A renewable catalyst and its preparation method

Abstract

The present application discloses a renewable catalyst. The present invention relates to a preparation method of a novel self-regenerating perovskite material and a perovskite material doped with multiple metal elements and its application in catalytic ozone degradation of pollutants. This material exhibits extremely excellent catalytic oxidation performance in the catalytic ozone oxidation system, greatly improving the degradation effect of pollutants. At the same time, this material can achieve self-regeneration through simple redox heat treatment, solving problems such as easy agglomeration of active components of the catalyst and deactivation of the catalyst due to carbon deposition on the surface, and the catalyst can still maintain good catalytic activity after regeneration, effectively improving the recycling utilization rate of the catalyst.

Description

Technical Field

[0001] The present application relates to a renewable catalyst and a preparation method thereof, belonging to the field of environmental functional materials. Background Art

[0002] With the development of the economy and the improvement of the industrialization level, while the water demand is increasing continuously, a large amount of industrial wastewater is also generated, leading to more serious water pollution and further exacerbating the problem of water resource shortage. Especially the wastewater generated in the process of chemical processing and manufacturing is not only large in quantity but also complex in composition, containing a large number of toxic organic pollutants, which has become the focus of current wastewater research. How to remove the refractory organic pollutants in wastewater has become the key point and difficulty in current wastewater treatment. Advanced oxidation processes (AOPs) can effectively remove organic pollutants in wastewater through oxidation degradation means and have been widely used. Among them, the catalytic ozonation technology can generate a large number of oxidizing substances (such as hydroxyl radicals (·OH)) through the joint action of a catalyst and ozone. Compared with ordinary ozonation, it can greatly improve the wastewater treatment efficiency.

[0003] In the ozone catalytic oxidation reaction system, selecting a high-performance catalyst is the key point. The catalytic ozonation catalysts are divided into homogeneous and heterogeneous ones. Among them, the heterogeneous catalytic ozonation catalysts are more conducive to separation and recovery and are more widely used in the field of wastewater treatment. The currently commonly used heterogeneous catalytic ozonation catalysts are mainly supported catalysts, which are composed of active components and carriers. The active components mainly include oxides of noble metals, transition metals (Fe, Mn, Co), and rare earth elements (La, Ce), etc., and the carriers mainly include A12O3, activated carbon, ceramic-based materials, etc. Through the action of the catalyst, ozone can effectively decompose and mineralize organic pollutants to achieve the treatment purpose. However, in the current applications, there are still certain problems, such as the active components of the catalyst are prone to agglomeration and carbon deposition on the surface, resulting in catalyst deactivation, and the loss of components causes secondary pollution, etc.

[0004] Compared with ordinary transition metal oxides, perovskite-type composite metal oxides have a higher lattice oxygen migration rate and redox ability, and can also be modified by adjusting different element components. Among them, zirconium (Zr)-based perovskite materials, such as zirconia (ZrO2), have been widely used at present. ZrO2 has the characteristics of high temperature resistance, corrosion resistance, and photothermal stability. Strontium zirconate perovskite-type materials have a typical ABO3 perovskite structure, with good chemical stability and mechanical properties. The B-site element, as the center of the perovskite crystal structure, affects the catalytic activity and structural stability of the catalyst. However, it is found in actual applications that there are still phenomena such as agglomeration and carbon deposition on the catalyst surface, and it is difficult to regenerate. In the present invention, Fe and Mn are doped at the B-site on the basis of strontium zirconate to make the active components easy to regenerate and realize the cyclic application of the catalyst. Summary of the Invention

[0005] To solve the above problems, according to one aspect of the present application, a renewable catalyst material is provided. This material exhibits excellent catalytic oxidation performance in the catalytic ozone oxidation system, improving the pollutant degradation ability. At the same time, this material can achieve self-regeneration through simple redox heat treatment, solving problems such as easy agglomeration of the active components of the catalyst and carbon deposition on the surface resulting in catalyst deactivation. Moreover, the catalyst can still maintain good catalytic activity after regeneration, effectively improving the recycling utilization rate of the catalyst. The technical solution of the present invention is as follows:

[0006] A renewable catalyst, wherein the renewable catalyst has a perovskite structure; the renewable catalyst is selected from any one of the compounds having the chemical formula shown in Formula I;

[0007] SrMn (x) Fe (1-x) ZrO3 Formula I;

[0008] In Formula I, the value range of x is 0 ≤ x ≤ 1.

