Preparation method and use method of metal sulfide

Abstract

The invention provides a preparation method and a use method of metal sulfide.The preparation method comprises the steps that S1, copper sulfate pentahydrate and sodium tungstate dihydrate are dissolved in a beaker containing 50 mL of ultrapure water, a mixed solution is obtained, then thiourea is added into the mixed solution, stirring is conducted for 30 min, and turbid liquid is formed; s2, pouring the turbid liquid into a 150mL reaction kettle, pouring 50mL of ultrapure water into the reaction kettle, uniformly stirring, and then putting the reaction kettle into an oven for high-temperature reaction to obtain a final turbid liquid; and S3, after the reaction kettle is cooled, taking out the reaction kettle, washing and filtering the final turbid liquid in the reaction kettle for multiple times by using absolute ethyl alcohol and ultrapure water, and carrying out vacuum drying treatment on the obtained precipitate to obtain the double-center binary metal sulfide CuS / WO3. The embodiment of the invention provides the preparation method of the metal sulfide, and tetracycline pollutants in water can be effectively removed.

Description

Technical Field

[0001] The present invention relates to the technical field of metal sulfide material preparation, and in particular to a preparation method and a use method of metal sulfide. Background Art

[0002] Tetracycline (TC) is a broad-spectrum antibiotic and the second most widely used antibiotic. It is frequently used in humans and animals to treat bacterial diseases. However, only 10% to 20% of the tetracycline ingested by humans or animals is absorbed by the organism. The remainder is excreted in feces and urine as the parent compound or metabolites. Urban sewage treatment plants are inefficient at treating antibiotics, ultimately leading to the release of tetracycline and other antibiotics into the aquatic environment. The widespread use of tetracycline antibiotics leads to the persistent presence of tetracycline residues in the aquatic environment. These residues enter the human body through the food chain, drinking water, and other channels, disrupting endocrine function and promoting antibiotic resistance.

[0003] Advanced oxidation, especially catalytic advanced oxidation (CAOPs), is a highly effective solution with advantages such as high treatment efficiency, short residence time and simple equipment requirements. CAOPs activated by potassium peroxydisulfate have attracted much attention due to their attractive properties. Compared with systems based on hydroxyl (·OH) radicals, CAOPs based on sulfate radicals (SO4·-) (CAOPs-SR) have obvious advantages, including higher oxidation potential and longer half-life, making them more efficient in removing pollutants. Specifically, CAOPs-SR has a wider pH adaptability (2.0-10.0) and is cost-effective, stable, and easy to store and transport, making it highly regarded.

[0004] Potassium peroxydisulfate (PMS) has a molecular formula of KHSO5 and is a white solid powder. Its stability is highest when pH < 6 or pH = 12, and its stability is lowest when pH = 9. PMS has a solubility greater than 250g / L in water and has an asymmetric structure with an OO bond length of The bond energy is 140~213kJ / mol.

[0005] Adding potassium peroxydisulfate to wastewater containing trace amounts of tetracycline does not effectively degrade tetracycline. Adding metal sulfide CuS / WO3 together with potassium peroxydisulfate catalyzes the oxidation of the potassium peroxydisulfate, producing a large amount of active substances that greatly improve the degradation rate of tetracycline.

[0006] Therefore, there is an urgent need for a preparation method of double-center metal sulfide CuS / WO3. Summary of the Invention

[0007] The present invention provides a method for preparing metal sulfide, and its main purpose is to provide a method for preparing metal sulfide, which can effectively remove tetracycline pollutants in water.

