Application of Molybdenum Trisulfide Catalyst in Catalytic Removal of Carbamazepine

Abstract

The present invention relates to the field of environmental pollution control, and discloses the application of a molybdenum trisulfide catalyst in the piezoelectric catalytic removal of carbamazepine, wherein the molybdenum trisulfide catalyst is obtained by stirring a mixed solution of molybdenum trioxide, a sulfide salt and water at a high speed and slowly adding acid until a large amount of gaseous hydrogen sulfide is produced, and drying to obtain a black solid. The molybdenum trisulfide catalyst is used to self-supply hydrogen peroxide under piezoelectric conditions and activate hydrogen peroxide to produce active substances, which can greatly improve the efficiency of removing carbamazepine in water bodies, and the removal rate can be as high as 99.3%, and the toxicity is reduced in the process of removing carbamazepine. In addition, the catalyst of the present invention can be recycled and easily recovered after the reaction, and will not cause pollution to the water environment.

Description

Technical Field

[0001] The invention relates to the field of environmental pollution control, and in particular to the application of a molybdenum trisulfide catalyst in piezoelectric catalytic removal of carbamazepine. Background Art

[0002] Carbamazepine (CBZ) is a common psychotropic drug with anti-epileptic effects similar to phenytoin sodium and is widely used in clinical practice. A large amount of discarded carbamazepine drugs enter the water environment directly or indirectly as solid waste, posing a huge threat to the management of the water environment. Therefore, it is necessary to seek economical and effective methods to completely degrade carbamazepine in water bodies.

[0003] Chinese patent publication number CN 117531529 A discloses a ruthenium-doped hollow tubular molybdenum disulfide catalytic material and its preparation method, wherein the catalytic material uses a hollow tubular molybdenum disulfide as a carrier, and the hollow tubular molybdenum disulfide is formed by stacking and enclosing a large number of molybdenum disulfide nanosheets, and the metal Ru is fixed on the carrier. The catalyst not only needs to add the precious metal ruthenium, but also has a complicated preparation process; in addition, the catalyst is used as an activator of PMS to produce active oxidative species (ROSs) to degrade organic pollutants in aqueous solution. Therefore, PMS is also added as an oxidant when degrading carbamazepine. The production cost of this method is high and it is difficult to apply on a large scale.

[0004] Piezoelectric catalytic technology is a technology that directly converts mechanical energy into chemical energy through the piezoelectric effect of piezoelectric catalysts, thereby achieving the degradation of organic pollutants. Deformation is a necessary condition for inducing the piezoelectric effect of piezoelectric catalysts. The most common external stimulus sources are ultrasound, mechanical stress, biomechanical energy, water flow, wind, etc. Under the action of the ultrasonic field, the bubbles diffuse and rupture due to ultrasonic vibration, generating very high local pressure (10 8 Pa), piezoelectric catalysts are prone to mechanical bending under local high pressure, resulting in changes in polarization field strength and piezoelectric potential. When the frequency of ultrasonic vibration is close to the natural frequency of the piezoelectric material, the piezoelectric material produces the maximum deformation. In order to obtain efficient piezoelectric driving force in wastewater treatment and energy recovery, a high-frequency ultrasonic cleaning machine is usually used to drive the reaction. Ultrasound is the most commonly used method for deforming piezoelectric catalysts. A Chinese patent with publication number CN 112892550 A discloses a lanthanum-manganese dual-doped bismuth ferrite nanomaterial and its preparation method and application. The method uses piezoelectric catalytic technology to degrade carbamazepine, but the method requires high-temperature calcination (calcination at 550°C for 2h), which consumes a lot of energy, and its degradation efficiency can only reach 90% at most, and the degradation efficiency still needs to be improved.

[0005] At present, research on molybdenum trisulfide mainly focuses on the field of lithium batteries, and there has been no research in the field of piezoelectric catalytic degradation of organic pollutants. Summary of the invention

[0006] In order to overcome the above-mentioned shortcomings and deficiencies of the existing piezoelectric catalytic technology, the purpose of the present invention is to utilize the unique properties of molybdenum trisulfide catalyst in combination with piezoelectricity for application.

