Hydrogen production device coupled with water electrolysis cathode for preparing p-benzoquinone by electrocatalytic oxidation of hydroquinone and application thereof

Abstract

The application provides a device and application for preparing p-benzoquinone by electrocatalytic oxidation of hydroquinone and coupling water electrolysis cathode hydrogen production, wherein the mixed electrolytic water system comprises electrolyte, diaphragm and membrane electrode, and the polar plate with flow channel. The application uses hydroquinone oxidation instead of anode oxygen evolution reaction (OER) of electrolytic water, which can significantly reduce the voltage of the system. The electrocatalytic oxidation of hydroquinone to generate p-benzoquinone can be carried out at 0.7 V (vs. RHE), which is 1.8 V lower than OER, and the system power consumption is reduced by nearly two-thirds. The application successfully reduces the system voltage of the hydrogen production system by electrocatalytic oxidation of hydroquinone coupled with electrolytic water by selecting or synthesizing catalysts, selecting a suitable ion exchange membrane, controlling the system voltage, etc., and the product is single and has higher economic value, and can be separated by simple filtration.

Description

Technical Field

[0001] This invention relates to the fields of membrane electrode preparation and electrocatalysis, and particularly to a device for producing hydrogen from hydroquinone by electrocatalytic oxidation of hydroquinone coupled with water electrolysis cathode and its application. Background Technology

[0002] A stable and secure energy supply is fundamental to the survival and development of human society. However, with rapid socio-economic development and continuous population growth, the energy shortage problem is becoming increasingly serious, and the overuse of fossil fuels has brought many environmental problems to human society. Currently, fossil fuels still account for the largest share of global energy consumption. Therefore, finding a renewable and clean energy source to replace fossil fuels has become extremely urgent. Hydrogen is a clean, green, and high-energy-density sustainable energy carrier, and is considered the most promising alternative to fossil fuels. However, current industrial hydrogen production still mainly relies on the reforming of fossil fuels such as natural gas, oil, and coal. The high-temperature and high-pressure reaction conditions require the consumption of fossil fuels, which increases the emission of carbon dioxide greenhouse gases.

[0003] Electrolysis of water, utilizing renewable energy sources such as solar and wind power, is a green, sustainable, and environmentally friendly method for producing hydrogen. The hydrogen production process mainly consists of two half-reactions: the oxygen evolution reaction (OER) at the anode and the hydrogen evolution reaction (HER) at the cathode. Ideally, hydrogen production via water electrolysis requires a thermodynamic voltage of 1.23V. However, in practical applications, both half-reactions exhibit overpotentials during electrolysis, especially the anode OER, which is a complex and kinetically slow four-electron transfer process requiring high activation energy. Therefore, higher cell voltages are needed to maintain a high hydrogen production rate. Furthermore, the oxygen (O2) produced at the anode is a low-value product, and its mixing with the hydrogen (H2) produced at the cathode poses a potential safety risk of explosion. Therefore, developing an efficient, stable, economical, and safe water electrolysis hydrogen production system is of paramount importance. Summary of the Invention

[0004] To address the problems of high system voltage, low current density, and high energy consumption in current water electrolysis hydrogen production systems, this invention uses the electro-oxidation reaction of hydroquinone instead of the anodic oxygen evolution reaction (OER), which can significantly reduce the system voltage. The electrochemical oxidation of hydroquinone to p-benzoquinone can be carried out at 0.7V (vs. SHE), compared to 1.8V for OER, reducing system energy consumption by nearly two-thirds. This invention successfully reduces the system voltage of hydroquinone electrocatalytic oxidation coupled with water electrolysis for hydrogen production by using a high-performance catalyst, selecting a suitable ion exchange membrane, and controlling the system voltage. The anodic product is p-benzoquinone, and the cathode product is high-purity hydrogen.

[0005] This invention significantly improves system performance and reduces energy consumption by selecting a high-performance electrocatalyst and improving the design of the electrolytic cell, thereby obtaining a single product, p-benzoquinone.

[0006] This application reduces the system voltage for hydrogen production by coupling hydroquinone electrocatalytic oxidation with water electrolysis, while keeping the conditions for hydrogen production at the cathode unchanged, by using hydroquinone oxidation instead of OER at the anode.

