Composition for degrading triazole fungicides and application thereof

Abstract

The invention relates to the technical field of sewage treatment, in particular to a composition for degrading triazole bactericides and application of the composition. The invention provides a composition for degrading triazole bactericides. The composition comprises persulfate and a catalyst, the catalyst takes foamed nickel as a carrier and is loaded with a cobalt-nickel layered bimetallic oxide. The cobalt-nickel layered bimetallic oxide is rich in oxygen vacancies, and has a larger specific surface area, higher stability and a higher oxidation reduction rate. In the process of activating sulfate by the cobalt-nickel layered bimetallic oxide, a large amount of free radical sulfate free radical # imgabs0 # superoxide free radical # imgabs1 # and non-free radical singlet oxygen (1O2) are generated, and triazole bactericides are synergistically degraded based on a free radical path and a non-free radical path.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a composition for degrading triazole fungicides and application thereof. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] Triazole fungicides are the largest category of fungicides in the world, with 31 commercial varieties. Among them, tebuconazole, difenoconazole, propiconazole, and myclobutanil are widely used in crops such as cereals, vegetables, and fruits to control fungi in the three major subphyla of basidiomycetes, ascomycetes, and deuteromycetes. Some studies have shown that triazole fungicides have environmental hormone effects, and many countries have included triazole fungicides in the key monitoring list of environmental endocrine disruptors. Triazole fungicides are prone to remain in soil and water, which has an adverse effect on environmental organisms. Therefore, it is becoming increasingly important to eliminate triazole pesticide pollution.

[0004] Chemical degradation has become a major environmental pollution remediation technology due to its low cost and high degradation efficiency. Among them, advanced oxidation technology has shown excellent efficiency and performance. Advanced oxidation technology can produce various free radicals, such as sulfate radicals and hydroxyl radicals, and superoxide radicals can degrade organic pollutants. Recently, people have paid great attention to the treatment of industrial wastewater by persulfate-based advanced oxidation technology.

[0005] Layered double metal oxides (LDO) are obtained by calcining layered double metal hydroxides at a certain temperature. LDO has unique physical and chemical properties and has been widely studied in the fields of adsorption and catalysis. In particular, transition metal LDO is considered to be an effective catalyst for activating persulfate to degrade organic compounds. However, there are no reports on the use of transition metal LDO to activate persulfate to degrade triazole fungicides. Summary of the invention

[0006] In order to overcome the above problems, the present invention provides a composition for degrading triazole fungicides and its application.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] The first aspect of the present invention provides a composition for degrading triazole fungicides, comprising a persulfate and a catalyst; the catalyst uses nickel foam as a carrier and loads cobalt-nickel layered bimetallic oxide.

[0009] The second aspect of the present invention provides use of a composition for degrading triazole fungicides in degrading triazole fungicides.

[0010] The third aspect of the present invention provides a method for degrading triazole fungicides, comprising:

[0011] The composition of the first aspect is applied to the target object to be treated which is contaminated by the triazole fungicide, and the treatment is carried out at room temperature for 20 to 40 minutes.

[0012] The beneficial effects of the present invention are:

[0013] (1) The cobalt-nickel layered bimetallic oxide provided by the present invention is rich in oxygen vacancies, has a larger specific surface area, stronger stability and faster redox rate. In the process of activating sulfate, the cobalt-nickel layered bimetallic oxide generates a large number of free radicals, sulfate radicals (SO · 4 - ), superoxide radicals (O · 2 - ) and non-radical singlet oxygen ( 1 O2), synergistic degradation of triazole fungicides based on free radical pathway and non-free radical pathway.

[0014] (2) The catalyst of the present invention uses nickel foam as a carrier to load cobalt-nickel layered bimetallic oxides. Using nickel foam as a carrier can not only avoid the agglomeration of the layered bimetallic oxides during the calcination synthesis process, but also solve the problem of non-recyclability in the actual water use process, thereby improving the reuse rate of the layered bimetallic oxides.

