Preparation method and application of Fe3O4 / active coke ZIF-67 core-shell material
By loading Fe3O4 nanoparticles and a ZIF-67 shell onto the surface of activated carbon, Fe3O4/activated carbon@ZIF-67 core-shell materials were prepared, which solved the problem of insufficient adsorption performance of activated carbon materials and achieved efficient removal of tetracycline and convenient material recycling.
Patent Information
- Application Number
- CN202511161398.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-19
- Publication Date
- 2025-11-11
AI Technical Summary
Existing activated carbon materials have limited adsorption performance in removing tetracycline-type small molecule organic pollutants from water, mainly due to their simple surface functional structure and insufficient active sites.
Fe3O4/activated coke@ZIF-67 core-shell material was prepared by loading Fe3O4 nanoparticles and ZIF-67 shell on the surface of activated coke, which improved the adsorption performance of the material and endowed it with magnetism, making it easy to recycle.
It significantly improved the adsorption capacity for tetracycline to 193 mg/g, which is 133 mg/g higher than that of unmodified activated carbon, and enabled convenient recovery through magnetism, thus reducing costs.
Abstract
Description
Technical Field
[0001] This invention relates to the field of wastewater treatment technology, specifically to a method for preparing and applying Fe3O4 / activated coke@ZIF-67 core-shell material. Background Technology
[0002] With the widespread use of antibiotics in medicine, aquaculture, and agriculture, antibiotic pollution in water bodies has become increasingly serious, posing a significant global environmental challenge. Tetracycline antibiotics, due to their high usage, incomplete metabolism, and strong stability, are frequently detected in surface water, groundwater, and even drinking water, seriously threatening ecosystems and human health. Therefore, developing efficient, economical, and environmentally friendly tetracycline removal technologies has become an important research direction in the field of water treatment.
[0003] Currently, adsorption is widely used in the removal of antibiotics from wastewater due to its advantages such as simple operation, relatively low cost, and no secondary pollution. Activated carbon, as an adsorbent material with low cost, large specific surface area, and well-developed microporous structure, has received widespread attention in water treatment in recent years. However, the adsorption performance of traditional activated carbon for small molecule organic pollutants such as tetracyclines still needs improvement, mainly due to its limited surface functional structure and limited active sites.
[0004] ZIF-67 (metal-organic framework) has been widely studied for the adsorption and removal of pollutants in water due to its excellent pore structure, large specific surface area, and good stability. Meanwhile, Fe3O4 nanoparticles possess good magnetic properties, facilitating the separation and recovery of the material. By synergistically loading Fe3O4 and ZIF-67 onto the surface of activated carbon, not only can the adsorption performance of the activated carbon be effectively improved, but the material can also be endowed with good magnetic separation properties, achieving efficient removal of antibiotics and convenient recovery of the material in water treatment processes.
[0005] Therefore, developing a method for preparing Fe3O4 / activated coke@ZIF-67 core-shell material and applying it to the removal of antibiotics such as tetracycline from wastewater has significant theoretical and practical value. Summary of the Invention
[0006] The purpose of this invention is to provide a method for preparing Fe3O4 / activated coke@ZIF-67 core-shell material and its application, in order to solve the problem that existing activated coke materials are limited by their single surface functional structure and limited active sites, resulting in low adsorption and removal efficiency of small molecule organic pollutants such as tetracyclines in wastewater.
[0007] To achieve the above objectives, the present invention adopts the following technical solution: a method for preparing Fe3O4 / activated coke@ZIF-67 core-shell material, comprising the following steps:
[0008] S1, Pretreatment of activated carbon
[0009] The activated coke is pulverized and sieved to obtain activated coke powder; the activated coke powder is thoroughly mixed with an acid solution, filtered, washed and dried to obtain acid-modified activated coke material;
[0010] Preparation of S2, Fe3O4 hollow microspheres@activated charcoal carrier
[0011] Ferric chloride and trisodium citrate were dissolved in ethylene glycol, stirred and clarified, and then sodium acetate was added. Subsequently, S1 acid-modified activated carbon material was added, ultrasonically dispersed, and reacted in an autoclave. After the reaction was completed, the mixture was cooled, filtered, and magnetically separated. The magnetically separated material was washed with water, alcohol, and vacuum dried to obtain Fe3O4 hollow microspheres@activated carbon carrier.
[0012] S3, ZIF-67 shell growth
[0013] Cobalt nitrate hexahydrate was dissolved in methanol to obtain a methanol solution of cobalt ions. The Fe3O4 hollow microspheres obtained in S2 were ultrasonically dispersed in the methanol solution, and then a solution containing Hmim was added. After the reaction was completed, the complex was recovered by magnetization. The mixture was washed with water and ethanol alternately until neutral and dried to obtain the Fe3O4 / activated coke@ZIF-67 core-shell material of the present invention.
