A Fenton-like catalytic system and its application in the degradation of acetaminophen

Abstract

The present application discloses a Fenton-like catalytic system and its application in the degradation of acetaminophen, belonging to the field of water treatment technology. The Fenton-like catalytic system includes MXene and H2O2. The present application adopts MXene with nanometer-scale thickness and submicron or micron-scale lateral dimensions as a catalyst, and couples H2O2 to provide a Fenton-like catalytic system with a larger specific surface area and reaction sites. It can give full play to the Fenton-like catalytic reaction of highly oxygen-philic single vacancies or vacancy cluster defects left in the etching reaction between H2O2 and MXene, accelerate the defect sites to form oxidation clusters by hydrolysis or extraction of oxygen, and is beneficial to the Fenton-like catalytic reaction of H2O2. In the presence or absence of light, effective degradation of acetaminophen can be achieved, meeting the treatment requirements of acetaminophen-containing sewage.

Description

Technical Field

[0001] The present application relates to the field of water treatment technology, and in particular to a Fenton-like catalytic system and its application in the degradation of acetaminophen. Background Art

[0002] In recent years, acetaminophen (ACTP) has gained widespread use as an effective treatment for fever, inflammation, pain, and other conditions. However, due to the release of large quantities of ACTP into aquatic environments during its production and metabolism, its widespread presence in global waterways has become a major water pollution issue facing humanity, significantly harming human health and the ecological environment. Traditional wastewater treatment methods (such as biological methods and physical adsorption) are incapable of completely degrading ACTP. Therefore, an efficient, safe, environmentally friendly, and cost-effective ACTP degradation technology is urgently needed.

[0003] Fenton technology is one of the fastest, most efficient and environmentally friendly advanced oxidation processes for treating wastewater. It can react at room temperature and pressure and has the advantages of fast reaction rate, good degradation effect and simple operation. However, it has problems such as low H2O2 utilization rate, narrow pH application range, and large amount of iron-based sludge, which restrict the development of Fenton technology and make it difficult to meet the treatment requirements of acetaminophen in wastewater. Summary of the Invention

[0004] Based on this, the main purpose of this application is to provide a Fenton-like catalytic system, which uses MXene with nanometer-level thickness and submicron or micron-level lateral dimensions as a catalyst, coupled with H2O2, and has the advantages of high H2O2 utilization, wide pH range, low energy consumption, and low cost. It can effectively degrade acetaminophen in the presence or absence of light, and meet the treatment requirements of wastewater containing acetaminophen.

[0005] In a first aspect of the present application, a Fenton-like catalytic system is provided, comprising MXene and H2O2.

[0006] In some embodiments, the chemical formula of the MXene is M n+1 X n T x ; Wherein, n = 1-3, M is selected from Ti, V, Mo, Sc, Zr, W, Cr, Ta, Nb or Hf; X is C or N; T x is selected from -OH, -F, -Cl or -O.

[0007] In some embodiments, the MXene is Ti3C2T x ; the Ti3C2T x The preparation method comprises:

[0008] mixing lithium fluoride with the first hydrochloric acid solution to prepare a mixed solution;

[0009] The MAX phase material is added to the mixed solution, the etching reaction is carried out, the first centrifugation is performed, the solid phase is washed with a second hydrochloric acid solution, and dried to prepare the Ti3C2T x .

[0010] In some embodiments, the molar concentration of the first hydrochloric acid solution is 6-12 mol / L;

[0011] and / or the mass volume ratio of the lithium fluoride to the first hydrochloric acid solution is 1 g: (10-30) mL;

[0012] and / or the mass ratio of the MAX phase material to the lithium fluoride is (0.3-1):1;

[0013] And / or the molar concentration of the second hydrochloric acid solution is 1-3 mol / L.

[0014] In some embodiments, the conditions for mixing lithium fluoride with the first hydrochloric acid solution include: stirring at a speed of 300-800 rpm for 60-90 min;

[0015] And / or the etching reaction conditions include: reaction at 25-40° C. for 24-72 hours.

[0016] In some embodiments, the drying step further includes an intercalation stripping step; the intercalation stripping step includes:

[0017] The dried solid phase is dispersed in an intercalant, subjected to shearing and exfoliation, and subjected to a second centrifugation. The solid portion is dispersed in water, sonicated, subjected to a third centrifugation, and freeze-dried.

