 600 rpm at 3 °C for 180 min, and sand-milled at 1500 rpm for 20 min to obtain the anode catalyst slurry.

[0098] A 120 μm thick perfluorosulfonic acid proton exchange membrane was selected. Cathode and anode catalyst slurries were sprayed onto both sides of the membrane. The slurry pressure was set to 0.45 bar, the atomization pressure to 4.5 bar, the spraying pressure to 0.8 bar, and the nozzle moving speed to 50 mm / min. After spraying, the membrane was dried at 60 °C for 24 h to obtain an integrated membrane electrode with loaded cathode and anode catalyst layers. The loading of the cathode catalyst on the proton exchange membrane was 1 mg / cm³. 2 The loading of the anode catalyst on the proton exchange membrane was 0.5 mg / cm³. 2 .

[0099] The electrochemical performance of the integrated membrane electrode prepared in step (1) was tested using the following method:

[0100] according to Figure 5 The apparatus shown is assembled into an electrochemical reaction device for the electrocatalytic reduction of sodium anthraquinone sulfonate in hydrogenated water. The power supply in the device is a DC power supply, and the membrane electrode area is 25 cm². 2 The anode chamber is circulated with pure water at a flow rate of 10 mL / min; the cathode chamber is circulated with 150 mL of 0.1 M sodium anthraquinone sulfonate solution at a circulation flow rate of 10 mL / min; the current density is 30 mA / cm². 2 On the anode side, the oxygen evolution reaction of pure water produces H protons that pass through the proton exchange membrane. These protons are reduced to active hydrogen at the cathode, hydrogenating sodium anthraquinone sulfonate to sodium hydrogen anthraquinone sulfonate, which is then discharged from the cathode chamber. The concentration of sodium hydrogen anthraquinone sulfonate produced under the above conditions is as follows: Figure 6 As shown, after 1 hour of reaction, the sodium hydrogen anthraquinone sulfonate concentration reached 90.14 ± 3.87 mmol / L, and the Faraday efficiency reached 96.64 ± 4.15%. The conversion rate of anthraquinone was as follows: Figure 7 As shown, the efficiency reaches 90.14% after 60 minutes. The above tests demonstrate that the integrated membrane electrode prepared in this embodiment exhibits excellent electrochemical performance, efficiently reducing and hydrogenating anthraquinones to hydrogenated anthraquinones using water as the hydrogen source without the need for hydrogen gas.

[0101] Assembly such as Figure 8The anthraquinone phase transfer apparatus shown includes an anthraquinone salt solution storage tank, a mixing reaction tank, a first regulating flow tank, and corresponding metering pumps and electromagnetic flowmeters. The mixing reaction tank contains 200 mL of 1-hexanol, and the tetrabutylammonium chloride concentrations are set to 0.2, 0.3, 0.4, 0.5, and 0.6 mol / L, respectively. The storage tank contains 150 mL of 0.1 mol / L sodium anthraquinone sulfonate aqueous solution and sodium anthraquinone sulfonate hydrogen salt solution, respectively, added to the mixing reaction tank at a flow rate of 10 mL / min. The organic phase solution in the first regulating flow tank is refluxed back to the mixing reaction tank at a flow rate of 10 mL / min, and the anthraquinone salt solution is refluxed back to the storage tank at a flow rate of 10 mL / min. Under the above conditions, the phase transfer coefficients corresponding to different tetrabutylammonium chloride concentrations were obtained by testing the concentrations of sodium anthraquinone sulfonate and sodium anthraquinone sulfonate hydrogen salt in the storage tank, as follows: Figure 9 As shown in the figure, the optimal tetrabutylammonium chloride concentration is 0.5 mL / min.

[0102] (2) Construct the integrated membrane electrode as shown in step 1. Figure 1 The apparatus shown is used for the directed reduction-oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide.

[0103] The mixing reaction tank is a cylindrical internal circulation reaction tank, which includes a top water inlet, a screw ribbon agitator, and a bottom water outlet.

