A ruthenium-modified nickel-iron layered double hydroxide catalytic material and a method of making the same
By loading ruthenium onto NiFe-LDH to form Ru/NiFe-LDH catalytic material, the problem of insufficient activity of LDHs in PMS degradation reaction was solved, and efficient degradation of organic pollutants was achieved.
Patent Information
- Application Number
- CN202310792220.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-30
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2043-06-30
AI Technical Summary
Layered double hydroxides (LDHs) lack highly active catalytic centers in PMS-based advanced oxidative degradation reactions, resulting in low degradation efficiency for organic pollutants.
By loading ruthenium onto a NiFe-LDH support to form a Ru/NiFe-LDH catalytic material, and treating hydrated ruthenium chloride with an alkaline solution, the dispersion and utilization efficiency of ruthenium on NiFe-LDH are improved, forming a highly active catalytic center.
It significantly improved the activation ability of the catalytic material for PMS, and achieved efficient degradation of the organic pollutant atrazine, with a degradation rate of up to 100%.
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Figure CN116870929B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a ruthenium-modified nickel-iron layered double hydroxide catalytic material, and a preparation method of the catalytic material. BACKGROUND
[0002] In recent years, with the rapid development of urbanization and industrialization, the problem caused by organic pollutants is becoming increasingly serious due to the abuse of drugs and the extensive use of chemicals in daily activities. The types of organic pollutants are diversified, and the large amount of these pollutants discharged into the atmosphere, water bodies and soil pose a serious threat to the survival of animals and plants, and directly or indirectly affect human health and the ecological environment. Although adsorption, filtration, biodegradation and chemical degradation methods can remove pollutants in wastewater to some extent, these methods have the disadvantages of low efficiency, high cost and serious secondary pollution. Advanced oxidation technology (AOPs) can generate active species (hydroxyl radicals, sulfate radicals and singlet oxygen) with super-oxidation ability, which can achieve complete mineralization or decomposition of organic pollutants, and thus is widely used for degrading organic pollutants.
[0003] Layered double hydroxides (LDHs), also known as hydrotalcite-like clays or anionic clays, are widely favored in the fields of energy and environment due to their low cost, simple preparation, multiple chemical functions and good thermal stability. However, LDHs themselves often have no activity or very low activity in PMS-based advanced oxidation degradation reactions, mainly because of the lack of high-activity catalytic centers. SUMMARY
[0004] The present application aims to provide a ruthenium-modified nickel-iron layered double hydroxide catalytic material, which can effectively activate PMS, dissociate the O-O bond in PMS, and generate active species with strong oxidizing ability, thereby efficiently degrading organic pollutants. Another purpose of the present application is to provide a preparation method of the catalytic material.
[0005] The ruthenium-modified nickel-iron layered double hydroxide catalytic material according to the present application uses NiFe-LDH (layered double hydroxide composed of a large number of nanosheets stacked together, each layer being a two-dimensional sheet structure) in a sheet-like stacked structure as a carrier, and ruthenium is fixed on the NiFe-LDH carrier through oxygen atom coupling.
[0006] The loading amount of ruthenium on the NiFe-LDH carrier is 2.7-6.9% of the mass of the catalytic material.
[0007] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material includes the following steps:
[0008] (1) sequentially adding ferric chloride, nickel chloride, urea and anhydrous trisodium citrate into water, mixing uniformly, and then performing a hydrothermal reaction, and after the reaction, performing water washing, centrifugation and drying to obtain a nickel-iron layered double hydroxide (NiFe-LDH);
[0009] (2) dispersing a trivalent ruthenium salt and the nickel-iron layered double hydroxide in water, stirring at room temperature until completely dissolved, then adding sodium hydroxide into the above reaction materials, mixing thoroughly, and then placing in an oil bath to react, and after the reaction, performing centrifugation, washing and drying to obtain a ruthenium-modified nickel-iron layered double hydroxide catalytic material (Ru / NiFe-LDH).
[0010] The catalytic material of the present application is obtained by treating hydrated ruthenium chloride with a basic solution, and in the basic medium, the NiFe-LDH can provide abundant coordination sites for the ruthenium metal atoms (the surface of the LDH has abundant basic coordination sites, suitable for anchoring metal atoms to form high-activity catalytic centers), which is conducive to improving the dispersion of the ruthenium metal atoms on the NiFe-LDH, maximizing the utilization efficiency of the atoms, and anchoring the ruthenium on the surface of the NiFe-LDH through oxygen coordination bonds.
[0011] In step (1), the temperature of the hydrothermal reaction is 130-150 DEG C, and the reaction time is 22-24 h.