[0008] In a first aspect, an embodiment of the present invention provides a method for preparing a metal sulfide, comprising:

[0009] S1, dissolving copper sulfate pentahydrate and sodium tungstate dihydrate in a beaker containing 50 mL of ultrapure water to obtain a mixed solution, and then adding thiourea to the mixed solution and stirring for 30 minutes to form a suspension;

[0010] S2, pouring the suspension into a 150 mL reactor, pouring 50 mL of ultrapure water into the reactor and stirring evenly, and then placing the reactor in an oven for high-temperature reaction to obtain a final suspension;

[0011] S3, after the reactor is cooled, it is taken out, the final suspension in the reactor is washed and filtered multiple times with anhydrous ethanol and ultrapure water, and the obtained precipitate is vacuum dried to obtain a dual-center binary metal sulfide CuS / WO3.

[0012] Furthermore, in step S1, the specific method of adding thiourea to the mixed solution is:

[0013] The solid particles of thiourea are added into the mixed solution under stirring three times.

[0014] Furthermore, in step S1, the molar ratio of the copper sulfate pentahydrate, the sodium tungstate dihydrate and the thiourea is 3:3:2.5.

[0015] Furthermore, the weight of the copper sulfate pentahydrate is 0.75 g, the weight of the sodium tungstate dihydrate is 0.99 g, and the weight of the thiourea is 0.19 g.

[0016] Furthermore, in step S2, the final suspension is 100 mL, and the stirring time ranges from 10 min to 40 min.

[0017] Furthermore, in step S2, the temperature of the high temperature reaction is 180° C., and the reaction time is 24 hours.

[0018] Furthermore, in step S3, the washing and filtering process is specifically as follows:

[0019] The final suspension in the reactor is treated until the filtered wastewater is colorless.

[0020] Furthermore, in step S3, the vacuum drying process is specifically as follows:

[0021] The precipitate was dried in a vacuum drying oven at 60° C. for 3 to 7 hours.

[0022] Furthermore, after drying the precipitate in a vacuum drying oven at 60° C. for 3 to 7 hours, the method further comprises:

[0023] The dried precipitate is ground to make the particle size of the binocular binary metal sulfide less than 0.35 mm.

[0024] In a second aspect, an embodiment of the present invention provides an application method of metal sulfide, comprising:

[0025] Potassium peroxodisulfate and the double-center binary metal sulfide CuS / WO3 obtained by the preparation method of metal sulfide provided by the first aspect are added to sewage containing tetracycline, and the potassium peroxodisulfate is catalytically oxidized to degrade the tetracycline in the sewage.

[0026] This invention proposes a method for preparing and using metal sulfides. Using a dual-center binary metal sulfide (CuS / WO3) as a catalyst and potassium persulfate as an oxidant, these two components together form a catalytic advanced oxidation technology. The copper tungsten sulfide effectively activates the oxidant to produce highly oxidizing free radicals, effectively removing tetracycline contaminants from water. This catalytic advanced oxidation technology, as described in this invention, is used in water treatment applications involving tetracycline contaminants, such as wastewater and drinking water treatment, effectively degrading them. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A flow chart of a method for preparing metal sulfide provided in an embodiment of the present invention;

[0028] Figure 2 XRD spectrum of the dual-center binary metal sulfide CuS / WO3 catalyst prepared in an embodiment of the present invention;

[0029] Figure 3 This is a SEM image of the dual-center binary metal sulfide CuS / WO3 catalyst prepared in an embodiment of the present invention;

[0030] Figure 4 Graphs showing the effects of tetracycline degradation by a dual-center binary metal sulfide CuS / WO3 activated potassium peroxodisulfate system prepared in an embodiment of the present invention, a separately prepared dual-center binary metal sulfide CuS / WO3 system, and a separate potassium peroxodisulfate system;

[0031] Figure 5 Graph showing the PMS utilization rate for tetracycline degradation using a dual-center binary metal sulfide CuS / WO3 activated potassium peroxodisulfate system prepared in accordance with an embodiment of the present invention, a separately prepared dual-center binary metal sulfide CuS / WO3 system, and a separate potassium peroxodisulfate system;