[0007] To achieve the above objectives, the first aspect of this application provides a hydroquinone electrocatalytic oxidation device coupled with a water electrolysis cathode for hydrogen production. The mixed water electrolysis device includes a membrane electrode placed between two plates. The membrane electrode includes a cathode catalyst layer, a diaphragm, and an anode catalyst layer stacked together. The two plates are respectively attached to the surfaces on both sides of the membrane electrode.

[0008] The two plates have a flow field on the side facing the membrane electrode for the electrolyte to flow through. The cathode electrolyte is introduced into the flow field through the inlet of the flow field on the plate near the cathode catalyst layer on the membrane electrode, flows through the flow field and the cathode catalyst layer, and then flows out through the outlet of the flow field. The anolyte is introduced into the flow field through the inlet of the flow field on the plate near the anolyte catalyst layer on the membrane electrode, flows through the flow field and the anolyte catalyst layer, and then flows out through the outlet of the flow field.

[0009] The anolyte is an inorganic acid solution containing the organic substrate hydroquinone, and the catholyte is an inorganic acid solution.

[0010] Furthermore, the inorganic acid in the anolyte is an aqueous solution of one or two of sulfuric acid and perchloric acid; the concentration of the inorganic acid is 0.1 mol / L to 2 mol / L.

[0011] Preferably, the inorganic acid is sulfuric acid, and the concentration of sulfuric acid is 0.2 mol / L to 1 mol / L.

[0012] Furthermore, the concentration of the substrate hydroquinone was 0.04 mol / L to 0.3 mol / L;

[0013] Preferably, the hydroquinone concentration is 0.2 mol / L to 0.3 mol / L.

[0014] Furthermore, the cathode electrolyte is an aqueous solution of one or two of sulfuric acid or perchloric acid, with a concentration of 0.1 mol / L to 2 mol / L;

[0015] Preferably, the cathode electrolyte is sulfuric acid with a concentration of 0.2 mol / L to 1 mol / L.

[0016] Furthermore, the anode catalyst layer includes an anode catalyst and an ionomer; the anode catalyst is one or more of manganese dioxide, iridium oxide, platinum ruthenium carbon, and platinum carbon; the ionomer is Nafion; the mass ratio of the anode catalyst to the ionomer is 20:1 to 5:1;

[0017] Preferably, the anode catalyst is platinum-ruthenium carbon, and the mass ratio of platinum-ruthenium carbon to ionomer is 12:1 to 8:1.

[0019] Furthermore, the cathode catalyst layer includes a cathode catalyst and an ionomer; the cathode catalyst is one or more of platinum-ruthenium carbon and platinum-carbon; the ionomer is Nafion; the mass ratio of the cathode catalyst to the ionomer is 20:1 to 5:1;

[0020] Preferably, the cathode catalyst is platinum-ruthenium carbon, and the mass ratio of platinum-ruthenium carbon to ionomer is 12:1 to 8:1.

[0022] Furthermore, the diaphragm is a proton exchange membrane with proton conduction, including the Nafion membrane.

[0023] Further, the preparation method of the membrane electrode is as follows: a slurry containing an anode catalyst and Nafion or a slurry containing a cathode catalyst and Nafion is coated onto a support to obtain an anode catalyst layer and a cathode catalyst layer. Then, the catalyst-coated side of the anode catalyst layer and the cathode catalyst layer are respectively or simultaneously stacked with the membrane to obtain the membrane electrode.

[0024] Preferably, the carrier is selected from one or more of the following: nickel foam mesh, carbon paper, carbon felt, titanium felt, and titanium mesh.

[0025] Furthermore, the device is composed of a cathode plate with a serpentine flow field, an annular fluororubber sheet, a membrane electrode, an annular fluororubber sheet, and an anode plate with a serpentine flow field stacked sequentially to form a zero-gap water electrolysis cell; an electric heating element and a thermocouple are respectively provided in the two electrode plates.

[0026] The electric heating element is a heating wire or heating rod. The thermocouple is connected to an external temperature controller via a wire. The electric heating element is connected to an external power source via a wire through the external temperature controller.