[0012] In step (1), the mass ratio of the ferric chloride, the nickel chloride, the urea and the anhydrous trisodium citrate is 47:344:336:12. The urea is continuously decomposed into hydroxyl ions and bicarbonate ions in the hydrothermal process, and the metal salt generates the LDH; different amounts of the trisodium citrate affect the flaky structure of the NiFe-LDH and the interlayer spacing of the NiFe-LDH, and the large interlayer spacing and the ultrathin flaky structure are conducive to the anchoring of the Ru on the NiFe-LDH and the better dispersion of the Ru on the NiFe-LDH.
[0013] In step (1), the drying is vacuum drying, the temperature of the vacuum drying is 50-60 DEG C, and the drying time is 12-14 h.
[0014] In step (2), the trivalent ruthenium salt is one of ruthenium trichloride (RuCl3), ruthenium trichloride trihydrate (RuCl3·3H2O) or hydrated ruthenium trichloride (RuCl3·xH2O).
[0015] In step (2), the mixed mass ratio of the trivalent ruthenium salt, the sodium hydroxide and the nickel-iron layered double hydroxide is 1.1-2.9:10:25. In the alkaline environment provided by the sodium hydroxide, abundant coordination sites are provided for the anchoring of the ruthenium, the dispersion of the ruthenium is improved, the utilization efficiency of the atoms is maximized, and the degradation effect is improved.
[0016] In step (2), the oil bath temperature is 50-55 DEG C, and the oil bath time is 7-8h.
[0017] In step (2), the drying is vacuum drying, the temperature of the vacuum drying is 50-60 DEG C, and the drying time is 9-15h.
[0018] The application of the ruthenium-modified nickel-iron layered double hydroxide catalytic material in degrading organic matter in wastewater is as follows: the addition amount of the catalytic material is 0.05g, the initial pH value of the reaction solution is 3-9 at 15-35 DEG C, the addition amount of PMS is 0.25-0.75g, and the initial concentration of atrazine is 10mg / L -1 The catalyst can effectively excite PMS to make the O-O bond dissociate to produce strong oxidizing species, so that the organic pollutant atrazine in water is degraded, and the atrazine is finally converted into water and carbon dioxide.
[0019] Advantages: Compared with the prior art, the ruthenium-modified nickel-iron layered double hydroxide catalytic material has the following significant advantages: the ruthenium-modified nickel-iron layered double hydroxide catalytic material has a nanosheet stacking structure, which can effectively improve the dispersity of the metal active site ruthenium on the nickel-iron layered double hydroxide, so that a catalytic material with more accessible active metal sites is obtained, and the catalytic activity of the catalytic material in activating PMS to degrade atrazine is greatly improved, and efficient catalytic degradation of atrazine is realized. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 The SEM image of the catalytic material prepared in Example 1 is shown in the figure;
[0021] Figure 2 The SEM image of the catalytic material prepared in Example 5 is shown in the figure;
[0022] Figure 3 The XRD image of the catalytic material prepared in Example 1 and Example 5 is shown in the figure. DETAILED DESCRIPTION
[0023] Example 1
[0024] A preparation method of a pure nickel-iron layered double hydroxide catalytic material, specifically comprising the following steps:
[0025] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride were added to 75 mL of deionized water, mixed uniformly under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate were added to the beaker, and the mixture was stirred for 30 min until it was completely dissolved into a light green transparent solution, then the mixed solution was transferred to a 100 mL polytetrafluoroethylene lined autoclave, and a hydrothermal reaction was carried out in a 150℃ oven for 24 hours to obtain a mixture solution with a yellowish brown color, the product was washed with water, centrifuged, and dried in a vacuum oven at 50℃ for 12 h, and after drying, NiFe-LDH was obtained;
[0026] (2) 0.25 g of NiFe-LDH was dispersed in 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution was poured into a 150 mL round-bottom flask, and 0.1 g of sodium hydroxide was added to the above solution, and stirred at 50℃ for 8 h to obtain a dark green sample, which was washed with deionized water and ethanol, and after washing, the sample was dried in a vacuum oven at 50℃ for 12 h to obtain a catalytic material.
[0027] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and high-purity liquid chromatography was used to measure the degradation of atrazine activated by the catalytic material PMS to evaluate the degradation of atrazine: the reaction conditions of the degradation were room temperature, the initial concentration of atrazine was 10 mg·L -1 , 0.05 g of the catalytic material prepared in Example 1 was first added, and after stirring for 30 min, 0.5 g of PMS was added, and the test results showed that the degradation activity of the catalytic material on atrazine was 56.2% within 180 min.
