Method for green detection of catalytic performance of efficient catalyst

Abstract

The invention provides a method for green detection of catalytic performance of a high-efficiency catalyst. The method comprises the following steps: S1, preparing a catalyst-oxidant-methylene blue solution; s2, diluting the oxidant-catalyst-methylene blue solution obtained in the step S1, and testing the absorbance through an ultraviolet spectrophotometer; and S3, evaluating the catalytic oxidation property of the catalyst in the solution according to the degradation rate of methylene blue. The experimental method provided by the invention overcomes the problems of methylene blue flocculation, complex test method, long test time, non-environmental protection and the like in conventional tests. The test method provided by the invention can simply, conveniently, quickly, greenly and accurately test the catalytic performance of the catalyst.

Description

Technical Field

[0001] The invention belongs to the technical field of catalytic oxidation, and in particular relates to a method for green detection of catalytic performance of a high-efficiency catalyst. Background Art

[0002] Catalysts, also known as catalysts, refer to substances that can change the chemical reaction rate of other substances in a chemical reaction, which can increase or decrease the chemical reaction rate, but whose quality and chemical properties do not change before and after the chemical reaction. Catalysts can be divided into three types, namely homogeneous catalysts, heterogeneous catalysts and biocatalysts. Among them, the physical state of homogeneous catalysts and the reactants they catalyze is consistent; while the state of heterogeneous catalysts and the reactants they catalyze is different. Biocatalysts, referred to as enzymes, are organic substances with catalytic ability produced by animals, plants and microorganisms. Catalysts play a vital role in the development of the chemical industry and society. According to incomplete statistics, about 30,000 raw materials and chemical intermediates in the world are directly and indirectly synthesized by catalysts. In addition to being directly related to people's food, clothing, housing and transportation, these materials also involve modern high-tech fields such as information transmission, network technology, aerospace, and bioengineering. Therefore, it is very necessary to quickly, accurately and conveniently detect the catalytic performance of catalysts.

[0003] CN201710056840.3 mentions a method for evaluating catalytic performance by differential thermal analysis, which combines the oxidation and reduction processes to characterize the catalytic performance. In the characterization, the oxidation and reduction processes are combined to establish a characterization analysis method, which is complicated to operate, requires high-temperature heating, is costly, and is not easy to operate.

[0004] CN201710056828.2 mentions a method for evaluating catalysts using thermal analysis. The method for evaluating catalysts using thermal analysis continuously detects the differential thermal signals (TPR-TPO-DTA) of catalyst samples during programmed temperature reduction and programmed temperature oxidation in situ. This is also thermal analysis, which is costly and difficult to operate.

[0005] CN201710056836.7 mentions a method for evaluating catalysts using differential thermogravimetric analysis, during which a thermogravimetric analyzer records the weight change rate of the sample to form a TPO-DTG curve. The detection is complex and costly. Invention content

[0006] In view of this, the present invention aims to propose a method for green detection of catalytic performance of high-efficiency catalysts to solve at least one technical problem in the background technology.

[0007] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0008] A method for green detection of catalytic performance of a high-efficiency catalyst comprises the following steps: S1: preparing a catalyst-oxidant-methylene blue solution;

[0009] S2: diluting the oxidant-catalyst-methylene blue solution obtained in step S1, and then testing the absorbance by a UV spectrophotometer;

[0010] S3: Evaluate the catalytic oxidizing property of the catalyst in the solution based on the degradation rate of methylene blue.

[0011] Furthermore, in step S1, the oxidant is H2O2.

[0012] Further, the concentration of the oxidant is 0.01-10 wt %; preferably, the concentration of the oxidant is 0.1-2 wt %.

[0013] Furthermore, the catalyst in step S1 is one or more of the elements or element compounds containing iron, copper, manganese, zinc, and vanadium. 2+ , Cu 2+ , Mn 2+ ,Mg 2+ , Zn 2+ , VO3 2- , Fe, Fe2O3, Fe3O 4。

[0014] Furthermore, the catalyst concentration in step S1 is 0-1 mol / L, preferably, the catalyst concentration is 0-200 mmol / L.

[0015] Furthermore, in step S1, the concentration of methylene blue is 0.01-150000 μmol / L, and the preferred concentration of methylene blue is 1-150000 μmol / L.

