Simple, green and safe nano-zinc oxide preparation method
By using pomegranate peel and zinc nitrate solutions to prepare nano zinc oxide, the problem of complex and unenvironmental preparation process in the prior art is solved, and the simple, green and safe preparation of nano zinc oxide is achieved, and good particles are provided Diameter distribution and electrophoretic performance.
Patent Information
- Application Number
- CN202411601801.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-11
- Publication Date
- 2025-02-18
AI Technical Summary
In the preparation process of existing nano zinc oxide, unsafe reagents are required or carried out under high temperature and high pressure, resulting in complex and unenvironmental processes.
Using pomegranate peel and zinc nitrate solution as raw materials, the active ingredients in pomegranate peel are extracted through deionized water or ethanol solution to react with zinc nitrate solution, and nano zinc oxide is prepared through calcination and washing steps.
It realizes simple, green and safe preparation of nano zinc oxide, with small particle size and low dispersion index, the absolute value of Zeta potential is higher than 30mV, and the process does not require special equipment, it is easy to operate and low energy consumption.
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Figure CN119461462A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of green synthesis of materials, and in particular to a simple, green and safe method for preparing nano zinc oxide. Background Art
[0002] Food and agricultural products are rich in nutrients and are easily contaminated by microorganisms such as Escherichia coli and Staphylococcus aureus. In order to reduce the losses caused by microbial contamination, researchers have developed natural and synthetic antibacterial materials. However, most natural antibacterial agents have defects in heat resistance and durability, and most synthetic antibacterial agents require the use of toxic reagents or consume a lot of energy.
[0003] Zinc oxide nanoparticles (ZnO-NPs) are a common inorganic antimicrobial agent with high thermal stability and strong antimicrobial activity. ZnO-NPs have been shown to effectively kill a large number of microorganisms. Under light, valence band electrons are excited to form electron-hole pairs on the ZnO surface. These electron-hole pairs can undergo redox reactions with water and oxygen to generate reactive oxygen species such as hydroxyl radicals, superoxide anion radicals, singlet oxygen, and hydrogen peroxide. ZnO-NPs are non-toxic and are generally recognized as safe (GRAS) nanomaterials.
[0004] However, in the conventional preparation process of nano zinc oxide, unsafe reagents are often added or the process needs to be carried out under high temperature and high pressure. Therefore, it is urgent to develop a simple, green and safe method for preparing nano zinc oxide. Summary of the invention
[0005] In order to overcome the above-mentioned shortcomings and deficiencies of conventional technologies, the purpose of the present invention is to provide a simple, green and safe method for preparing nano zinc oxide, using pomegranate peel and zinc nitrate solution as raw materials, and other reagents added during the preparation process are only deionized water and ethanol, and no special equipment is required, and the operation is simple; at the same time, the prepared nano zinc oxide has a smaller particle size, a lower PDI, and the absolute value of the Zeta potential is higher than 30mV.
[0006] The purpose of the present invention is achieved through the following technical solutions:
[0007] The present invention provides a simple, green and safe method for preparing nano zinc oxide, comprising the following steps:
[0008] (1) Preparation of pomegranate peel extract:
[0009] The pomegranate peel is washed, dried and crushed to obtain pomegranate peel powder, the pomegranate peel powder is added to deionized water or ethanol solution, and extracted at a temperature of 25 to 80° C. for 1 to 24 hours, and a pomegranate peel extract is obtained after filtering;
[0010] (2) mixing the pomegranate peel extract prepared in step (1) with a zinc nitrate solution, and reacting the mixture at 40 to 100° C. to obtain a nano zinc oxide precursor;
[0011] (3) calcining the nano zinc oxide precursor obtained in step (2) at 200-400° C., washing the product with alcohol and water to remove impurities, and drying to obtain nano zinc oxide.
[0012] Preferably, in step (1), 400 mL of deionized water or ethanol solution is added to every 100 g of pomegranate peel powder.
[0013] Preferably, the concentration of the zinc nitrate solution is 0.08-0.12 mol / L.
[0014] Preferably, the volume ratio of the pomegranate peel extract to the zinc nitrate solution is (1.8-2.2):1.
[0015] Preferably, in step (2), the pomegranate peel extract prepared in step (1) is mixed with a zinc nitrate solution and reacted at 40 to 100° C. to obtain a nano zinc oxide precursor, specifically:
[0016] The pomegranate peel extract prepared in step (1) is mixed with the zinc nitrate solution, reacted at 40-100° C. for 20-40 minutes, and then transferred to a crucible and heated until the water is completely evaporated.