[0028] Example 2
[0029] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material of the application specifically comprises the following steps:
[0030] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride were added to 75 mL of deionized water, mixed uniformly under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate were added to the beaker, and the mixture was stirred for 30 min until it was completely dissolved into a light green transparent solution, then the mixed solution was transferred to a 100 mL polytetrafluoroethylene lined autoclave, and a hydrothermal reaction was carried out in a 150℃ oven for 24 hours to obtain a mixture solution with a yellowish brown color, the product was washed with water, centrifuged, and dried in a vacuum oven at 50℃ for 12 h, and after drying, NiFe-LDH was obtained;
[0031] (2) 0.0107 g of RuCl3·nH2O and 0.25 g of NiFe-LDH were dispersed into 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution was poured into a 150 mL round-bottom flask, 0.1 g of sodium hydroxide was added to the above solution, and stirring was performed in an oil bath at 50℃ for 8 h to obtain a dark green sample, which was sequentially washed with deionized water and ethanol, and after washing, the sample was dried in a vacuum oven at 50℃ for 12 h to obtain a catalytic material (Ru / NiFe-LDH).
[0032] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and high-purity liquid chromatography was used to measure the degradation of atrazine by the catalytic material activated PMS: the reaction conditions of the degradation were room temperature, the initial concentration of atrazine was 10 mg·L -1 , 0.05 g of the catalytic material prepared in Example 2 was first added, and after stirring for 30 min, 0.5 g of PMS was added, and the test results showed that the degradation activity of the catalytic material on atrazine was 97.5% within 180 min.
[0033] Example 3
[0034] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material of the application specifically comprises the following steps:
[0035] (1) 0.0235 g of iron chloride and 0.172 g of nickel chloride were added to 75 mL of deionized water, and were uniformly mixed under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate were then added to the beaker, and were stirred magnetically for 30 min until completely dissolved into a light green transparent solution, and then the mixed solution was transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and was subjected to a hydrothermal reaction in a 150℃ oven for 24 h to obtain a tan-colored mixed solution, the product was washed with water, centrifuged, and dried in a 50℃ vacuum oven for 12 h, and after drying, a NiFe-LDH was obtained;
[0036] (2) 0.0134 g of RuCl3·nH2O and 0.25 g of NiFe-LDH were dispersed into 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution was poured into a 150 mL round-bottom flask, 0.1 g of sodium hydroxide was added to the above solution, and stirring was performed in an oil bath at 50℃ for 8 h to obtain a dark green sample, which was sequentially washed with deionized water and ethanol, and after washing, the sample was dried in a vacuum oven at 50℃ for 12 h to obtain a catalytic material (Ru / NiFe-LDH).
[0037] The adsorption degradation process is carried out in a 500 mL beaker, atrazine is taken as a target pollutant, PMS is taken as an oxidant, and the degradation of atrazine is evaluated by measuring the catalytic material activated PMS by high-purity liquid chromatography: the reaction conditions of the degradation are as follows: at room temperature, the initial concentration of atrazine is 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 3 is added, and after stirring for 30 min, 0.5 g of PMS is added, and the test results show that the degradation activity of the catalytic material on atrazine is 100% within 180 min.
[0038] Example 4
[0039] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material of the application specifically comprises the following steps:
[0040] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride are added to 75 mL of deionized water, and uniformly mixed under magnetic stirring, then 0.168 g of urea and 0.006 g of anhydrous trisodium citrate are added to the beaker, and the mixture is stirred for 30 min until it is completely dissolved into a light green transparent solution, then the mixed solution is transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction is carried out in a 150°C oven for 24 hours to obtain a yellowish-brown mixed solution, the product is washed with water, centrifuged, and dried in a 50°C vacuum oven for 12 h, and after drying, the NiFe-LDH is obtained;
[0041] (2) 0.0199 g of RuCl3·nH2O and 0.25 g of NiFe-LDH are dispersed in 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution is poured into a 150 mL round-bottom flask, and 0.1 g of sodium hydroxide is added to the above solution, and the mixture is stirred at 50°C in an oil bath for 8 h to obtain a dark green sample, which is washed with deionized water and ethanol in sequence, and after washing, the sample is dried in a vacuum oven at 50°C for 12 h to obtain the catalytic material (Ru / NiFe-LDH).
[0042] The adsorption degradation process is carried out in a 500 mL beaker, atrazine is taken as a target pollutant, PMS is taken as an oxidant, and the degradation of atrazine is evaluated by measuring the catalytic material activated PMS by high-purity liquid chromatography: the reaction conditions of the degradation are as follows: at room temperature, the initial concentration of atrazine is 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 4 is added, and after stirring for 30 min, 0.5 g of PMS is added, and the test results show that the degradation activity of the catalytic material on atrazine is 100% within 180 min.
