Fertilizer added with vitamin B12 and preparation method thereof

Abstract

The invention relates to the technical field of fertilizers, in particular to a fertilizer added with vitamin B12 and a preparation method of the fertilizer. 1 to 20 parts of coconut shell; 1 to 20 parts of hydrogel; 8 to 18 parts of humic acid; 2 to 10 parts of cyclodextrin; 1-8 parts of a chelating agent; 1-6 parts of trace elements; 5 to 15 parts of a microbial agent; and 0.01 to 0.3 part of vitamin B12. According to the invention, the urea is modified through accurate proportioning, so that slow release and accurate supply of the urea are realized, the nitrogen loss is effectively reduced, and the utilization efficiency of the nitrogen fertilizer is improved. Meanwhile, hydrogel with temperature-sensitive characteristics is added, and the hydrogel can adjust swelling and shrinkage according to different temperature environments, maintain soil moisture and provide good conditions for microbial activity and fertilizer nutrient dissolution. Sensitive nutritional ingredients such as vitamin B12 are included by utilizing a special structure of cyclodextrin, the ingredients are effectively protected from being damaged, and through precise release, the growth and development of plants are promoted, and the quality and yield of crops are improved.

Description

Technical Field

[0001] The present invention relates to the field of fertilizers, and particularly to a fertilizer containing vitamin B12 and a preparation method thereof. Background Art

[0002] With the development of agricultural modernization, the requirements for fertilizers are getting higher and higher. It is not only expected that fertilizers can provide the basic nutrient elements required for plant growth, but also hoped that they have various functions such as promoting plant growth and enhancing plant stress resistance. As a biologically active substance, vitamin B12 has a certain promoting effect on the growth and development of plants. It can participate in various physiological and biochemical processes in plants, such as promoting the growth of plant roots, improving the photosynthesis efficiency of plants, and enhancing the resistance of plants to pests and diseases.

[0003] However, most of the fertilizers on the market at present only focus on the addition of conventional nutrient elements such as nitrogen, phosphorus, and potassium, and rarely effectively combine vitamin B12 with fertilizers. Even if some products add vitamin B12, there are still many problems in their preparation methods. For example, the stability of vitamin B12 in fertilizers is poor and it is easy to inactivate during storage or use; the preparation process is complex, resulting in high production costs and it is difficult to be popularized and applied on a large scale. Summary of the Invention

[0004] The present application provides a fertilizer containing vitamin B12 and a preparation method thereof to solve the problems such as poor stability, complex preparation process and high cost of fertilizers containing vitamin B12 in the related art.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows: The present invention provides a fertilizer containing vitamin B12, and the fertilizer is composed of the following weight ratio components: Modified urea: 20 - 40 parts; Coconut shell: 1 - 20 parts; Hydrogel: 1 - 20 parts; Humic acid: 8 - 18 parts; Cyclodextrin: 2 - 10 parts; Chelating agent: 1 - 8 parts; Trace elements: 1 - 6 parts; Microbial inoculum: 5 - 15 parts; Vitamin B12: 0.01 - 0.3 parts.

[0006] Further, the fertilizer is composed of the following weight ratio components: Modified urea: 25 - 35 parts; Coconut shell: 10 - 18 parts; Hydrogel: 8 - 15 parts; Humic acid: 10 - 16 parts; Cyclodextrin: 4 - 8 parts; Chelating agent: 3 - 6 parts; Trace elements: 2 - 5 parts; Microbial inoculant: 5 - 10 parts; Vitamin B12: 0.05 - 0.2 parts.

[0007] Furthermore, the modified urea is composed of the following components in parts by weight: Urea: 70 - 90 parts; 3D - MXene: 5 - 15 parts; MOFs: 3 - 10 parts.

[0008] Furthermore, the sheet thickness of the 3D - MXene is 1 - 5 nm, and its specific surface area is not less than 200 m² / g.

[0009] Furthermore, the MOFs are metal - organic framework materials based on zinc, iron or copper, and their pore size is 0.5 - 2 nm.