[0018] The intercalant includes at least one of dihydrolevoglucose, dimethyl sulfoxide, N,N-dimethylformamide, acetone, n-hexane and ethanol.

[0019] In some embodiments, the mass ratio of the dried solid phase to the intercalant is 1:(20-30).

[0020] In some embodiments, the shear peeling conditions include: a shearing speed of 4000-8000 rpm and a shearing time of 4-10 h.

[0021] In some embodiments, the conditions of the first centrifugation are: centrifugation at 2500-4000 rpm for 4-10 min;

[0022] and / or the second centrifugation condition is: centrifugation at 8000-15000 rpm for 20-60 min;

[0023] And / or the condition of the third centrifugation is: centrifugation at 3000-5000 rpm for 40-80 min.

[0024] The second aspect of the present application provides the use of the aforementioned Fenton-like catalytic system in the degradation of acetaminophen.

[0025] The third aspect of the present application provides a method for degrading acetaminophen, which uses the aforementioned Fenton-like catalytic system to treat a material to be treated containing acetaminophen.

[0026] The fourth aspect of the present application provides a method for removing acetaminophen in water, comprising the following steps:

[0027] The aforementioned MXene is added to wastewater containing acetaminophen, H2O2 is added, and a visible light source is added or not to carry out the reaction.

[0028] In some embodiments, the mass ratio of the MXene to the acetaminophen-containing wastewater is 1:(5-20);

[0029] And / or the amount of H2O2 added to the wastewater containing acetaminophen is 5-20mM;

[0030] and / or the pH of the wastewater containing acetaminophen is 3-11;

[0031] And / or the power of the visible light source is 200-1000W.

[0032] Beneficial effects of this application:

[0033] 1. The Fenton-like catalytic system of the present application uses MXene with nanometer-scale thickness and submicron or micron-scale lateral dimensions as a catalyst, coupled with H2O2, with a larger specific surface area and reaction sites, and can give full play to the Fenton-like catalytic reaction of highly oxygen-philic single vacancies or vacancy cluster defects left in the etching reaction between H2O2 and MXene, accelerate the defect sites to form oxidized clusters through hydrolysis or extraction of oxygen, and is beneficial to the Fenton-like catalytic reaction of H2O2.

[0034] 2. The Fenton-like catalytic system of the present application can effectively utilize visible light in sunlight, is green and efficient, and has the advantages of high H2O2 utilization rate, wide pH range, low energy consumption, and low cost. It can effectively degrade acetaminophen in the presence or absence of light, meeting the treatment requirements of wastewater containing acetaminophen.

[0035] 3. The Fenton-like catalytic system of the present application has strong visible light absorption and conversion capabilities and a high ACTP removal rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following briefly introduces the drawings required for the embodiments or the prior art description. The drawings are only used to illustrate the preferred embodiments and are not considered to limit the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0037] Figure 1 Ti3C2T of Example 1-2 x SEM images; (a) is a single-layer Ti3C2T x , (b) is the multilayer Ti3C2T of Example 1 x .

[0038] Figure 2 Ti3C2T of Example 1-2 x AFM images of the single-layer Ti3C2T in Example 2. x , (b) is the multilayer Ti3C2T of Example 1 x .

[0039] Figure 3 Ti3C2T of Example 1-2 x Tyndall effect diagram; where (a) is the single-layer Ti3C2T of Example 2 x , (b) is the multilayer Ti3C2T of Example 1 x .

[0040] Figure 4 The degradation curves of ACTP in different systems are shown in Figure 2. Among them, USM is the single-layer Ti3C2T x ; MLM is the multilayer Ti3C2T of Example 1 x .

[0041] Figure 5 Ti3C2T x Effect of addition amount and H2O2 content on the degradation performance of ACTP; wherein USM is the single-layer Ti3C2T x ; MLM is the multilayer Ti3C2T of Example 1 x .

[0042] Figure 6 The effect curve of pH on the degradation performance of ACTP is shown in FIG. 1 , wherein USM is the single-layer Ti3C2T x ; MLM is the multilayer Ti3C2T of Example 1 x . DETAILED DESCRIPTION

[0043] To make the objectives, technical solutions, and advantages of this application more clear and to provide a more thorough and comprehensive understanding of the disclosure of this application, the following will provide a clear and complete description of the technical solutions of this application in conjunction with the specific embodiments of this application and the corresponding drawings. The described embodiments are only part of the embodiments of this application, not all of them.

