A cathode material for treating medical and chemical industrial wastewater based on active hydrogen regulation and a preparation method and application thereof

Abstract

The application discloses a kind of medical and chemical industry wastewater treatment cathode material based on active hydrogen regulation and its preparation method and application, the preparation method of the cathode material includes: pretreatment to titanium sheet, then with it as anode, untreated titanium sheet is cathode, is immersed in the electrolytic aqueous solution containing sodium fluoride-sodium bisulfate, carries out anodic oxidation corrosion treatment under electrolysis, again heat treatment is carried out in air atmosphere, the obtained electrode material is used as working electrode, platinum sheet electrode, inert electrode such as graphite electrode is used as counter electrode, Co (OH) 2 layer is obtained by electrodeposition in the electrodeposition liquid containing Co salt and sodium sulfate, then heat treatment is carried out in air atmosphere, finally, impregnation sulfidation treatment is carried out, that is, preparation is completed.The electrode material prepared by the application has the chemical stability of Co3O4 and high redox performance, further enhances the catalytic activity of mesoporous Co3O4, and has good catalytic degradation effect on medical and chemical industry wastewater.

Description

Technical Field

[0001] This invention relates to the field of pharmaceutical and chemical wastewater treatment technology, specifically to a cathode material for pharmaceutical and chemical wastewater treatment based on active hydrogen regulation, its preparation method, and its application. Background Technology

[0002] Pharmaceutical and chemical wastewater is one of the most challenging aspects of industrial wastewater treatment, characterized by its complex pollution features and significant hazards. Firstly, the wastewater composition is highly complex, containing large amounts of recalcitrant organic matter, toxic substances, and high concentrations of salt. Nitrobenzene compounds, a typical pollutant in pharmaceutical and chemical wastewater, are particularly hazardous. Nitrobenzene compounds are a class of organic compounds with nitro substituents, including nitrobenzene, nitrobenzene, and nitrobenzene. Their high toxicity, carcinogenicity, and bioaccumulation pose a potential threat to ecological stability and human health. Commonly used methods for treating nitrobenzene pollutants include adsorption, solvent extraction, advanced oxidation, and biodegradation. However, these methods generally suffer from high costs, secondary pollution, and high energy consumption. Active hydrogen electron reduction technology exhibits higher selectivity, environmental friendliness, and safety in pollutant degradation, making it especially suitable for treating highly toxic and recalcitrant substances such as nitrobenzene. Compared to traditional methods, it eliminates the need for external strong oxidants or hazardous reducing agents (such as sodium borohydride), significantly reducing costs and the risk of secondary pollution, making it an important development direction in the field of pharmaceutical and chemical wastewater treatment.

[0003] Titanium substrates possess comprehensive advantages such as corrosion resistance, conductivity, mechanical strength, long lifespan, and multifunctionality, making them an ideal replacement for traditional electrodes (such as graphite and lead-based electrodes). However, a dense oxide film easily forms on the titanium surface, leading to increased resistance. Furthermore, the oxide film reduces the adhesion between the catalyst layer and the titanium substrate, increasing the likelihood of catalyst layer detachment. Therefore, the presence of a transition layer can effectively prevent titanium surface oxidation and enhance the adhesion of the catalyst layer. Nanostructured Co3O4 catalysts have attracted significant attention in recent years due to their large surface area and efficient electron transfer and utilization. Summary of the Invention

[0004] The purpose of this invention is to provide a cathode material for pharmaceutical and chemical wastewater treatment based on active hydrogen regulation, its preparation method, and its application. A high-efficiency electrocatalytic material of non-metallic sulfur-doped cobalt tetroxide is prepared by regulating the ligands. In a single-chamber electrolyzer without an external hydrogen source, an electrocatalytic cathode reduction technology based on the regulation of active hydrogen and electron transport pathways is developed. The reduction effect of electrons generated by direct water electrolysis at the cathode electrode and active hydrogen (H*) on acetaminophen (APAP) is studied. The effects of electrodeposition time, electrodeposition voltage, calcination temperature, and sulfidation time on the APAP reduction effect are further investigated. The prepared electrode material possesses the chemical stability and high redox performance of Co3O4. Furthermore, by doping with non-metals to improve its electronic structure, the catalytic activity of mesoporous Co3O4 can be further enhanced. In application, energy consumption is reduced, production costs are lowered, and secondary pollution is avoided, achieving the operational goals of high efficiency, low energy consumption, and environmental friendliness.