[0104] Both the first and second regulating diversion tanks are right-angled trapezoids with an inclination angle of 45°.

[0105] The oxidation tank is a cylindrical oxidation reaction tank, which includes an inlet, a gas-liquid distribution plate, a stirrer and an outlet. The gas-liquid distribution plate is equipped with staggered gas channels and liquid channels. The gas channels are equipped with microporous aeration discs and the liquid channels are equipped with water distribution plates with a pore size of 0.1 mm.

[0106] (3) Preparation of hydrogen peroxide:

[0107] Pure water from the anode storage tank is used as the electrolyte and enters the pure water supply path. Under the action of the anode electromagnetic flowmeter and anode metering pump, it quantitatively enters the anode chamber of the reactor. Anthraquinone sulfonate aqueous solution from the cathode circulating storage tank is used as the electrolyte and enters the anthraquinone salt solution supply path. Under the action of the cathode electromagnetic flowmeter and cathode metering pump, it quantitatively enters the cathode chamber of the reactor. A constant current is applied by the DC regulated power supply, and the reactor simultaneously performs overcurrent electrolysis on both the cathode and anode electrolytes. Oxygen evolution occurs in the pure water on the anode side, and simultaneously... H protons pass through the proton exchange membrane and are reduced to active hydrogen at the cathode, reacting with sodium anthraquinone sulfonate to form sodium anthraquinone sulfonate hydrogen. The sodium anthraquinone sulfonate hydrogen salt solution produced at the cathode enters the mixing reaction tank, while oxygen and pure water produced at the anode enter the oxidation tank. In the mixing reaction tank, 1-hexanol serves as the organic solvent, and tetrabutylammonium chloride acts as the organic ligand. After the sodium anthraquinone sulfonate hydrogen salt solution enters through the top inlet, a screw-ribbon agitator is started to thoroughly mix it. The sodium anthraquinone sulfonate hydrogen salt in the aqueous phase solution is transferred to the organic phase solution through ion exchange to form ammonium anthraquinone sulfonate hydrogen. In the liquid, after the aqueous and organic phase solutions are mixed and reacted, they enter the first regulating and diverting tank, where they separate into an organic phase of anthraquinone sulfonate ammonium hydrogen solution and an aqueous phase of anthraquinone salt solution. When the solution in the first regulating and diverting tank reaches the set level, the metering pump, electromagnetic flowmeter of the aqueous phase circulation unit, metering pump of the oxidation tank, and electromagnetic flowmeter of the oxidation tank are activated. The aqueous phase solution is circulated through the aqueous phase circulation unit to the cathode circulating storage tank for reuse, while the anthraquinone sulfonate ammonium hydrogen solution enters the oxidation tank through the metering pump and electromagnetic flowmeter of the oxidation tank. The stirring of the oxidation tank is then activated. In the electrochemical device, oxygen generated at the anode and pure water simultaneously enter the oxidation tank through the bottom gas-liquid distribution plate to react with ammonium hydrogen anthraquinone sulfonate to produce H2O2. The fully reacted and mixed solution enters the second regulating and diverting tank, where H2O2 is transferred to the aqueous phase solution. The bottom effluent is pure H2O2, which is then fed into the hydrogen peroxide storage tank via a hydrogen peroxide metering pump and an electromagnetic flowmeter. The anthraquinone organic solution, ammonium anthraquinone sulfonate, regenerated at the top is circulated to the mixing reaction tank via an organic phase circulation unit metering pump and an electromagnetic flowmeter.