[0016] Furthermore, the oxidant-catalyst-methylene blue solution in step S2 is diluted by a multiple of 0-10000 times, preferably, the dilution multiple is 0-1000 times.

[0017] Furthermore, the test wavelength of the absorbance tested by the ultraviolet spectrophotometer in step S2 is 200-1000 nm, preferably, the test wavelength is 660 nm.

[0018] Furthermore, the catalytic performance of the catalyst in the solution was evaluated according to the degradation rate of methylene blue, and the catalytic performance of the catalyst in the solution was positively correlated with the degradation rate of methylene blue.

[0019] Compared with the prior art, the green method for detecting the catalytic performance of a high-efficiency catalyst created by the present invention has the following advantages:

[0020] 1. All reagents used in this application are green, environmentally friendly and harmless.

[0021] 2. The test method of the present application is convenient and quick and avoids the problem of methylene blue flocculation, thereby ensuring the accuracy of the test results.

[0022] 3. The present application can quickly and accurately characterize the catalytic performance of the catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0024] Figure 1 is the absorption peak of methylene blue at different wavelengths described in the present invention;

[0025] Figure 2 The Fe at different wavelengths described in Comparative Example 1 of the present invention 2+ The absorption peak of

[0026] Figure 3 The Fe at different wavelengths described in Comparative Example 2 of the present invention 3+ The absorption peak of

[0027] Figure 4 is the absorption peak of H2O2 at different wavelengths described in Comparative Example 3 of the present invention;

[0028] Figure 5 is the absorbance standard curve of methylene blue described in Example 2 of the present invention;

[0029] Figure 6 This is the methylene blue dilution standard curve described in Example 3 of the present invention. DETAILED DESCRIPTION

[0030] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0031] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0032] Example 1

[0033] This embodiment provides a method for green detection of the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is only that: the absorption curve of methylene blue at a wavelength of 200-800nm, such as Figure 1 shown.

[0034] Example 2

[0035] This embodiment provides a method for green detection of the catalytic performance of a high-efficiency catalyst for rapid and accurate determination of the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is only that the absorbance of methylene blue with a concentration of 0-150 μmol / L is tested at a wavelength of 660 nm, such as Figure 5 shown.

[0036] The concentrations of methylene blue were 0μmol / L, 0.1μmol / L, 0.5μmol / L, 1μmol / L, 5μmol / L, 10μmol / L, 20μmol / L, 30μmol / L, 40μmol / L, 50μmol / L, 60μmol / L, 70μmol / L, 80μmol / L, 100μmol / L, 120μmol / L, and 150μmol / L.

[0037] Example 3

[0038] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance of methylene blue with a concentration of 0-150 mmol / L and diluted 0-1000 times is tested at a wavelength of 660 nm. Figure 6 As shown; the concentration of methylene blue is 1μmol / L, 10μmol / L, 50μmol / L, 100μmol / L, 150μmol / L, 500μmol / L, 1000μmol / L, 1500μmol / L, 5000μmol / L, 10000μmol / L, 15000μmol / L, 50000μmol / L, 100000μmol / L, 150000μmol / L.

[0039] Example 4

[0040] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is carried out at a wavelength of 660nm, wherein the concentration of methylene blue is 150mmol / L, and the catalyst (Fe 2+ ) concentration is 5mmol / L, the concentration of the oxidant H2O2 is 1wt%, diluted 1000 times.

[0041] Example 5

[0042] This embodiment provides a green method for detecting the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is only that: the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 30μmol / L, the concentration of the catalyst (Fe2O3-30nm) is 5mmol / L, and the concentration of the oxidant H2O2 is 1.2wt%, without dilution.

[0043] Comparative Example 1

[0044] This embodiment provides a method for green detection of the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is that: Fe 2+ Absorption curves of Fe at different wavelengths 2+ The absorption peak of Figure 2 shown.

[0045] Comparative Example 2

[0046] This embodiment provides a method for green detection of the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is that: Fe 3+ Absorption curves of Fe at different wavelengths 3+ The absorption peak of Figure 3 shown.

[0047] Comparative Example 3

[0048] This embodiment provides a method for green detection of the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is only that: the absorption curve of H2O2 at a wavelength of 200-800nm, the absorption peaks of H2O2 at different wavelengths are as follows: Figure 4 shown.

