Electrode material and preparation method and application thereof

Abstract

The invention discloses an electrode material and a preparation method and application thereof. The electrode material comprises a conductive substrate, metal elements ruthenium and zinc located on the conductive substrate, and any one, two or more than two of non-metal elements carbon, nitrogen, sulfur and boron located on the conductive substrate. According to the electrode material provided by the invention, through reasonable design, an electronic structure can be effectively adjusted, charge separation and transmission can be enhanced, and cycloheximine can be removed through a direct electron transfer mediation mode.

Description

Technical Field

[0001] The present invention belongs to the field of water treatment, and more specifically, relates to an electrode material and a preparation method and application thereof. Background Art

[0002] Hexamethyleneimine is an important organic intermediate with widespread applications in pesticides, pharmaceuticals, rubber products, and textiles. However, it is also a highly toxic pollutant. At concentrations exceeding 80 mg / L in water, it can inhibit microbial metabolism. Furthermore, hexamethyleneimine wastewater typically contains high levels of total nitrogen and COD. Directly entering a biochemical system without pretreatment can lead to system failure.

[0003] At present, there are many treatment methods for cycloheximide wastewater at home and abroad. Patent (CN102153163 B) discloses a method for treating wastewater containing cycloheximide and hexamethylenediamine using a fiber adsorbent. The fiber adsorbent used has the advantage of a high total nitrogen removal rate. However, the actual cycloheximide wastewater also has a high COD (up to 6000 mg / L). High COD conditions may affect the adsorption of cycloheximide by the fiber adsorbent; and the use of hydrochloric acid desorption may also cause secondary pollution. Patent (CN105439262 B) discloses a pretreatment method for wastewater containing organic amines. The method "contacts a water-soluble inorganic substance that provides heteropolyacid heteroatoms and a water-soluble inorganic salt that provides heteropolyacid polyatoms with wastewater containing organic amines under acidic conditions, and separates a precipitate after standing." However, the precipitate still needs post-processing to further reduce the environmental risks of cycloheximide. In addition, the principles of the above patents are all based on physical processes. Although the process can transfer or concentrate pollutants, it does not achieve "decontamination" in the true sense. Therefore, developing chemical methods to treat cycloheximide wastewater is of far-reaching significance.

[0004] In recent years, electrochemical advanced oxidation technology has attracted attention due to its advantages such as simple operation, high stability, and wide pH range. Conventional electrochemical systems can achieve the oxidation of organic nitrogen and ammonia nitrogen at the anode, while reducing nitrate nitrogen to nitrogen gas at the cathode, achieving the effect of removing total nitrogen from wastewater. However, the stability of cycloheximide molecules gives it antioxidant properties, making it difficult to effectively degrade it using conventional electrochemical oxidation technologies. In addition, the high COD characteristics of cycloheximide wastewater mentioned above further affect the oxidation of cycloheximide at the anode. Therefore, there is an urgent need to develop an electrochemical technology that can selectively remove cycloheximide and thus achieve total nitrogen removal from wastewater. Summary of the Invention

[0005] 1. Problem to be solved

[0006] Aiming at the problem that the existing electrode materials have unsatisfactory effects in degrading cycloheximide, the present invention provides an electrode material, as well as a preparation method of the electrode material and an application of the electrode material in degrading cycloheximide.

[0007] 2. Technical solution

[0008] In order to solve the above problems, the technical solutions adopted by the present invention are as follows:

[0009] A first aspect of the present invention provides an electrode material, comprising:

[0010] A substrate, wherein the substrate is a conductive substrate;

[0011] and, a metal element on the conductive substrate, the metal element comprising ruthenium and zinc;

[0012] and, a non-metallic element located on the conductive substrate;

[0013] Wherein, calculated as metal elements, the molar ratio of ruthenium to zinc is (1-5):1.

[0014] As a preferred embodiment of any embodiment of the first aspect of the present invention, the molar ratio of ruthenium to zinc is 2:1.

[0015] As a preferred embodiment of any embodiment of the first aspect of the present invention, the non-metallic element includes any one, two or more of carbon, nitrogen, sulfur and boron.

[0016] As a preferred embodiment of any embodiment of the first aspect of the present invention, the non-metallic elements include carbon and nitrogen.

[0017] As a preferred embodiment of any embodiment of the first aspect of the present invention, the non-metallic elements include carbon, nitrogen, and sulfur.

[0018] As a preference in any embodiment of the first aspect of the present invention, the conductive substrate is a conductive substrate containing titanium.

