Preparation method and application of activated peroxide Fenton-like water treatment catalyst

Abstract

The invention relates to a preparation method and application of an activated peroxide Fenton-like water treatment catalyst, and the preparation method comprises the following steps: S1, collecting naturally falling dead leaves, drying in a drying oven, and then calcining, grinding and sieving to obtain a precursor A; s2, humic acid and vitamin C are soaked in deionized water, and after water bath heating and stirring are conducted, steeping liquor B is obtained; s3, adding the precursor A and the steeping liquor B into an organic solvent, and heating and stirring in a water bath until the organic solvent is volatilized to obtain an intermediate C; s4, after the intermediate C is dried, calcining, washing, drying, grinding and sieving are sequentially conducted, and the activated peroxide Fenton-like water treatment catalyst is obtained. The catalyst can activate peroxide, generate free radicals, form a catalyst-peroxide catalytic purification system in sewage and remove organic pollutants in water, the efficiency is high, secondary pollution is avoided, the energy consumption is reduced, and the treatment efficiency is improved.

Description

Technical Field

[0001] The invention relates to the field of pollutant treatment, and in particular to a preparation method and application of an activated peroxide-type Fenton water treatment catalyst. Background Art

[0002] With the rapid development of industry and human society, the discharge of sewage is also increasing. Sewage contains harmful substances such as organic matter, inorganic salts, sulfides, nitrides and various heavy metals, which cause great pollution to the environment.

[0003] At present, the methods used by sewage treatment plants to treat new pollutants in water include adsorption using activated sludge and membrane bioreactor technology combined with traditional activated sludge method. However, after using the above methods to treat sewage containing POPs, new pollutants can still be detected in the effluent. Since traditional sewage treatment processes are difficult to adapt to the current status of water pollution, it is necessary to develop research on deep treatment of new pollutants in water.

[0004] Based on this, advanced oxidation technologies (AOPs) that can generate strong oxidative active species for tertiary sewage treatment have gradually developed. However, traditional advanced oxidation technologies have defects such as high pH range requirements, low selectivity, easy production of iron sludge, high treatment costs, and the need for continuous addition of reagents. Therefore, it is necessary to develop an efficient, low-energy, and clean water treatment technology. Summary of the invention

[0005] In view of the problems existing in the prior art, the purpose of the present invention is to provide a preparation method and application of an activated peroxide-type Fenton water treatment catalyst, which can activate peroxides to quickly treat pollutants in water, can adapt to a wider pH range, has a long service life, and consumes very little energy.

[0006] The purpose of the present invention is achieved by the following technical solutions:

[0007] In a first aspect, the present invention provides a method for preparing an activated peroxide-based Fenton water treatment catalyst, comprising the following steps:

[0008] S1: Collect naturally fallen dead leaves and dry them in an oven, then calcine, grind and sieve to obtain precursor A;

[0009] S2: Soaking humic acid and vitamin C in deionized water, heating in a water bath and stirring for a period of time to obtain an impregnation solution B;

[0010] S3: adding the precursor A and the impregnation solution B into an organic solvent, heating and stirring in a water bath until the organic solvent evaporates, to obtain an intermediate C;

[0011] S4: After drying the intermediate C, calcining, washing, drying, grinding and sieving are performed in sequence to obtain an activated peroxide-type Fenton water treatment catalyst.

[0012] Preferably, in S1, the drying temperature in the oven is 80-120° C., and the drying time is 5-15 hours.

[0013] Preferably, in S1, the calcination is performed by programmed temperature rise in a muffle furnace, the oxygen atmosphere is 20%-30%, the temperature in the first stage is 300-400°C, maintained for 2-3h, and the heating rate is 5-10°C / min; the temperature in the second stage is 600-700°C, maintained for 4-6h, and the heating rate is 5-10°C / min.

[0014] Preferably, in S1, the grinding and sieving are sieving through a 50-150 mesh sieve.