[0009] Specifically, the renewable catalyst has the function of catalytic ozone oxidation.

[0010] Specifically, the catalyst provided by the present application is an intelligent regenerable catalyst. The metal components doped in the catalyst (such as Fe, Mn, Co) can dissolve (in a high-temperature oxidation atmosphere) / dissolve out (in a high-temperature reduction atmosphere) inside and on the surface of the perovskite lattice. This process is reversible, thereby improving the agglomeration of the active component particles and solving the problem of surface carbon deposition, and enabling the catalyst to maintain good catalytic activity.

[0011] Optionally, the value range of x is 0.4 ≤ x ≤ 0.9;

[0012] Optionally, x is 0.5.

[0013] The preparation method of the renewable catalyst includes:

[0014] Step 1: Respectively obtain a composite solution A containing Sr source, Mn source, Fe source and Zr source and a precipitant dispersion solution B, and mix them to obtain a colloidal solution;

[0015] Step 2: Age, filter with suction and wash the colloidal solution obtained in Step 1 to obtain a precipitate;

[0016] Step 3: Dry the precipitate and then calcine it to obtain the renewable catalyst;

[0017] Optionally, the Sr source is selected from at least one of SrCl2, Sr(NO3)2 and Sr(OH)2.

[0018] Optionally, the Fe source is selected from at least one of FeCl3 and Fe(NO3)2.

[0019] Optionally, the Mn source is selected from at least one of MnCl2 and Mn(NO3)2.

[0020] Optionally, the Zr source is selected from at least one of ZrOCl·8H2O and ZrCl4.

[0021] Optionally, during the mixing process, the dosages of the components can be proportioned according to the stoichiometric ratio shown in Formula I.

[0022] Optionally, in the composite solution A, the concentration of the Sr source is 0.1 - 0.4 mol / L; the total concentration of the Fe source and the Mn source is 0.01 - 0.2 mol / L; the concentration of the Zr source is 0.05 - 0.2 mol / L.

[0023] In a specific example, in the mixed solution, the concentrations of the Sr salt, the Fe salt, the Mn salt, and the Zr salt are 0.11 mol / L, x mol / L, (0.1 - x) mol / L, and 0.1 mol / L respectively; x = 0 - 0.1.

[0024] The precipitant dispersion is an aqueous solution containing oxalic acid, ammonia water, and a dispersant;

[0025] Preferably, the dispersant includes any one of polyethylene glycol and sodium dodecyl sulfate;

[0026] Optionally, the concentration of oxalic acid in the precipitant dispersion is 0.5 - 5 mol / L;

[0027] The concentration of ammonia water in the precipitant dispersion is 0.1 - 5 mol / L;

[0028] The concentration of the dispersant in the precipitant dispersion is 1 - 8 g / L;

[0029] Optionally, after mixing the composite solution A and the precipitant dispersion solution B in Step 1, the pH is adjusted to 8 - 10 with ammonia water;

[0030] Optionally, after the solutions are mixed in Step 1, they are stirred, and the stirring speed is 100 - 800 r / min, and the stirring time is 1 - 2 h;

[0031] Optionally, the conditions for aging in Step 2 are: the aging time is 4 - 30 hours, and the aging temperature is 40 - 200 °C;

[0032] Specifically, the upper limit of the aging time is selected from any one of 8 h, 12 h, 16 h, 20 h, 24 h, and 28 h; the lower limit of the aging time is selected from any one of 8 h, 12 h, 16 h, 20 h, 24 h, and 28 h.

[0033] The upper limit of the aging temperature is selected from any one of 80 °C, 100 °C, 120 °C, 140 °C, and 160 °C; the lower limit of the aging temperature is selected from any one of 60 °C, 80 °C, 100 °C, 120 °C, and 140 °C.

[0034] Optionally, after suction filtration in step two, the sample is washed with deionized water or absolute ethanol 2 - 5 times, with a dosage of 100 - 300 mL each time;

[0035] Optionally, the drying conditions in step three are: the drying temperature is 80 - 120 °C, and the drying time is 8 - 14 h;

[0036] Specifically, the upper limit of the drying temperature is selected from any one of 90 °C, 100 °C, 110 °C, and 120 °C; the lower limit of the drying temperature is selected from any one of 80 °C, 90 °C, 100 °C, and 110 °C.