[0005] The technical solution adopted in this invention is as follows:

[0006] A method for preparing a cathode material for treating pharmaceutical and chemical wastewater based on active hydrogen regulation includes the following steps:

[0007] Step S1 Titanium sheet pretreatment: First, the titanium sheet is mechanically polished and acid-base cleaned, and then a clean and rough titanium substrate is prepared by ultrasonic-assisted chemical acid etching process.

[0008] Step S2: Using the titanium substrate obtained in step S1 as the anode and the untreated titanium sheet as the cathode, immerse it in an electrolytic aqueous solution containing sodium fluoride and sodium bisulfate for anodic oxidation corrosion treatment to form a titanium dioxide nanolayer on the titanium substrate. Then remove it, clean it, and let it air dry naturally.

[0009] Step S3: The titanium material obtained in step S2 is heat-treated in an air atmosphere to obtain a titanium dioxide nano-transition layer electrode material with good thermal stability.

[0010] Step S4: Using the titanium dioxide nano-transition layer electrode material obtained in step S3 as the working electrode, inert conductive electrodes such as platinum sheet electrodes and graphite electrodes as the counter electrode, and a saturated calomel electrode as the reference electrode, a proton exchange membrane is used to separate the cathode and anode. A Co(OH)2 layer is electrodeposited in an electrodeposition solution containing Co salt and sodium sulfate, and then heat-treated in an air atmosphere to obtain Co3O4 / TiO2-Ti.

[0011] Step S5: The Co3O4 / TiO2-Ti prepared in step S4 is placed in a sodium sulfide solution and impregnated in a water bath. Then, it is heat-treated under an inert atmosphere to finally obtain the material S-Co3O4 / TiO2-Ti, which completes the preparation.

[0012] Further, the specific process of step S1 is as follows: First, the titanium sheet is polished with a grinding wheel and sandpaper, then cleaned with a 35-45% sodium hydroxide solution for 20-40 minutes, and then boiled in a 15-25% sulfuric acid solution for 30-50 minutes; next, the titanium sheet is cleaned with ultrapure water, dried, and then immersed in a 10-20% oxalic acid solution. It is then placed in an ultrasonic cleaner and ultrasonically etched at a temperature of 20-40°C for 10-30 minutes.

[0013] Further, in step S2, the sodium fluoride mass concentration in the electrolytic aqueous solution is 0.3-0.5 wt%, the sodium bisulfate mass concentration is 6-8 wt%, the anodic oxidation corrosion treatment temperature is 50-70℃, the treatment voltage is 20-40V, and the anodic oxidation time is 10-30min.

[0014] Furthermore, in step S3, the heat treatment temperature is 350-550℃, preferably 400-450℃, and the heat treatment time is 2-4 hours.

[0015] Further, in step S4, the concentration of Co in the electrodeposition solution is 0.05-0.2M, the concentration of sodium sulfate is 0.05-0.2M, the electrodeposition voltage is -0.9--1.3V, and the electrodeposition time is 10-60min, preferably 30-40min.

[0016] Furthermore, in step S4, the heat treatment temperature is 300-500℃, preferably 400±50℃, and the heat treatment time is 0.5-2h.

[0017] Further, in step S5, the concentration of the sodium sulfide solution is 0.05-0.2M, the immersion temperature is 50-70℃, and the immersion time is 1-6h; the heat treatment temperature in step S5 is 350-450℃, and the heat treatment time is 1-4h.