[0027] The device further includes a cathode electrolyte storage tank containing cathode electrolyte, wherein the cathode electrolyte is connected to the inlet of the flow field of the cathode plate via a pump and a pipeline, and the outlet of the flow field of the cathode plate is connected to the cathode electrolyte storage tank via a pipeline; the device further includes an anolyte storage tank containing anolyte, wherein the anolyte is connected to the inlet of the flow field of the anode plate via a pump and a pipeline, and the outlet of the flow field of the anode plate is connected to the anolyte storage tank via a pipeline.

[0028] The second aspect of this application provides an apparatus for the combined production process of p-benzoquinone and hydrogen, with an operating temperature of 30–90°C.

[0029] This invention uses hydroquinone oxidation instead of the anodic oxygen evolution reaction (OER) in water electrolysis, which significantly reduces the system voltage. The electrocatalytic oxidation of hydroquinone to p-benzoquinone can be carried out at 0.7V (vs. RHE), compared to 1.8V for OER, reducing system energy consumption by nearly two-thirds. This invention successfully reduces the system voltage of hydroquinone electrocatalytic oxidation coupled with water electrolysis for hydrogen production by selecting or synthesizing catalysts, choosing suitable ion exchange membranes, and controlling system voltage. The product obtained is a single, more economically valuable p-benzoquinone, which can be separated simply by filtration.

[0030] The beneficial effects that this application can produce include:

[0031] (1) The electrochemical method provided in this application prepares p-benzoquinone from hydroquinone with high product selectivity. The oxidation product p-benzoquinone can be separated by simple filtration. At the same time, it reduces the energy consumption of the system, requiring only 1.0V or even lower system voltage. Furthermore, hydrogen can be obtained at the cathode simultaneously.

[0032] (2) By selecting or synthesizing catalysts, selecting suitable ion exchange membranes, and controlling system voltage, this application has successfully reduced the system voltage of hydroquinone electrocatalytic oxidation coupled with water electrolysis to produce hydrogen. The product obtained is a single, more economical p-benzoquinone, which can be separated by a simple filtration operation. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the mixed water electrolysis system for the electrocatalytic oxidation of hydroquinone to p-benzoquinone coupled with a cathode for hydrogen production, as described in this application.

[0034] Figure 2The polarization curves (LSV) of the PtRu / C (Sinero) catalyst in the rotating disk three-electrode system of this application in 0.5 M H2SO4 + 0.04 M hydroquinone solution and 0.5 M H2SO4 are compared.

[0035] Figure 3 The image shows the constant current test curve (Vt) of the PtRu / C (Sinero) catalyst in a rotating disk three-electrode system in a 0.5 M H₂SO₄ + 0.04 M hydroquinone solution, with a current density of 20 mA / cm². 2 . Figure 4 The polarization curves (LSV) are shown in Example 1 of this application, where the anode uses a 1M H2SO4 + 0.25M hydroquinone solution as the PtRu / C(Sinero) catalyst and the cathode uses a 1M H2SO4 catalyst.

[0036] Figure 5 The constant voltage test curve (it) is shown in Example 1 of this application, in which the PtRu / C(Sinero) catalyst is 1M H2SO4 + 0.25M hydroquinone solution and the PtRu / C(Sinero) catalyst is 1M H2SO4 at the cathode, with a cell voltage of 1.0V.

[0037] Figure 6 The anode product obtained using the PtRu / C (Sinero) catalyst in Example 1 of this application and the filter residue obtained by simple filtration are shown.

[0038] Figure 7 The NMR spectra of the 1H NMR and 1C NMR spectra of the anode filter residue obtained using the PtRu / C (Sinero) catalyst in Example 1 of this application are shown.

[0039] Figure 8 The polarization curves (LSV) of the anodic hydroquinone oxidation coupled to the cathode for hydrogen production in acidic (Example 1) and neutral (Comparative Example 2) environments are compared.

[0040] Figure 9 This is a schematic diagram of the electrolytic cell structure used in this application; wherein, 1: cathode plate; 2: cathode gasket; 3: membrane electrode; 31: cathode catalyst layer; 32: diaphragm; 33: anode catalyst layer; 4: anode gasket; 5: anode plate. Detailed Implementation

[0041] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0042] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0043] The transmission electron microscope used in this application is a JEM-2100 from Nippon Electron Ltd.; the liquid nuclear magnetic resonance spectrometer is a Bruker AVANCE III HD 400MHz from Germany; and the electrochemical workstation is a Bio-Logic SP-50e / 150e from France.