[0044] The following is a detailed description of the implementation of this application in conjunction with the accompanying drawings. This embodiment is implemented based on the technical solution of this application, and provides a detailed implementation method and specific operation process, but the scope of protection of this application is not limited to the following embodiment.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0046] the term

[0047] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0048] In this application, "a plurality of" or "a plurality of" refers to a number greater than or equal to 2 unless otherwise specified. For example, "one or more" or "at least one" means one or more than or equal to two.

[0049] In this application, "further", "particularly" and the like are used for descriptive purposes to indicate differences in content, but should not be understood as limiting the scope of protection of this application.

[0050] In this application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0051] In this application, when referring to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values within the numerical interval is deemed to be continuous and includes the two numerical endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two numerical endpoints. Unless otherwise specified, when a numerical interval refers only to integers within the numerical interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints, which is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe a feature or characteristic, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical ranges disclosed herein should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. "Numerical interval" allows for a broad range of numerical interval types including percentage intervals, ratio intervals, and ratio intervals.

[0052] In this application, the term "room temperature" generally refers to 4-35° C., preferably 20±5° C. In the examples of this application, room temperature refers to 20-30° C.

[0053] In this application, unless otherwise specified, temperature parameters may be either constant temperature or fluctuating within a certain temperature range. It should be understood that constant temperature processing allows for temperature fluctuations within the precision range of instrument control. Fluctuations within ranges such as ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are permitted.

[0054] In this application, when referring to a range of units, if only the right endpoint is followed by the unit, it means that the units of the left and right endpoints are the same. For example, 2-5h means that the units of the left endpoint "2" and the right endpoint "5" are both hours.

[0055] In a first aspect of the present application, a Fenton-like catalytic system is provided, comprising MXene and H2O2.

[0056] It is understood that the MXene includes a single layer or a multilayer MXene.

[0057] Photo-Fenton catalytic technology mainly uses photochemical reactions and Fenton reactions to degrade and remove pollutants. In the reaction, photocatalysts are used to absorb light-excited electrons to produce active species to promote the photo-Fenton reaction. It can make full use of green solar energy, avoid the generation of sludge, and achieve efficient circulation of H2O2.

[0058] MXene, a new type of two-dimensional transition metal carbide and carbonitride, possesses excellent physical, chemical, and thermal properties. It possesses a variety of functional groups, a large specific surface area, excellent electronic conductivity, and abundant exposed metal sites. In particular, during the preparation of MXene, the etching process to remove the Al layer of the MAX phase material occasionally strips away transition metal atoms, leaving behind highly oxygen-affinity single vacancies or vacancy clusters. These defect sites readily form oxidized clusters through hydrolysis or oxygen extraction, facilitating Fenton-like catalytic reactions with H2O2. MXene also possesses strong visible light absorption and conversion capabilities, making full use of green solar energy under visible light conditions to achieve more effective removal of ACTP.

[0059] MXene nanosheets prepared by conventional methods are smaller in size and have fewer reaction sites. In comparison, this application uses MXene with nanometer-scale thickness and submicron or micron-scale lateral dimensions as a catalyst, coupled with H2O2, which has a larger specific surface area and reaction sites. This can fully utilize the Fenton-like catalytic reaction of highly oxygen-philic single vacancies or vacancy cluster defects left in the etching reaction between H2O2 and MXene, accelerate the formation of oxidized clusters through hydrolysis or extraction of oxygen at the defect sites, and is conducive to the Fenton-like catalytic reaction of H2O2. Specifically, the average thickness of MXene can be 1-500nm, and the average lateral dimension can be 0.3-12μm.

[0060] In some embodiments, the chemical formula of the MXene is M n+1 X n T x ; Wherein, n = 1-3, M is selected from Ti, V, Mo, Sc, Zr, W, Cr, Ta, Nb or Hf; X is C or N; T x is selected from -OH, -F, -Cl or -O.

[0061] In some embodiments, the MXene is Ti3C2T x ; the Ti3C2T x The preparation method comprises:

[0062] mixing lithium fluoride with the first hydrochloric acid solution to prepare a mixed solution;

[0063] The MAX phase material is added to the mixed solution, the etching reaction is carried out, the first centrifugation is performed, the solid phase is washed with a second hydrochloric acid solution, and dried to prepare the Ti3C2T x .