[0007] The technical solution of the present invention is as follows:

[0008] The invention discloses an application of a molybdenum trisulfide catalyst in removing carbamazepine. The molybdenum trisulfide catalyst is prepared by stirring a mixture of molybdenum trioxide, a sulfide salt and water at a high speed while slowly adding acid until a large amount of gaseous hydrogen sulfide is generated, and then drying to obtain a black solid.

[0009] Preferably, the above application comprises the following steps:

[0010] (1) adding a molybdenum trisulfide catalyst to the water to be treated containing carbamazepine and stirring; the concentration of the molybdenum trisulfide catalyst in the water is 0.25-2 g / L;

[0011] (2) The water to be treated obtained in step (1) is subjected to ultrasonic treatment; the power of the ultrasonic treatment is greater than 80 W and the time is greater than 30 min.

[0012] Preferably, the concentration of the molybdenum trisulfide catalyst in water is 1.0±0.5 g / L.

[0013] Preferably, the power of the ultrasonic treatment is 100±10 W, and the time is 40±5 min.

[0014] Preferably, the preparation of the molybdenum trisulfide catalyst comprises the following steps:

[0015] (1) Add molybdenum trioxide to the sulfide salt solution, stir at a high speed of more than 1000 rpm, and slowly add acid solution until the pH value of the solution drops to 4±0.5;

[0016] (2) The above solution is boiled to remove hydrogen sulfide in the solution; after cooling, washing and drying, a black solid is obtained, which is ground into powder to obtain a molybdenum trisulfide catalyst.

[0017] Preferably, the molar ratio of the molybdenum trioxide to the sulfide salt is 1:(3-7); more preferably, the molar ratio of the molybdenum trioxide to the sulfide salt is 1:5.

[0018] Preferably, the concentration of the sulfide salt aqueous solution is 0.05-0.30 mol / L; more preferably, the concentration of the sulfide salt aqueous solution is 0.1-0.2 mol / L.

[0019] Preferably, the sulfide salt is sodium sulfide or potassium sulfide; and the acidic solution is an aqueous hydrochloric acid solution and / or an aqueous sulfuric acid solution.

[0020] Preferably, the high-speed stirring speed is 1000-4000 rpm, the high-speed stirring time is the time used to adjust the pH value to 4±0.5; the boiling time is 30±10 minutes; the drying temperature is 80±20°C; the drying time is 8-16 hours. The reaction temperature is the temperature when the solution is boiled; the reaction time is the time to completely remove hydrogen sulfide.

[0021] The present invention is directed to the preparation of molybdenum trisulfide, and utilizes its piezoelectric properties and common piezoelectric catalysis to effectively separate the electrons and holes generated by piezoelectricity under ultrasonic conditions to directly or indirectly reduce and remove carbamazepine in the environment.

[0022] The molybdenum trisulfide catalyst of the present invention has a disordered molecular chain structure and has unique structural / physical advantages, including amorphous, high sulfur concentration and good electrical conductivity. The amorphous structure of molybdenum trisulfide contains abundant unsaturated coordination and surface exposed defects, which provide a large number of active centers for the generation and activation of active substances; the high sulfur concentration of molybdenum trisulfide is conducive to the generation of more sulfur vacancies, which helps to effectively adsorb / activate active species; molybdenum trisulfide has a higher electrical conductivity because it has a smaller band gap, which is also conducive to the generation and activation of active species, which accelerates the efficiency of electron transfer. The present invention utilizes the above-mentioned properties of the molybdenum trisulfide catalyst, and the built-in electric field formed by piezoelectric polarization can promote the separation of electron-hole pairs, and self-supply hydrogen peroxide and activate hydrogen peroxide to produce active substances during the piezoelectric catalysis process to remove carbamazepine.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0024] The molybdenum trisulfide catalyst prepared by the present invention has obvious piezoelectric catalytic performance, good stability and excellent catalytic performance. In the piezoelectric catalytic process, it can self-supply hydrogen peroxide and activate hydrogen peroxide to produce active substances, thereby improving the efficiency of removing carbamazepine in water. In addition, the catalyst of the present invention is simple to prepare, low in cost, and can be recycled and easily recovered after the reaction, and will not cause pollution to the water environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a characterization diagram of molybdenum trisulfide prepared in Example 1 of the present invention, wherein Figure 1 A is the SEM image (scanning electron microscope image), Figure 1 B is a TEM image (transmission electron microscope image), Figure 1 C is the XRD pattern (X-ray diffraction spectrum), Figure 1 D is the XPS diagram (X-ray electron spectrum diagram) for analyzing the coordination structure of molybdenum element. Figure 1 E is the XPS diagram (X-ray electron spectrum) for analyzing the coordination structure of sulfur element.