[0044] In the following embodiments of the present invention, a hybrid water electrolysis system for the electrocatalytic oxidation of hydroquinone to produce p-benzoquinone coupled with cathode hydrogen production includes the following steps:

[0045] (1) The zero-gap structure single cell consists of a cathode plate and an anode plate with a serpentine flow field, an annular fluororubber gasket, and a membrane electrode. Heating elements and thermocouples are installed inside the cathode and anode plates to control the temperature of the electrolytic cell; (see...) Figure 9 )

[0046] The device is composed of a cathode plate 1 with a serpentine flow field, an annular fluororubber cathode gasket 2, a membrane electrode 3, an annular fluororubber anode gasket 4, and an anode plate 5 with a serpentine flow field stacked in sequence to form a zero-gap water electrolysis cell; an electric heating element and a thermocouple are respectively provided in the anode plate 1 and the cathode plate 5.

[0047] The electric heating element is an electric heating rod. The thermocouple is connected to an external temperature controller via wires. The electric heating element is connected to an external power source via wires through the external temperature controller.

[0048] The device further includes a cathode electrolyte storage tank containing cathode electrolyte, wherein the cathode electrolyte is connected to the inlet of the flow field of the cathode plate via a pump and a pipeline, and the outlet of the flow field of the cathode plate is connected to the cathode electrolyte storage tank via a pipeline; the device further includes an anolyte storage tank containing anolyte, wherein the anolyte is connected to the inlet of the flow field of the anode plate via a pump and a pipeline, and the outlet of the flow field of the anode plate is connected to the anolyte storage tank via a pipeline.

[0049] (2) The membrane electrode 3 of the water electrolysis device is composed of a cathode catalyst layer 31, a membrane 32, and an anode catalyst layer 33 stacked sequentially. The cathode catalyst layer 31 is made by coating a slurry containing a cathode catalyst and Nafion onto one side of the carrier surface, and the anode catalyst layer 33 is made by coating a slurry containing an anode catalyst and Nafion onto one side of the carrier surface. The membrane electrode is prepared by coating a slurry containing either an anode or cathode catalyst and Nafion onto the carrier to obtain an anode catalyst layer and a cathode catalyst layer, respectively. Then, the catalyst-coated sides of the anode catalyst layer and the cathode catalyst layer are stacked with the membrane, either separately or simultaneously, to obtain the membrane electrode.

[0050] (3) The area of ​​the catalyst layer is 2x2=4cm2 The device was used to evaluate the electrolytic performance of the coupling system.

[0051] The mixed water electrolysis device includes a membrane electrode placed between two plates; the membrane electrode includes a cathode catalyst layer, a diaphragm, and an anode catalyst layer stacked together, and the two plates are respectively attached to one side surface of the membrane electrode;

[0052] Both the cathode plate and the anode plate have a flow field on the side facing the membrane electrode for the electrolyte to flow through. The cathode electrolyte is introduced into the flow field through the inlet of the flow field on the plate near the cathode catalyst layer on the membrane electrode, flows through the flow field and the cathode catalyst layer, and then flows out through the outlet of the flow field. The anode electrolyte is introduced into the flow field through the inlet of the flow field on the plate near the anode catalyst layer on the membrane electrode, flows through the flow field and the anode catalyst layer, and then flows out through the outlet of the flow field.

[0053] The anolyte is an inorganic acid solution containing the organic substrate hydroquinone, and the catholyte is an inorganic acid solution.

[0054] Figure 2 The polarization curves (LSV) of the PtRu / C (Sinero) catalyst in the rotating disk three-electrode system of this application in 0.5M H2SO4 + 0.04M hydroquinone solution and 0.5M H2SO4 are compared. The working electrode is a glassy carbon electrode, the reference electrode is a mercurous mercuric sulfate electrode, and the counter electrode is a graphite rod. The figure shows that the onset potential of hydroquinone oxidation is below 0.7V, much lower than the OER, indicating that introducing hydroquinone into the anolyte can significantly reduce the system voltage and decrease overall energy consumption.