[0032] Figure 6 This is a diagram showing the effect of the dual-center binary metal sulfide CuS / WO3 activated potassium peroxodisulfate system prepared in the example on the degradation of tetracycline in lake water and tap water;

[0033] Figure 7 This is a graph showing the stability of the CuS / WO3 system activated with potassium peroxodisulfate prepared in Example 1 after five cycles of use in lake water and tap water;

[0034] Figure 8 This is a diagram showing the effect of the double-center binary metal sulfide CuS / WO3 prepared in an embodiment of the present invention on the degradation of tetracycline in the presence of different inorganic anions;

[0035] Figure 9 This is a diagram showing the effect of the double-center binary metal sulfide CuS / WO3 prepared in an embodiment of the present invention on the degradation of tetracycline under the influence of different humic acids;

[0036] Figure 10 This is an EPR graph of a highly oxidizing free radical generated by the potassium peroxodisulfate system activated by the dual-center binary metal sulfide CuS / WO3 prepared in an embodiment of the present invention;

[0037] Figure 11 This is another EPR graph of highly oxidizing free radicals generated by the potassium peroxodisulfate system activated by the double-center binary metal sulfide CuS / WO3 prepared in an embodiment of the present invention.

[0038] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0039] The embodiments of the present application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0040] In order to enable those skilled in the art to better understand the solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0041] In the embodiments of the present application, at least one refers to one or more; a plurality refers to two or more. In the description of the present application, words such as "first", "second", and "third" are only used for the purpose of distinguishing descriptions, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying order. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0042] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, the terms "including," "comprising," "having," and their variations in this specification all mean "including but not limited to," unless otherwise specifically stated.

[0043] Figure 1 A flow chart of a method for preparing metal sulfide provided in an embodiment of the present invention is as follows: Figure 1 As shown, the method includes:

[0044] S1, dissolving copper sulfate pentahydrate and sodium tungstate dihydrate in a beaker containing 50 mL of ultrapure water to obtain a mixed solution, and then adding thiourea to the mixed solution and stirring for 30 minutes to form a suspension;

[0045] Wherein, in the step S1, the specific method of adding thiourea to the mixed solution is: adding the solid particles of thiourea to the mixed solution in a stirred state three times.

[0046] Wherein, in the step S1, the molar ratio of the copper sulfate pentahydrate, the sodium tungstate dihydrate and the thiourea is 3:3:2.5.

[0047] Experiments have shown that under this ratio setting, the catalytic performance is the strongest, thereby reducing the reaction time.

[0048] As an example, the weight of the copper sulfate pentahydrate is 0.75 g, the weight of the sodium tungstate dihydrate is 0.99 g, and the weight of the thiourea is 0.19 g.

[0049] S2, pouring the suspension into a 150 mL reactor, pouring 50 mL of ultrapure water into the reactor and stirring evenly, and then placing the reactor in an oven for high-temperature reaction to obtain a final suspension;

[0050] Wherein, in step S2, the final suspension is 100 mL, and the stirring time ranges from 10 min to 40 min. As an example, the stirring time can be 10 min, 12 min, 20 min, 25 min, 30 min, 35 min, and 40 min, with the minimum stirring time being 10 min and the optimal time being 30 min.

[0051] Wherein, in the step S2, the temperature of the high temperature reaction is 180° C., and the reaction time is 24 hours.

[0052] S3, after the reactor is cooled, it is taken out, the final suspension in the reactor is washed and filtered multiple times with anhydrous ethanol and ultrapure water, and the obtained precipitate is vacuum dried to obtain a dual-center binary metal sulfide CuS / WO3.

[0053] Wherein, in the step S3, the washing and filtering treatment specifically comprises: treating the final suspension in the reactor until the filtered wastewater is colorless.