[0019] As a preference in any embodiment of the first aspect of the present invention, the conductive substrate is a titanium substrate.

[0020] A second aspect of the present invention provides a method for preparing an electrode material, comprising the steps of:

[0021] S1. Preparing a conductive substrate and a precursor liquid, wherein the precursor liquid contains a metal element ruthenium, zinc, and a non-metallic element;

[0022] S2. The conductive substrate is immersed in a precursor liquid and subjected to a hydrothermal reaction under sealed conditions;

[0023] S3. calcining the conductive substrate after the hydrothermal reaction at high temperature.

[0024] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the molar ratio of ruthenium, zinc, and non-metallic elements is 2:1:(1-12) calculated based on the sum of non-metallic elements; the concentration of ruthenium in the precursor liquid is 0.02 mol / L.

[0025] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the concentration of ruthenium in the precursor liquid is 0.015-0.03 mol / L, preferably 0.015-0.025 mol / L, and more preferably 0.018-0.022 mol / L.

[0026] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the concentration of zinc in the precursor liquid is 0.005-0.02 mol / L, preferably 0.008-0.015 mol / L, and more preferably 0.008-0.012 mol / L.

[0027] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the concentration of the non-metallic element in the precursor liquid is 0.01-0.12 mol / L, preferably 0.03-0.1 mol / L, and more preferably 0.04-0.1 mol / L.

[0028] Based on the above-mentioned concentrations of ruthenium, zinc, and non-metallic elements in the precursor liquid, the conductive substrate only needs to be completely immersed in the precursor liquid.

[0029] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the conductive substrate is pretreated, and the pretreatment includes polishing and cleaning.

[0030] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the conductive substrate is pretreated, and the pretreatment includes degreasing, grinding, pickling, and drying; further, the drying temperature is 30 to 80°C.

[0031] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the non-metallic element includes any one, two or more of carbon, nitrogen, sulfur and boron.

[0032] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the raw material containing the non-metallic element includes any one or more of sucrose, glucose, urea, boric acid, and thiourea.

[0033] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the raw material containing the metal element ruthenium includes a ruthenium salt, typically ruthenium chloride, ruthenium sulfate, or ruthenium nitrate.

[0034] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S1, the raw material containing the metallic element zinc includes zinc salts, typically zinc chloride, zinc sulfate, and zinc nitrate.

[0035] As a preferred embodiment of any embodiment of the second aspect of the present invention, the molar ratio of the raw material containing the metal element ruthenium, the raw material containing the metal element zinc, and the raw material containing the non-metallic element is 2:1:(1-3).

[0036] As a preferred embodiment of any embodiment of the second aspect of the present invention, the molar ratio of the raw material containing the metal element ruthenium, the raw material containing the metal element zinc, and the raw material containing the non-metallic element is 2:1:(1-2.5).

[0037] As a preferred embodiment of any embodiment of the second aspect of the present invention, the molar ratio of the raw material containing the metal element ruthenium, the raw material containing the metal element zinc, and the raw material containing the non-metallic element is 2:1:(1-2).

[0038] As a preferred embodiment of any embodiment of the second aspect of the present invention, the concentration of the raw material containing the metal element ruthenium is 0.015-0.03 mol / L, preferably 0.015-0.025 mol / L, and more preferably 0.018-0.022 mol / L.

[0039] As a preferred embodiment of any embodiment of the second aspect of the present invention, the concentration of the raw material containing the metal element zinc is 0.005-0.02 mol / L, preferably 0.008-0.015 mol / L, and more preferably 0.008-0.012 mol / L.

[0040] As a preferred embodiment of any embodiment of the second aspect of the present invention, the concentration of the raw material containing the non-metallic element is 0.01 to 0.03 mol / L, preferably 0.012 to 0.025 mol / L.

[0041] Based on the concentrations of the raw material containing the metal element ruthenium, the raw material containing the metal element zinc, and the non-metallic element in the precursor liquid, the conductive substrate only needs to be completely immersed in the precursor liquid.

[0042] As a preference of any embodiment of the second aspect of the present invention, in step S2, the heating temperature of the hydrothermal reaction is 100-180°C, and the reaction time is 1-4 hours.

[0043] As a preferred embodiment of any embodiment of the second aspect of the present invention, in step S3, the holding temperature of the high-temperature calcination is 300-600° C., and the holding time is 2-4 hours.