[0015] Preferably, in S2, the mass ratio of humic acid to vitamin C is (0-5) g: (1-4) g, and the volume of deionized water is 50-100 mL.

[0016] Preferably, in S2, the water bath temperature is 30-50°C, and the stirring speed is 500-800 rpm.

[0017] Preferably, in S3, the organic solvent is one of methanol, ethanol and isopropanol.

[0018] Preferably, in S3, the volume ratio of the mass of the precursor A to the impregnation liquid B is (10-20) g: (20-50) mL.

[0019] Preferably, in S3, the volume ratio of the mass of the precursor A to the organic solvent is (10-20) g: (100-250) mL.

[0020] Preferably, in S3, the water bath temperature is 60-100° C., and the stirring speed is 500-1000 rpm.

[0021] Preferably, in S4, the drying temperature of the intermediate C is 50-100° C., and the drying time is 5-10 h.

[0022] Preferably, in S4, a muffle furnace is used for programmed calcination, the oxygen atmosphere is 20%-30%, the temperature in the first stage is 300-400°C, maintained for 2-3h, and the heating rate is 5-10°C / min; the temperature in the second stage is 600-700°C, maintained for 4-6h, and the heating rate is 5-10°C / min.

[0023] Preferably, in S4, washing is performed by alternating ultrapure water and ethanol for 3-10 times; the drying temperature is 80-120° C., and the drying time is 5-15 hours; and grinding and sieving are performed by sieving through a 50-150 mesh sieve.

[0024] In a second aspect, the present invention provides an activated peroxide-based Fenton water treatment catalyst, which is prepared using the above-mentioned preparation method.

[0025] In a third aspect, the present invention provides an application of an activated peroxide-type Fenton water treatment catalyst in treating pollutants in water.

[0026] Preferably, the pollutants include, but are not limited to, rhodamine B (RhB), acid orange 7 (AO7), methylene blue (MB), ciprofloxacin (CIP), bisphenol A (BPA) and phenytoin (PHT).

[0027] Preferably, the concentration of pollutants in the water is 1-100 ppm; and the amount of the catalyst used when treating pollutants in the water is 0.1-2 g / L.

[0028] The beneficial effects of the present invention are:

[0029] 1. The catalyst of the present invention can activate peroxides, generate free radicals, and form a catalyst-peroxide catalytic purification system in sewage. In the process of removing organic pollutants in water, it is highly efficient and will not produce secondary pollution, thereby reducing energy consumption and improving treatment efficiency.

[0030] 2. The catalyst of the present invention can adapt to a wider pH range when treating organic pollutants in sewage and has strong applicability.

[0031] 3. The catalyst of the present invention is a solid powder catalyst, which has a long service life, is easy to separate and recycle sewage, can be recycled, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0033] Figure 1 This is a scanning electron microscope image of the catalyst prepared in Example 1;

[0034] Figure 2 The degradation curve of ciprofloxacin (CIP) activated by different amounts of peroxide prepared in Example 1;

[0035] Figure 3 Degradation curves of ciprofloxacin (CIP) by different amounts of catalyst activated peroxide prepared in Example 1;

[0036] Figure 4 The degradation curve of ciprofloxacin (CIP) by the catalyst prepared in Example 1 under different pH conditions;

[0037] Figure 5 This is a diagram showing the effect of the catalyst prepared in Example 1 on continuously treating COD in kitchen wastewater. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is described below through specific examples. It should be understood that the one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combination step or the insertion of other method steps between these explicitly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to limit the scope of the present invention. The change or adjustment of the relative relationship thereof shall also be regarded as the scope of the present invention without substantially changing the technical content.

[0039] In order to better understand the above technical scheme, the exemplary embodiments of the present invention are described in more detail below. Although exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0040] The present invention will be further described below in conjunction with the following examples.