[0017] Preferably, in step (2), the pomegranate peel extract prepared in step (1) is mixed with a zinc nitrate solution and reacted at 40 to 100° C. to obtain a nano zinc oxide precursor, specifically:
[0018] The pomegranate peel extract prepared in step (1) is mixed with the zinc nitrate solution, and the mixture is reacted at 40-60° C. for 0.8-1.2 h. 0.3-0.5 mol / L NaOH is added, and the mixture is stirred for 0.8-1.2 h. The mixture is filtered, and the obtained precipitate is washed with water until it is neutral and then transferred to a crucible.
[0019] Preferably, the extraction temperature in step (1) is 70-80°C.
[0020] Preferably, the reaction in step (2) is specifically: reacting at 80-90° C. for 30-10 min.
[0021] A nano zinc oxide is prepared by the simple, green and safe nano zinc oxide preparation method.
[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:
[0023] (1) The method for preparing nano zinc oxide of the present invention uses pomegranate peel and zinc nitrate solution as raw materials, and other reagents added during the preparation process are only deionized water and ethanol, which has the characteristics of green and safe synthesis.
[0024] (2) In the method for preparing nano zinc oxide of the present invention, the pomegranate extract adopts deionized water or ethanol solution, and the prepared nano zinc oxide has a smaller particle size. Combined with specific preparation process parameters, the embodiment of the present invention can prepare nano zinc oxide with a particle size of 245.98 nm.
[0025] (3) The method for preparing nano zinc oxide of the present invention does not require special equipment or high pressure during the preparation process, is easy to operate, has low energy consumption, and has low production cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 The present invention provides a simple, green and safe method for preparing nano zinc oxide. DETAILED DESCRIPTION
[0027] The present invention will be further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.
[0028] Example 1
[0029] The present invention provides a simple, green and safe method for preparing nano zinc oxide, and its process flow is as follows: Figure 1 As shown, the specific steps are as follows:
[0030] Step 1, preparation of pomegranate peel extract: pomegranate peel (purchased from the local market in Kashgar, Xinjiang) was washed, dried, crushed and passed through an 80-mesh sieve. 100 g was taken and mixed with 400 mL of deionized water. The extraction temperature was 80° C. and the extraction time was 1 h. After filtering, the pomegranate peel aqueous extract was obtained.
[0031] Step 2, preparation of zinc nitrate solution: prepare a zinc nitrate solution with a concentration of 0.1 mol / L using deionized water.
[0032] Step 3: Mix the extract from step 1 and the zinc nitrate solution from step 2 at a ratio of 2:1 (w / v), react at 40°C for 2h, then add 0.4 mol / L NaOH, stir for 1h and filter. Wash the precipitate with water until it is neutral and transfer it to a crucible.
[0033] Step 4: Transfer the crucible in step 3 to a muffle furnace and calcine at 400° C. for 2 h.
[0034] Step 5: The calcined product of step 4 is washed with alcohol and water to remove impurities, and then dried to obtain nano zinc oxide.
[0035] The particle size, dispersion index (PDI) value and Zeta potential of the nano zinc oxide prepared in this example were measured, and the results are shown in Table 1.
[0036] Example 2
[0037] The present invention provides a simple, green and safe method for preparing nano zinc oxide, and its process flow is as follows: Figure 1 As shown, the specific steps are as follows:
[0038] Step 1: Preparation of pomegranate peel extract: Wash, dry and crush pomegranate peel (purchased from a local market in Kashgar, Xinjiang). Take 100 g and mix it with 400 mL of deionized water. The extraction temperature is 70°C and the extraction time is 2 h. After filtering, the pomegranate peel water extract is obtained.
[0039] Step 2, preparation of zinc nitrate solution: prepare a zinc nitrate solution with a concentration of 0.1 mol / L using deionized water.
[0040] Step 3: Mix the extract of step 1 and the zinc nitrate solution of step 2 in a ratio of 2:1 (w / v), react at 90° C. for 40 min, transfer to a crucible and heat until the water is completely evaporated.
[0041] Step 4: Transfer the crucible in step 3 to a muffle furnace and calcine at 400° C. for 2 h.
[0042] Step 5: The calcined product of step 4 is washed with alcohol and water to remove impurities, and then dried to obtain nano zinc oxide.
[0043] The particle size, dispersion index (PDI) value and Zeta potential of the nano zinc oxide prepared in this example were measured, and the results are shown in Table 1.
[0044] Example 3
[0045] The present invention provides a simple, green and safe method for preparing nano zinc oxide, and its process flow is as follows: Figure 1 As shown, the specific steps are as follows:
[0046] Step 1, preparation of pomegranate peel extract: wash, dry and crush pomegranate peel (purchased from a local market in Kashgar, Xinjiang). Take 100 g of pomegranate peel and mix it with 400 mL of deionized water. The extraction temperature is 80° C. and the extraction time is 1 h. After extraction, filter to obtain the pomegranate peel water extract.