[0044] The third aspect of the present invention provides the use of the electrode material described in any embodiment of the first aspect of the present invention, or the electrode material prepared by the method described in any embodiment of the second aspect of the present invention as an electrode in the electrochemical degradation of cycloheximide.

[0045] As a preferred embodiment of any embodiment of the third aspect of the present invention, the conditions of the electrochemical action include a pH of 5 to 12, a current density of 10 to 25 mA / cm 2 .

[0046] As a preferred embodiment of any embodiment of the third aspect of the present invention, the wastewater quality is: COD>5000 mg / L, total nitrogen>500 mg / L, cycloheximide concentration>1000 mg / L.

[0047] As a preferred embodiment of any embodiment of the third aspect of the present invention, the wastewater quality is: COD 5000-9000 mg / L, total nitrogen 500-2500 mg / L, cycloheximide concentration 1000-2000 mg / L.

[0048] Beneficial effects

[0049] (1) The electrode material provided by the present invention comprises a conductive substrate and metal elements ruthenium and zinc, and non-metallic elements (including carbon and / or nitrogen and / or sulfur and / or boron) located on the conductive substrate. The metal elements ruthenium and zinc self-assemble to form a charge redistribution, so that the free electrons on the metal surface can undergo a directionally migrated state under the drive of an electric field. In addition, the doping of non-metallic heteroatoms can, on the one hand, further regulate the charge distribution on the surface of the electrode material. Specifically, electron transfer occurs between ruthenium, zinc and non-metals due to the electronegativity effect, resulting in local electron-rich regions and electron-poor regions, thereby accelerating electron transfer; on the other hand, it can stabilize the metal active components.

[0050] (2) The electrode material provided by the present invention can effectively adjust the electronic structure through rational design, enhance charge separation and transfer, and remove cycloheximide through direct electron transfer. Cycloheximide undergoes ring opening on the electrode surface, which can effectively avoid the interference of high COD in actual wastewater while also having the ability to remove ammonia nitrogen, meeting the water inlet requirements of subsequent biochemical treatment of wastewater or meeting the discharge standards.

[0051] In addition, the electrode material provided by the present invention has high selectivity for the removal of cycloheximide, which can greatly reduce energy consumption and drug consumption, while reducing the consumption of valuable substances in wastewater, which is in line with the "dual carbon" concept.

[0052] (3) The preparation method of the electrode material provided by the present invention has a simple process, does not require expensive equipment, and is flexible and controllable. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 When the electrode material prepared in Example 1 of the present invention is used as an anode to treat simulated cycloheximide wastewater, the cycloheximide removal rate and COD concentration change over time;

[0054] Figure 2 When the electrode material prepared in Example 2 of the present invention is used as an anode to treat actual cycloheximide wastewater, the concentration of cycloheximide, COD concentration, organic nitrogen concentration, ammonia nitrogen concentration and nitrate nitrogen concentration change over time;

[0055] Figure 3 A comparison chart of cycloheximide removal efficiency when the electrode materials prepared in Example 2, Example 3, Comparative Example 4 and Comparative Example 5 of the present invention are used as anodes to treat actual cycloheximide wastewater;

[0056] Figure 4 These are characterization diagrams of electrochemical active area detection of electrode materials prepared in Example 1, Example 3, Comparative Example 1, Comparative Example 2, and Comparative Example 3 of the present invention.

[0057] Definition

[0058] Unless otherwise defined, in the present invention, all technical and scientific terms used have the same meaning as commonly understood by those skilled in the art to which the present invention belongs; the term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0059] In the present invention, if the specific conditions are not specified in the examples, the experiments were carried out according to conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used, if the manufacturer is not specified, are all conventional products that can be purchased from the market.

[0060] As used herein, the term "about" is used to provide flexibility and imprecision associated with a given term, measurement, or value. One skilled in the art can readily determine the degree of flexibility for a particular variable.

[0061] Example 1

[0062] The preparation method of the electrode material is as follows:

[0063] Step 1: Select a titanium plate with a length, width and thickness (L×W×H) of 30×30×1 mm as the substrate, pre-treat the titanium substrate by degreasing, polishing, pickling, etc., and then place it in a 70°C oven for drying.

[0064] Step 2: At room temperature, weigh 0.5229 g (0.002 mol) of ruthenium chloride trihydrate, 0.1363 g (0.001 mol) of zinc chloride, and 0.1522 g (0.002 mol, totaling 0.008 mol of carbon, nitrogen, and sulfur) of thiourea, and add them to 100 mL of a 10 wt% ethanol solution to prepare a precursor solution.