[0041] Example 1

[0042] A method for preparing an activated peroxide-based Fenton water treatment catalyst comprises the following steps:

[0043] S1: Preparation of Precursor A

[0044] Collect naturally fallen dead leaves and dry them in an oven at 100℃ for 7h, and use a muffle furnace to program the calcination, with an oxygen atmosphere of 20%, the temperature of the first stage is 300℃, maintained for 2h, and the heating rate is 5℃ / min; the temperature of the second stage is 600℃, maintained for 6h, and the heating rate is 5℃ / min. Grind until it can pass through an 80-mesh screen to obtain precursor A;

[0045] S2: Preparation of impregnation solution B

[0046] Soak 2g of humic acid and 3g of vitamin C in 50mL of deionized water, heat in a water bath and stir for a period of time to obtain an impregnation solution B;

[0047] S3: Preparation of Intermediate C

[0048] Add 10 g of precursor A and 30 mL of impregnation solution B into 100 mL of methanol, heat in a constant temperature water bath at 80°C, and stir (at a speed of 600 rpm) until the organic solvent is completely evaporated to obtain intermediate C;

[0049] S4: Preparation of catalyst

[0050] After drying the intermediate C in a 60°C oven for 7 hours, the intermediate C was calcined in a muffle furnace with a 20% oxygen atmosphere, a temperature of 300°C in the first stage, maintained for 2 hours, and a heating rate of 5°C / min; the temperature of the second stage was 600°C, maintained for 6 hours, and a heating rate of 5°C / min. The intermediate C was washed alternately with ultrapure water and ethanol for 5 times, dried in an 80°C oven for 7 hours, and ground to pass through a 100-mesh sieve to obtain an activated peroxide Fenton water treatment catalyst (HAVC-1).

[0051] Example 2

[0052] A method for preparing an activated peroxide-based Fenton water treatment catalyst comprises the following steps:

[0053] S1: Preparation of Precursor A

[0054] Collect naturally fallen dead leaves and dry them in an oven at 80℃ for 15h, and use a muffle furnace to program the calcination, with an oxygen atmosphere of 25%, the temperature of the first stage is 350℃, maintained for 2.5h, and the heating rate is 5℃ / min; the temperature of the second stage is 650℃, maintained for 5h, and the heating rate is 5℃ / min. Grind until it can pass through a 50-mesh screen to obtain precursor A;

[0055] S2: Preparation of impregnation solution B

[0056] Soak 1g humic acid and 2g vitamin C in 50mL deionized water, heat in a water bath and stir for a period of time to obtain impregnation solution B;

[0057] S3: Preparation of Intermediate C

[0058] Add 12 g of precursor A and 25 mL of impregnation solution B into 100 mL of ethanol, heat in a constant temperature water bath at 90°C, and stir (at a speed of 700 rpm) until the organic solvent is completely evaporated to obtain intermediate C;

[0059] S4: Preparation of catalyst

[0060] After drying the intermediate C in a 70°C oven for 6 hours, the intermediate C was calcined in a muffle furnace with a 25% oxygen atmosphere. The temperature of the first stage was 350°C, maintained for 2 hours, and the heating rate was 5°C / min; the temperature of the second stage was 650°C, maintained for 6 hours, and the heating rate was 5°C / min. The intermediate C was washed alternately with ultrapure water and ethanol for 5 times, dried in a 90°C oven for 6 hours, and ground to pass through a 50-mesh sieve to obtain an activated peroxide Fenton water treatment catalyst (HAVC-2).

[0061] Example 3

[0062] A method for preparing an activated peroxide-based Fenton water treatment catalyst comprises the following steps:

[0063] S1: Preparation of Precursor A

[0064] Collect naturally fallen dead leaves and dry them in an oven at 120℃ for 5h, and use a muffle furnace to program the calcination, with an oxygen atmosphere of 30%, the temperature of the first stage is 400℃, maintained for 3h, and the heating rate is 5℃ / min; the temperature of the second stage is 700℃, maintained for 4h, and the heating rate is 5℃ / min. Grind until it can pass through a 150-mesh screen to obtain precursor A;