[0026] Figure 2 This is a diagram showing the effect of different concentrations of molybdenum trisulfide catalysts in Example 2 of the present invention on removing carbamazepine.

[0027] Figure 3 This is a diagram showing the effect of removing carbamazepine under different ultrasonic power conditions in Example 3 of the present invention.

[0028] Figure 4 This is a diagram showing the effect of removing carbamazepine under optimal conditions in Example 4 of the present invention.

[0029] Figure 5 This is a diagram showing the effect of piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst under different pH conditions in Example 5 of the present invention.

[0030] Figure 6 This is a diagram showing the effect of piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst in real water in Example 6 of the present invention.

[0031] Figure 7 This is a test diagram of the cycle performance of piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst in Example 7 of the present invention.

[0032] Figure 8 This is a diagram showing the effect of piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst in Example 8 of the present invention. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0034] Unless otherwise specified, all reagents used in the examples can be purchased from the market. Molybdenum trioxide (CAS: 1313-27-5) was purchased from Shanghai MacLean Biochemical Technology Co., Ltd.

[0035] Example 1

[0036] A method for preparing a molybdenum trisulfide catalyst, the specific steps are as follows:

[0037] The molybdenum trisulfide catalyst was prepared by acidifying a solution of molybdenum trioxide and sodium sulfide. Molybdenum trioxide (6.95 mmol) was added to 250 ml of an aqueous solution of sodium sulfide (34.74 mmol) to form a bright yellow solution. The solution was then stirred vigorously while slowly adding a 6.0 mol / L aqueous hydrochloric acid solution (about 10 minutes) until the pH of the solution reached 4. At first, the solution darkened; near the end of the addition, a large amount of gaseous hydrogen sulfide was produced. Subsequently, the solution was boiled for 30 minutes to remove the hydrogen sulfide present in the solution. After cooling to room temperature, the solution was filtered and then washed with a large amount of water and ethanol. A damp dark paste was then obtained, and the dark paste was dried in an oven at 80°C for 12 hours to form a black glass solid, which was ground into powder using a mortar to obtain a molybdenum trisulfide catalyst. By Figure 1 C analysis revealed a weak diffraction peak for molybdenum trisulfide, confirming its amorphous state. Figure 1 D, E, analysis of the coordination structure of molybdenum and sulfur elements in molybdenum trisulfide proves that the method described in Example 1 successfully prepared the molybdenum trisulfide catalyst.

[0038] Example 2

[0039] In this example, the catalyst concentration was changed, carbamazepine was selected as a representative of pollutants, and an experiment on the piezoelectric catalytic removal of carbamazepine using a molybdenum trisulfide catalyst was conducted.

[0040] The experimental steps are as follows:

[0041] Prepare 30 mL of 10 mg / L carbamazepine solution in a beaker. Weigh 30 mg of molybdenum trisulfide catalyst powder and add it to the carbamazepine solution. Stir until the adsorption of the carbamazepine solution reaches equilibrium. Place the mixed solution in an ultrasonic cleaner to start the reaction.