[0064] It is understood that there are no specific requirements for the specific type of MAX phase material. In some embodiments, in the MAX phase material, M is selected from Ti, V, Mo, Sc, Zr, W, Cr, Ta, Nb, or Hf, X is C or N, and A is Al or Si. MAX phase materials can be commercially available or prepared in-house.

[0065] Optionally, the molar concentration of the first hydrochloric acid solution is 6-12 mol / L, specifically 6 mol / L, 7 mol / L, 8 mol / L, 9 mol / L, 10 mol / L, 11 mol / L, 12 mol / L, etc.; the mass volume ratio of the lithium fluoride to the first hydrochloric acid solution is 1 g:(10-30) mL, specifically 1 g:10 mL, 1 g:15 mL, 1 g:20 mL, 1 g:25 mL, 1 g:30 mL, etc.; the mass ratio of the MAX phase material to the lithium fluoride is (0.3-1):1, specifically 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, etc.; the molar concentration of the second hydrochloric acid solution is 1-3 mol / L, specifically 1 mol / L, 1.5 mol / L, 2 mol / L, 2.5 mol / L, 3 mol / L, etc.

[0066] Optionally, the conditions for mixing the lithium fluoride with the first hydrochloric acid solution include: stirring at a speed of 300-800 rpm for 60-90 min, and the stirring speed can specifically be 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, or 800 rpm; the stirring time can specifically be 60 min, 70 min, 80 min, 90 min, etc.; the conditions for the etching reaction include: reacting at 25-40°C for 24-72h, specifically, reacting at 25°C, 30°C, 35°C, or 40°C for 24h, 30h, 36h, 42h, 48h, 54h, 60h, 66h, or 72h.

[0067] In some embodiments, the drying step further includes an intercalation stripping step; the intercalation stripping step includes:

[0068] The dried solid phase is dispersed in an intercalant, subjected to shearing and exfoliation, and subjected to a second centrifugation. The solid portion is dispersed in water, sonicated, subjected to a third centrifugation, and freeze-dried.

[0069] The intercalant includes at least one of dihydrolevoglucose, dimethyl sulfoxide, N,N-dimethylformamide, acetone, n-hexane and ethanol.

[0070] Understandably, the intercalation and exfoliation steps can exfoliate multilayer MXene into single-layer MXene, which has more reactive sites than multilayer MXene. The intercalation agent, dihydro-levulinone, is a green solvent and chemical raw material containing functional groups such as hydroxyl and carbonyl groups, which can interact with the functional groups on the MXene surface to achieve intercalation and exfoliation to obtain a single-layer MXene.

[0071] In some embodiments, the mass ratio of the dried solid phase to the intercalant is 1:(20-30), specifically 1:20, 1:22, 1:24, 1:26, 1:28, 1:30, etc.

[0072] In some embodiments, the shear peeling conditions include: a shear speed of 4000-8000 rpm, and a shear time of 4-10 h; specifically, the shear speed can be 4000 rpm, 5000 rpm, 6000 rpm, 7000 rpm, 8000 rpm, etc.; the shear time can be 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, etc.

[0073] Optionally, the first centrifugation condition is: centrifugation at 2500-4000 rpm for 4-10 min, specifically centrifugation at 2500 rpm, 3000 rpm, 3500 rpm or 4000 rpm for 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min; the second centrifugation condition is: centrifugation at 8000-15000 rpm for 20-60 min, specifically centrifugation at 8000 rpm, 9000 rpm, 10000 rpm, 1100 The conditions for the third centrifugation are: centrifugation at 3000-5000 rpm for 40-80 min, specifically centrifugation at 3000 rpm, 3500 rpm, 4000 rpm, 4500 rpm or 5000 rpm for 40 min, 50 min, 60 min, 70 min or 80 min.

[0074] The second aspect of the present application provides the use of the aforementioned Fenton-like catalytic system in the degradation of acetaminophen.

[0075] The third aspect of the present application provides a method for degrading acetaminophen, which uses the aforementioned Fenton-like catalytic system to treat a material to be treated containing acetaminophen.

[0076] It can be understood that the acetaminophen-containing material to be treated includes wastewater containing acetaminophen.

[0077] The fourth aspect of the present application provides a method for removing acetaminophen in water, comprising the following steps:

[0078] The aforementioned MXene is added to wastewater containing acetaminophen, H2O2 is added, and a visible light source is added or not to carry out the reaction.