[0047] Step 2, preparation of zinc nitrate solution: prepare a zinc nitrate solution with a concentration of 0.1 mol / L using deionized water.
[0048] Step 3: Mix the extract of step 1 and the zinc nitrate solution of step 2 in a ratio of 2:1 (w / v), react at 90° C. for 30 min, transfer to a crucible and heat until the water is completely evaporated.
[0049] Step 4: Transfer the crucible in step 3 to a muffle furnace and calcine at 200° C. for 2 h.
[0050] Step 5: The calcined product of step 4 is washed with alcohol and water to remove impurities, and then dried to obtain nano zinc oxide.
[0051] The particle size, dispersion index (PDI) value and Zeta potential of the nano zinc oxide prepared in this example were measured, and the results are shown in Table 1.
[0052] Example 4
[0053] This comparative example provides a simple, green and safe method for preparing nano zinc oxide, and the specific steps are as follows:
[0054] Step 1, preparation of pomegranate peel extract: pomegranate peel (purchased from the local market in Kashgar, Xinjiang) was washed, dried and crushed. 100 g was taken and mixed with 60% ethanol in a ratio of 1:10 (w / v), and stirred at 30°C for 20 hours. After filtering, the filtrate was vacuum evaporated to remove ethanol to obtain pomegranate peel extract.
[0055] Step 2, preparation of zinc nitrate solution: prepare a zinc nitrate solution with a concentration of 0.1 mol / L using deionized water.
[0056] Step 3: Mix the extract of step 1 and the zinc nitrate solution of step 2 in a ratio of 2:1 (w / v), react at 90° C. for 20 min, transfer to a crucible and heat until the water is completely evaporated.
[0057] Step 4: Transfer the crucible in step 3 to a muffle furnace and calcine at 200° C. for 2 h.
[0058] Step 5: The calcined product of step 4 is washed with alcohol and water to remove impurities, and then dried to obtain zinc oxide.
[0059] The particle size, dispersion index (PDI) value and Zeta potential of the zinc oxide prepared in this comparative example were measured, and the results are shown in Table 1.
[0060] Example 5
[0061] This comparative example provides a simple, green and safe method for preparing nano zinc oxide, and the specific steps are as follows:
[0062] Step 1, preparation of pomegranate peel extract: pomegranate peel (purchased from the local market in Kashgar, Xinjiang) was washed, dried and crushed. 100 g was taken and mixed with 60% ethanol in a ratio of 1:10 (w / v), and stirred at 40°C for 18 hours. After filtering, the filtrate was vacuum evaporated to remove ethanol to obtain pomegranate peel extract.
[0063] Step 2, preparation of zinc nitrate solution: prepare a zinc nitrate solution with a concentration of 0.1 mol / L using deionized water.
[0064] Step 3: Mix the extract from step 1 and the zinc nitrate solution from step 2 at a ratio of 2:1 (w / v), and react at 40°C for 1 hour. Then add 0.4 mol / L NaOH, stir and react for 1 hour, and filter. Wash the precipitate with water until it is neutral and transfer it to a crucible.
[0065] Step 4: Transfer the crucible in step 3 to a muffle furnace and calcine at 400° C. for 2 h.
[0066] Step 5: The calcined product of step 4 is washed with alcohol and water to remove impurities, and then dried to obtain zinc oxide.
[0067] The particle size, dispersion index (PDI) value and Zeta potential of the zinc oxide prepared in this comparative example were measured, and the results are shown in Table 1.
[0068] Example 6
[0069] This comparative example provides a simple, green and safe method for preparing nano zinc oxide, and the specific steps are as follows:
[0070] Step 1, preparation of pomegranate peel extract: pomegranate peel (purchased from the local market in Kashgar, Xinjiang) was washed, dried and crushed. 100 g was taken and mixed with 60% ethanol in a ratio of 1:10 (w / v), and stirred at 25°C for 24 hours. After filtering, the filtrate was vacuum evaporated to remove ethanol to obtain pomegranate peel extract.
[0071] Step 2, preparation of zinc nitrate solution: prepare a zinc nitrate solution with a concentration of 0.1 mol / L using deionized water.
[0072] Step 3: Mix the extract of step 1 and the zinc nitrate solution of step 2 in a ratio of 2:1 (w / v), react at 90° C. for 20 min, transfer to a crucible and heat until the water is completely evaporated.
[0073] Step 4: Transfer the crucible in step 3 to a muffle furnace and calcine at 200° C. for 2 h.
[0074] Step 5: The calcined product of step 4 is washed with alcohol and water to remove impurities, and then dried to obtain zinc oxide.