[0042] The performance of removing carbamazepine under ultrasonic vibration (power 100 W) in the presence of different concentrations of molybdenum trisulfide catalyst in the examples of the present invention is as follows: Figure 2 As shown. For molybdenum trisulfide catalysts with concentrations of 0.25 g / L, 0.5 g / L, 1 g / L and 2 g / L, the removal rates of carbamazepine under ultrasonic vibration conditions were 45.1%, 75.7%, 99.3% and 92.7%, respectively. With the increase of molybdenum trisulfide dosage, the degradation efficiency of carbamazepine gradually increased. When the concentration reached 2 g / L, the degradation rate tended to decrease, and the optimal molybdenum trisulfide catalyst dosage was 1 g / L.

[0043] These results verified that the optimal catalyst concentration for carbamazepine removal over molybdenum trisulfide catalyst under piezoelectric conditions was 1 g / L.

[0044] Example 3

[0045] In this example, the ultrasonic vibration power was changed, carbamazepine was selected as a representative of pollutants, and an experiment on the piezoelectric catalytic removal of carbamazepine using a molybdenum trisulfide catalyst was conducted.

[0046] The experimental steps are as follows:

[0047] Prepare 30 mL of 10 mg / L carbamazepine solution in a beaker. Weigh 30 mg of molybdenum trisulfide catalyst powder and add it to the carbamazepine solution. Stir until the adsorption of the carbamazepine solution reaches equilibrium. Place the mixed solution in an ultrasonic cleaner to start the reaction.

[0048] In the embodiment of the present invention, at the optimum molybdenum trisulfide catalyst concentration (1 g / L), the performance of removing carbamazepine at different ultrasonic vibration powers is as follows: Figure 3 As shown in the figure. Under the conditions of ultrasonic power of 20 W, 40 W, 60 W, 80 W and 100 W, the removal rates of carbamazepine were 65.1%, 69.7%, 88.1%, 92.9% and 99.3%, respectively. With the increase of ultrasonic vibration power, the degradation efficiency of carbamazepine gradually increased.

[0049] These results confirm that the optimal ultrasonic vibration power for carbamazepine removal over molybdenum trisulfide catalyst under piezoelectric conditions is 100 W.

[0050] Example 4

[0051] In this example, the molybdenum trisulfide catalyst was prepared using Example 1, carbamazepine was selected as a representative of the pollutants, and experiments were conducted on the piezoelectric catalytic removal of carbamazepine using the molybdenum trisulfide catalyst at different times.

[0052] The experimental steps are as follows:

[0053] Prepare 30 mL of 10 mg / L carbamazepine solution in a beaker. Weigh 30 mg of molybdenum trisulfide catalyst and add it to the carbamazepine solution. Stir until the adsorption of the carbamazepine solution reaches equilibrium. Place the mixed solution in an ultrasonic cleaner and start the reaction by ultrasound. The concentration of the molybdenum trisulfide catalyst is 1 g / L and the ultrasonic vibration power is 100W.

[0054] The effect of molybdenum trisulfide catalyst in removing carbamazepine in the present invention is as follows: Figure 4As shown in the figure, it can be seen that the molybdenum trisulfide catalyst has a low adsorption of carbamazepine, with an adsorption of less than 30% within 30 minutes. Ultrasound alone removed 10.8% of carbamazepine within 40 minutes. Adding molybdenum trisulfide catalyst and stirring, 50.8% of carbamazepine can be removed within 40 minutes. In contrast, adding molybdenum trisulfide catalyst and ultrasonic vibration showed excellent effect on carbamazepine removal, with a removal rate of 99.3% within 40 minutes. The results show that molybdenum trisulfide catalyst has an excellent piezoelectric effect, generates a strong built-in electric field, and can significantly improve the removal efficiency of carbamazepine.

[0055] Example 5

[0056] In this example, the molybdenum trisulfide catalyst prepared in Example 1 was used, carbamazepine was selected as a representative of pollutants, and experiments were conducted on the piezoelectric catalytic removal of carbamazepine using the molybdenum trisulfide catalyst under different pH conditions.