[0055] Figure 3 The image shows the constant current test curve (Vt) of the PtRu / C (Sinero) catalyst in a rotating disk three-electrode system in a 0.5 M H₂SO₄ + 0.04 M hydroquinone solution, with a current density of 20 mA / cm². 2 As can be seen from the figure, hydroquinone oxidation can proceed stably at high current densities in the three-electrode system.

[0056] Example 1

[0057] A PtRu / C (Sinero) catalyst was mixed with a 5 wt% Nafion solution, isopropanol, and deionized water. The PtRu / C (Sinero) catalyst consisted of 40 wt% Pt and 20 wt% Ru. The mixture was then ultrasonically dispersed. The catalyst concentration in the mixture was 3 wt%, the Nafion concentration was 0.3 wt%, and the isopropanol concentration was 5 wt%. This mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2Using the same method as the anode, a slurry of PtRu / C (Sinero) catalyst ultrasonically dispersed with Nafion solution, isopropanol, and deionized water was uniformly coated onto carbon paper. After drying, the cathode catalyst layer was obtained, with a catalyst loading of 3 mg / cm³. 2 The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0058] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, thermocouple), and temperature control device were assembled into a single cell for testing. A 1M H₂SO₄ + 0.25M hydroquinone aqueous solution was introduced into the anode, and a 1M H₂SO₄ aqueous solution was introduced into the cathode. The electrolytic cell temperature was maintained at 80 degrees Celsius, and the electrolyte flow rate at both the anode and cathode was 3 ml / min.

[0059] Figure 4 The polarization curve (LSV) measured in this embodiment shows that in the full cell test, the current begins to increase rapidly when the cell voltage is less than 0.7V, which is consistent with the conclusion of the rotating disk three-electrode test.

[0060] Figure 5 The constant current test curve of this embodiment at a cell voltage of 1V shows that the full cell test can operate stably and with slow decay under low voltage and high current density.

[0061] The anode product obtained in this embodiment can be obtained through simple filtration. See Figure 6 ;

[0062] After washing and drying the filter residue, we conducted 1H NMR and 1C NMR tests. Figure 7 It can be seen that the product contains only p-benzoquinone and the organic substrate hydroquinone, and no other byproducts were found.

[0063] Example 2

[0064] Iridium oxide catalyst was mixed with 5 wt% Nafion solution, isopropanol, and deionized water, and then ultrasonically dispersed. The concentrations of the catalyst in the mixture were 3 wt%, Nafion 0.3 wt%, and isopropanol 5 wt%. The mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2 Using the same method as in Example 1, a slurry of PtRu / C (Sinero) catalyst, Nafion solution, isopropanol, and deionized water was ultrasonically dispersed, uniformly coated onto carbon paper, and dried to obtain a cathode catalyst layer with a catalyst loading of 3 mg / cm³. 2 The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0065] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, thermocouple), and temperature control device were assembled into a single cell for testing. A 1M H₂SO₄ + 0.25M hydroquinone aqueous solution was introduced into the anode, and a 1M H₂SO₄ aqueous solution was introduced into the cathode. The electrolytic cell temperature was maintained at 80 degrees Celsius, and the electrolyte flow rate at both the anode and cathode was 3 ml / min.

[0066] Example 3

[0067] MnO2 catalyst was mixed with 5 wt% Nafion solution, isopropanol, and deionized water, and then ultrasonically dispersed. In the mixture, the catalyst concentration was 3 wt%, the Nafion concentration was 0.3 wt%, and the isopropanol concentration was 5 wt%. This mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2 Using the same method as in Example 1, a slurry of PtRu / C (Sinero) catalyst, Nafion solution, isopropanol, and deionized water was ultrasonically dispersed, uniformly coated onto carbon paper, and dried to obtain a cathode catalyst layer with a catalyst loading of 3 mg / cm³. 2 The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0068] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, thermocouple), and temperature control device were assembled into a single cell for testing. A 1M H₂SO₄ + 0.25M hydroquinone aqueous solution was introduced into the anode, and a 1M H₂SO₄ aqueous solution was introduced into the cathode. The electrolytic cell temperature was maintained at 80 degrees Celsius, and the electrolyte flow rate at both the anode and cathode was 3 ml / min.