[0075] The particle size, dispersion index (PDI) value and Zeta potential of the zinc oxide prepared in this comparative example were measured, and the results are shown in Table 1.
[0076] Example 7
[0077] This comparative example provides a simple, green and safe method for preparing nano zinc oxide, and the specific steps are as follows:
[0078] Step 1, preparation of pomegranate peel extract: pomegranate peel (purchased from the local market in Kashgar, Xinjiang) was washed, dried and crushed. 100 g was taken and mixed with 60% ethanol in a ratio of 1:10 (w / v), and stirred at 35°C for 22 hours. After filtering, the filtrate was vacuum evaporated to remove ethanol to obtain pomegranate peel extract.
[0079] Step 2, preparation of zinc nitrate solution: prepare a zinc nitrate solution with a concentration of 0.1 mol / L using deionized water.
[0080] Step 3: Mix the extract of step 1 and the zinc nitrate solution of step 2 in a ratio of 2:1 (w / v), react at 90° C. for 20 min, transfer to a crucible and heat until the water is completely evaporated.
[0081] Step 4: Transfer the crucible in step 3 to a muffle furnace and calcine at 400° C. for 2 h.
[0082] Step 5: The calcined product of step 4 is washed with alcohol and water to remove impurities, and then dried to obtain nano zinc oxide.
[0083] The particle size, dispersion index (PDI) value and Zeta potential of the nano zinc oxide prepared in this comparative example were measured, and the results are shown in Table 1.
[0084] Table 1
[0085] Particle size (nm) PDI Zeta potential (mV) Example 1 436.63 0.264 -38.33 Example 2 284.23 0.267 -38.39 Example 3 245.98 0.174 -35.17 Example 4 9345.51 0.448 -44.28 Example 5 1090.88 0.271 -38.34 Example 6 8066.70 0.393 -30.08 Example 7 486.31 0.295 -38.27
[0086] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.
Claims
1. A simple, green and safe method for preparing nano zinc oxide, characterized in that: The following steps are involved: (1) Preparation of pomegranate peel extract: The pomegranate peel is washed, dried and crushed to obtain pomegranate peel powder, the pomegranate peel powder is added to deionized water or ethanol solution, and extracted at a temperature of 25 to 80° C. for 1 to 24 hours, and a pomegranate peel extract is obtained after filtering; (2) mixing the pomegranate peel extract prepared in step (1) with a zinc nitrate solution, and reacting the mixture at 40 to 100° C. to obtain a nano zinc oxide precursor; (3) calcining the nano zinc oxide precursor obtained in step (2) at 200-400° C., washing the product with alcohol and water to remove impurities, and drying to obtain nano zinc oxide.
2. The simple, green and safe method for preparing nano zinc oxide according to claim 1, characterized in that: In step (1), 400 mL of deionized water is added to every 100 g of pomegranate peel powder.
3. The simple, green and safe method for preparing nano zinc oxide according to claim 2, characterized in that: The concentration of the zinc nitrate solution is 0.08-0.12 mol / L.
4. The simple, green and safe method for preparing nano zinc oxide according to claim 3, characterized in that: The volume ratio of the pomegranate peel extract to the zinc nitrate solution is (1.8-2.2):
1.
5. The simple, green and safe method for preparing nano zinc oxide according to claim 1, characterized in that: In step (2), the pomegranate peel extract prepared in step (1) is mixed with zinc nitrate solution and reacted at 40-100° C. to obtain a nano zinc oxide precursor, specifically: The pomegranate peel extract prepared in step (1) is mixed with the zinc nitrate solution, reacted at 40-100° C. for 20-40 minutes, and then transferred to a crucible and heated until the water is completely evaporated.
6. The simple, green and safe method for preparing nano zinc oxide according to claim 1, characterized in that: In step (2), the pomegranate peel extract prepared in step (1) is mixed with zinc nitrate solution and reacted at 40-100° C. to obtain a nano zinc oxide precursor, specifically: The pomegranate peel extract prepared in step (1) is mixed with the zinc nitrate solution, and the mixture is reacted at 40-60° C. for 0.8-1.2 h. 0.3-0.5 mol / L NaOH is added, and the mixture is stirred for 0.8-1.2 h. The mixture is filtered, and the obtained precipitate is washed with water until it is neutral and then transferred to a crucible.
7. The simple, green and safe method for preparing nano zinc oxide according to claim 1, characterized in that: The extraction temperature in step (1) is 70-80°C.
8. The simple, green and safe method for preparing nano zinc oxide according to claim 7, characterized in that: The reaction in step (2) is specifically: reacting at 80-90° C. for 30-10 minutes.
9. A nano zinc oxide, characterized in that: The nano zinc oxide is prepared by the simple, green and safe preparation method of any one of claims 1 to 8.