[0018] The present invention also discloses the application of the cathode material in the electrocatalytic treatment of pharmaceutical and chemical wastewater, characterized in that the cathode material generates active hydrogen during the electrolysis process, and the active hydrogen and the electrons generated by the electrolysis serve as active components for the degradation, catalytic reduction and degradation of pharmaceutical and chemical wastewater.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] (1) The present invention prepares sulfur-doped cobalt tetroxide catalytic cathode S-Co3O4 / TiO2 / Ti by direct current electro-corrosion, high-temperature calcination in a tubular furnace, and a relatively simple electrodeposition method. The sulfur-doped cobalt tetroxide catalytic cathode prepared by the method of the present invention is placed in a reactor for electrocatalytic reduction treatment of organic wastewater. The active hydrogen generated by electrons and cathodes catalyzes the action of acetaminophen (APAP).

[0021] (2) By changing the electrodeposition voltage (-0.9, -1.1, -1.3V) and electrodeposition time (10, 20, 30, 60min), the optimal electrodeposition voltage was determined to be -0.9V and the optimal electrodeposition time to be 30min. The results are as follows: Figure 1 As shown, when the potential increases to -1.1 and -1.3V, the electrodeposited Co(OH)₂ film is prone to rupture and detachment due to the large amount of H₂ generated on the Ti substrate. This detachment is particularly pronounced after calcination in a tube furnace, as shown in the following results. Figure 2 As shown. If the electrodeposition time is too short, the substrate cannot be completely covered; if the time is too long, the Co(OH)2 film is prone to rupture.

[0022] (3) The cathode material prepared by the present invention has a high removal rate of APAP and chemical oxygen demand (COD) in a single-chamber electrolytic cell, and has high stability for repeated use. Attached Figure Description

[0023] Figure 1 The effect of different electrodeposition times on the electrode sheet is shown from left to right as 10, 20, 30, and 60 min.

[0024] Figure 2 The images show the Co3O4 / TiO2 / Ti materials after pyrolysis following electrodeposition under different voltage conditions. From left to right, the voltages correspond to the electrodeposition voltage conditions of -0.9, -1.1, and -1.3V, respectively.

[0025] Figure 3 Field emission scanning electron microscopy (FESEM) of the catalytic cathodes S-Co3O4 / TiO2 / Ti prepared for different sulfidation times in Example 2, where (a-e) sulfidation times are 1, 2, 4, 6, and 8 h, respectively;

[0026] Figure 4a FESEM image of Co(OH)2 / TiO2 / Ti-x obtained by calcination at 300℃;

[0027] Figure 4b FESEM image of Co(OH)2 / TiO2 / Ti-x obtained by calcination at 400℃;

[0028] Figure 4cThe image shows the FESEM image of Co(OH)2 / TiO2 / Ti-x obtained by calcination at 500℃.

[0029] Figure 5a This is a graph showing the effect of different electrode materials on APAP removal rate in Comparative Example 1.

[0030] Figure 5b This is a graph showing the effect of different electrode materials on COD removal rate in Comparative Example 1.

[0031] Figure 6a This is a graph showing the effect of the same sulfidation time on the APAP removal rate in Comparative Example 2.

[0032] Figure 6b This is a graph showing the effect of sulfidation time on COD removal rate in Comparative Example 2.

[0033] Figure 7a This is a graph showing the effect of different current densities on APAP removal rate in Comparative Example 3.

[0034] Figure 7b This is a graph showing the effect of different current densities on COD removal rate in Comparative Example 3.

[0035] Figure 8a Comparative Example 4 shows the effect of initial APAP concentration on APAP removal rate;

[0036] Figure 8b Comparative Example 4 shows the effect of initial APAP concentration on COD removal rate; Detailed Implementation

[0037] Example 1

[0038] Step S1: The electrode substrate is a 1×3cm titanium sheet. First, the titanium sheet is polished with a grinding wheel and sandpaper (600 grit and 1200 grit), then cleaned with a 40% sodium hydroxide aqueous solution for 30 minutes, and then boiled in a 20% sulfuric acid solution for 40 minutes. Next, the titanium sheet is cleaned with ultrapure water, ultrasonically treated for 15 minutes, dried, and then vertically immersed in a 15% oxalic acid solution (avoid stacking). It is then placed in an ultrasonic cleaner and ultrasonically etched at 30°C for 20 minutes to obtain the pretreated Ti sheet.