[0037] The upper limit of the drying time is selected from any one of 10 h, 12 h, and 14 h; the lower limit of the drying time is selected from any one of 8 h, 9 h, and 10 h.

[0038] Optionally, the calcination conditions in step three are: the calcination temperature is 400 - 1200 °C, and the calcination time is 1 - 8 h;

[0039] Specifically, the upper limit of the calcination temperature is selected from any one of 800 °C, 900 °C, 1000 °C, 1100 °C, and 1200 °C; the lower limit of the calcination temperature is selected from any one of 700 °C, 800 °C, 900 °C, 1000 °C, and 1100 °C.

[0040] The upper limit of the calcination time is selected from any one of 4 h, 6 h, and 8 h; the lower limit of the calcination time is selected from any one of 1 h, 3 h, and 5 h.

[0041] Optionally, after calcining to obtain the renewable catalyst, it further includes performing a reduction treatment on the renewable catalyst;

[0042] Optionally, the reduction includes: reducing for 2 - 8 h under the condition of 400 - 1000 °C in a reducing gas with a flow rate of 10 - 250 mL / min;

[0043] Specifically, the reducing gas can be any one of H2 and CO.

[0044] The upper limit of the flow rate of the reducing gas is selected from any one of 50 mL / min, 100 mL / min, and 200 mL / min; the lower limit of the flow rate of the reducing gas is selected from any one of 10 mL / min, 50 mL / min, and 100 mL / min.

[0045] The upper limit of the reduction temperature is selected from 500 °C, 800 °C, and 1000 °C; the lower limit of the reduction temperature is selected from 400 °C, 700 °C, and 900 °C.

[0046] The upper limit of the reduction time is selected from 5 h, 6 h, 7 h, and 8 h; the lower limit of the reduction time is selected from 2 h, 3 h, 4 h, and 5 h.

[0047] A method for regenerating a catalyst, characterized in that the deactivated catalyst is first subjected to high-temperature oxidation treatment to smooth the catalyst surface, and then subjected to high-temperature reduction treatment to precipitate the surface particles of the catalyst, obtaining a regenerated catalyst.

[0048] The catalyst includes any one of the renewable catalysts described in any of the above items, the renewable catalysts obtained by the preparation method described in any of the above items, and the regenerated catalysts obtained by the regeneration method described in any of the above items.

[0049] Optionally, the conditions for the high-temperature oxidation treatment are: the oxygen flow rate is 5-250 mL / min, the oxidation temperature is 400-1000 °C, and the oxidation time is 1-6 h.

[0050] Optionally, the conditions for the high-temperature reduction treatment are: the hydrogen flow rate is 5-250 mL / min, the temperature is 400-1000 °C, and the reduction time is 1-6 h.

[0051] The perovskite-type catalyst SrMn (x) Fe (1-x) ZrO3 prepared by the preparation method according to the above item is used in the catalytic ozonation, and the catalyst is used for catalytic ozonation treatment of various refractory biodegradable industrial organic wastewater.

[0052] Optionally, the degradation process is intermittent, and the reaction conditions are: the catalyst dosage: 0.5-10 g / L, the initial pH of the pollutant solution: 2-10, the reaction temperature: 10-50 °C, the ozone flow rate: 10-160 mL / min, the ozone concentration: 50-200 mg / L, and the stirring speed: 100-600 r / min.

[0053] Optionally, the pollutants in the wastewater are organic pollutants.

[0054] Optionally, the pollutants in the wastewater include any one of m-cresol, p-phenol, bisphenol A, etc.

[0055] The following presents a specific preparation method of a renewable catalyst, and a perovskite intelligent regeneration SrMn is prepared by the co-precipitation method (x) Fe (1-x) ZrO3 catalyst, including the following steps:

[0056] a) Add the composite salt solution A to the precipitant dispersion solution B, mix and stir evenly to obtain a white colloidal solution;

[0057] b) Age, filter by suction and wash the white colloidal solution to obtain a white precipitate;

[0058] c) Dry the precipitate to obtain a dried sample, and calcine the dried sample. The sample after calcination is the intelligent catalyst;

[0059] d) High-temperature reduce the intelligent catalyst to activate the catalyst.

[0060] Optionally, the composite salt solution is 0.18 mol SrCl2·6H2O, 0.16 mol ZrOCl·8H2O, x mol MnCl2, and (1 - x) mol FeCl3·6H2O dissolved in 1 L of aqueous solution, and rapidly stirred for 1 - 2 h, where x = 0 - 0.2.