[0108] The specific experimental parameters are as follows: the area of ​​the integrated membrane electrode is 25 cm². 2 A 0.3M sodium anthraquinone sulfonate aqueous solution is introduced into the cathode chamber at a flow rate of 10 mL / min; the current density is 100 mA / cm². 2 1-Hexanol and tetrabutylammonium chloride are added to the mixing reaction tank. The volume of 1-hexanol is 200 mL, and the concentration of tetrabutylammonium chloride is 0.5 M. The organic phase solution after stratification in the first regulating and diverting tank enters the oxidation tank at a flow rate of 4 mL / min. Pure water is circulated in the anode chamber at a flow rate of 2 mL / min. Anthraquinone material in the second regulating and diverting tank is recycled to the mixing reaction tank through the organic phase circulation system at a flow rate of 4 mL / min. H2O2 flows out at a flow rate of 2 mL / min. The H2O2 concentration is as follows: Figure 10As shown, it can stably reach a concentration of over 1 wt%. A full-spectrum absorbance scan of the H2O2 aqueous solution yielded the following results: Figure 11 As shown, this indicates that there are no anthraquinone organic compounds in the aqueous solution of H2O2.

[0109] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An apparatus for the directed reduction-oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide, characterized in that, The apparatus for the directed reduction-oxidation regulation synthesis of hydrogen peroxide from anthraquinone-derived compounds includes an anode storage tank, a reactor, a cathode circulating storage tank, a mixing reaction tank, a first regulating and diverting tank, an oxidation tank, a second regulating and diverting tank, and a hydrogen peroxide storage tank. The reactor stack includes an anode end plate, a first gasket, an anode current collector, a second gasket, an anode current guide plate, an integrated membrane electrode, a cathode current guide plate, a third gasket, a cathode current collector, a fourth gasket, and a cathode end plate, which are stacked sequentially. The anode guide plate and the integrated membrane electrode form an anode cavity, which is provided with an anode inlet and an anode outlet; the cathode guide plate and the integrated membrane electrode form a cathode cavity, which is provided with a cathode inlet and a cathode outlet. The cathode circulating liquid storage tank is connected to the cathode inlet, and the cathode outlet is sequentially connected to the mixing reaction tank and the first regulating and diverting tank; the first regulating and diverting tank is connected to the cathode circulating liquid storage tank and the oxidation tank respectively. The anode storage tank is connected to the anode inlet, and the anode outlet is sequentially connected to the oxidation tank and the second regulating and diverting tank; the second regulating and diverting tank is connected to the mixing reaction tank and the hydrogen peroxide storage tank respectively. The method for preparing the integrated membrane electrode includes the following steps: 1) The cathode catalyst, the first perfluorosulfonic acid resin solution, and the first mixed solvent are mixed to obtain a cathode catalyst slurry; 2) The anode catalyst, the second perfluorosulfonic acid resin solution, and the second mixed solvent are mixed to obtain the anode catalyst slurry; 3) The cathode catalyst slurry and the anode catalyst slurry are sprayed onto both sides of the proton exchange membrane to obtain an integrated membrane electrode with a cathode catalyst layer and an anode catalyst layer loaded. Steps 1 and 2) are not in any particular order; The cathode catalyst mentioned in step 1) is palladium nanoparticles and / or palladium carbon nanoparticles; The anode catalyst mentioned in step 2) is nano-iridium oxide particles; The integrated membrane electrode is used for the directed reduction and oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide. The anthraquinone-derived compound is an anthraquinone-derived sodium salt solution; the anthraquinone-derived sodium salt includes one or more of sodium anthraquinone sulfonate, sodium anthraquinone-2-sulfonate, and sodium anthraquinone-1,5-disulfonate.

2. The apparatus for the directed reduction-oxidation synthesis of hydrogen peroxide from anthraquinone-derived compounds according to claim 1, characterized in that, In step 1), the mass fraction of the first perfluorosulfonic acid resin solution is 3-20%. The mass ratio of the cathode catalyst to the perfluorosulfonic acid resin in the first perfluorosulfonic acid resin solution is 1:1~5.

3. The apparatus for the directed reduction-oxidation synthesis of hydrogen peroxide from anthraquinone-derived compounds according to claim 2, characterized in that, In step 2), the mass fraction of the second perfluorosulfonic acid resin solution is 3-20%. The mass ratio of the anode catalyst to the perfluorosulfonic acid resin in the second perfluorosulfonic acid resin solution is 1:1~2.