[0039] Step S2: Using the "pretreated Ti sheet" from step S1 as the anode and a titanium sheet of the same area as the cathode, immerse it in a mixed electrolytic aqueous solution containing 0.3wt% sodium fluoride and 8wt% sodium bisulfate. Treat it for 30 minutes at a voltage of 30V and an anodizing corrosion treatment temperature of 60℃. Then rinse it with deionized water and let it air dry naturally.

[0040] Step S3: The titanium dioxide nanolayer electrode plate prepared in step S2 is placed in a tube furnace and calcined in air atmosphere. The temperature is increased from room temperature to 450℃ at a rate of 2℃ / min, and then calcined at a constant temperature for 4h. Then it is naturally cooled to room temperature to obtain a stable titanium dioxide nanotransition layer. The obtained material is denoted as TiO2 / Ti titanium sheet material.

[0041] In step S4, using the TiO2 / Ti titanium sheet material obtained in step S3 as the working electrode in a three-electrode system, a platinum sheet of the same area as the counter electrode, a saturated calomel electrode as the reference electrode, and a proton exchange membrane as a separator to separate the working electrode and the counter electrode, a Co(OH)2 layer is obtained by electrodeposition for 30 min in an electrolytic aqueous solution containing 0.05 M cobalt nitrate and 0.1 M sodium sulfate at a voltage of -0.9 V using an electrochemical workstation. The obtained Co(OH)2 / TiO2 / Ti is then pyrolyzed in a tube furnace at 400 °C for 1 h in an air atmosphere to finally obtain Co3O4 / TiO2 / Ti.

[0042] Step S5: Prepare a 0.1M sodium sulfide solution, place the electrode sheet obtained in step S4 at an angle in the 0.1M sodium sulfide solution, immerse it in a 60℃ water bath for 6 hours for sulfidation, then wash the sulfidated electrode sheet with deionized water and ethanol, dry it, and then heat treat it at 400℃ for 2 hours under an argon protective atmosphere to stabilize the sulfur vacancies, finally obtaining S-Co3O4 / TiO2 / Ti.

[0043] The catalytic cathode S-Co3O4 / TiO2 / Ti prepared in Example 1 above was used for the degradation of APAP, and the specific process is as follows:

[0044] Prepare 200 mL of a 100 mg / L acetaminophen solution and pour it into a single-chamber electrolytic reactor. Immerse the sulfur-doped cobalt tetroxide cathode (S-Co3O4 / TiO2 / Ti) and the graphite anode rod opposite each other in the solution. Connect a regulated DC power supply and set the current density to 30 mA / cm². 2 The reaction time was 120 min, and samples were taken at 0, 10, 20, 30, 60, 90, and 120 min. A 10 ml syringe with a 0.22 μm organic filter was used for sampling. The collected water samples were used to determine the CODcr and acetaminophen concentrations.

[0045] Example 2

[0046] In Example 2, the preparation method of Co(OH)2 / TiO2 / Ti material is the same as in Example 1, except that "in step S4, the electrodeposition time of the electrochemical workstation is 10, 20, 30, and 60 min respectively", and the other conditions remain unchanged. After electrodeposition, Co(OH)2 / TiO2 / Ti electrode sheet without pyrolysis treatment is obtained.

[0047] Photographs of Co(OH)2 / TiO2 / Ti electrodes prepared at different electrodeposition times using an electrochemical workstation, as shown in Example 2. Figure 1 As shown, Figure 1 The images from left to right correspond to electrode plates with electrodeposition times of 10, 20, 30, and 60 minutes. If the electrodeposition time is too short, the Co(OH)2 generated by electrodeposition cannot completely cover the substrate; if the time is too long, the Co(OH)2 film is prone to rupture.