[0061] Optionally, the preparation method of the precipitation dispersion solution is: Add 0.19 mol of (NH4)2C2O4, 43 ml of 25 wt% ammonia water, and 7.6 g of polyethylene glycol (20000) to 1 L of deionized water, and rapidly stir and mix evenly.

[0062] Optionally, in step b), the aging time is 4 - 30 hours, and the aging temperature is 40 - 200 °C.

[0063] Optionally, in step c), the drying is carried out by vacuum drying, the drying temperature is 40 - 120 °C, and the drying time is 12 h.

[0064] Optionally, in step c), the calcination temperature is 400 - 1200 °C, and the calcination time is 1 - 4 h.

[0065] Optionally, in step d), for the catalyst activation, the hydrogen flow rate is 10 - 250 mL / min mL / min, the reduction temperature is 400 - 1000 °C, and the reduction time is 2 - 8 h.

[0066] A regeneration strategy for a novel intelligent regenerable catalyst. For the deactivated SrMn (x) Fe (1-x) ZrO3 catalyst, it is regenerated by high-temperature oxidation and high-temperature reduction methods. The main steps are to first perform high-temperature oxidation on the deactivated catalyst and then perform high-temperature reduction.

[0067] Optionally, for the high-temperature oxidation, the oxygen flow rate is 5 - 250 mL / min, the oxidation temperature is 400 - 1000 °C, and the oxidation time is 1 - 6 h.

[0068] Optionally, for the high-temperature reduction, the hydrogen flow rate is 5-250 mL / min, the temperature is 400-1000 °C, and the reduction time is 1-6 h.

[0069] The intelligent regeneration SrMn (x) Fe (1-x) ZrO3 catalyst prepared according to any one of the above preparation methods and regeneration strategies is applied in catalytic ozonation to treat refractory organic wastewater.

[0070] Optionally, the intermittent reaction conditions are as follows: catalyst dosage: 0.5-10 g / L, initial pH of the pollutant solution: 2-10, reaction temperature: 10-50 °C, ozone flow rate: 10-160 mL / min, ozone concentration: 50-200 mg / L, stirring speed: 100-600 r / min.

[0071] Optionally, the continuous reaction conditions are as follows: catalyst dosage: 5-20 g, initial pH of the solution: 2-10, reaction temperature: 10-50 °C, ozone flow rate: 10-160 mL / min, ozone concentration: 50-200 mg / L.

[0072] The method of the present application can achieve the following beneficial effects

[0073] 1) The renewable catalyst provided by the present application is a perovskite-type material SrMn (x) Fe (1-x) ZrO3, and its components are easy to regulate.

[0074] 2) The preparation method of the renewable catalyst provided by the present application is simple and feasible.

[0075] 3) The regeneration method of the renewable catalyst provided by the present application can be realized by using simple oxidation-reduction heat treatment.

[0076] 4) The catalyst synthesized by the present application has the ability of catalytic ozonation and can achieve rapid and efficient degradation of pollutants. Description of the Drawings

[0077] Figure 1 is a flow diagram of the preparation and application of the renewable catalyst;

[0078] Figure 2 is a diagram of the catalytic ozonation device;

[0079] Figure 3 Scanning electron microscope image of the synthesized intelligent catalyst SrMnFeZrO3. Detailed Embodiments

[0080] The following describes the present application in detail with reference to the embodiments, but the present application is not limited to these embodiments.

[0081] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0082] Here are some possible implementations:

[0083] Example 1

[0084] A perovskite intelligent regeneration catalyst is prepared by the following method:

[0085] Dissolve 0.18 mol SrCl2·6H2O, 0.16 mol ZrOCl·8H2O, and 0.1 mol FeCl3·6H2O in 1 liter of aqueous solution and stir rapidly for 60 min to obtain a mixed solution;

[0086] Add 0.19 mol of (NH4)2C2O4, 43 ml of 25 wt% ammonia water, and 7.6 g of polyethylene glycol (20000) into 1 L of deionized water, and stir quickly to mix well to obtain a precipitant dispersion;

[0087] Mixing the mixed solution A and the precipitant dispersion B to obtain a white colloidal solution;

[0088] The white colloidal solution was aged at 120°C for 20 h, filtered and washed to obtain a white precipitate.