[0049] Comparative Example 4

[0050] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 150μmol / L, and the catalyst (Fe 2+ ) concentration is 3mmol / L, and the concentration of the oxidant H2O2 is 1wt%, without dilution.

[0051] Comparative Example 5

[0052] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 150μmol / L, and the catalyst (Cu 2+ ) concentration is 3mmol / L, and the concentration of the oxidant H2O2 is 1wt%, without dilution.

[0053] Comparative Example 6

[0054] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 150μmol / L, and the catalyst (Mn 2+ ) concentration is 3mmol / L, and the concentration of the oxidant H2O2 is 1wt%, without dilution.

[0055] Comparative Example 7

[0056] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 150μmol / L, and the catalyst (Mg 2+ ) concentration is 3mmol / L, and the concentration of the oxidant H2O2 is 1wt%, without dilution.

[0057] Comparative Example 8

[0058] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 150μmol / L, and the catalyst (Zn 2+ ) concentration is 3mmol / L, and the concentration of the oxidant H2O2 is 1wt%, without dilution.

[0059] Comparative Example 9

[0060] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 150μmol / L, and the catalyst (VO3 2- ) concentration is 3mmol / L, and the concentration of the oxidant H2O2 is 1wt%, without dilution.

[0061] Comparative Example 10

[0062] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is carried out at a wavelength of 660nm, wherein the concentration of methylene blue is 150mmol / L, and the catalyst (Fe 2+ ) concentration is 1mmol / L, the concentration of the oxidant H2O2 is 1wt%, diluted 1000 times.

[0063] Comparative Example 11

[0064] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is carried out at a wavelength of 660nm, wherein the concentration of methylene blue is 150mmol / L, and the catalyst (Fe 2+ ) concentration is 2mmol / L, the concentration of the oxidant H2O2 is 1wt%, diluted 1000 times.

[0065] Comparative Example 12

[0066] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is carried out at a wavelength of 660nm, wherein the concentration of methylene blue is 150mmol / L, and the catalyst (Fe 2+ ) concentration is 40mmol / L, the concentration of the oxidant H2O2 is 1wt%, diluted 1000 times.

[0067] Comparative Example 13

[0068] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is carried out at a wavelength of 660nm, wherein the concentration of methylene blue is 150mmol / L, and the catalyst (Fe 2+ ) concentration is 100mmol / L, the concentration of the oxidant H2O2 is 1wt%, diluted 1000 times.

[0069] Comparative Example 14

[0070] This embodiment provides a green method for detecting the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is only that: the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 30μmol / L, the concentration of the catalyst (Fe-100nm) is 10mmol / L, and the concentration of the oxidant H2O2 is 1.2wt%, without dilution.

[0071] Comparative Example 15

[0072] This embodiment provides a green method for detecting the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is only that: the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 30μmol / L, the concentration of the catalyst (Fe3O4-30nm) is 3.33mmol / L, and the concentration of the oxidant H2O2 is 1.2wt%, without dilution.

[0073] Comparative Example 16

[0074] This embodiment provides a green method for detecting the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is only that: the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 30μmol / L, the concentration of the catalyst (Fe2O3-20nm) is 5mmol / L, and the concentration of the oxidant H2O2 is 1.2wt%, without dilution.

[0075] Comparative Example 17

[0076] This embodiment provides a green method for detecting the catalytic performance of a high-efficiency catalyst to quickly and accurately determine the catalytic performance of the catalyst. The difference between the test method and the method provided in the specific implementation method is only that: the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 30μmol / L, the concentration of the catalyst (Fe2O3-100nm) is 5mmol / L, and the concentration of the oxidant H2O2 is 1.2wt%, without dilution.

[0077] Comparative Example 18

[0078] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 176μmol / L, and the catalyst (Fe 2+ ) concentration is 0.12mmol / L, and the concentration of the oxidant H2O2 is 0.09wt%, without dilution.

[0079] Comparative Example 19

[0080] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 750μmol / L, and the catalyst (Fe 2+ ) concentration is 3mmol / L, and the concentration of the oxidant H2O2 is 0.5wt% without dilution.