[0079] Optionally, the mass ratio of the MXene to the wastewater containing acetaminophen is 1:(5-20), specifically 1:5, 1:10, 1:15, 1:20, etc.; the amount of H2O2 added to the wastewater containing acetaminophen is 5-20mM, specifically 5mM, 10mM, 15mM, 20mM, etc.; the pH of the wastewater containing acetaminophen is 3-11, specifically 3, 4, 5, 6, 7, 8, 9, 10, 11, etc., preferably, the pH is 3-7; the power of the visible light source is 200-1000W, specifically 200W, 300W, 400W, 500W, 600W, 700W, 800W, 900W or 1000W.

[0080] Unless otherwise specified, the raw materials used in the following experiments can be purchased from the market. The following is an illustrative description of some of the raw materials used in the examples:

[0081] MAX phase material: Ti3AlC2, purchased from McLean Company.

[0082] The following are specific examples.

[0083] Example 1

[0084] Multilayer Ti3C2T x The specific steps of (MXene) are:

[0085] 1) Sieve the MAX phase material to a particle size of ≤200 mesh;

[0086] 2) Prepare 9M hydrochloric acid solution and 2M hydrochloric acid solution;

[0087] 3) Add 2.5 g of lithium fluoride to 50 mL of 9 M hydrochloric acid solution and stir continuously at 500 rpm for 1 h to allow the reaction to proceed uniformly to obtain a mixed solution;

[0088] 4) Slowly add 1.25 g of MAX material that meets the requirements after screening to the mixed solution in step 3), avoiding boiling and splashing of the solution;

[0089] 5) The solution obtained in step 4) was placed in a water bath at 40°C for 48 hours to perform an etching reaction;

[0090] The solution of step (5) after the etching reaction was centrifuged at 3500 rpm for 5 minutes, the supernatant was discarded, and the solution was washed several times with the 2M hydrochloric acid solution of step 2), the supernatant was discarded, and the solution was washed several times with water until the pH was ≥ 6. The precipitate was collected and dried in a vacuum drying oven at 60 ° C for 24 h to obtain multilayer Ti3C2T x (MXene), denoted as MLM.

[0091] The obtained multilayer Ti3C2T x The SEM and AFM morphology and Tyndall effect of (MXene) are shown in Figure 2. Figure 1-3 shown.

[0092] Example 2

[0093] Single-layer Ti3C2T x The specific steps of (MXene) are:

[0094] 1) The multilayer Ti3C2T prepared in Example 1 x (MXene) was added to dihydro-levulinic ketone at a solid-liquid ratio of 1:25 (mass ratio) to obtain a uniform dispersion;

[0095] 2) Exfoliate the homogenized dispersion from step 1) using a high shear mixer (Silverson L5M) at 6000 rpm for 6 hours at room temperature (using an ice bath to absorb excess heat generated during the process);

[0096] 3) The black dispersion obtained after peeling in step 2) was centrifuged at 10000 rpm for 30 minutes, and the upper intercalation liquid was discarded to obtain peeled few layers and unpeeled thin sheets; the peeled few layers and unpeeled Ti3C2T x The (MXene) flakes were redispersed in pure water and ultrasonicated in an ice bath under N2 atmosphere for 2 h to completely peel off the single layer Ti3C2T x (MXene), the resulting solution was centrifuged at 4000 rpm for 60 min, and the supernatant was collected;

[0097] 4) To avoid the drying of the prepared single-layer Ti3C2T x The (MXene) flakes were stacked to maintain the morphology and form in the solution to the greatest extent possible, and then dried in a freeze dryer at -45~-50℃ for 24h to obtain a single layer of Ti3C2T x (MXene), denoted as USM.

[0098] The obtained single-layer Ti3C2T x The SEM and AFM morphology and Tyndall effect of (MXene) are shown in Figure 2. Figure 1-3 shown.

[0099] Example 3

[0100] The single-layer and multi-layer Ti3C2T prepared in Example 1 and Example 2 were used respectively. x (MXene) was used as a catalyst, coupled with H2O2 and / or light to provide a Fenton-like reaction system, and its degradation performance for wastewater containing acetylaminophenol was studied.

[0101] The simulated wastewater with an initial concentration of 5 mg / L ACTP solution was prepared to study the effect of Ti3C2T x , H2O2 and light on the degradation effect of ACTP, wherein the Ti3C2T x Add H2O2 at a solid-liquid ratio of 1:5 (mass ratio), with an amount of 15 mM, and react for 1 hour in the absence of light or with a 350 W visible light source.