[0010] Furthermore, the microbial inoculant contains nitrogen - fixing bacteria, phosphorus - solubilizing bacteria and potassium - solubilizing bacteria. Among them, the effective viable count of the nitrogen - fixing bacteria is not less than 1×10 8 CFU / g, the effective viable count of the phosphorus - solubilizing bacteria is not less than 5×10 7 CFU / g, and the effective viable count of the potassium - solubilizing bacteria is not less than 8×10 7 CFU / g.

[0011] Furthermore, the hydrogel is a mixture of N - isopropylacrylamide, N - isopropylacrylamide and nano - zinc oxide.

[0012] Furthermore, the trace elements include iron, zinc, manganese, boron, copper, and the weight ratio between the trace elements is 2 - 5:1 - 3:1 - 2:0.5 - 1.5:0.1 - 0.5.

[0013] Furthermore, the chelating agent is a mixture of disodium ethylenediaminetetraacetate and amino acid chelating agent in a weight ratio of 1:1 - 3:1, and the cyclodextrin is a composite cyclodextrin composed of β - cyclodextrin and hydroxypropyl - β - cyclodextrin in a weight ratio of 2:1 - 5:1.

[0014] The present invention also provides a preparation method of a fertilizer added with vitamin B12, including: Raw material pretreatment: The pretreatment includes preparing a modified urea premix, carbonizing coconut shell, preparing hydrogel, grinding and screening humic acid, preparing a chelating agent, a composite cyclodextrin and a trace element solution, and activating the microbial inoculant into a suspension; Mixing granulation: first add the modified urea premix to the mixer and stir, then add the pretreated raw materials, then add the microbial agent suspension and vitamin B12 and stir, and then send the materials into the granulator to form 2-5 mm particles; Post-processing: vacuum drying is used to reduce the moisture content of the particles to 5%-8%, and a vibrating screen is used to screen out qualified particles of 2-5 mm.

[0015] The beneficial effects achieved by adopting the above-mentioned present invention are as follows: 1. The present invention prepares a fertilizer with added vitamin B12, wherein the modified urea in the fertilizer is carefully synthesized from urea, 3D-MXene and MOFs according to precise proportions, wherein the ultra-thin sheets and huge specific surface area of ​​3D-MXene can adsorb and wrap urea molecules, forming a physical barrier, slowing down the dissolution and release rate of urea; there is a strong interaction between urea molecules and the active groups on the surface of 3D-MXene, including van der Waals forces and hydrogen bonds, etc., which make the urea molecules firmly attached to the surface of the 3D-MXene sheets and difficult to fall off easily. At the same time, the MOFs material, with its highly ordered and appropriately sized pore structure, further adsorbs, stores and slowly releases urea molecules. When urea molecules approach MOFs, their pore size perfectly matches that of urea molecules. Driven by intermolecular forces, urea molecules smoothly enter the pores of MOFs and achieve temporary storage. This not only further fine-tunes the release rate of urea, enabling it to more accurately meet the nitrogen needs of plants during their growth cycle, but also significantly reduces nitrogen leaching and volatilization, thereby greatly improving the utilization efficiency of nitrogen fertilizers. 2. The hydrogel prepared by the present invention has a temperature-sensitive property. Its hydrophilicity will change under different temperature environments, thereby adjusting its own swelling and shrinkage. This is based on the amide group in its molecular structure, which will affect the formation and breaking of intramolecular and intermolecular hydrogen bonds when the temperature changes, thereby changing the physical state of the hydrogel. When the soil temperature is suitable for plant growth, the hydrogel absorbs water and expands. On the one hand, it locks in moisture, providing a good environment for microbial activity and fertilizer nutrient dissolution; on the other hand, its internal network structure can adsorb and temporarily store nutrient ions in the fertilizer, playing a role in slow and controlled release; 3. Secondly, zinc oxide is coated on the surface of the hydrogel. On the one hand, nano-zinc oxide has certain photocatalytic activity. Under light illumination, it can generate reactive oxygen species with strong oxidizing properties, such as hydroxyl radicals and superoxide anions. These reactive oxygen species can inhibit harmful microorganisms on the surface of the hydrogel and in the surrounding environment, reduce the decomposition and consumption of fertilizer nutrients by microorganisms, and ensure the long-term supply of fertilizer nutrients. On the other hand, the surface of zinc oxide carries certain charges, which can undergo electrostatic adsorption with some charged particles in the soil, making the hydrogel better dispersed in the soil and less likely to agglomerate. Thus, it is more evenly distributed between soil particles, ensuring the stable exertion of its sustained and controlled release function. In addition, zinc oxide can also serve as a source of trace element supplementation. As the hydrogel swells and degrades, zinc ions are slowly released, providing the essential zinc nutrient element for plant growth, further promoting the healthy development of plants, synergistically enhancing the quality and fertilizer efficiency of the fertilizer with other components in the fertilizer, and comprehensively improving the quality and fertilizer efficiency of the fertilizer.