[0043] Example 5
[0044] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material according to the present application specifically comprises the following steps:
[0045] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride are added to 75 mL of deionized water, mixed uniformly under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate are added to the beaker, and the mixture is stirred magnetically for 30 min until it is completely dissolved into a light green transparent solution, then the mixed solution is transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction is carried out in a 150°C oven for 24 hours to obtain a yellowish-brown mixed solution, the product is washed with water, centrifuged, and dried in a 50°C vacuum oven for 12 h, and the dried NiFe-LDH is obtained;
[0046] (2) 0.0225 g of RuCl3·nH2O and 0.25 g of NiFe-LDH are dispersed into 50 mL of deionized water, the reaction solution is poured into a 150 mL round-bottom flask after stirring at room temperature for 1 h, 0.1 g of sodium hydroxide is added to the above solution, and the mixture is stirred in an oil bath at 50°C for 8 h to obtain a dark green sample, which is washed with deionized water and ethanol in sequence, and the sample is dried in a vacuum oven at 50°C for 12 h after washing to obtain the catalytic material (Ru / NiFe-LDH).
[0047] The adsorption degradation process is carried out in a 500 mL beaker, atrazine is used as the target pollutant, PMS is used as the oxidant, and the degradation of atrazine is evaluated by measuring the catalytic material activated PMS using high-purity liquid chromatography: the reaction conditions of the degradation are as follows: the initial concentration of atrazine is 10 mg·L -1 , 0.05 g of the catalytic material prepared in Example 5 is first added, and after stirring for 30 min, 0.5 g of PMS is added, and the test results show that the degradation activity of the catalytic material on atrazine is 100% within 60 min.
[0048] Example 6
[0049] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material according to the present application specifically comprises the following steps:
[0050] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride are added to 75 mL of deionized water, mixed uniformly under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate are added to the beaker, and the mixture is stirred magnetically for 30 min until it is completely dissolved into a light green transparent solution, then the mixed solution is transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction is carried out in a 150°C oven for 24 hours to obtain a yellowish-brown mixed solution, the product is washed with water, centrifuged, and dried in a 50°C vacuum oven for 12 h, and the dried NiFe-LDH is obtained;
[0051] (2) 0.0286 g of RuCl3·nH2O and 0.25 g of NiFe-LDH were dispersed into 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution was poured into a 150 mL round-bottom flask, 0.1 g of sodium hydroxide was added to the above solution, and stirring was performed in an oil bath at 50 DEG C for 8 h to obtain a dark green sample, which was sequentially washed with deionized water and ethanol, and after washing, the sample was dried in a vacuum oven at 50 DEG C for 12 h to obtain a catalytic material (Ru / NiFe-LDH).
[0052] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the catalytic material activated PMS using high-purity liquid chromatography: the reaction conditions of the degradation were room temperature, the initial concentration of atrazine was 10 mg / L -1 , 0.05 g of the catalytic material prepared in Example 6 was first added, and after stirring for 30 min, 0.5 g of PMS was added, and the test results showed that the degradation activity of the catalytic material on atrazine was 99.4% within 90 min.
[0053] Example 7
[0054] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material of the application specifically comprises the following steps:
[0055] (1) 0.0235 g of iron chloride and 0.172 g of nickel chloride were added to 75 mL of deionized water, and were uniformly mixed under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate were then added to the beaker, and were stirred magnetically for 30 min until completely dissolved into a light green transparent solution, the mixed solution was then transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction was performed in a 150 DEG C oven for 24 h to obtain a tan mixed solution, the product was washed with water, centrifuged, and dried in a 50 DEG C vacuum oven for 12 h to obtain NiFe-LDH;
[0056] (2) 0.0225 g of RuCl3 and 0.25 g of NiFe-LDH were dispersed into 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution was poured into a 150 mL round-bottom flask, 0.1 g of sodium hydroxide was added to the above solution, and stirring was performed in an oil bath at 50 DEG C for 8 h to obtain a dark green sample, which was sequentially washed with deionized water and ethanol, and after washing, the sample was dried in a vacuum oven at 50 DEG C for 12 h to obtain a catalytic material (Ru / NiFe-LDH).
[0057] The adsorption degradation process is carried out in a 500 mL beaker, atrazine is taken as a target pollutant, PMS is taken as an oxidant, and the degradation of atrazine is evaluated by measuring the catalytic material activated PMS by high-purity liquid chromatography: the reaction conditions of the degradation are as follows: at room temperature, the initial concentration of atrazine is 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 7 is added, and after stirring for 30 min, 0.5 g of PMS is added, and the test results show that the degradation activity of the catalytic material on atrazine within 60 min is 99.3%.