[0102] The pH of the simulated phosphorus-containing wastewater was around 5.7 before the experiment, and around 5 after the experiment.

[0103] After the experiment, the concentration of ACTP was measured and the removal rate was calculated.

[0104] Removal rate calculation formula: Formula (1);

[0105] In formula (1), ŋ is the removal rate (%); C0, C e are the initial phosphorus concentration before treatment and the phosphorus concentration after treatment (mg / L), respectively.

[0106] The experimental results are as follows Figure 4 As shown in the figure, A represents the degradation effect of ACTP when only H2O2 is added; B represents the degradation effect of ACTP when only light is irradiated; C represents the degradation effect of ACTP when only H2O2 and light are added; D represents the degradation effect of ACTP when only a single layer of Ti3C2T is added x Degradation effect of ACTP with (MXene) (USM) and H2O2; E represents the addition of multilayer Ti3C2T x Degradation effect of ACTP on (MXene) (MLM) and H2O2; F represents single-layer Ti3C2T x Degradation effect of ACTP by photocatalytic Fenton-like system of (MXene)(USM) coupled with H2O2 and light; G represents multilayer Ti3C2T x Degradation effect of ACTP on the photocatalytic Fenton-like system of (MXene)(MLM) coupled with H2O2 and light.

[0107] from Figure 4It can be seen that: when using H2O2 or light alone, ACTP is almost not degraded. When light is coupled with H2O2, under no light conditions, single or multilayer Ti3C2T x Coupling with H2O2 can significantly improve the degradation efficiency of ACTP; under light, single or multilayer Ti3C2T x Coupling with H2O2 can greatly improve the degradation efficiency of ACTP, and the removal rate can reach 100% in 60 minutes. x It can be used as a catalyst to couple H2O2, and is beneficial to the Fenton-like catalytic reaction of H2O2 under conditions of light or no light, thereby improving the degradation efficiency of ACTP.

[0108] Example 4

[0109] The single-layer and multi-layer Ti3C2T prepared in Example 1 and Example 2 were used respectively. x (MXene) is used as a catalyst, coupled with H2O2 and light to provide a photocatalytic Fenton reaction system, and the performance evaluation of degrading acetaminophenol wastewater is explored when the optimal catalyst addition amount and the optimal H2O2 content are used.

[0110] Prepare simulated wastewater with an initial concentration of 5 mg / L ACTP solution, add the materials prepared in Examples 1 and 2, respectively, add 5, 10, 15, 20, 25, and 30 mg of catalyst (100 mL of simulated wastewater), add 0, 5, 10, 15, and 20 mM H2O2, turn on a 350 W visible light source, and react for 1 h.

[0111] After the experiment, the concentration of ACTP was measured and the removal rate was calculated.

[0112] The experimental results are as follows Figure 5 As shown in the figure, it can be seen that the removal rate of ACTP increases with the increase in the amount of catalyst and H2O2. x and the single-layer Ti3C2T of Example 2 x For example, when the amount of catalyst added reaches 20 mg and the concentration of H2O2 reaches 15 mM, the removal rate of ACTP can reach 100%.

[0113] Example 5

[0114] The single-layer and multi-layer Ti3C2T prepared in Example 1 and Example 2 were used respectively. x (MXene) was used as a catalyst, coupled with H2O2 and light to provide a photocatalytic Fenton reaction system, and the effects of the pH of the initial ACTP solution and other conditions on the degradation performance of ACTP wastewater were investigated.

[0115] Simulated wastewater with an initial concentration of 5 mg / L ACTP solution was prepared (pH adjusted to 3, 5, 7, 9, and 11), and the materials prepared in Examples 1 and 2 were added respectively. 15 mM H2O2 was added at a solid-liquid ratio of 1:5, and a 350 W visible light source was turned on for 1 h.

[0116] The experimental results are as follows Figure 6 As shown, it can be seen that the photocatalytic Fenton reaction systems corresponding to Examples 1-2 have a certain removal effect under the conditions of pH 3-11, among which the removal rate under alkaline conditions is lower than that under acidic and neutral conditions. The treatment effect is optimal when the initial pH of the ACTP solution is 5.

[0117] Example 6

[0118] The single-layer and multi-layer Ti3C2T prepared in Example 1 and Example 2 were used respectively. x (MXene) is used as a catalyst, coupled with H2O2 and light to provide a photocatalytic Fenton reaction system to explore the processing efficiency of reuse.