[0089] The precipitate is dried at 120° C. for 12 hours to obtain a dry sample, and the dry sample is calcined at 1000° C. for 4 hours. The calcined sample is the smart catalyst precursor;

[0090] The smart catalyst precursor was activated with a hydrogen flow rate of 200 mL / min, a reduction temperature of 600°C, and a reduction time of 6 h to obtain a perovskite-type regenerable catalyst, which was recorded as sample 1#.

[0091] In sample 1#, the molar ratio of iron to manganese is 1:0, and the catalyst SrFeZrO3 is prepared.

[0092] Application of a perovskite-type regenerable catalyst: used for catalytic ozone oxidation degradation of organic wastewater.

[0093] A method for applying a perovskite-type regenerable catalyst is as follows:

[0094] Using a laboratory-made catalytic ozone oxidation device such as Figure 2 The device passes oxygen through an ozone generator, a control valve, a display, and a catalytic reactor in sequence, treats the meta-cresol model wastewater in the catalytic reactor, and finally discharges the tail gas from the catalytic reactor.

[0095] 200mL of 100mg / L m-cresol model wastewater (initial pH 6.5) was added to the reactor. No catalyst was added to the control group, and the catalyst was added to the experimental group, with the catalyst addition amount of 0.5g / L. Ozone was continuously introduced at a concentration of 40mg / L, a flow rate of 130mL / min, and a stirring speed of 600r / min. The reaction was stopped after 20min at 25℃, and the water quality indicators of the effluent were analyzed and shown in Table 1.

[0096] Table 1

[0097]

[0098] The m-cresol model wastewater in the present application refers to a solution in which m-cresol is dissolved in water to form a concentration of 100 mg / L.

[0099] Example 2

[0100] A double perovskite intelligent regeneration catalyst is prepared by the following method: the difference from Example 1 is

[0101] Replace "0.1 mol FeCl3·6H2O" with "0.08 mol FeCl3·6H2O, 0.02 mol MnCl2";

[0102] The stirring time "60min" is replaced by "80min";

[0103] The aging condition "20h, 120℃" is replaced by "24h, 100℃"

[0104] Calcination conditions "1000℃, 4h" replaced by "1100℃, 2h"

[0105] The activation treatment conditions "hydrogen flow rate is 200 mL / min, reduction temperature is 600 °C, and reduction time is 6 h" were replaced with "hydrogen flow rate is 100 mL / min, reduction temperature is 800 °C, and reduction time is 4 h";

[0106] The perovskite-type regenerable catalyst was obtained and recorded as sample 2#

[0107] In sample 2#, the molar ratio of iron to manganese is 8:2, and the catalyst SrFe 0.8 Mn 0.2 ZrO3.

[0108] Application of a perovskite-type regenerable catalyst: used for catalytic ozone oxidation degradation of organic wastewater.

[0109] A method for applying a perovskite-type regenerable catalyst is as follows:

[0110] Using a laboratory-made catalytic ozone oxidation device such as Figure 2, 200 mL of m-cresol model wastewater with a concentration of 100 mg / L (initial pH = 6.5) was added respectively. No catalyst was added to the control group, while a catalyst was added to the experimental group, and the catalyst dosage was 0.5 g / L. Ozone was continuously introduced at a concentration of 40 mg / L and a flow rate of 130 mL / min, and the stirring speed was 600 r / min. The reaction was stopped after 20 min at 25 °C, and the water quality indexes of the effluent were analyzed as shown in Table 2.

[0111] Table 2

[0112]

[0113] Example 3:

[0114] A perovskite-type renewable catalyst was prepared by the following method:

[0115] The difference from Example 1 is that:

[0116] "0.1 mol FeCl3·6H2O" was replaced with "0.05 mol FeCl3·6H2O, 0.05 mol MnCl2";

[0117] The aging conditions "20 h, 120 °C" were replaced with "16 h, 140 °C"

[0118] The calcination conditions "1000 °C, 4 h" were replaced with "900 °C, 6 h"

[0119] The activation treatment conditions "hydrogen flow rate of 200 mL / min, reduction temperature of 600 °C, reduction time of 6 h" were replaced with "hydrogen flow rate of 150 mL / min, reduction temperature of 500 °C, reduction time of 8 h";

[0120] A perovskite-type renewable catalyst was obtained and denoted as Sample 3#

[0121] In Sample 3#, the molar ratio of iron to manganese is 5:5, and the catalyst SrFe 0.5 Mn 0.5 ZrO3 was prepared.