[0069] Example 4

[0070] A PtRu / C (Sinero) catalyst was mixed with a 5 wt% Nafion solution, isopropanol, and deionized water. The PtRu / C (Sinero) catalyst consisted of 40 wt% Pt and 20 wt% Ru. The mixture was then ultrasonically dispersed. The catalyst concentration in the mixture was 3 wt%, the Nafion concentration was 0.3 wt%, and the isopropanol concentration was 5 wt%. This mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2 Using the same method as the anode, a slurry of PtRu / C (Sinero) catalyst ultrasonically dispersed with Nafion solution, isopropanol, and deionized water was uniformly coated onto carbon paper. After drying, the cathode catalyst layer was obtained, with a catalyst loading of 3 mg / cm³. 2The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0071] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, thermocouple), and temperature control device were assembled into a single cell for testing. A 1M perchloric acid + 0.25M hydroquinone aqueous solution was introduced into the anode, and a 1M perchloric acid aqueous solution was introduced into the cathode. The electrolytic cell temperature was maintained at 80 degrees Celsius, and the electrolyte flow rate at both the anode and cathode was 3 ml / min.

[0072] Example 5

[0073] A PtRu / C (Sinero) catalyst was mixed with a 5 wt% Nafion solution, isopropanol, and deionized water. The PtRu / C (Sinero) catalyst consisted of 40 wt% Pt and 20 wt% Ru. The mixture was then ultrasonically dispersed. The catalyst concentration in the mixture was 3 wt%, the Nafion concentration was 0.3 wt%, and the isopropanol concentration was 5 wt%. This mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2 Using the same method as the anode, a slurry of PtRu / C (Sinero) catalyst ultrasonically dispersed with Nafion solution, isopropanol, and deionized water was uniformly coated onto carbon paper. After drying, the cathode catalyst layer was obtained, with a catalyst loading of 3 mg / cm³. 2 The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0074] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, thermocouple), and temperature control device were assembled into a single cell for testing. A 1M H₂SO₄ + 0.04M hydroquinone aqueous solution was introduced into the anode, and a 1M H₂SO₄ aqueous solution was introduced into the cathode. The electrolytic cell temperature was maintained at 80 degrees Celsius, and the electrolyte flow rate at both the anode and cathode was 3 ml / min.

[0075] Example 6

[0076] A PtRu / C (Sinero) catalyst was mixed with a 5 wt% Nafion solution, isopropanol, and deionized water. The PtRu / C (Sinero) catalyst consisted of 40 wt% Pt and 20 wt% Ru. The mixture was then ultrasonically dispersed. The catalyst concentration in the mixture was 3 wt%, the Nafion concentration was 0.3 wt%, and the isopropanol concentration was 5 wt%. This mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2Using the same method as the anode, a slurry of PtRu / C (Sinero) catalyst ultrasonically dispersed with Nafion solution, isopropanol, and deionized water was uniformly coated onto carbon paper. After drying, the cathode catalyst layer was obtained, with a catalyst loading of 3 mg / cm³. 2 The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0077] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, thermocouple), and temperature control device were assembled into a single cell for testing. A 1M H₂SO₄ + 0.25M hydroquinone aqueous solution was introduced into the anode, and a 1M H₂SO₄ aqueous solution was introduced into the cathode. The electrolytic cell temperature was maintained at 40 degrees Celsius, and the electrolyte flow rate at both the anode and cathode was 3 ml / min.

[0078] Comparative Example 1

[0079] A PtRu / C (Sinero) catalyst was mixed with a 5 wt% Nafion solution, isopropanol, and deionized water. The PtRu / C (Sinero) catalyst consisted of 40 wt% Pt and 20 wt% Ru. The mixture was then ultrasonically dispersed. The catalyst concentration in the mixture was 3 wt%, the Nafion concentration was 0.3 wt%, and the isopropanol concentration was 5 wt%. This mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2 Using the same method as the anode, a slurry of PtRu / C (Sinero) catalyst ultrasonically dispersed with Nafion solution, isopropanol, and deionized water was uniformly coated onto carbon paper. After drying, the cathode catalyst layer was obtained, with a catalyst loading of 3 mg / cm³. 2 The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0080] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, thermocouple), and temperature control device were assembled into a single cell for testing. A 1M H₂SO₄ + 0.25M methanol aqueous solution was introduced into the anode, and a 1M H₂SO₄ aqueous solution was introduced into the cathode. The electrolytic cell temperature was maintained at 80 degrees Celsius, and the electrolyte flow rate at both the anode and cathode was 3 ml / min.