[0048] Example 3

[0049] In Example 2, the preparation method of Co3O4 / TiO2 / Ti material was repeated in Example 1, except that "in step S4, the deposition voltages were -0.9, -1.1, and -1.3V respectively". All other conditions remained the same. After electrodeposition, the material was pyrolyzed at 400°C for 1 hour in an air atmosphere in a tube furnace to obtain Co3O4 / TiO2 / Ti materials.

[0050] Photographs of Co3O4 / TiO2 / Ti materials under different electrodeposition voltage conditions in Example 3 are shown below. Figure 2 As shown. Based on the test results, the optimal electrodeposition voltage can be determined to be -0.9V. When the voltage is increased to -1.1V and -1.3V, the electrodeposited Co(OH)2 film is prone to rupture and detachment due to the large amount of H2 generated on the Ti substrate, especially after calcination in a tube furnace, the detachment phenomenon is particularly obvious.

[0051] Example 4:

[0052] In Example 4, the preparation method of S-Co3O4 / TiO2 / Ti material is the same as in Example 1, except that the impregnation time of "step S5 sulfurization is 1, 2, 4, 6 and 8 hours respectively", and the other conditions remain unchanged.

[0053] FESEM images of the cathode materials S-Co3O4 / TiO2 / Ti prepared under sulfidation times of 1, 2, 4, 6, and 8 h in Example 4 are summarized in [the table below]. Figure 3 In, respectively as Figure 3 The sub-graphs a through e are shown below. Figure 3 As the sulfidation time increases, the "granular" morphology becomes more pronounced, gradually revealing a heterogeneous structure of lamellar and granular forms. After 6 hours of sulfidation, the lamellar Co3O4 gradually transforms into "Co3S" due to the introduction of sulfur vacancies. 4-x The formation of sulfides not only alters its morphology, making it spherical, but also increases the saturation of Co. 2+ / Co 3+ The proportion of "" enhanced the reducing ability. When the vulcanization time was increased to 8 hours, the spherical morphology became more obvious.

[0054] Example 5

[0055] The experimental steps of Example 5 are the same as those of Example 1, except that "the pyrolysis temperature of Co(OH)2 / TiO2 / Ti is changed to 300℃, 400℃ or 500℃ in step S4", while the other conditions remain unchanged.

[0056] The FESEM images of Co(OH)2 / TiO2 / Ti-x obtained by calcination at 300℃, 400℃ and 500℃ in step S4 of Example 3 are shown in Figure 1. Figure 4a , Figure 4b and Figure 4c As shown. From Figures 4a-4c It can be seen that Co3O4 at 300℃ has a thicker lamellar structure due to insufficient temperature. When the temperature is increased to 400℃, a more uniform porous structure and a thinner lamellar structure can be observed compared to 300℃. At 500℃, cracks were found on the surface of the lamellar structure, which may be due to excessively high temperature. Therefore, 400℃ was chosen as the optimal calcination temperature.

[0057] Comparative Example 1

[0058] The electrocatalytic degradation experiment of APAP was carried out according to the method described in Example 1, with the only difference being that "only the cathode material in the APAP degradation process was changed", while the other conditions remained the same.

[0059] The cathode materials used in Comparative Example 1 are the intermediate and final products in the cathode electrode preparation process of Example 1, namely, "pretreated Ti sheet, TiO2 / Ti, Co3O4 / TiO2 / Ti and S-Co3O4 / TiO2 / Ti".

[0060] Comparative Example 1: Electrocatalytic degradation results of APAP using different cathode materials are as follows Figure 5a and Figure 5b As shown, Figure 5a The removal rates of APAP after 120 min of electrocatalytic degradation were 23.78%, 37.14%, 57.71%, and 79.31%, respectively. Figure 5b The COD removal rates after 120 min of electrocatalytic degradation were 15.49%, 24.53%, 29.41%, and 41.57%, respectively. This indicates that S-Co3O4 / TiO2 / Ti exhibits the best catalytic activity for both APAP and COD removal.