[0015] (3) The triazole fungicide degradation composition provided by the present invention has excellent degradation activity. When the fungicide concentration is 30 mg / L, 25°C, pH is 7.50, the persulfate concentration is 1.33 mM, and the catalyst amount is 0.99 g / L, the degradation can be completely completed in 40 minutes. At the same time, triazole fungicides such as fluconazole, imazalil, flusilazole and flufenoxazole can be effectively degraded. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0017] Figure 1 XRD pattern of Co-Ni LDO@NF;

[0018] Figure 2SEM images of Co-Ni LDO@NF, where a is the overall SEM image of nickel foam, b is the enlarged local surface of nickel foam, c is the SEM image of Co-Ni LDO@NF, and d is the enlarged SEM image of Co-Ni LDO@NF;

[0019] Figure 3 The effect of different dosages of Co-Ni LDO@NF on the degradation of fluconazole;

[0020] Figure 4 The effect of different dosages of persulfate on the degradation of fluconazole;

[0021] Figure 5 The degradation of fluconazole at different concentrations by persulfate activated Co-Ni LDO@NF;

[0022] Figure 6 This is the cycle performance diagram of Co-Ni LDO@NF;

[0023] Figure 7 Activation of persulfate for Co-Ni LDO@NF to generate sulfate radicals, hydroxyl radicals, superoxide radicals, and singlet oxygen 1 Detection of O2; where a is DMPO-SO4 ·- and DMPO-HO · EPR spectrum of b is DMPO-O2 ·- EPR spectrum of TMPO- 1 EPR spectrum of O2;

[0024] Figure 8 The effect of sulfate in persulfate on the degradation of fluconazole in Co-Ni LDO@NF activation;

[0025] Fig. 9 The degradation diagram of Co-Ni LDO@NF activated persulfate to different triazole fungicides. DETAILED DESCRIPTION

[0026] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0027] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0028] A first typical embodiment of the present invention provides a composition for degrading triazole fungicides, comprising a persulfate and a catalyst; the catalyst uses nickel foam as a carrier and loads a cobalt-nickel layered bimetallic oxide.

[0029] In one or more embodiments, the triazole fungicide includes fluconazole, imazalil, flusilazole and triadimefon.

[0030] In one or more embodiments, the persulfate is selected from one or more of sodium persulfate, potassium persulfate, ammonium persulfate, calcium persulfate and magnesium persulfate, preferably potassium persulfate.

[0031] In one or more embodiments, the mass ratio of the molar number of the persulfate and the catalyst is: (0.33-2 mmol): (0.33-1.66 g), preferably 1.33 mmol: 0.99 g.

[0032] In one or more embodiments, the method for preparing the catalyst comprises:

[0033] (1) dispersing cobalt salt, nickel salt, urea and ammonium fluoride in water, mixing them evenly, adding nickel foam to the mixed solution, performing a hydrothermal reaction, and obtaining a catalyst precursor;

[0034] (2) After calcining the catalyst precursor, the catalyst is obtained.

[0035] Preferably, in step (1), the cobalt salt is selected from cobalt chloride hexahydrate; and the nickel salt is selected from nickel chloride hexahydrate.

[0036] Preferably, in step (1), the molar ratio of the cobalt salt to the nickel salt is 1:(1.8-2.2), preferably 1:2.

[0037] Preferably, in step (1), the molar ratio of cobalt salt to urea and ammonium fluoride is 2:(2.8-3.2):(5.5-6.5), preferably 2:3:6.

[0038] Preferably, in step (1), the concentration of nickel salt in the mixed solution is 0.30-0.37 mol / L, preferably 0.33 mol / L.

[0039] Preferably, in step (1), the temperature of the hydrothermal reaction is 80-100° C., preferably 90° C.; the time of the hydrothermal reaction is 6-10 h, preferably 8 h.

[0040] Preferably, in step (2), the calcination temperature is 300-400° C., preferably 350° C.; the calcination reaction time is 2.5-4 h, preferably 3 h.

[0041] A second typical embodiment of the present invention provides use of a composition for degrading triazole fungicides in degrading triazole fungicides.

[0042] A third typical embodiment of the present invention provides a method for degrading triazole fungicides, comprising:

[0043] The composition of the first aspect is applied to the target object to be treated which is contaminated by the triazole fungicide, and the treatment is carried out at room temperature for 20 to 40 minutes.

[0044] In one or more embodiments, the concentration of the triazole fungicide in the target object to be treated contaminated by the triazole fungicide is 10 to 50 mg / L, preferably 30 mg / L.

[0045] Preferably, based on 30 mg / L triazole fungicide, the concentration of persulfate is 0.33-2 mM, preferably 1.33 mM, and the concentration of catalyst is 0.33-1.66 g / L, preferably 0.99 g / L.

[0046] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with specific embodiments.

[0047] In the following examples of the present invention, the persulfate is potassium persulfate.