[0054] In step S3, the vacuum drying treatment specifically includes drying the precipitate in a vacuum drying oven at 60°C for 3 to 7 hours. As an example, the drying time of the precipitate in the vacuum drying oven can be 3 hours, 3.2 hours, 3.5 hours, 4 hours, 4.6 hours, 5 hours, 5.2 hours, 5.8 hours, 6 hours, 6.5 hours, and 7 hours. The drying time is at least 3 hours, and the optimal drying time is 6 hours.

[0055] Wherein, after drying the precipitate in a vacuum drying oven at 60° C. for 3 to 7 hours, the method further comprises:

[0056] The dried precipitate is ground to make the particle size of the binocular binary metal sulfide less than 0.35 mm.

[0057] An embodiment of the present invention further provides an application method of metal sulfide, comprising:

[0058] Potassium peroxodisulfate and the double-center binary metal sulfide CuS / WO3 obtained by the above-mentioned metal sulfide preparation method are added to sewage containing tetracycline, and the potassium peroxodisulfate is catalytically oxidized to degrade the tetracycline in the sewage.

[0059] In one embodiment, in order to study the effect of dual-center binary metal sulfide CuS / WO3 activated potassium persulfate on the degradation of tetracycline, tetracycline was selected as the target pollutant in this embodiment. The dual-center binary metal sulfide CuS / WO3 activated potassium persulfate system prepared in the embodiment, the dual-center binary metal sulfide CuS / WO3 system prepared separately, and the potassium persulfate system alone were used to degrade tetracycline. The experimental results are shown in FIG. Figure 2 and Figure 3 shown. Figure 2 This is the XRD spectrum of the dual-center binary metal sulfide CuS / WO3 catalyst prepared in an embodiment of the present invention. The full name of the XRD spectrum is X-Ray Diffraction spectrum, that is, the X-ray diffraction spectrum. The curve corresponding to CuS / WO3 in the figure represents the dual-center binary metal sulfide CuS / WO3 activated potassium persulfate system. The curve corresponding to CuS in the figure represents the XRD spectrum of CuS. The curve corresponding to CuS PDF#04-007-1392 represents the CuS standard PDF card, and the standard PDF card is a standard diffraction card. The curve corresponding to WO3 PDF#04-007-2322 represents the WO3 standard PDF card. Figure 2 The horizontal axis represents the diffraction angle, and the vertical axis represents the diffraction intensity; Figure 3 This is an SEM image of the dual-center binary metal sulfide CuS / WO3 catalyst prepared in accordance with an embodiment of the present invention, wherein the full name of the SEM image is Scanning Electron Microscope, i.e., a scanning electron microscope image. In the image, 100 nm represents the surface scanning electron microscope image of CuS / WO3 after magnification, and 1 um represents the surface scanning electron microscope image of CuS / WO3 under a wider range. In the image, Cu represents the EDS energy spectrum of the Cu element, W represents the EDS energy spectrum of the W element, and S represents the EDS energy spectrum of the S element. The EDS energy spectrum can clearly show the distribution of Cu, W, and S elements in CuS / WO3. The tetracycline concentration is 15 mg / L, the dosage of the dual-center binary metal sulfide CuS / WO3 is 40 mg / L, and the dosage of potassium peroxydisulfate is 2 mM.

[0060] Degradation experiments were conducted in 100mL beakers for all three systems, maintaining the following parameters: a tetracycline concentration of 15mg / L, a dual-center binary metal sulfide dosage of 40mg / L, and a potassium peroxydisulfate dosage of 2mM. Reactions were maintained in a constant-temperature magnetic stirring water bath at 25°C and 500rpm. 1mL samples were withdrawn from the suspension in the beakers using a syringe at time points of 0, 6, 12, 18, 24, and 30 minutes. After filtering through a 0.22μm polytetrafluoroethylene (PTFE) membrane, the tetracycline absorbance was measured at a wavelength of 356nm using a UV-visible spectrophotometer to analyze the tetracycline concentration.