[0122] An application of a perovskite-type renewable catalyst: for catalytic ozonation degradation of organic wastewater.

[0123] A method for applying a perovskite-type renewable catalyst is as follows:

[0124] Using a self-made catalytic ozonation device in the laboratory as Figure 2, 200 mL of m-cresol model wastewater with a concentration of 100 mg / L (initial pH = 6.5) was added respectively. No catalyst was added to the control group, while a catalyst was added to the experimental group, and the catalyst dosage was 0.5 g / L. Ozone was continuously introduced at a concentration of 40 mg / L and a flow rate of 130 mL / min, and the stirring speed was 600 r / min. The reaction was stopped after 20 min at 25 °C, and the water quality indexes of the effluent were analyzed as shown in Table 3.

[0125] Table 3

[0126]

[0127] Example 4:

[0128] A perovskite-type renewable catalyst was prepared by the following method:

[0129] The difference from Example 1 is that:

[0130] "0.1 mol FeCl3·6H2O" was replaced with "0.02 mol FeCl3·6H2O, 0.08 mol MnCl2";

[0131] The aging conditions "20 h, 120 °C" were replaced with "12 h, 160 °C"

[0132] The calcination conditions "1000 °C, 4 h" were replaced with "1200 °C, 2 h"

[0133] The activation treatment conditions "hydrogen flow rate of 200 mL / min, reduction temperature of 600 °C, reduction time of 6 h" were replaced with "hydrogen flow rate of 150 mL / min, reduction temperature of 1000 °C, reduction time of 4 h";

[0134] A perovskite-type renewable catalyst was obtained, denoted as Sample 4#

[0135] In Sample 4#, the molar ratio of iron to manganese is 2:8, and the catalyst SrFe 0.2 Mn 0.8 ZrO3 was prepared.

[0136] Application of a perovskite-type renewable catalyst: for catalytic ozonation degradation of organic wastewater.

[0137] The application method of a perovskite-type renewable catalyst is as follows:

[0138] Using a self-made catalytic ozonation device in the laboratory as Figure 2, 200 mL of m-cresol model wastewater with a concentration of 100 mg / L (initial pH = 6.5) was added respectively. The control group did not add a catalyst, while the experimental group added a catalyst with an addition amount of 0.5 g / L. Ozone was continuously introduced at a concentration of 40 mg / L and a flow rate of 130 mL / min, and the stirring speed was 600 r / min. The reaction was stopped after 20 min at 25 °C, and the water quality indexes of the effluent were analyzed as shown in Table 4.

[0139] Table 4

[0140]

[0141] Example 5:

[0142] A perovskite-type renewable catalyst was prepared by the following method:

[0143] The difference from Example 1 is that:

[0144] "0.1 mol FeCl3·6H2O" was replaced with "0.1 mol MnCl2";

[0145] The aging conditions "20 h, 120 °C" were replaced with "28 h, 80 °C"

[0146] The calcination conditions "1000 °C, 4 h" were replaced with "800 °C, 8 h"

[0147] The activation treatment conditions "hydrogen flow rate of 200 mL / min, reduction temperature of 600 °C, reduction time of 6 h" were replaced with "hydrogen flow rate of 50 mL / min, reduction temperature of 800 °C, reduction time of 4 h";

[0148] The perovskite-type renewable catalyst was obtained, denoted as Sample 5#

[0149] In Sample 5#, the molar ratio of iron to manganese was 0:1, and the catalyst SrMnZrO3 was prepared.

[0150] An application of a perovskite-type renewable catalyst: for catalytic ozonation degradation of organic wastewater.

[0151] A method for applying a perovskite-type renewable catalyst is as follows:

[0152] Using a self-made catalytic ozonation device in the laboratory as Figure 2, 200 mL of m-cresol model wastewater with a concentration of 100 mg / L (initial pH = 6.5) was added respectively. No catalyst was added to the control group, while a catalyst was added to the experimental group, with the catalyst dosage of 0.5 g / L. Ozone was continuously introduced at a concentration of 40 mg / L and a flow rate of 130 mL / min, and the stirring speed was 600 r / min. The reaction was stopped after 20 min at 25 °C, and the water quality indexes of the effluent were analyzed as shown in Table 5.