[0061] Comparative Example 2

[0062] The preparation method of the cathode material in Comparative Example 2 is the same as that in Example 1, except that the impregnation and sulfidation time in step S5 is 1, 2, 4 and 6 h respectively. All other conditions remain unchanged, and the S-Co3O4 / TiO2 / Ti cathode material is finally obtained.

[0063] Comparative Example 2: The S-Co3O4 / TiO2 / Ti cathode materials prepared under different impregnation and sulfidation times were subjected to APAP electrocatalytic degradation experiments according to the method described in Example 1. The degradation results are as follows: Figure 6a and Figure 6b As shown.

[0064] APAP removal status as follows Figure 6a As shown, the electrocatalytic degradation removal rates of the S-Co3O4 / TiO2 / Ti cathode material at sulfidation times of 1, 2, 4, 6, and 8 h for 120 min were 52.21%, 31.81%, 24.77%, 79.31%, and 85.13%, respectively. The COD removal performance is as follows: Figure 6b As shown, the removal rates of S-Co3O4 / TiO2 / Ti cathode materials after 120 min of electrocatalytic degradation at sulfidation times of 1, 2, 4, 6, and 8 h were 29.31%, 19.87%, 12.54%, 41.57%, and 45.29%, respectively. With increasing sulfidation time, the removal rates of APAP and COD initially decreased and then increased. However, increasing the sulfidation time to 8 h only increased the APAP degradation rate by 5.82% and the COD removal rate by only 3.72% compared to a sulfidation time of 6 h. Therefore, 6 h of sulfidation was selected as the optimal sulfidation time.

[0065] Comparative Example 3

[0066] The electrocatalytic degradation experiment of APAP was carried out according to the method described in Example 1. The difference between Comparative Example 3 and Example 1 is that only the current density in the degradation of APAP and COD was changed, with the current density being 10, 20, 30, and 40 mA / cm². 2 The result is as follows Figure 7a and Figure 7b As shown. Among them, Figure 7a Regarding APAP removal, the removal rates after 120 minutes of electrocatalytic degradation were 20.37%, 79.31%, 51.37%, and 37.46%, respectively. Figure 7b Regarding COD removal, the removal rates after 120 min of electrocatalytic degradation were 13.44%, 41.57%, 37.44%, and 26.02%, respectively. With increasing current density, the removal rates of APAP and COD initially increased and then decreased; therefore, 20 mA / cm² was selected. 2 The optimal current density is determined by the increasing current density. As the current density increases, the number of generated electrons and active hydrogen gradually increases, leading to an increase in removal rate. However, the optimal current density is 30 mA / cm².2 At that time, the removal rate decreased due to the intensification of the hydrogen evolution reaction (HER).

[0067] Comparative Example 4

[0068] The electrocatalytic degradation experiment of APAP was carried out according to the method described in Example 1. The difference between Comparative Example 4 and Example 1 is that only the initial concentration of APAP was changed during the degradation process, which were 50, 100, 200, 400 and 500 mg / L respectively.

[0069] APAP removal status as follows Figure 8a As shown, the removal rates of APAP at concentrations of 50, 100, 200, 400, and 500 mg / L after 120 min of electrocatalytic degradation were 82.67%, 79.31%, 63.81%, 50.09%, and 38.47%, respectively. The COD removal rates are as follows: Figure 8b As shown, the removal rates of APAP at concentrations of 50, 100, 200, 400, and 500 mg / L after 120 min of electrocatalytic degradation were 46.29%, 44.57%, 35.01%, 27.52%, and 19.69%, respectively. The removal rates of both APAP and COD were highest when the initial APAP concentration was 50 mg / L. As the APAP concentration increased, the removal rates decreased. When the APAP concentration increased to 100 mg / L, the APAP removal rate decreased by 3.36%, and the COD removal rate decreased by 1.72%. Considering all factors, an initial concentration of 100 mg / L was selected as the optimal initial concentration.