[0058] Example 8
[0059] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material of the application specifically comprises the following steps:
[0060] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride are added to 75 mL of deionized water, and uniformly mixed under magnetic stirring, then 0.168 g of urea and 0.006 g of anhydrous trisodium citrate are added to the beaker, and the mixture is stirred for 30 min until it is completely dissolved into a light green transparent solution, then the mixed solution is transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction is carried out in a 150℃ oven for 24 hours to obtain a khaki-colored mixed solution, the product is washed with water, centrifuged, and dried in a 50℃ vacuum oven for 12 h, and after drying, the NiFe-LDH is obtained.
[0061] (2) 0.0225 g of RuCl3·3H2O and 0.25 g of NiFe-LDH are dispersed in 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution is poured into a 150 mL round-bottom flask, and 0.1 g of sodium hydroxide is added to the above-mentioned solution, and stirring is carried out in an oil bath at 50℃ for 8 h to obtain a dark green sample, which is sequentially washed with deionized water and ethanol, and after washing, the sample is dried in a vacuum oven at 50℃ for 12 h to obtain the catalytic material (Ru / NiFe-LDH).
[0062] The adsorption degradation process is carried out in a 500 mL beaker, atrazine is taken as a target pollutant, PMS is taken as an oxidant, and the degradation of atrazine is evaluated by measuring the catalytic material activated PMS by high-purity liquid chromatography: the reaction conditions of the degradation are as follows: at room temperature, the initial concentration of atrazine is 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 8 is added, and after stirring for 30 min, 0.5 g of PMS is added, and the test results show that the degradation activity of the catalytic material on atrazine within 60 min is 99.2%.
[0063] Example 9
[0064] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material according to the present application specifically comprises the following steps:
[0065] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride are added to 75 mL of deionized water, mixed uniformly under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate are added to the beaker, and the mixture is stirred magnetically for 30 min until it is completely dissolved into a light green transparent solution, then the mixed solution is transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction is carried out in a 150°C oven for 24 hours to obtain a yellowish-brown mixed solution, the product is washed with water, centrifuged, and dried in a 50°C vacuum oven for 12 h, and the dried NiFe-LDH is obtained;
[0066] (2) 0.0225 g of RuCl3·3H2O and 0.25 g of NiFe-LDH are dispersed in 50 mL of deionized water, the reaction solution is poured into a 150 mL round-bottom flask after stirring at room temperature for 1 h, 0.1 g of sodium hydroxide is added to the above solution, and the mixture is stirred in an oil bath at 50°C for 8 h to obtain a dark green sample, which is washed with deionized water and ethanol in sequence, and the sample is dried in a vacuum oven at 40°C for 12 h after washing to obtain the catalytic material (Ru / NiFe-LDH).
[0067] The adsorption degradation process is carried out in a 500 mL beaker, atrazine is used as the target pollutant, PMS is used as the oxidant, and the degradation of atrazine is evaluated by measuring the catalytic material activated PMS using high-purity liquid chromatography: the reaction conditions of the degradation are as follows: the initial concentration of atrazine is 10 mg·L -1 , 0.05 g of the catalytic material prepared in Example 9 is first added, and after stirring for 30 min, 0.5 g of PMS is added, and the test results show that the degradation activity of the catalytic material on atrazine is 100% within 60 min.
[0068] Example 10
[0069] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material according to the present application specifically comprises the following steps:
[0070] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride are added to 75 mL of deionized water, mixed uniformly under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate are added to the beaker, and the mixture is stirred magnetically for 30 min until it is completely dissolved into a light green transparent solution, then the mixed solution is transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction is carried out in a 150°C oven for 24 hours to obtain a yellowish-brown mixed solution, the product is washed with water, centrifuged, and dried in a 50°C vacuum oven for 12 h, and the dried NiFe-LDH is obtained;
[0071] (2) 0.0225 g of RuCl3·3H2O and 0.25 g of NiFe-LDH were dispersed into 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution was poured into a 150 mL round-bottom flask, 0.1 g of sodium hydroxide was added to the above solution, and stirring was performed in an oil bath at 50°C for 8 h to obtain a dark green sample, which was sequentially washed with deionized water and ethanol, and after washing, the sample was dried in a vacuum oven at 60°C for 12 h to obtain a catalytic material (Ru / NiFe-LDH).
[0072] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the catalytic material activated PMS using high-purity liquid chromatography: the reaction conditions of the degradation were room temperature, the initial concentration of atrazine was 10 mg·L -1 , 0.05 g of the catalytic material prepared in Example 10 was first added, and after stirring for 30 min, 0.5 g of PMS was added, and the test results showed that the degradation activity of the catalytic material on atrazine was 100% within 60 min.