[0016] 4. The present invention also adds cyclodextrin. Utilizing the special cavity structure with a hydrophobic interior and a hydrophilic exterior of cyclodextrin, it encapsulates easily oxidized and decomposed nutrient components such as vitamin B12. The hydrophobic groups in the vitamin B12 molecule are attracted to the hydrophobic environment inside the cyclodextrin cavity and thus embed therein, protecting them from the invasion of microorganisms and oxidizing substances in the soil. With the action of substances secreted by plant roots and metabolites of soil microorganisms, cyclodextrin slowly releases vitamin B12. Some organic acids secreted by plant roots and enzyme substances produced by microbial metabolism can interact with cyclodextrin molecules, disrupting the weak interaction between cyclodextrin and vitamin B12, enabling vitamin B12 to be released, precisely acting on plant roots, participating in physiological processes such as plant cell division and photosynthesis, promoting plant growth and development, and improving the quality and yield of crops. 5. The entire preparation process of the present invention reduces labor costs, equipment losses, and material waste through precise optimization measures, effectively controlling production costs, making the fertilizer of the present invention more competitive in the market. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, wherein: Figure 1 It is a scanning electron microscope image of the hydrogel provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The technical solutions of the present invention are described below through specific specific examples. It should be understood that one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combined steps or the insertion of other method steps between these clearly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. Moreover, unless otherwise stated, the numbers of the method steps are only convenient tools for identifying the method steps, rather than limiting the arrangement order of the method steps or the scope in which the present invention can be implemented. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope in which the present invention can be implemented.

[0019] To better understand the above technical solutions, the exemplary embodiments of the present invention are described in more detail below. Although the 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 to enable a more thorough understanding of the present invention and to be able to fully convey the scope of the present invention to those skilled in the art.

[0020] The present invention is further described below in conjunction with the following embodiments.

[0021] Example 1 A fertilizer added with vitamin B12, and the fertilizer is composed of the following weight parts: Modified urea: 25 parts; Coconut shell: 10 parts; Hydrogel: 8 parts; Humic acid: 10 parts; Cyclodextrin: 4 parts; Chelating agent: 3 parts; Trace elements: 2 parts; Microbial inoculum: 5 parts; Vitamin B12: 0.05 part.

[0022] In the embodiment of the present application, the modified urea is composed of the following weight parts: Urea: 70 parts; 3D-MXene: 5 parts; MOFs: 3 parts.

[0023] In the embodiment of the present application, the sheet thickness of 3D-MXene is 1-5 nm, and its specific surface area is not less than 200 m² / g.

[0024] In the embodiment of the present application, MOFs are metal-organic framework materials based on zinc, iron or copper, and their pore diameters are 0.5-2 nm.

[0025] In the embodiments of the present application, the microbial inoculant includes nitrogen-fixing bacteria, phosphorus-solubilizing bacteria, and potassium-solubilizing bacteria. Among them, the effective viable count of nitrogen-fixing bacteria is not less than 1×10 8 CFU / g, the effective viable count of phosphorus-solubilizing bacteria is not less than 5×10 7 CFU / g, and the effective viable count of potassium-solubilizing bacteria is not less than 8×10 7 CFU / g.