[0081] Comparative Example 2

[0082] A PtRu / C (Sinero) catalyst was mixed with a 5 wt% Nafion solution, isopropanol, and deionized water. The PtRu / C (Sinero) catalyst consisted of 40 wt% Pt and 20 wt% Ru. The mixture was then ultrasonically dispersed. The catalyst concentration in the mixture was 3 wt%, the Nafion concentration was 0.3 wt%, and the isopropanol concentration was 5 wt%. This mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2 Using the same method as the anode, a slurry of PtRu / C (Sinero) catalyst ultrasonically dispersed with Nafion solution, isopropanol, and deionized water was uniformly coated onto carbon paper. After drying, the cathode catalyst layer was obtained, with a catalyst loading of 3 mg / cm³. 2 The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0083] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, thermocouple), and temperature control device were assembled into a single cell for testing. A 0.25M hydroquinone aqueous solution was introduced into the anode end, and pure water was introduced into the cathode end. The electrolytic cell temperature was maintained at 80 degrees Celsius, and the electrolyte flow rate at both the anode and cathode was 3 ml / min.

[0084] Figure 8 The polarization curves (LSV) for anodic hydroquinone oxidation coupled to cathodic hydrogen production are compared under acidic (Example 1) and neutral (Comparative Example 2) conditions. At the same current density, the lower the cell voltage in the acidic system, the lower the overall energy consumption.

[0085] Comparative Example 3

[0086] A PtRu / C (Sinero) catalyst was mixed with a 5 wt% Nafion solution, isopropanol, and deionized water. The PtRu / C (Sinero) catalyst consisted of 40 wt% Pt and 20 wt% Ru. The mixture was then ultrasonically dispersed. The catalyst concentration in the mixture was 3 wt%, the Nafion concentration was 0.3 wt%, and the isopropanol concentration was 5 wt%. This mixture was then uniformly coated onto a nickel foam support and dried to obtain the anode catalyst layer with a catalyst loading of 3 mg / cm³. 2 Using the same method as the anode, a slurry of PtRu / C (Sinero) catalyst ultrasonically dispersed with Nafion solution, isopropanol, and deionized water was uniformly coated onto carbon paper. After drying, the cathode catalyst layer was obtained, with a catalyst loading of 3 mg / cm³. 2 The anode catalyst layer and cathode catalyst layer are respectively attached to both sides of the Nafion membrane and then pressed together to form a membrane electrode assembly.

[0087] The obtained membrane electrode, annular fluororubber gasket, electrode clamps (including cathode plate, anode plate, heating rod, and thermocouple), and temperature control device were assembled into a single cell for testing. A 1M H₂SO₄ + 0.25M hydroquinone aqueous solution was introduced into the anode, and a 1M H₂SO₄ aqueous solution was introduced into the cathode. The electrolytic cell temperature was maintained at room temperature (25°C), and the electrolyte flow rate at both the anode and cathode was 3 ml / min. Due to the excessively low temperature, electrolysis products easily precipitated, causing blockage of the pipeline after 20 minutes of operation, forcing the termination of electrolysis.

[0088] Table 1: Comparison of Electrolysis Performance

[0089]

[0090] As can be seen from Table 1, when the tank voltage is 1V, the performance of all embodiments is good, with Embodiment 1 being the best.

[0091] The above description is merely a few embodiments and comparative examples of this application, and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

Claims

1. A device for the electrocatalytic oxidation of hydroquinone to p-benzoquinone coupled with water electrolysis cathode hydrogen production, characterized in that: The mixed water electrolysis device includes a membrane electrode placed between two plates. The membrane electrode includes a cathode catalyst layer, a diaphragm, and an anode catalyst layer stacked together. The two plates are respectively attached to the surfaces on both sides of the membrane electrode. The two plates have a flow field on the side facing the membrane electrode for the electrolyte to flow through. The cathode electrolyte is introduced into the flow field through the inlet of the flow field on the plate near the cathode catalyst layer on the membrane electrode, flows through the flow field and the cathode catalyst layer, and then flows out through the outlet of the flow field. The anolyte is introduced into the flow field through the inlet of the flow field on the plate near the anolyte catalyst layer on the membrane electrode, flows through the flow field and the anolyte catalyst layer, and then flows out through the outlet of the flow field. The anolyte is an inorganic acid solution containing the organic substrate hydroquinone, and the catholyte is an inorganic acid solution.