[0073] Example 11
[0074] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material of the present application specifically comprises the following steps:
[0075] (1) 0.0235 g of iron chloride and 0.172 g of nickel chloride were added to 75 mL of deionized water, and were mixed uniformly under magnetic stirring, 0.168 g of urea and 0.006 g of anhydrous trisodium citrate were then added to the beaker, and magnetic stirring was performed for 30 min until complete dissolution into a light green transparent solution, the mixed solution was then transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction was performed in a 150°C oven for 24 h to obtain a tan-colored mixed solution, the product was washed with water, centrifuged, and dried in a 50°C vacuum oven for 12 h, and after drying, a NiFe-LDH was obtained;
[0076] (2) 0.0225 g of RuCl3·3H2O and 0.25 g of NiFe-LDH were dispersed into 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution was poured into a 150 mL round-bottom flask, 0.1 g of sodium hydroxide was added to the above solution, and stirring was performed in an oil bath at 50°C for 8 h to obtain a dark green sample, which was sequentially washed with deionized water and ethanol, and after washing, the sample was dried in a vacuum oven at 50°C for 9 h to obtain a catalytic material (Ru / NiFe-LDH).
[0077] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activity of the catalytic material activated PMS by high purity liquid chromatography: the reaction conditions of the degradation were room temperature, the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 11 was added, and after stirring for 30 min, 0.5 g of PMS was added, and the test results showed that the degradation activity of the catalytic material to atrazine within 60 min was 100%.
[0078] Example 12
[0079] The preparation method of the ruthenium-modified nickel-iron layered double hydroxide catalytic material of the application specifically comprises the following steps:
[0080] (1) 0.0235 g of ferric chloride and 0.172 g of nickel chloride were added to 75 mL of deionized water, and stirred uniformly under magnetic stirring, then 0.168 g of urea and 0.006 g of anhydrous trisodium citrate were added to the beaker, and the mixture was stirred for 30 min until it was completely dissolved into a light green transparent solution, then the mixed solution was transferred to a 100 mL polytetrafluoroethylene-lined autoclave, and a hydrothermal reaction was carried out in a 150℃ oven for 24 hours, obtaining a khaki-colored mixed solution, the product was washed with water, centrifuged, and dried in a 50℃ vacuum oven for 12 h, and after drying, the NiFe-LDH was obtained.
[0081] (2) 0.0225 g of RuCl3·3H2O and 0.25 g of NiFe-LDH were dispersed in 50 mL of deionized water, and after stirring at room temperature for 1 h, the reaction solution was poured into a 150 mL round-bottom flask, and 0.1 g of sodium hydroxide was added to the above solution, and stirred at 50℃ in an oil bath for 8 h, obtaining a dark green sample, which was washed with deionized water and ethanol in sequence, and after washing, the sample was dried in a vacuum oven at 50℃ for 15 h, obtaining the catalytic material (Ru / NiFe-LDH).
[0082] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activity of the catalytic material activated PMS by high purity liquid chromatography: the reaction conditions of the degradation were room temperature, the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 11 was added, and after stirring for 30 min, 0.5 g of PMS was added, and the test results showed that the degradation activity of the catalytic material to atrazine within 60 min was 100%.
[0083] Example 13
[0084] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.5 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 99.6% within 90 min.
[0085] Example 14
[0086] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.5 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 99.6% within 90 min.
[0087] Example 15
[0088] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.5 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 99.6% within 90 min.
[0089] Example 16
[0090] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.0125 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.5 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 76.6% within 180 min.
[0091] Example 17
[0092] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.025 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.5 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 91.4% within 180 min.
[0093] Example 18
[0094] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.075 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.5 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 100% within 60 min.
[0095] Example 19
[0096] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.125 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 100% within 180 min.
[0097] Example 20
[0098] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.25 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 100% within 150 min.
[0099] Example 21
[0100] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 5 was added to the solution, and after stirring for 30 min, 0.75 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 99.2% within 60 min.
[0101] Example 22
[0102] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.2 M H2SO4 was added to the solution to make the pH value of the solution 3, and then 0.05 g of the catalytic material prepared in Example 5 was added to the solution. After stirring for 30 min, 0.5 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 95.0% within 180 min.
[0103] Example 23
[0104] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.2 M KOH was added to the solution to make the pH value of the solution 6, and then 0.05 g of the catalytic material prepared in Example 5 was added to the solution. After stirring for 30 min, 0.5 g of PMS was added. The test results showed that the degradation activity of the catalytic material for atrazine was 99.5% within 60 min.
[0105] Example 24
[0106] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography. The reaction conditions for this degradation were as follows: the initial concentration of atrazine was 10 mg·L -1, first add 0.2M KOH to the solution to make the pH value of the solution 7, then add 0.05g of the catalytic material prepared in Example 5 to the solution, stir for 30min, and then add 0.5g of PMS. The test results show that the degradation activity of the catalytic material for atrazine within 60min is 90.2%.