[0065] Step 3: Immerse the pretreated titanium plate obtained in step 1 in the precursor solution obtained in step 2, and transfer them together to a hydrothermal reactor for hydrothermal reaction at 150°C for 2 hours. After the reaction is completed, place the titanium plate in a 70°C oven and dry it for 10 hours.

[0066] Step 4: Place the titanium plate obtained in step 3 in a muffle furnace, heat the temperature to 450°C at a heating rate of 3°C / min in an air atmosphere, bake for 2 hours, and then cool to room temperature to obtain a non-metallic element (carbon, nitrogen, sulfur) doped ruthenium-zinc bimetallic titanium electrode material.

[0067] Step 5: Prepare simulated cycloheximide wastewater with the following water qualities: COD concentration 6285 mg / L, total nitrogen concentration 550 mg / L, and cycloheximide concentration 1000 mg / L. Use the electrode material prepared in Step 4 as the anode for electrochemical oxidation of cycloheximide. Electrochemical oxidation conditions are pH 9, temperature 25°C, sodium chloride as the electrolyte, and a current density of 10 mA / cm 2 .

[0068] from Figure 1 It can be seen that the electrode material provided in Example 1 is used as an anode to treat cycloheximide. After 8 hours of electrochemical oxidation, the removal rate of cycloheximide at a gram-level per liter concentration reaches 94.18%, showing strong anti-COD interference ability; in addition, the COD removal rate is only 14.56%, indicating that the electrode material provided in Example 1 is highly selective for the removal of cycloheximide.

[0069] Example 2

[0070] The electrode material prepared in Example 1 was applied to the treatment of cycloheximide wastewater. The actual wastewater quality was a COD concentration of 8300 mg / L, a total nitrogen concentration of 1350 mg / L, and a cycloheximide concentration of 1800 mg / L. The electrochemical oxidation conditions were pH 8, a temperature of 25°C, sodium chloride as the electrolyte, and a current density of 15 mA / cm 2 .

[0071] from Figure 2 It can be seen that the anode material prepared in Example 1 can effectively cope with the complex environment of actual wastewater, and can remove ammonia nitrogen while degrading cycloheximide, ensuring that the total nitrogen in the electrochemically oxidized effluent meets the subsequent treatment requirements.

[0072] Example 3

[0073] Step 1: Select a titanium plate with a length, width and thickness (L×W×H) of 30×30×1 mm as the substrate, pre-treat the titanium substrate by degreasing, polishing, pickling, etc., and then place it in a 70°C oven for drying.

[0074] Step 2: At room temperature, weigh 0.5229 g (0.002 mol) of ruthenium chloride trihydrate, 0.1363 g (0.001 mol) of zinc chloride, and 0.090 g (0.0015 mol, carbon and nitrogen totaling 0.0045 mol) of urea, add them to 100 mL of a 10 wt% ethanol solution to prepare a precursor solution.

[0075] Step 3: Immerse the pretreated titanium plate obtained in step 1 in the precursor solution obtained in step 2, and transfer them together to a hydrothermal reactor for hydrothermal reaction at 180°C for 2 hours. After the reaction is completed, place the titanium plate in a 70°C oven and dry it for 10 hours.

[0076] Step 4: Place the titanium plate obtained in step 3 in a muffle furnace, raise the temperature to 600°C at a heating rate of 5°C / min in an air atmosphere, bake for 4 hours, and then cool to room temperature to obtain a non-metallic element (carbon, nitrogen) doped ruthenium-zinc bimetallic titanium electrode material.

[0077] Step 5: The prepared electrode material was used as the anode in the electrochemical oxidation treatment of cycloheximide wastewater. The actual wastewater quality was 8300 mg / L COD, 1350 mg / L total nitrogen, and 1800 mg / L cycloheximide. The electrochemical oxidation conditions were pH 8, 25°C temperature, sodium chloride electrolyte, and a current density of 15 mA / cm 2 .

[0078] from Figure 3 It can be seen that the ruthenium and zinc bimetallic active sites can better maintain the removal rate of cycloheximide.

[0079] Comparative Example 1

[0080] The process is basically the same as Example 1, except for step 2. Step 2 in this comparative example is as follows:

[0081] 0.5229 g (0.002 mol) of ruthenium chloride trihydrate and 0.1363 g (0.001 mol) of zinc chloride were weighed and added to 100 mL of a 10 wt% ethanol solution at room temperature to prepare a precursor solution.