[0048] Example 1

[0049] Preparation of catalyst:

[0050] (1) Cut the nickel foam into 5×5 mm sheets and wash them with acetone. Dissolve 0.9691 g Co(NO3)2·6H2O (3.33 mM), 1.9381 g Ni(NO3)2·6H2O (6.66 mM), 0.1852 g NH4F (5 mM) and 0.6006 g CH4N2O (10 mM) in 20 mL of water, place the washed nickel foam at the bottom of a reactor, then pour the mixed solution into the reactor and place it in an oven at 90°C for 8 hours to obtain the catalyst precursor Co-Ni LDH@NF;

[0051] (2) The catalyst precursor Co-Ni LDH@NF was transferred to a tube furnace and calcined at 350 °C for 3 h under protective gas. After natural cooling, the catalyst Co-Ni LDO@NF was obtained.

[0052] Figure 1 The XRD image of Co-Ni LDO@NF shows that Figure 1 The crystal planes of Co-Ni LDO and Ni can be seen in the figure, indicating the successful synthesis of Co-Ni LDO@NF.

[0053] Figure 2 This is the SEM image of Co-Ni LDO@NF. Figure 1 It can be seen that the nickel foam is loaded with cobalt-nickel layered bimetallic oxide.

[0054] Example 2

[0055] Weigh 0.01-0.05 g of Co-Ni LDO@NF into a 50 mL beaker, then add 30 mg / L fluconazole (FLC) and 1.33 mmol / L persulfate, respectively, and stir at room temperature. At regular intervals, take 1 mL of sample from the beaker and put it into a 1.5 mL centrifuge tube that has been pre-added with 0.3 mL of anhydrous ethanol and mix well. Then filter the mixed sample with a 0.22 μm PTFE filter to test the concentration of FLC, which is used to evaluate the catalytic performance of each catalyst. The test results are shown in Figure 2. Figure 3 As shown, from Figure 3 It can be seen that the addition amount of Co-Ni LDO@NF affects the catalytic activity of the composite material, among which the catalyst dosage of 0.99 g / L shows the best catalytic performance. From an economic point of view, the catalyst dosage is finally limited to 0.99 g / L.

[0056] Example 3

[0057] Weigh 49.5 mg Co-Ni LDO@NF into a 50 mL beaker to make the catalyst Co-Ni LDO@NF reach 0.99 g / L, add 30 mg / L fluconazole (FLC) and persulfate respectively, the concentration of persulfate in the solution is 0.33-2 mM, stir at room temperature, take out 1 mL sample from the beaker at regular intervals and put it into a 1.5 mL centrifuge tube with 0.3 mL of anhydrous ethanol added in advance and mix well, then filter the mixed sample with a 0.22 μm PTFE filter membrane to test the concentration of FLC, which is used to evaluate the effect of persulfate on the catalytic performance. The test results are shown in Figure 4 As shown, from Figure 4It can be seen that the amount of persulfate added affects the catalytic activity of the composite material, among which 1.33mM persulfate dosage shows the best catalytic performance. From an economic point of view, the final limit of persulfate dosage is 1.33mM.

[0058] Example 5

[0059] Weigh 49.5 mg Co-Ni LDO@NF into a 50 mL beaker to make the catalyst Co-Ni LDO@NF reach 0.99 g / L, add 10-50 mg / L fluconazole (FLC) and persulfate respectively, the concentration of persulfate in the solution is 1.33 mM, stir at room temperature, take out 1 mL sample from the beaker at regular intervals and put it into a 1.5 mL centrifuge tube with 0.3 mL of anhydrous ethanol added in advance and mix well, then filter the mixed sample with a 0.22 μm PTFE filter membrane to test the concentration of FLC, which is used to evaluate the effect of the amount of pollutants on the catalytic performance. The test results are shown in Figure 5 As shown, from Figure 5 It can be seen that within the same reaction time, as the initial concentration of FLC increases, the degradation efficiency decreases. At an initial concentration of 10-50 mg / L, the degradation efficiency of FLC after 40 minutes of reaction is greater than 80%, and at an initial concentration of 10-20 mg / L, the degradation efficiency reaches 100% within 20 minutes.

[0060] Example 6

[0061] The cyclic performance of the Co-Ni LDO@NF prepared in Example 1 was evaluated. The suspension was separated, washed, and dried to obtain a recycled material. The recycled Co-Ni LDO@NF was subjected to the next degradation process under the same conditions until the third cycle. The details of the cyclic experiment are as follows Figure 6 After three consecutive recovery tests, the degradation rate of FLC was 100%.