[0061] Figure 4The figures show the effects of tetracycline degradation by the dual-center binary metal sulfide CuS / WO3 activated potassium peroxydisulfate system prepared in accordance with an embodiment of the present invention, a separately prepared dual-center binary metal sulfide CuS / WO3 system, and a separate potassium peroxydisulfate system. In the figure, the curve corresponding to CuS / WO3Alone represents the degradation rate of tetracycline when only the dual-center binary metal sulfide CuS / WO3 is added, the curve corresponding to PMSAlone represents the separate potassium peroxydisulfate system, the curve corresponding to WS2+PMS represents the WS2-activated potassium peroxydisulfate system, the curve corresponding to CuS+PMS represents the CuS-activated potassium peroxydisulfate system, the curve corresponding to CuWO4+PMS represents the CuWO4-activated potassium peroxydisulfate system, and the curve corresponding to CuS / WO3+PMS represents the CuS / WO3-activated potassium peroxydisulfate system. The abscissa represents the reaction time, and the ordinate represents the degradation rate of tetracycline. Figure 5 This is a graph of the PMS utilization for the degradation of tetracycline by the dual-center binary metal sulfide CuS / WO3 activated potassium peroxydisulfate system prepared in an embodiment of the present invention, a separately prepared dual-center binary metal sulfide CuS / WO3 system, and a separate potassium peroxydisulfate system. In the graph, the curve corresponding to Olny PMS represents the separate potassium peroxydisulfate system, the curve corresponding to WS2+PMS represents the WS2 activated potassium peroxydisulfate system, the curve corresponding to CuS+PMS represents the CuS activated potassium peroxydisulfate system, the curve corresponding to CuWO4+PMS represents the CuWO4 activated potassium peroxydisulfate system, and the curve corresponding to CuS / WO3+PMS represents the CuS / WO3 activated potassium peroxydisulfate system. The horizontal axis represents the reaction time, and the vertical axis represents the potassium peroxydisulfate utilization.

[0062] Depend on Figure 4 and Figure 5 As can be seen, the dual-center binary metal sulfide CuS / WO3-activated potassium peroxodisulfate system significantly outperformed the other systems in degrading tetracycline, achieving over 95% degradation in 30 minutes. In contrast, the dual-center binary metal sulfide system alone degraded 50.3% of tetracycline, while the potassium peroxodisulfate system alone degraded 60.3%.

[0063] In another example, to study the effect of potassium persulfate activated by CuS / WO3 on the degradation of tetracycline, tetracycline was selected as the target pollutant in this example. The potassium persulfate system activated by CuS / WO3 was used to degrade tetracycline in ultrapure water, lake water, and tap water, respectively. Figure 6This is a diagram showing the effect of the dual-center binary metal sulfide CuS / WO3 activated potassium peroxodisulfate system prepared in an embodiment of the present invention on the degradation of tetracycline in lake water and tap water. In the figure, Lake water represents lake water, Tap water represents tap water, and Ulterpure water represents ultrapure water. The horizontal axis represents the reaction time, and the vertical axis represents the tetracycline degradation rate. Figure 6 The bar graph in the upper right corner shows the first-order kinetic constants of tetracycline degradation in different water systems, and the vertical axis shows the magnitude of the first-order kinetic constants; Figure 7 This is a stability diagram of the CuS / WO3 system activated with potassium peroxodisulfate (KPS) activated by a dual-center binary metal sulfide CuS / WO3 system prepared in an embodiment of the present invention after five cycles of use in lake water and tap water. In the figure, 1st represents one cycle, 2nd represents two cycles, 3rd represents three cycles, 4th represents four cycles, and 5th represents five cycles. The horizontal axis represents reaction time, and the vertical axis represents tetracycline degradation rate.

[0064] The experimental results are as follows Figure 6 and Figure 7 As shown in the figure, lake water was collected from Huangjia Lake in Wuhan, and tap water was collected from Laboratory 314 in the experimental building of Wuhan Technology and Business University. The tetracycline concentration was 15 mg / L, the double-center binary metal sulfide CuS / WO3 was added at a dosage of 40 mg / L, and the potassium persulfate dosage was 2 mM.