[0081] Comparative Example 20

[0082] This embodiment provides a method for green detection of catalytic performance of high-efficiency catalysts to quickly and accurately determine the catalytic performance of catalysts. The difference between the test method and the method provided in the specific implementation method is that the absorbance test is performed at a wavelength of 660nm, wherein the concentration of methylene blue is 50μmol / L, and the catalyst (VO3 2- ) concentration is 2mmol / L, and the concentration of the oxidant H2O2 is 0.5wt% without dilution.

[0083] Table 1 Effect table of Examples 4-5 and Comparative Examples 1-20

[0084]

[0085]

[0086] The present invention can be seen from Example 1 and Comparative Examples 1-3 that at the test wavelength of 660nm, the present method can effectively and accurately determine the absorption peak of different types of methylene blue, which is the strongest and is not affected by the catalyst Fe. 2+ , the influence of the oxidant H2O2, which ensures the accuracy of the experimental results, and the curve equation is obtained through Example 2. It can be seen from Example 3 that the error of the effect of dilution on the concentration of methylene blue is basically small, which further illustrates that this test method ensures the accuracy of the test results.

[0087] The test results of Comparative Examples 4-9 in this application show the catalytic performance of different types of catalysts, among which Fe 2+ The catalytic effect on the oxidant H2O2 is the best. The test results of Example 4, Comparative Example 4, and Comparative Examples 10-13 show that the catalyst Fe 2+ The concentration of H2O2 affects the catalytic effect. 2+ The catalytic effect on H2O2 is best when the concentration is 5mmol / L.

[0088] The present application shows the catalytic effects of different catalysts in heterogeneous catalysis through Example 5 and Comparative Examples 14-15, among which Fe2O3 in Example 5 has the best catalytic effect on H2O2. The test results of Example 5 and Comparative Examples 16-17 show that the influence of catalyst particle size on the catalytic effect of H2O2 in heterogeneous catalytic reactions is not significant.

[0089] The present application shows through the two groups of results of Example 4, Comparative Example 4, Comparative Examples 10-13, Comparative Examples 18-19 and Comparative Example 9 and Comparative Example 20 that a suitable ratio is required in the methylene blue degradation test, otherwise flocculation will occur. For example, Comparative Example 18, Comparative Example 19 and Comparative Example 20 will produce methylene blue flocculation, and this phenomenon disappears after adjusting the appropriate reagent ratio.

[0090] In summary, the test method provided by the present invention overcomes the problems of methylene blue flocculation in conventional tests, complex test methods, long test time, and environmental pollution; the test method of the present invention can conveniently, quickly and accurately judge the catalytic performance of the catalyst.

[0091] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for green detection of catalytic performance of a high-efficiency catalyst, characterized in that: The method comprises the following steps: S1: preparing a catalyst-oxidant-methylene blue solution; S2: diluting the oxidant-catalyst-methylene blue solution obtained in step S1, and then testing the absorbance by a UV spectrophotometer; S3: Evaluate the catalytic oxidizing property of the catalyst in the solution based on the degradation rate of methylene blue.

2. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: In step S1, the oxidant is H2O2.

3. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: The concentration of the oxidant is 0.01-10 wt %; preferably, the concentration of the oxidant is 0.1-2 wt %.

4. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: The catalyst in step S1 contains one or more of the elements iron, copper, manganese, zinc, and vanadium, either as a single substance or as an element compound.

5. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: The catalyst concentration in step S1 is 0-1 mol / L, preferably, the catalyst concentration is 0-200 mmol / L.

6. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: In step S1, the concentration of methylene blue is 0.01 to 150,000 μmol / L.

7. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: The concentration of methylene blue in step S1 is 1-150000 μmol / L.

8. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: The oxidant-catalyst-methylene blue solution in step S2 is diluted by 0-10000 times, preferably, by 0-1000 times.

9. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: The test wavelength of the absorbance tested by the ultraviolet spectrophotometer in step S2 is 200-1000 nm, preferably, the test wavelength is 660 nm.

10. The method for green detection of catalytic performance of a high-efficiency catalyst according to claim 1, characterized in that: The catalytic oxidizing property of the catalyst in the solution was evaluated according to the degradation rate of methylene blue. The catalytic oxidizing property of the catalyst in the solution was positively correlated with the degradation rate of methylene blue.

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