4. An apparatus for the directed reduction-oxidation synthesis of hydrogen peroxide from anthraquinone-derived compounds according to any one of claims 1 to 3, characterized in that, The proton exchange membrane mentioned in step 3) is a perfluorosulfonic acid proton exchange membrane with a thickness of 50~200μm; The cathode catalyst is loaded onto the proton exchange membrane at a rate of 0.5~5 mg / cm³. -2 ; The loading of the anode catalyst on the proton exchange membrane is 0.5~5 mg cm⁻¹. -2 .

5. The apparatus for the directed reduction-oxidation synthesis of hydrogen peroxide from anthraquinone-derived compounds according to claim 4, characterized in that, The mixing reaction tank is a cylindrical internal circulation reaction tank, which includes a top water inlet, a screw ribbon agitator and a bottom water outlet. Both the first regulating diversion tank and the second regulating diversion tank are right trapezoids with an inclination angle of 30~90°.

6. The apparatus for the directed reduction-oxidation synthesis of hydrogen peroxide from anthraquinone-derived compounds according to claim 5, characterized in that, The oxidation tank is a cylindrical oxidation reaction tank, which includes an inlet, a gas-liquid distribution plate, a stirrer and an outlet. The gas-liquid distribution plate includes multiple staggered gas channels and liquid channels. The gas channels are equipped with microporous aeration discs and the liquid channels are equipped with water distribution plates with a pore size of 0.1~0.5mm, so that the oxygen flowing into the oxidation tank is evenly distributed.

7. The application of the apparatus according to any one of claims 1 to 6 for the directed reduction-oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide in the synthesis of hydrogen peroxide, characterized in that, Includes the following steps: S1. Connect the positive and negative terminals of the reactor to a DC regulated power supply, add pure water to the anode storage tank, and add anthraquinone derivatives to the cathode circulating storage tank; 1-Hexanol was added as a solvent and tetrabutylammonium chloride as an organic ligand to the mixing reaction tank; The anthraquinone-derived compound is an anthraquinone-derived sodium salt solution; S2. Pure water in the anode storage tank is introduced into the anode inlet of the reactor, while anthraquinone-derived sodium salt solution in the cathode circulation storage tank is introduced into the cathode inlet of the reactor. S3. Start the DC regulated power supply to begin electrolysis. The oxygen and pure water generated at the anode enter the oxidation tank, and the hydrogenated anthraquinone-derived sodium salt solution generated at the cathode enters the mixed reaction tank. S4. The sodium salt solution of hydrogenated anthraquinone derivative reacts in a mixed reaction tank to obtain a mixed reaction liquid containing hydrogenated anthraquinone derivative ammonium salt compounds. This mixed reaction liquid is then introduced into the first regulating and splitting tank. After separation in the first regulating and splitting tank, an aqueous phase containing anthraquinone derivative sodium salt and an organic phase containing hydrogenated anthraquinone derivative ammonium salt compounds are obtained. The aqueous phase is introduced into the cathode circulating storage tank, and the organic phase containing hydrogenated anthraquinone derivative ammonium salt compounds is introduced into the oxidation tank. S5. In the oxidation tank, hydrogenated anthraquinone-derived ammonium salt compounds react with oxygen to obtain a mixed reaction liquid containing hydrogen peroxide, which is then introduced into the second regulating and diverting tank to obtain an aqueous phase containing hydrogen peroxide and an organic phase of anthraquinone-derived ammonium salt compounds regenerated after the reaction; wherein, the aqueous phase is introduced into the hydrogen peroxide storage tank, and the organic phase is introduced into the mixed reaction tank.

8. The application of the apparatus for the directed reduction-oxidation regulation of anthraquinone-derived compounds to synthesize hydrogen peroxide according to claim 7 in the synthesis of hydrogen peroxide, characterized in that, The current density of the DC regulated power supply is 20~200 mAcm. -2 ; The concentration of the anthraquinone-derived sodium salt solution in step S1 is 0.1~0.5 mol / L.

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