Claims

1. The use of a cathode material in the electrocatalytic treatment of pharmaceutical and chemical wastewater, characterized in that The cathode material generates active hydrogen during electrolysis, and the active hydrogen and the electrons generated by electrolysis serve as active components for catalytic reduction and degradation of pharmaceutical and chemical wastewater. The method for preparing the cathode material includes the following steps: Step S1 Titanium sheet pretreatment: First, the titanium sheet is mechanically polished and acid-base cleaned, and then a clean and rough titanium substrate is prepared by ultrasonic-assisted chemical acid etching process. Step S2: Using the titanium substrate obtained in step S1 as the anode and the untreated titanium sheet as the cathode, immerse it in an electrolytic aqueous solution containing sodium fluoride and sodium bisulfate, and perform anodic oxidation corrosion treatment under electrolysis to form a titanium dioxide nanolayer on the titanium substrate. Then remove it, clean it, and let it air dry naturally. Step S3: The titanium material obtained in step S2 is heat-treated in an air atmosphere to obtain a titanium dioxide nano-transition layer electrode material with good thermal stability. Step S4: Using the titanium dioxide nano-transition layer electrode material obtained in step S3 as the working electrode, the inert conductive electrode as the counter electrode, and the saturated calomel electrode as the reference electrode, the working electrode and the counter electrode are separated by a proton exchange membrane. A Co(OH)2 layer is electrodeposited in an electrodeposition solution containing Co salt and sodium sulfate, and then heat-treated in an air atmosphere to obtain Co3O4 / TiO2-Ti. Step S5: The Co3O4 / TiO2-Ti prepared in step S4 is placed in a sodium sulfide solution and impregnated in a water bath. Then, it is heat-treated under an inert atmosphere to finally obtain the material S-Co3O4 / TiO2-Ti, which completes the preparation.

2. The application as described in claim 1, characterized in that... The specific process of step S1 is as follows: The titanium sheet is first polished with a grinding wheel and sandpaper, then cleaned with a 35-45% sodium hydroxide solution for 20-40 minutes, and then boiled in a 15-25% sulfuric acid solution for 30-50 minutes. Next, the titanium sheet is cleaned with ultrapure water, dried, and then immersed in a 10-20% oxalic acid solution. It is then placed in an ultrasonic cleaner and ultrasonically etched at a temperature of 20-40°C for 10-30 minutes.

3. The application as described in claim 1, characterized in that... In step S2, the sodium fluoride concentration in the electrolytic aqueous solution is 0.3~0.5 wt%, the sodium bisulfate concentration is 6~8 wt%, the anodic oxidation corrosion treatment temperature is 50-70℃, the treatment voltage is 20-40V, and the anodic oxidation time is 10-30min.

4. The application as described in claim 1, characterized in that... In step S3, the heat treatment temperature is 350-550℃ and the heat treatment time is 2-4 h.

5. The application as described in claim 4, characterized in that... In step S3, the heat treatment temperature is 400-450℃.

6. The method for preparing a cathode material for pharmaceutical and chemical wastewater treatment based on active hydrogen regulation as described in claim 1, characterized in that... In step S4, the concentration of Co in the electrodeposition solution is 0.05~0.2 M, the concentration of sodium sulfate is 0.05~0.2 M, the electrodeposition voltage is -0.9 ~ -1.3 V, and the electrodeposition time is 10~60 min.

7. The application as described in claim 6, characterized in that... In step S4, the electrodeposition time is 30~40 min.

8. The application as described in claim 1, characterized in that... In step S4, the heat treatment temperature is 300~500℃ and the heat treatment time is 0.5-2h.

9. The application as described in claim 8, characterized in that... In step S4, the heat treatment temperature is 400±50℃.

10. The application as described in claim 1, characterized in that... In step S5, the concentration of the sodium sulfide solution is 0.05-0.2M, the immersion temperature is 50-70℃, and the immersion time is 1-6h; the heat treatment temperature in step S5 is 350-450℃, and the heat treatment time is 1-4h.

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