[0014] Further, in S1, the activated coke is pulverized and passed through a 100-200 mesh sieve; the acid solution includes a nitric acid solution with a concentration of 2-5 mol / L; the mass-to-volume ratio of activated coke powder to acid solution is 1:10-20; during thorough mixing, the temperature is 60-80℃, the stirring intensity is 100-200 rpm, and the time is 2-4 h; the mixture is repeatedly washed with deionized water until neutral, and then dried at 105℃ for 8-12 h.
[0015] Furthermore, in S2, ferric chloride is ferric chloride hexahydrate, trisodium citrate is trisodium citrate dihydrate, and sodium acetate is sodium acetate trihydrate; the mass ratio of ethylene glycol, ferric chloride, trisodium citrate, sodium acetate, and acid-modified activated coke material is 800-1000:20-30:1:50-100:5-15.
[0016] Furthermore, the ultrasonic dispersion frequency is 20–40 kHz, the power is 200–600 W, and the dispersion time is 10–30 min; the autoclave reaction temperature is 180–220 °C, and the reaction time is 10–20 h.
[0017] Furthermore, the water washing uses deionized water and is performed 3 to 5 times; the alcohol washing uses anhydrous ethanol and is performed 1 to 3 times; the vacuum drying temperature is 50 to 80°C and the drying time is 6 to 10 hours.
[0018] Furthermore, in S3, the mass-to-volume ratio of Fe3O4 hollow microspheres@activated char carrier to methanol is 1:40-60, and the mass ratio of Fe3O4 hollow microspheres@activated char carrier to cobalt nitrate hexahydrate is 1:1-2.
[0019] Furthermore, the mass ratio of cobalt ions to Hmim is 1:30-50. After adding the solution containing cobalt ions and Hmim, the mixture is reacted at room temperature in a shaking oven for 20-30 hours, with a shaking frequency of 60-120 rpm and an amplitude of 26 mm.
[0020] Furthermore, in step S3, the drying temperature is 60–80°C, and the drying time is 12–24 hours.
[0021] Application of Fe3O4 / activated coke@ZIF-67 core-shell material for antibiotic adsorption and removal in wastewater treatment.
[0022] Furthermore, the Fe3O4 / activated char@ZIF-67 core-shell material described above can adsorb tetracycline up to 193 mg / g, which is 133 mg / g higher than that of unmodified activated char.
[0023] The beneficial effects of this invention are:
[0024] 1. The Fe3O4 / activated coke@ZIF-67 core-shell material obtained by this invention can effectively adsorb and remove antibiotics in wastewater, and the adsorption and removal capacity of tetracycline can reach 193 mg / g, which has broad application prospects.
[0025] 2. The Fe3O4 / activated coke@ZIF-67 core-shell material obtained by this invention is magnetic, enabling efficient removal of antibiotics and convenient material recycling during water treatment, which helps reduce costs and is of great significance for resource recycling. Detailed Implementation
[0026] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention.
[0027] Example 1
[0028] S1, Pretreatment of activated carbon
[0029] Take activated coke raw material, crush it and pass it through a 200-mesh sieve to obtain activated coke powder, and set it aside. Take 2 mol / L nitric acid solution, add the activated coke powder to the nitric acid solution, wherein the mass-volume ratio (kg / L) of activated coke powder to nitric acid solution is 1:15. Stir at 120 rpm for 2 hours at 80℃ to mix thoroughly, then filter, wash with deionized water until neutral, and dry at 105℃ for 12 hours to obtain acid-modified activated coke material, and set it aside.
[0030] Preparation of S2, Fe3O4 hollow microspheres@activated charcoal carrier
[0031] Dissolve 1.35g FeCl3·6H2O and 0.05g trisodium citrate dihydrate in 40mL ethylene glycol. After stirring and clarifying, add 3.6g sodium acetate trihydrate, followed by 0.5g S1 acid-modified activated carbon material. Ultrasonically disperse for 30min at a frequency of 28kHz and a power of 400W to obtain a dispersion.
[0032] The dispersion was transferred to a 50 mL autoclave and reacted at 200 °C for 15 h. After cooling, the precipitate was separated by magnetic separation, washed 4 times with deionized water and 1 time with ethanol, and then vacuum dried at 60 °C for 6 h to obtain the magnetic carrier, namely Fe3O4 hollow microspheres@activated charcoal carrier.
[0033] S3, ZIF-67 shell growth
[0034] ZIF-67 shell growth based on S2 magnetic carrier:
[0035] Take 50 mL of methanol and dissolve 1.16 g of Co(NO3)2·6H2O in methanol to obtain a methanol solution of cobalt ions. Take 1 g of the above magnetic carrier and ultrasonically disperse it in the methanol solution under the same ultrasonic conditions as above. Then soak it for 1 h, and then slowly add a solution containing 9.5 g of Hmim (2-methylimidazole). Place the mixture in a shaking box and react at room temperature for 24 h with a shaking frequency of 80 rpm and an amplitude of 26 mm.
[0036] After the reaction was completed, the complex was filtered and recovered by magnet. It was washed with water / ethanol alternately until neutral and dried at 80°C for 20 h to finally obtain Fe3O4 / activated coke@ZIF-67 core-shell material.