[0026] In the embodiments of the present application, as Figure 1 shown, the hydrogel is a mixture of N-isopropylacrylamide, N-isopropylacrylamide, and nano-zinc oxide.

[0027] In the embodiments of the present application, the trace elements include iron, zinc, manganese, boron, and copper, and the weight ratio between the trace elements is 2:1:1:0.5:0.1.

[0028] In the embodiments of the present application, the chelating agent is a mixture of disodium ethylenediaminetetraacetate and amino acid chelating agent in a weight ratio of 1:1:1, and the cyclodextrin is a composite cyclodextrin composed of β-cyclodextrin and hydroxypropyl-β-cyclodextrin in a weight ratio of 2:1:1.

[0029] A preparation method of a fertilizer added with vitamin B12, the preparation method includes: Raw material pretreatment: The pretreatment includes preparing a modified urea premix, carbonizing coconut shells, preparing a hydrogel, grinding and screening humic acid, preparing a chelating agent, a composite cyclodextrin, and a trace element solution, and activating the microbial inoculant into a suspension; Mixing and granulating: First, add the modified urea premix to a mixer and stir, then add the pretreated raw materials, then add the microbial inoculant suspension and vitamin B12 and stir, and send the material to a granulator to make 2-5 mm particles; Post-treatment: Use vacuum drying to reduce the water content of the particles to 5%-8%, and screen the 2-5 mm qualified particles with a vibrating screen.

[0030] Example 2 A preparation method of a fertilizer added with vitamin B12, the fertilizer is composed of the following weight parts: Modified urea: 27 parts; Coconut shell: 12 parts; Hydrogel: 10 parts; Humic acid: 11 parts; Cyclodextrin: 5 parts; Chelating agent: 4 parts; Trace elements: 3 parts; Microbial inoculant: 6 parts; Vitamin B12: 0.09 part.

[0031] In the embodiments of the present application, the modified urea is composed of the following weight proportions: Urea: 75 parts; 3D-MXene: 7 parts; MOFs: 5 parts.

[0032] In the embodiments of the present application, the sheet thickness of 3D-MXene is 1 - 5 nm, and its specific surface area is not less than 200 m² / g.

[0033] In the embodiments of the present application, MOFs are metal-organic framework materials based on zinc, iron or copper, and their pore size is 0.5 - 2 nm.

[0034] In the embodiments of the present application, the microbial inoculant contains nitrogen-fixing bacteria, phosphorus-solubilizing bacteria and potassium-solubilizing bacteria. Among them, the effective viable count of nitrogen-fixing bacteria is not less than 1×10 8 CFU / g, the effective viable count of phosphorus-solubilizing bacteria is not less than 5×10 7 CFU / g, and the effective viable count of potassium-solubilizing bacteria is not less than 8×10 7 CFU / g.

[0035] In the embodiments of the present application, as Figure 1 shown, the hydrogel is a mixture of N-isopropylacrylamide, N-isopropylacrylamide and nano-zinc oxide.

[0036] In the embodiments of the present application, the trace elements include iron, zinc, manganese, boron, copper, and the weight ratio between each trace element is 3:1.5:1.2:0.7:0.2.

[0037] In the embodiments of the present application, the chelating agent is a mixture of disodium ethylenediaminetetraacetate and amino acid chelating agent in a weight ratio of 1:1.5:1, and the cyclodextrin is a composite cyclodextrin composed of β-cyclodextrin and hydroxypropyl-β-cyclodextrin in a weight ratio of 2:2:1.