[0065] S2: Preparation of impregnation solution B

[0066] Soak 4g of humic acid and 2g of vitamin C in 100mL of deionized water, heat in a water bath and stir for a period of time to obtain an impregnation solution B;

[0067] S3: Preparation of Intermediate C

[0068] Add 20 g of precursor A and 50 mL of impregnation solution B into 200 mL of isopropanol, heat in a constant temperature water bath at 100°C, and stir (at a speed of 1000 rpm) until the organic solvent is completely evaporated to obtain intermediate C;

[0069] S4: Preparation of catalyst

[0070] After drying the intermediate C in an oven at 80°C for 8 hours, the intermediate C was calcined in a muffle furnace with a 30% oxygen atmosphere, a temperature of 400°C in the first stage, maintained for 3 hours, and a heating rate of 5°C / min; the temperature of the second stage was 700°C, maintained for 4 hours, and a heating rate of 5°C / min. The intermediate C was washed alternately with ultrapure water and ethanol for 5 times, dried in an oven at 120°C for 5 hours, and ground to pass through a 150-mesh sieve to obtain an activated peroxide Fenton water treatment catalyst (HAVC-3).

[0071] Application Example 1

[0072] The activated peroxide Fenton water treatment catalyst (HAVC-1) prepared in Example 1 was used to activate peroxymonosulfate to degrade ciprofloxacin; the details are as follows:

[0073] Take 3 portions of 0.01g of the catalyst (HAVC-1) of Example 1 and add them to 3 portions of 50mL, 10ppm ciprofloxacin solution, then add (1mM, 2mM, 5mM) permonosulfate, keep the temperature at 35°C, and stir (speed is 500rpm). Samples are taken at a certain time gradient to detect the change in pollutant concentration; the results are as follows Figure 2 shown.

[0074] Figure 2 The results showed that the removal rate of ciprofloxacin in the 5mM permonosulfate system reached more than 90% at 1 minute, and the removal rate of ciprofloxacin in the 2mM permonosulfate system reached about 90% at 10 minutes.

[0075] Application Example 2

[0076] The activated peroxide Fenton water treatment catalyst (HAVC-1) prepared in Example 1 was used to activate peroxymonosulfate to degrade ciprofloxacin; the details are as follows:

[0077] Three portions (0.005 g, 0.01 g, 0.02 g) of the catalyst (HAVC-1) of Example 1 were added to three portions of 50 mL, 10 ppm ciprofloxacin solutions, and then 2 mM permonosulfate was added, the temperature was kept at 35°C, and the stirring speed was 500 rpm. Samples were taken at a certain time gradient to detect the change in pollutant concentration; the results are as follows Figure 3 shown.

[0078] Figure 3 The results showed that the removal rate of ciprofloxacin in the 0.02g HAVC-1 system reached more than 90% at 1 min, and the removal rate of ciprofloxacin in the 0.01g HAVC-1 system reached more than 90% at 2 min.

[0079] Application Example 3

[0080] The activated peroxide Fenton water treatment catalyst (HAVC-1) prepared in Example 1 was used to activate peroxymonosulfate to degrade ciprofloxacin at different pH values; the details are as follows:

[0081] Take 5 portions of 0.01g of the catalyst (HAVC-1) of Example 1 and add them to 5 portions of 50mL, 10ppm ciprofloxacin solution (pH=3.02, 5.01, 7.02, 9.00, 11.00), respectively, and then add 2mM permonosulfate, keep the temperature at 35°C, and stir (speed is 500rpm). Samples are taken according to a certain time gradient to detect the change of pollutant concentration; the results are as follows Figure 4 shown.

[0082] Figure 4 The results showed that at 10 min, the removal rate of ciprofloxacin in the systems with pH = 5.01, 7.02, 9.00, and 11.00 reached about 99%; the removal rate of ciprofloxacin in the system with pH = 3.02 reached about 60%.