2. The apparatus according to claim 1, characterized in that: The inorganic acid in the anolyte is an aqueous solution of one or two of sulfuric acid and perchloric acid; the concentration of the inorganic acid is 0.1 mol / L to 2 mol / L. Preferably, the inorganic acid is sulfuric acid, and the concentration of sulfuric acid is 0.2 mol / L to 1 mol / L.

3. The apparatus according to claim 1, characterized in that: The concentration of the substrate hydroquinone was 0.04 mol / L to 0.3 mol / L; Preferably, the hydroquinone concentration is 0.2 mol / L to 0.3 mol / L.

4. The apparatus according to claim 1, characterized in that: The cathode electrolyte is an aqueous solution of one or two of sulfuric acid or perchloric acid, with a concentration of 0.1 mol / L to 2 mol / L; Preferably, the cathode electrolyte is sulfuric acid with a concentration of 0.2 mol / L to 1 mol / L.

5. The apparatus according to claim 1, characterized in that: The anode catalyst layer includes an anode catalyst and an ionomer; the anode catalyst is one or more of manganese dioxide, iridium oxide, platinum ruthenium carbon, and platinum carbon; the ionomer is Nafion; the mass ratio of the anode catalyst to the ionomer is 20:1 to 5:1; Preferably, the anode catalyst is platinum-ruthenium carbon, and the mass ratio of platinum-ruthenium carbon to ionomer is 12:1 to 8:

1.

6. The apparatus according to claim 1, characterized in that: The cathode catalyst layer includes a cathode catalyst and an ionomer; the cathode catalyst is one or more of platinum-ruthenium carbon and platinum carbon; the ionomer is Nafion; the mass ratio of the cathode catalyst to the ionomer is 20:1 to 5:1; preferably, the cathode catalyst is platinum-ruthenium carbon, and the mass ratio of platinum-ruthenium carbon to the ionomer is 12:1 to 8:

1.

7. The apparatus according to claim 1, characterized in that: A diaphragm is a proton exchange membrane that conducts protons, including the Nafion membrane.

8. The apparatus according to claim 1, characterized in that: The membrane electrode is prepared by coating a slurry containing an anode catalyst and Nafion or a slurry containing a cathode catalyst and Nafion onto a support to obtain an anode catalyst layer and a cathode catalyst layer. Then, the catalyst-coated sides of the anode catalyst layer and the cathode catalyst layer are stacked with the membrane, either separately or simultaneously, to obtain the membrane electrode. Preferably, the carrier is selected from one or more of the following: nickel foam mesh, carbon paper, carbon felt, titanium felt, and titanium mesh.

9. The apparatus according to claim 1, characterized in that: The device is composed of a cathode plate with a serpentine flow field, an annular fluororubber sheet, a membrane electrode, an annular fluororubber sheet, and an anode plate with a serpentine flow field stacked in sequence to form a zero-gap water electrolysis cell; an electric heating element and a thermocouple are respectively provided in the two electrode plates; The electric heating element is a heating wire or heating rod. The thermocouple is connected to an external temperature controller via a wire. The electric heating element is connected to an external power source via a wire through the external temperature controller. The device further includes a cathode electrolyte storage tank containing cathode electrolyte, wherein the cathode electrolyte is connected to the inlet of the flow field of the cathode plate via a pump and a pipeline, and the outlet of the flow field of the cathode plate is connected to the cathode electrolyte storage tank via a pipeline; the device further includes an anolyte storage tank containing anolyte, wherein the anolyte is connected to the inlet of the flow field of the anode plate via a pump and a pipeline, and the outlet of the flow field of the anode plate is connected to the anolyte storage tank via a pipeline.

10. The application of the device according to any one of claims 1-9, characterized in that: The device is used for the combined production of p-benzoquinone and hydrogen, and operates at a temperature of 30–90°C.

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