[0057] The experimental steps are as follows:

[0058] Prepare 30 mL of 10 mg / L carbamazepine solution in a beaker. Weigh 30 mg of molybdenum trisulfide catalyst powder and add it to the carbamazepine solution. Stir until the adsorption of the carbamazepine solution reaches equilibrium. Place the mixed solution in an ultrasonic cleaner and adjust the power of the ultrasonic cleaner to 100 W to start the reaction. The concentration of the molybdenum trisulfide catalyst is 1 g / L.

[0059] The effect of piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst under different pH conditions in the examples of the present invention is as follows: Figure 5 As shown, under different pH conditions, molybdenum trisulfide catalyst has a high efficiency in removing carbamazepine. At pH = 1, 98.7% of carbamazepine can be removed within 40 minutes, at pH = 3, 93.9% of carbamazepine can be removed within 40 minutes, at pH = 5, 91.6% of carbamazepine can be removed within 40 minutes, at pH = 7, 94.6% of carbamazepine can be removed within 40 minutes, at pH = 9, 89.1% of carbamazepine can be removed within 40 minutes, at pH = 11, 93.4% of carbamazepine can be removed within 40 minutes, and at pH = 13, 93.4% of carbamazepine can be removed within 40 minutes.

[0060] This example shows that molybdenum trisulfide catalyst can efficiently remove carbamazepine by piezoelectric catalysis under different pH environments and has universal applicability under a wide range of pH conditions.

[0061] Example 6

[0062] This example uses the molybdenum trisulfide catalyst prepared in Example 1, selects carbamazepine as a representative of pollutants, and conducts an experiment on the piezoelectric catalytic removal of carbamazepine in real water using the molybdenum trisulfide catalyst.

[0063] The experimental steps are as follows:

[0064] Prepare 30 mL of 10 mg / L carbamazepine solution with rainwater, seawater, tap water and deionized water respectively. Weigh 30 mg of molybdenum trisulfide piezoelectric catalyst powder and add it to the carbamazepine solution, stirring until the adsorption of the carbamazepine solution reaches equilibrium. Place the mixed solution in an ultrasonic cleaner, and adjust the power of the ultrasonic cleaner to 100 W to start the reaction. The concentration of the molybdenum trisulfide catalyst is 1 g / L.

[0065] Figure 6 This is a diagram showing the effect of piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst in real water in an embodiment of the present invention. Experiments show that carbamazepine can be effectively removed from rainwater, seawater, tap water and deionized water in 40 minutes. This example shows that molybdenum trisulfide catalyst can efficiently remove carbamazepine by piezoelectric catalysis in different water environments, which provides a feasible solution for industrial treatment of carbamazepine pollution.

[0066] Example 7

[0067] In this example, the molybdenum trisulfide catalyst prepared in Example 1 was used, carbamazepine was selected as a representative of pollutants, and an experiment on catalyst recycling was conducted.

[0068] The experimental steps are as follows:

[0069] Prepare 30 mL of 10 mg / L carbamazepine solution in a beaker. Weigh 30 mg of molybdenum trisulfide catalyst powder and add it to the carbamazepine solution. Stir until the adsorption of the carbamazepine solution reaches equilibrium. Place the mixed solution in an ultrasonic cleaner and treat it at 100 W for 40 minutes. After the reaction is completed, add carbamazepine solution to make the carbamazepine concentration 10 mg / L, stir again to make the adsorption of the carbamazepine solution reach equilibrium, place the mixed solution in an ultrasonic cleaner, treat it at 100 W for 40 minutes, and repeat the above carbamazepine removal steps. Repeat this experiment five times.

[0070] Figure 7 This is a rendering of the recycling of the catalyst in the piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst in the embodiment of the present invention. The experiment shows that after the molybdenum trisulfide catalyst was recycled five times, the removal efficiency of carbamazepine within 40 minutes dropped from 99.1% to 81.1%, and the performance decreased by about 18%. This example shows that the piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst is recyclable and stable in nature in practical applications.