[0062] Example 7

[0063] The free radicals of activated persulfate in the prepared Co-Ni LDO@NF were detected by paramagnetic resonance spectrometer. The test results are shown in Figure 7 As shown, DMPO-HO · , DMPO-SO ·- 4. The detection of the signal confirmed the HO · , SO ·- 4 and The presence of triple TEMP- 1 The existence of the characteristic peak of O2 shows that 1 The production of O2 indicates that the active species produced in this catalytic system include free radical SO ·-4. HO · , and non-free radicals 1 O2.

[0064] Example 8

[0065] In the actual degradation process, sulfate in wastewater can capture free radicals to form new free radicals and then compete with pollutants for free radicals, so sulfate in wastewater can affect the degradation effect. In this embodiment, sulfate of different concentrations is added to the reaction system to affect the degradation.

[0066] The reaction system is as follows: in a 50 mL beaker, the concentration of the catalyst Co-Ni LDO@NF is 0.99 g / L, the concentration of fluconazole (FLC) is 30 mg / L, and the concentration of persulfate is 1.33 mM.

[0067] The results are as follows Figure 8 As shown, from Figure 8 It can be seen that the increase in sulfate concentration does not affect the degradation efficiency, indicating that the composition provided by the present invention has a strong anti-interference ability.

[0068] Example 9

[0069] The degradation performance of the prepared Co-Ni LDO@NF activated PMS for different pharmaceutical pollutants was evaluated. In addition to FLC, imazalil, flusilazole and triadimefon were selected as pollutants and degraded under the same conditions. The results are shown in Figure 2. Fig. 9 As shown, at 25°C, 0.99 g / L catalyst, 1.33 mM oxidant concentration, and no pH adjustment, within 40 minutes, 30 mg / L of imazalil, flusilazole, and triadimefon all had good degradation performance, indicating that the composition provided by the present invention has a good degradation effect on a variety of azole fungicides.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A composition for degrading triazole fungicides, characterized in that: The invention comprises persulfate and a catalyst; the catalyst uses foamed nickel as a carrier and carries cobalt-nickel layered bimetallic oxide.

2. The composition according to claim 1, characterized in that The triazole fungicides include fluconazole, imazalil, flusilazole and triadimefon.

3. The composition according to claim 1, characterized in that The persulfate is selected from one or more of sodium persulfate, potassium persulfate, ammonium persulfate, calcium persulfate and magnesium persulfate, preferably potassium persulfate.

4. The composition according to claim 1, characterized in that The mass ratio of the molar number of the persulfate and the catalyst is: (0.33-2 mmol): (0.33-1.66 g), preferably 1.33 mmol: 0.99 g.

5. The composition according to claim 1, characterized in that The preparation method of the catalyst comprises: (1) dispersing cobalt salt, nickel salt, urea and ammonium fluoride in water, mixing them evenly, adding nickel foam to the mixed solution, performing a hydrothermal reaction, and obtaining a catalyst precursor; (2) After calcining the catalyst precursor, the catalyst is obtained.

6. The composition according to claim 1, characterized in that In step (1), the cobalt salt is selected from cobalt chloride hexahydrate; the nickel salt is selected from nickel chloride hexahydrate; Or, in step (1), the molar ratio of the cobalt salt to the nickel salt is 1:(1.8-2.2), preferably 1:2; Or, in step (1), the molar ratio of cobalt salt to urea and ammonium fluoride is 2:(2.8-3.2):(5.5-6.5), preferably 2:3:6; Alternatively, in step (1), the concentration of the nickel salt in the mixed solution is 0.30 to 0.37 mol / L, preferably 0.33 mol / L.

7. The composition according to claim 1, characterized in that In step (1), the temperature of the hydrothermal reaction is 80 to 100° C., preferably 90° C.; the time of the hydrothermal reaction is 6 to 10 hours, preferably 8 hours; Alternatively, the calcination temperature is 300-400° C., preferably 350° C.; the calcination reaction time is 2.5-4 h, preferably 3 h.

8. Use of the composition according to any one of claims 1 to 7 in the degradation of triazole fungicides.

9. A method for degrading triazole fungicides, characterized in that: include: Apply the composition according to any one of claims 1 to 7 to the target object to be treated which is contaminated by triazole fungicides, and treat at room temperature for 20 to 40 minutes.

10. The method according to claim 9, characterized in that The concentration of triazole fungicides in the target object to be treated contaminated by triazole fungicides is 10 to 50 mg / L, preferably 30 mg / L; Preferably, based on 30 mg / L triazole fungicide, the concentration of persulfate is 0.33-2 mM, preferably 1.33 mM, and the concentration of catalyst is 0.33-1.66 g / L, preferably 0.99 g / L.

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