[0153] Table 5

[0154]

[0155] Morphology Test of Example 6

[0156] The morphology of Samples 1# - 5# was tested respectively using the FEI Quanta200F instrument. The test results showed that:

[0157] All the renewable catalysts in this application showed the morphological characteristics of a large number of nanoparticles distributed on the surface.

[0158] Taking Sample 2# as a typical representative, Figure 3 For the synthetic intelligent catalyst SrFe 0.8 Mn 0.2 ZrO3 in Example 2, the scanning electron microscope image shows that Figure 3 the surface of the sample is flat and the particles are evenly distributed.

[0159] The above are only several embodiments of this application, and do not impose any form of limitation on this application. Although this application is disclosed with preferred embodiments as above, it is not intended to limit this application. Any person skilled in the relevant art can make some changes or modifications within the scope of the technical solution of this application using the disclosed technical content, which are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

Claims

1. A method for degrading pollutants, characterized in that, The method includes: degrading pollutants in an ozone atmosphere using a renewable catalyst; The reaction process is intermittent, and the reaction conditions are: catalyst dosage: 0.5 g / L, initial pH of the pollutant solution: 2 - 10, reaction temperature: 10 - 50 °C, ozone flow rate: 10 - 160 mL / min, ozone concentration: 50 - 200 mg / L, stirring speed: 100 - 600 r / min; The renewable method of the renewable catalyst includes: first performing high-temperature oxidation treatment on the deactivated catalyst to make the catalyst surface smooth, and then performing high-temperature reduction treatment to dissolve the surface particles of the catalyst to obtain the regenerated renewable catalyst; The renewable catalyst has a perovskite structure; the renewable catalyst is selected from SrFe 0.8 Mn 0.2 ZrO3, SrFe 0.5 Mn 0.5 ZrO3, SrFe 0.2 Mn 0.8 any one of the compounds with the chemical formula of ZrO3 The preparation method of the renewable catalyst includes: Step 1: Respectively obtain a composite solution A containing Sr source, Mn source, Fe source and Zr source and a precipitant dispersion solution B, and mix them to obtain a colloidal solution; Step 2: Age, filter and wash the colloidal solution obtained in Step 1 to obtain a precipitate; Step 3: Dry the precipitate and then calcine it to obtain the renewable catalyst. After calcining to obtain the renewable catalyst, a reduction treatment is also included for the renewable catalyst.

2. The method for degrading pollutants according to claim 1, wherein The precipitant dispersion solution B is an aqueous solution containing oxalic acid, ammonia water and a dispersant.

3. The method for degrading pollutants according to claim 2, characterized in that The dispersant includes any one of polyethylene glycol and sodium dodecyl sulfate.

4. The method for degrading pollutants according to claim 2, characterized in that The concentration of oxalic acid in the precipitant dispersion solution B is 0.5 - 5 mol / L; The concentration of ammonia water in the precipitant dispersion solution B is 0.1 - 5 mol / L; The concentration of the dispersant in the precipitant dispersion solution B is 1 - 8 g / L.

5. The method for degrading pollutants according to claim 1, characterized in that, In Step 1, after mixing the composite solution A and the precipitant dispersion solution B, the pH is adjusted to 8 - 10 with ammonia water.

6. The method for degrading pollutants according to claim 1, wherein, The conditions for aging in Step 2 are: aging time 4 - 30 hours, aging temperature 40 - 200 °C.

7. The method for degrading pollutants according to claim 1, characterized in that, The drying conditions in Step 3 are: drying temperature is 80 - 120 °C, drying time is 8 - 14 h.

8. The method for degrading pollutants according to claim 1, characterized in that, The calcination conditions in Step 3 are: calcination temperature 400 - 1200 °C, calcination time 1 - 8 h.

9. The method for degrading pollutants according to claim 1, wherein In Step 3, the reduction in the reduction treatment of the renewable catalyst includes: reducing in a reducing gas with a flow rate of 10 - 250 mL / min at 400 - 1000 °C for a reduction time of 2 - 8 h.

10. The method for degrading pollutants according to claim 1, characterized in that, The conditions for the high-temperature oxidation treatment are: oxygen flow rate is 5 - 250 mL / min, oxidation temperature is 400 - 1000 °C, oxidation time is 1 - 6 h.

11. The method for degrading pollutants according to claim 1, characterized in that, The conditions for the high-temperature reduction treatment are: hydrogen flow rate is 5 - 250 mL / min, temperature is 400 - 1000 °C, reduction time is 1 - 6 h.

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