[0065] Degradation experiments were conducted in 100mL beakers for all three systems, maintaining the following parameters: a tetracycline concentration of 15mg / L, a 40mg / L dosage of the dual-center binary metal sulfide CuS / WO3, and a 2mM dosage of potassium peroxydisulfate. Reactions were maintained in a constant-temperature magnetic stirring water bath at 25°C and 500rpm. 1mL samples were withdrawn from the suspension in the beakers using a syringe at time points of 0, 6, 12, 18, 24, and 30 minutes. After filtering through a 0.22μm polytetrafluoroethylene membrane, the tetracycline absorbance was measured at a wavelength of 356nm using a UV-visible spectrophotometer to analyze the tetracycline concentration.

[0066] Figure 8 This is a diagram showing the effect of the double-center binary metal sulfide CuS / WO3 prepared in the embodiment of the present invention on the degradation of tetracycline in the presence of different inorganic anions. In the figure, NoAnion represents a system without the addition of anions, and 5mM CI - Indicates the addition of 5mM CI - Ionic system, 5mM Indicates the addition of 5mM Ionic system, 5mM Indicates the addition of 5mM Ionic system, 5mM Indicates the addition of 5mM Ionic system, 5mM Indicates the addition of 5mM Ionic system, 5mMCH3COO - Indicates the addition of 5mM CH3COO - Ionic system, 5mM Indicates the addition of 5mM ion system, the horizontal axis represents the reaction time, and the vertical axis represents the degradation rate of tetracycline. Figure 9 This is a diagram showing the effect of tetracycline degradation by the dual-center binary metal sulfide CuS / WO3 prepared in an embodiment of the present invention under the influence of different humic acids. In the figure, 50 mg / L represents a system with 50 mg / L humic acid added, 20 mg / L represents a system with 20 mg / L humic acid added, 10 mg / L represents a system with 10 mg / L humic acid added, 5 mg / L represents a system with 5 mg / L humic acid added, and NO HA represents a system without humic acid added. Figure 9 The vertical axis of the bar graph in the upper right corner represents the first-order kinetic constant.

[0067] Depend on Figure 8 and Figure 9 It can be seen that the double-center binary metal sulfide CuS / WO3 prepared in the example has good tetracycline degradation performance in ultrapure water, and the degradation performance is only slightly affected in tap water containing impurities and in complex lake water.

[0068] Performance testing:

[0069] (1) The above two examples can be used as performance tests for the dual-center binary metal sulfide CuS / WO3 catalyst prepared in the examples.

[0070] (2) XRD test: XRD test was performed on the double-center binary metal sulfide CuS / WO3 prepared in the embodiment. As a control group, XRD test was also performed on WO3 and CuS. Figure 2 and Figure 3 shown.

[0071] (3) Electron Paramagnetic Resonance (EPR) test: EPR was used to verify the active free radicals in the dual-center binary metal sulfide CuS / WO3 activated potassium peroxydisulfate system. DMPO was used as a scavenger for ·OH and SO4·-. DMPO can react with ·OH and SO4·- to generate relatively stable DMPO-·OH and Addition products, using the hyperfine splitting constants of addition products, EPR can identify specific signal peaks, such as Figure 10 and Figure 11As shown in the figure, four signals with an apparent intensity ratio of 1:2:2:1 are formed, representing the presence of DMPO-·OH, i.e., the presence of system ·OH. The six signals around DMPO-·OH are Proof System The presence of TEMP as 1 Spin trapping agent for O2-active species, TEMP trapping 1 O2 produces a typical and strong 1:1:1 signal, proving that the system contains 1 O2, Figure 10 This is an EPR graph of a highly oxidizing free radical generated by the potassium peroxodisulfate system activated by the dual-center binary metal sulfide CuS / WO3 prepared in an embodiment of the present invention. In the figure, DMPO-·OH represents the signal curve generated by capturing ·OH. Indicates capture The generated signal curve has the horizontal axis representing the magnetic field and the vertical axis representing the signal strength; Figure 11 This is another EPR diagram of highly oxidizing free radicals generated by the double-center binary metal sulfide CuS / WO3 activated potassium peroxydisulfate system prepared in an embodiment of the present invention. In the figure, TEMP- 1 O2 means capture 1 The signal curve generated by O2, the horizontal axis represents the magnetic field, and the vertical axis represents the signal intensity, such as Figure 10 and Figure 11 shown.