[0107] Example 25
[0108] The adsorption degradation process was carried out in a 500mL beaker, with atrazine as the target pollutant and PMS as the oxidant. The degradation of atrazine was evaluated by measuring the catalytic material activated PMS using high-purity liquid chromatography. The reaction conditions for the degradation were as follows: the initial concentration of atrazine was 10mg·L -1 , first add 0.2M KOH to the solution to make the pH value of the solution 9, then add 0.05g of the catalytic material prepared in Example 5 to the solution, stir for 30min, and then add 0.5g of PMS. The test results show that the degradation activity of the catalytic material for atrazine within 60min is 96.67%.
[0109] Example 26
[0110] The adsorption degradation process was carried out in a 500mL beaker, with atrazine as the target pollutant and PMS as the oxidant. The degradation of atrazine was evaluated by measuring the catalytic material activated PMS using high-purity liquid chromatography. The reaction conditions for the degradation were as follows: the initial concentration of atrazine was 10mg·L -1 , first add 0.2M KOH to the solution to make the pH value of the solution 9, then add 0.05g of the catalytic material prepared in Example 5 to the solution, stir for 30min, and then add 0.5g of PMS. The test results show that the degradation activity of the catalytic material for atrazine within 60min is 96.67%.
[0111] Example 27
[0112] The adsorption degradation process was carried out in a 500mL beaker, with atrazine as the target pollutant and PMS as the oxidant. The degradation of atrazine was evaluated by measuring the catalytic material activated PMS using high-purity liquid chromatography. The reaction conditions for the degradation were as follows: the initial concentration of atrazine was 10mg·L -1 , first add 0.2M KOH to the solution to make the pH value of the solution 9, then add 0.05g of the catalytic material prepared in Example 5 to the solution, stir for 30min, and then add 0.5g of PMS. The test results show that the degradation activity of the catalytic material for atrazine within 60min is 96.67%.
[0113] Example 28
[0114] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activated PMS of the catalytic material using high-purity liquid chromatography. The reaction conditions of the degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.5 g of PMS and 0.2 M of KOH were added to adjust the pH of the solution, and the pH of the solution was kept at 7. The test results showed that the degradation activity of the catalytic material for atrazine within 60 min was 98.6%.
[0115] Example 29
[0116] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activated PMS of the catalytic material using high-purity liquid chromatography. The reaction conditions of the degradation were as follows: the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Example 5 was added, and after stirring for 30 min, 0.5 g of PMS and 0.2 M of KOH were added to adjust the pH of the solution, and the pH of the solution was kept at 7. The test results showed that the degradation activity of the catalytic material for atrazine within 60 min was 98.6%.
[0117] It can be known from the comparison of Examples 1 to 6 that the amount of introduced hydrated ruthenium trichloride has a great influence on the degradation of atrazine by the activated PMS of the catalytic material. The experimental results show that when 0.0225 g of hydrated ruthenium trichloride is added, the degradation of atrazine by the activated PMS is the best. It can be known from the comparison of Examples 13, 14 and 15 that the reaction temperature has a great influence on the catalytic activity during the degradation reaction. The higher the temperature, the better the effect of the degradation of atrazine by the activated PMS of the catalytic material. It can be known from the comparison of Examples 5, 16, 17 and 18 that different initial catalyst concentrations have a significant influence on the degradation of atrazine. The degradation of atrazine is shortened from 180 min to 60 min. It can be known from the comparison of Examples 5, 19, 20 and 21 that the amount of PMS added during the catalytic reaction has a great influence on the degradation effect. The more PMS added, the better the removal effect of atrazine. However, the degradation rate does not change when 0.75 g of PMS is added, which indicates that 0.5 g of PMS can generate enough free radicals. It can be known from the comparison of Examples 5, 26, 27, 28 and 29 that the constant pH value of the reaction solution has a great influence on the catalytic activity. The catalytic performance is good under strong acid, neutral and weak alkaline conditions, and the catalytic performance is significantly improved under strong alkaline conditions.
[0118] Comparative Example 1
[0119] The preparation method of Comparative Example 1 is basically the same as that of Example 5, the only difference is that the mass ratio of iron chloride, nickel chloride, urea and anhydrous trisodium citrate is adjusted to 47:204:100:12, and the obtained iron-nickel carrier structure is not a layered double hydroxide.
[0120] The adsorption degradation process is carried out in a 500 mL beaker, atrazine is taken as the target pollutant, PMS is taken as the oxidant, and the degradation of atrazine is evaluated by measuring the catalytic material activated PMS by high-purity liquid chromatography: the reaction conditions of the degradation are room temperature, the initial concentration of atrazine is 10 mg·L -1 , first 0.05 g of the catalytic material prepared in Comparative Example 1 is added, after stirring for 30 min, 0.5 g of PMS is added, and the test results show that the degradation activity of the catalytic material to atrazine within 180 min is 12.3%.