[0082] Comparative Example 2

[0083] The process is basically the same as Example 1, except for step 2. Step 2 in this comparative example is as follows:

[0084] 0.5229 g (0.002 mol) of ruthenium chloride trihydrate, 0.1363 g (0.001 mol) of zinc chloride, and 0.3044 g (0.004 mol) of thiourea were weighed and added to 100 mL of a 10 wt% ethanol solution at room temperature to prepare a precursor solution.

[0085] Comparative Example 3

[0086] The process is basically the same as Example 1, except for step 2. Step 2 in this comparative example is as follows:

[0087] 0.5229 g (0.002 mol) of ruthenium chloride trihydrate, 0.1363 g (0.001 mol) of zinc chloride, and 0.6088 g (0.008 mol) of thiourea were weighed and added to 100 mL of a 10 wt% ethanol solution at room temperature to prepare a precursor solution.

[0088] Comparative Example 4

[0089] The same as Example 2, the only difference is the electrochemical oxidation conditions. The electrochemical oxidation conditions in this comparative example are as follows:

[0090] The electrochemical oxidation conditions were pH 11, temperature 25°C, electrolyte sodium chloride, and current density 15 mA / cm 2 .

[0091] Comparative Example 5

[0092] The same as Example 2, the only difference is the electrochemical oxidation conditions. The electrochemical oxidation conditions in this comparative example are as follows:

[0093] The electrochemical oxidation conditions were pH 3, temperature 25°C, electrolyte sodium chloride, and current density 15 mA / cm 2 .

[0094] The above description is to be considered as a description of specific embodiments only. Those skilled in the art and those who make or use the present invention will appreciate variations of the present invention. Therefore, it should be understood that the embodiments shown in the drawings and described above are for illustrative purposes only and are not intended to limit the scope of the present invention.

Claims

1. An electrode material, characterized in that The electrode material includes: A substrate, wherein the substrate is a conductive substrate; and, a metal element on the conductive substrate, the metal element comprising ruthenium and zinc; and, non-metallic elements located on the conductive substrate, wherein the non-metallic elements include any one, two or more of carbon, nitrogen, sulfur and boron; Wherein, calculated as metal elements, the molar ratio of ruthenium to zinc is (1-5):

1.

2. The electrode material according to claim 1, characterized in that The conductive substrate is a conductive substrate containing titanium.

3. A method for preparing an electrode material, characterized in that: Including steps: S1. Prepare a conductive substrate and a precursor liquid, wherein the precursor liquid contains metal elements ruthenium, zinc, and non-metallic elements, wherein the non-metallic elements include any one, two or more of carbon, nitrogen, sulfur, and boron; The molar ratio of ruthenium, zinc, and non-metallic elements is 2:1:(1-12) calculated based on the total amount of non-metallic elements; and the concentration of ruthenium in the precursor liquid is 0.015-0.03 mol / L. S2. The conductive substrate is immersed in a precursor liquid and subjected to a hydrothermal reaction under sealed conditions; S3. calcining the conductive substrate after the hydrothermal reaction at high temperature.

4. The method for preparing the electrode material according to claim 3, wherein: In step S1, the conductive substrate is pretreated, and the pretreatment includes polishing and cleaning.

5. The method for preparing the electrode material according to claim 3, wherein: In step S1, the raw material containing the non-metallic element includes any one or more of sucrose, glucose, urea, boric acid, and thiourea; The raw material containing the metal element ruthenium includes ruthenium salt; The raw materials containing the metallic element zinc include zinc salts.

6. The method for preparing an electrode material according to any one of claims 3 to 5, characterized in that: The molar ratio of the raw material containing the metal element ruthenium, the raw material containing the metal element zinc, and the raw material containing the non-metallic element is 2:1:(1-2).

7. The method for preparing the electrode material according to claim 6, wherein: In step S2, the heating temperature of the hydrothermal reaction is 100-180°C; The reaction time is 1 to 4 hours.

8. The method for preparing the electrode material according to claim 6, wherein: In step S3, the holding temperature of the high-temperature calcination is 300-600° C.; The insulation time is 2 to 4 hours.

9. Use of the electrode material according to any one of claims 1 to 2, or the electrode material prepared by the method according to any one of claims 3 to 8, in the electrochemical degradation of cycloheximide.

10. The use according to claim 9, characterized in that The conditions of the electrochemical action include: pH 5-12; Current density is 10~25mA / cm 2 .

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