[0072] In the present invention, the term "Example" refers to a dual-center binary metal sulfide CuS / WO3 catalyst prepared according to the steps of the present invention, or to an experiment using the dual-center binary metal sulfide CuS / WO3 catalyst prepared in the Example. Those skilled in the art may expand upon the Examples or illustrations and their features described in this specification unless otherwise specified.

[0073] Those skilled in the art will clearly understand that for the sake of convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0074] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. A method for preparing metal sulfide, characterized in that: include: S1, dissolving copper sulfate pentahydrate and sodium tungstate dihydrate in a beaker containing 50 mL of ultrapure water to obtain a mixed solution, and then adding thiourea to the mixed solution and stirring for 30 minutes to form a suspension; S2, pouring the suspension into a 150 mL reactor, pouring 50 mL of ultrapure water into the reactor and stirring evenly, and then placing the reactor in an oven for high-temperature reaction to obtain a final suspension; S3, after the reactor is cooled, it is taken out, the final suspension in the reactor is washed and filtered multiple times with anhydrous ethanol and ultrapure water, and the obtained precipitate is vacuum dried to obtain a dual-center binary metal sulfide CuS / WO3.

2. The method for preparing metal sulfide according to claim 1, characterized in that: In step S1, the specific method of adding thiourea to the mixed solution is: The solid particles of thiourea are added into the mixed solution under stirring three times.

3. The method for preparing metal sulfide according to claim 1, characterized in that: In the step S1, the molar ratio of the copper sulfate pentahydrate, the sodium tungstate dihydrate, and the thiourea is 3:3:2.

5.

4. The method for preparing metal sulfide according to claim 3, characterized in that: The weight of the copper sulfate pentahydrate is 0.75 g, the weight of the sodium tungstate dihydrate is 0.99 g, and the weight of the thiourea is 0.19 g.

5. The method for preparing metal sulfide according to claim 1, characterized in that: In step S2, the final suspension is 100 mL, and the stirring time ranges from 10 min to 40 min.

6. The method for preparing metal sulfide according to claim 1, characterized in that: In step S2, the temperature of the high temperature reaction is 180° C. and the reaction time is 24 hours.

7. The method for preparing metal sulfide according to claim 1, characterized in that: In step S3, the washing and filtering process is specifically as follows: The final suspension in the reactor is treated until the filtered wastewater is colorless.

8. The method for preparing metal sulfide according to claim 1, characterized in that: In step S3, the vacuum drying process is specifically as follows: The precipitate was dried in a vacuum drying oven at 60° C. for 3 to 7 hours.

9. The method for preparing metal sulfide according to claim 8, characterized in that: After drying the precipitate in a vacuum drying oven at 60° C. for 3 to 7 hours, the method further comprises: The dried precipitate is ground to make the particle size of the binocular binary metal sulfide less than 0.35 mm.

10. A method for applying metal sulfide, characterized in that: include: Potassium peroxydisulfate and a double-center binary metal sulfide CuS / WO3 obtained by the method for preparing metal sulfides according to any one of claims 1 to 8 are added to sewage containing tetracycline, and the potassium peroxydisulfate is catalytically oxidized to degrade the tetracycline in the sewage.

Images