[0121] Comparative Example 2
[0122] The preparation method of Comparative Example 2 is basically the same as that of Example 5, the only difference is that the temperature and time of the hydrothermal reaction are adjusted to 240℃ and 18 h respectively, and the obtained iron-nickel carrier structure is not a layered double hydroxide.
[0123] The adsorption degradation process is carried out in a 500 mL beaker, atrazine is taken as the target pollutant, PMS is taken as the oxidant, and the degradation of atrazine is evaluated by measuring the catalytic material activated PMS by high-purity liquid chromatography: the reaction conditions of the degradation are room temperature, the initial concentration of atrazine is 10 mg·L -1 , first 0.05 g of the catalytic material prepared in Comparative Example 2 is added, after stirring for 30 min, 0.5 g of PMS is added, and the test results show that the degradation activity of the catalytic material to atrazine within 180 min is 18.5%.
[0124] Comparative Example 3
[0125] The preparation method of Comparative Example 3 is basically the same as that of Example 5, the only difference is that MgAl-LDH is prepared in step (1), and MgAl-LDH is taken as the carrier, and finally a ruthenium-modified magnesium-aluminum layered double hydroxide catalytic material is obtained.
[0126] MgCl2 6H2O (1.30 g) and Al(NO3)3 9H2O (1.20 g) are dissolved in 250 mL of water, and then 3.45 g of urea is added; after boiling for 24 h (refluxing at 110℃ for 24 h), a sample is obtained, the sample is washed with a large amount of deionized water, and after washing, the solid is dried at 110℃ overnight, and then ground into a powder, which is MgAl-LDH.
[0127] The adsorption degradation process was carried out in a 500 mL beaker, atrazine was used as the target pollutant, PMS was used as the oxidant, and the degradation of atrazine was evaluated by measuring the activation of PMS by the catalytic material using high-purity liquid chromatography: the reaction conditions of the degradation were room temperature, the initial concentration of atrazine was 10 mg·L -1 First, 0.05 g of the catalytic material prepared in Comparative Example 3 was added, and after stirring for 30 min, 0.5 g of PMS was added, and the test results showed that the degradation activity of the catalytic material for atrazine was 10.7% within 180 min.
[0128] Figure 1 The SEM image of the nickel-iron layered double hydroxide shows that it is assembled by a large number of nanosheets; Figure 2 The product obtained by adding Ru to the precursor NiFe-LDH has little difference in morphology from NiFe-LDH, and the surface is also composed of stacked nanosheets, indicating that the introduction of Ru does not change the micro-morphology of the catalyst; Figure 3 The X-ray diffraction of NiFe-LDH and Ru-loaded NiFe-LDH shows that the positions of their characteristic peaks are almost identical, and no diffraction peak related to Ru species is detected, which indicates that the Ru metal on Ru / NiFe-LDH has good dispersion and no obvious aggregation.
Claims
1. The application of a ruthenium-modified nickel-iron layered double hydroxide catalytic material in the degradation of organic matter in wastewater, characterized in that, The specific application process is as follows: at 25℃, the initial concentration of atrazine is 10 mg·L⁻¹. −1 First, 0.05g of catalyst material was added and stirred for 30 minutes. Then, 0.5g of PMS and 0.2M KOH were added to adjust the pH of the solution, keeping the pH at 9. The degradation activity of atrazine by the catalyst material was 100% within 5 minutes. The preparation method of the above-mentioned catalytic material includes the following steps: (1) Add 0.0235g of ferric chloride and 0.172g of nickel chloride to 75mL of deionized water and mix thoroughly with magnetic stirring. Then add 0.168g of urea and 0.006g of anhydrous trisodium citrate to a beaker and stir magnetically for 30min until completely dissolved into a light green transparent solution. Then transfer the mixed solution to a polytetrafluoroethylene-lined counter-pressure reactor and heat at 150°C. o A hydrothermal reaction was carried out in a C oven for 24 hours to obtain a yellowish-brown mixed solution. The product was washed with water, centrifuged, and then dried at 50°C. o NiFe-LDH was obtained by drying in a vacuum oven for 12 hours. (2) Disperse 0.0225g RuCl3·nH2O and 0.25g NiFe-LDH into 50mL deionized water, stir at room temperature for 1h, pour the reaction solution into a 150mL round-bottom flask, add 0.1g sodium hydroxide to the above solution, stir in an oil bath at 50°C for 8h to obtain a dark green sample, wash with deionized water and ethanol in sequence, and dry the sample in a vacuum oven at 50°C for 12h to obtain the catalyst material.