[0071] Example 8

[0072] In this example, the molybdenum trisulfide catalyst prepared in Example 1 was used, carbamazepine was selected as a representative of pollutants, and a cytotoxicity experiment after catalytic degradation of carbamazepine was conducted.

[0073] The experimental steps are as follows:

[0074] Prepare 30 mL of 10 mg / L carbamazepine solution in a beaker. Weigh 30 mg of molybdenum trisulfide catalyst and add it to the carbamazepine solution. Stir until the adsorption of the carbamazepine solution reaches equilibrium. Place the mixed solution in an ultrasonic cleaner and start the reaction by ultrasound. The concentration of the molybdenum trisulfide catalyst is 1 g / L and the ultrasonic vibration power is 100W.

[0075] Liver cancer cells were selected and cultured to the logarithmic growth phase, and then exposed to pollutants before and after the reaction for 24 hours. CCK-8 cell proliferation detection kit was added for incubation, and the cells were detected at 450 nm using an enzyme reader.

[0076] Figure 8 The figure is a diagram of the cytotoxicity effect of the piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst in the embodiment of the present invention before and after the reaction. The experiment shows that after the molybdenum trisulfide catalyst treats carbamazepine within 40 minutes, the cytotoxicity is reduced compared with that before the reaction. This example shows that the piezoelectric catalytic removal of carbamazepine by molybdenum trisulfide catalyst has the effect of reducing toxicity in practical applications.

[0077] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. The use of molybdenum trisulfide catalyst in catalytic removal of carbamazepine, characterized in that: The steps include: (1) adding a molybdenum trisulfide catalyst to the water to be treated containing carbamazepine and stirring; the concentration of the molybdenum trisulfide catalyst in the water is 0.25-2 g / L; (2) subjecting the water to be treated obtained in step (1) to ultrasonic treatment; the ultrasonic treatment power is greater than 80 W and the time is greater than 30 min; The molybdenum trisulfide catalyst is prepared by stirring a mixture of molybdenum trioxide, sulfide salt and water at high speed while slowly adding acid until a large amount of gaseous hydrogen sulfide is generated, and then drying to obtain a black solid.

2. The use according to claim 1, characterized in that: The concentration of the molybdenum trisulfide catalyst in water is 1.0±0.5 g / L.

3. The use according to claim 2, characterized in that: The power of the ultrasonic treatment is 100±10W, and the time is 40±5min.

4. The use according to any one of claims 1 to 3, characterized in that: The preparation of the molybdenum trisulfide catalyst comprises the following steps: (1) Add molybdenum trioxide to the sulfide salt solution, stir at a high speed of more than 1000 rpm, and slowly add acid solution until the pH value of the solution drops to 4±0.5; (2) boiling the above solution to remove hydrogen sulfide in the solution; Cooling, washing and drying are performed to obtain a black solid, which is then ground into powder to obtain a molybdenum trisulfide catalyst.

5. The use according to claim 4, characterized in that: The molar ratio of molybdenum trioxide to sulfide salt is 1:(3-7).

6. The use according to claim 5, characterized in that: The molar ratio of the molybdenum trioxide to the sulfide salt is 1:

5.

7. The use according to claim 6, characterized in that: The concentration of the sulfide salt aqueous solution is 0.05-0.30 mol / L.

8. The use according to claim 7, characterized in that: The concentration of the sulfide salt aqueous solution is 0.1-0.2 mol / L, and the sulfide salt is sodium sulfide or potassium sulfide; the acidic solution is hydrochloric acid aqueous solution and / or sulfuric acid aqueous solution.

9. The use according to claim 8, characterized in that: The high-speed stirring speed is 1000-4000 rpm; the boiling time is 30±10 minutes; the drying temperature is 80±20° C.; and the drying time is 8-16 hours.

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