[0037] Experiments were conducted on the modified material, and the results showed that the material could adsorb tetracycline up to 193 mg / g, which was 133 mg / g higher than that of the unmodified activated carbon. In addition, the material has good magnetic properties and can be effectively recycled.
[0038] This invention is not limited to the preferred embodiments described above. Anyone can derive other forms of products under the guidance of this invention. However, regardless of any changes made in their shape or structure, any technical solution that is the same as or similar to this application falls within the protection scope of this invention.
Claims
1. A method for preparing a Fe3O4 / activated coke@ZIF-67 core-shell material, characterized in that, Includes the following steps: S1, Pretreatment of activated carbon The activated coke is pulverized and sieved to obtain activated coke powder; The activated coke powder is thoroughly mixed with an acid solution, filtered, washed, and dried to obtain the acid-modified activated coke material. Preparation of S2, Fe3O4 hollow microspheres@activated charcoal carrier Ferric chloride and trisodium citrate were dissolved in ethylene glycol, stirred and clarified, and then sodium acetate was added. Subsequently, S1 acid-modified activated carbon material was added, ultrasonically dispersed, and reacted in an autoclave. After the reaction was completed, the mixture was cooled, filtered, and magnetically separated. The magnetically separated material was washed with water, alcohol, and vacuum dried to obtain Fe3O4 hollow microspheres@activated carbon carrier. S3, ZIF-67 shell growth Cobalt nitrate hexahydrate was dissolved in methanol to obtain a methanol solution of cobalt ions. The Fe3O4 hollow microspheres obtained in S2 were ultrasonically dispersed in the methanol solution, and then a solution containing Hmim was added. After the reaction was completed, the complex was recovered by magnetization. The mixture was washed with water and ethanol alternately until neutral and dried to obtain the Fe3O4 / activated coke@ZIF-67 core-shell material of the present invention.
2. The method for preparing a Fe3O4 / activated coke@ZIF-67 core-shell material according to claim 1, characterized in that: In step S1, the activated coke is pulverized and passed through a 100-200 mesh sieve; the acid solution includes a nitric acid solution with a concentration of 2-5 mol / L; the mass-to-volume ratio of activated coke powder to acid solution is 1:10-20; during thorough mixing, the temperature is 60-80℃, the stirring intensity is 100-200 rpm, and the time is 2-4 h; the mixture is repeatedly washed with deionized water until neutral, and then dried at 105℃ for 8-12 h.
3. The method for preparing a Fe3O4 / activated coke@ZIF-67 core-shell material according to claim 1, characterized in that: In S2, ferric chloride is ferric chloride hexahydrate, trisodium citrate is trisodium citrate dihydrate, and sodium acetate is sodium acetate trihydrate; the mass ratio of ethylene glycol, ferric chloride, trisodium citrate, sodium acetate, and acid-modified activated coke material is 800-1000:20-30:1:50-100:5-15.
4. The method for preparing a Fe3O4 / activated coke@ZIF-67 core-shell material according to claim 3, characterized in that: The ultrasonic dispersion frequency is 20-40kHz, the power is 200-600W, and the dispersion time is 10-30min; the autoclave reaction temperature is 180-220℃, and the reaction time is 10-20h.
5. The method for preparing a Fe3O4 / activated coke@ZIF-67 core-shell material according to claim 4, characterized in that: The water washing uses deionized water and is performed 3 to 5 times; the alcohol washing uses anhydrous ethanol and is performed 1 to 3 times; the vacuum drying temperature is 50 to 80°C and the drying time is 6 to 10 hours.
6. The method for preparing a Fe3O4 / activated coke@ZIF-67 core-shell material according to claim 1, characterized in that: In S3, the mass-to-volume ratio of Fe3O4 hollow microspheres@activated char carrier to methanol is 1:40-60, and the mass ratio of Fe3O4 hollow microspheres@activated char carrier to cobalt nitrate hexahydrate is 1:1-2.
7. The method for preparing a Fe3O4 / activated coke@ZIF-67 core-shell material according to claim 6, characterized in that: The mass ratio of cobalt ions to Hmim is 1:30-50. After adding the solution containing cobalt ions and Hmim, the mixture is reacted at room temperature in a shaking box for 20-30 hours with a shaking frequency of 60-120 rpm and an amplitude of 26 mm.
8. The method for preparing a Fe3O4 / activated coke@ZIF-67 core-shell material according to claim 1, characterized in that: In step S3, the drying temperature is 60–80°C and the drying time is 12–24 hours.
9. The application of the Fe3O4 / activated coke@ZIF-67 core-shell material according to any one of claims 1-8 in the adsorption and removal of antibiotics during wastewater treatment.
10. The application of the Fe3O4 / activated coke@ZIF-67 core-shell material according to claim 9, characterized in that: The Fe3O4 / activated char@ZIF-67 core-shell material described above can adsorb up to 193 mg / g of tetracycline, which is 133 mg / g higher than that of unmodified activated char.