[0083] Application Example 4

[0084] The activated peroxide-type Fenton water treatment catalyst (HAVC-1) prepared in Example 1 was used to activate peroxymonosulfate to degrade kitchen wastewater; the details are as follows:

[0085] A fixed bed reactor was built and operated continuously under natural conditions. The hydraulic retention time was 20 minutes and the sampling interval was 1 day. The initial data and post-treatment data of COD in the kitchen wastewater were tested. The results are as follows: Figure 5 shown.

[0086] Figure 5 The results show that during the 15-day operation, the removal rate of COD in actual kitchen wastewater is maintained at about 40%, indicating that the catalyst (HAVC-1) of the present invention has good stability and can be applied to the treatment of actual wastewater.

[0087] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0088] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preparing an activated peroxide Fenton water treatment catalyst, characterized in that: The following steps are involved: S1: Collect naturally fallen dead leaves and dry them in an oven, then calcine, grind and sieve to obtain precursor A; S2: Soaking humic acid and vitamin C in deionized water, heating and stirring in a water bath to obtain an impregnation solution B; S3: adding the precursor A and the impregnation solution B into an organic solvent, heating and stirring in a water bath until the organic solvent evaporates, to obtain an intermediate C; S4: After drying the intermediate C, calcining, washing, drying, grinding and sieving are performed in sequence to obtain an activated peroxide-type Fenton water treatment catalyst.

2. The method for preparing an activated peroxide Fenton water treatment catalyst according to claim 1, characterized in that: In the S1, the drying temperature in the oven is 80-120°C, and the drying time is 5-15h; the grinding and sieving are sieved through a 50-150 mesh sieve; the calcination is performed using a muffle furnace programmed temperature calcination, the oxygen atmosphere is 20%-30%, the temperature in the first stage is 300-400°C, maintained for 2-3h, and the heating rate is 5-10°C / min; the temperature in the second stage is 600-700°C, maintained for 4-6h, and the heating rate is 5-10°C / min.

3. The method for preparing an activated peroxide Fenton water treatment catalyst according to claim 1, characterized in that: In S2, the mass ratio of humic acid to vitamin C is (0-5) g:(1-4) g, and the volume of deionized water is 50-100 mL.

4. The method for preparing an activated peroxide Fenton water treatment catalyst according to claim 1, characterized in that: In S2, the water bath temperature is 30-50°C, and the stirring speed is 500-800 rpm.

5. The method for preparing an activated peroxide Fenton water treatment catalyst according to claim 1, characterized in that: In S3, the volume ratio of the mass of the precursor A to the impregnation liquid B is (10-20) g: (20-50) mL; the volume ratio of the mass of the precursor A to the organic solvent is (10-20) g: (100-250) mL.

6. The method for preparing an activated peroxide Fenton water treatment catalyst according to claim 1, characterized in that: In S3, the water bath temperature is 60-100° C., and the stirring speed is 500-1000 rpm.

7. The method for preparing an activated peroxide-based Fenton water treatment catalyst according to claim 1, characterized in that: In the S4, the drying temperature of the intermediate C is 50-100°C, and the drying time is 5-10h; a muffle furnace is used for programmed temperature calcination, the oxygen atmosphere is 20%-30%, the temperature of the first stage is 300-400°C, maintained for 2-3h, and the heating rate is 5-10°C / min; the temperature of the second stage is 600-700°C, maintained for 4-6h, and the heating rate is 5-10°C / min; washing is performed alternately with ultrapure water and ethanol for 3-10 times; the drying temperature is 80-120°C, and the drying time is 5-15h; grinding and sieving are performed through a 50-150 mesh sieve.

8. An activated peroxide Fenton water treatment catalyst, characterized in that: The preparation method according to claim 1 is used for preparation.

9. Use of the activated peroxide Fenton water treatment catalyst according to claim 8 in treating pollutants in water.

10. Use of the activated peroxide Fenton water treatment catalyst according to claim 9 in treating pollutants in water, characterized in that: The pollutant is at least one of rhodamine B, acid orange 7, methylene blue, ciprofloxacin, bisphenol A and phenytoin.

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