[0119] Prepare simulated wastewater with an initial concentration of 5 mg / L ACTP solution, and add the Ti3C2T x Add H2O2 at a solid-liquid ratio of 1:5 (mass ratio), the amount of H2O2 is 15mM, turn on the 350W visible light source, and react for 1 hour. After the reaction is completed, centrifuge and separate the Ti3C2T x The mixture was freeze-dried at -50°C, ground, and subjected to ACTP degradation treatment again according to the above conditions. The results are shown in Table 1.

[0120] Table 1 Repeated treatment efficiency of photocatalytic Fenton reaction system

[0121]

[0122] It can be seen from Table 1 that the Ti3C2T x After repeated use for five times, the removal rates of ATCP can reach 69.7% and 62.1% respectively. x It can be reused and has good stability.

[0123] In summary, the Ti3C2T x Coupling H2O2, or simultaneously coupling H2O2 and light, can effectively remove ATCP and has good reusability. x Compared with the single-layer Ti3C2T xIt has comparable ATCP degradation performance and better reusability. This shows that when using MXene with nanometer-scale thickness and submicron or micron-scale lateral dimensions as a Fenton-like catalyst, the use of multilayer MXene, which has a simpler preparation process, can achieve technical results comparable to or even better than those of single-layer MXene.

[0124] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0125] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A Fenton-like catalytic system, characterized in that: Including MXene and H2O2; the MXene is Ti3C2T x ;T x Selected from -OH, -F, -Cl or -O; The Ti3C2T x The preparation method comprises: mixing lithium fluoride with the first hydrochloric acid solution to prepare a mixed solution; The MAX phase material is added to the mixed solution, an etching reaction is carried out, a first centrifugation is performed, the solid phase is washed with a second hydrochloric acid solution, and dried to prepare the Ti3C2T x ; After the drying step, the step of intercalation stripping is also included; The intercalation stripping step comprises: The dried solid phase is dispersed in an intercalant, subjected to shearing and exfoliation, and subjected to a second centrifugation. The solid portion is dispersed in water, sonicated, subjected to a third centrifugation, and freeze-dried. The intercalant is dihydro-levulinone.

2. The Fenton-like catalytic system according to claim 1, wherein The molar concentration of the first hydrochloric acid solution is 6-12 mol / L; and / or the mass volume ratio of the lithium fluoride to the first hydrochloric acid solution is 1 g:(10-30) mL; and / or the mass ratio of the MAX phase material to the lithium fluoride is (0.3-1):1; and / or the molar concentration of the second hydrochloric acid solution is 1-3 mol / L; and / or the conditions for mixing the lithium fluoride with the first hydrochloric acid solution include: stirring at a speed of 300-800 rpm for 60-90 min; And / or the etching reaction conditions include: reaction at 25-40° C. for 24-72 hours.

3. The Fenton-like catalytic system according to claim 1, wherein The mass ratio of the dried solid phase to the intercalant is 1:(20-30); And / or the shear peeling conditions include: shearing speed of 4000-8000 rpm, shearing time of 4-10 hours; and / or the first centrifugation condition is: centrifugation at 2500-4000 rpm for 4-10 min; and / or the second centrifugation condition is: centrifugation at 8000-15000 rpm for 20-60 min; And / or the condition of the third centrifugation is: centrifugation at 3000-5000 rpm for 40-80 min.

4. Use of the Fenton-like catalytic system according to any one of claims 1 to 3 in the degradation of acetaminophen.

5. A method for degrading acetaminophen, characterized in that: The Fenton-like catalytic system according to any one of claims 1 to 3 is used to treat a material to be treated containing acetaminophen.

6. The method according to claim 5, wherein The paracetamol-containing material to be treated includes wastewater containing paracetamol.

7. A method for removing acetaminophen in water, characterized in that: The steps include: The MXene according to any one of claims 1 to 3 is added to wastewater containing acetaminophen, H2O2 is added, and a visible light source is added or not added to carry out a reaction.

8. The method according to claim 7, wherein The mass ratio of the MXene to the wastewater containing acetylaminophenol is 1:(5-20); And / or the amount of H2O2 added to the wastewater containing acetaminophen is 5-20mM; and / or the pH of the wastewater containing acetaminophen is 3-11; And / or the power of the visible light source is 200-1000W.

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