[0038] A preparation method of a fertilizer added with vitamin B12, the preparation method includes: Raw material pretreatment: The pretreatment includes preparing a modified urea premix, carbonizing coconut shell, preparing hydrogel, grinding and screening humic acid, preparing a chelating agent, a composite cyclodextrin and a trace element solution, and activating the microbial inoculant into a suspension; Mixing and granulating: First add the modified urea premix to a mixer and stir, then add the pretreated raw materials, then add the microbial inoculant suspension and vitamin B12 and stir, and send the material into a granulator to make 2 - 5 mm particles; Post-treatment: Use vacuum drying to reduce the water content of the particles to 5% - 8%, and screen the 2 - 5 mm qualified particles with a vibrating screen.

[0039] Example 3 Preparation method of a fertilizer added with vitamin B12, the fertilizer is composed of the following weight parts: Modified urea: 30 parts; Coconut shell: 14 parts; Hydrogel: 12 parts; Humic acid: 13 parts; Cyclodextrin: 6 parts; Chelating agent: 4.5 parts; Trace elements: 3.5 parts; Microbial inoculum: 7 parts; Vitamin B12: 0.13 part.

[0040] In the embodiment of the present application, the modified urea is composed of the following weight parts: Urea: 80 parts; 3D-MXene: 10 parts; MOFs: 7 parts.

[0041] In the embodiment of the present application, the sheet thickness of 3D-MXene is 1-5 nm, and its specific surface area is not less than 200 m² / g.

[0042] In the embodiment of the present application, the MOFs are metal-organic framework materials based on zinc, iron or copper, and their pore size is 0.5-2 nm.

[0043] In the embodiment of the present application, the microbial inoculum contains nitrogen-fixing bacteria, phosphorus-solubilizing bacteria and potassium-solubilizing bacteria. Among them, the effective viable count of nitrogen-fixing bacteria is not less than 1×10 8 CFU / g, the effective viable count of phosphorus-solubilizing bacteria is not less than 5×10 7 CFU / g, and the effective viable count of potassium-solubilizing bacteria is not less than 8×10 7 CFU / g.

[0044] In the embodiment of the present application, as Figure 1 shown, the hydrogel is a mixture of N-isopropylacrylamide, N-isopropylacrylamide and nano-zinc oxide.

[0045] In the embodiment of the present application, the trace elements contain iron, zinc, manganese, boron, copper, and the weight ratio between the trace elements is 3.5:2:1.5:1:0.3.

[0046] In the embodiment of the present application, the chelating agent is a mixture of disodium ethylenediaminetetraacetate and amino acid chelating agent in a weight ratio of 1:2:1, and the cyclodextrin is a composite cyclodextrin composed of β-cyclodextrin and hydroxypropyl-β-cyclodextrin in a weight ratio of 2:3:1.

[0047] A preparation method of a fertilizer added with vitamin B12, the preparation method includes: Raw material pretreatment: The pretreatment includes preparing a modified urea premix, carbonizing coconut shells, preparing hydrogels, grinding and screening humic acid, preparing chelating agents, composite cyclodextrin and trace element solutions, and activating microbial agents into suspensions; Mixing and granulation: First, add the modified urea premix to a mixer and stir, then add the pretreated raw materials, and then add the microbial agent suspension and vitamin B12 and stir. Feed the material into a granulator to make 2-5 mm particles; Post-treatment: Use vacuum drying to reduce the water content of the particles to 5%-8%, and use a vibrating screen to screen qualified 2-5 mm particles.

[0048] Example 4 A preparation method of a fertilizer added with vitamin B12, and the fertilizer is composed of the following weight ratio components: Modified urea: 32 parts; Coconut shell: 16 parts; Hydrogel: 14 parts; Humic acid: 15 parts; Cyclodextrin: 7 parts; Chelating agent: 5 parts; Trace elements: 4 parts; Microbial agent: 8 parts; Vitamin B12: 0.17 part.

[0049] In the embodiment of the present application, the modified urea is composed of the following weight ratio components: Urea: 85 parts; 3D-MXene: 12 parts; MOFs: 9 parts.

[0050] In the embodiment of the present application, the sheet thickness of 3D-MXene is 1-5 nm, and its specific surface area is not less than 200 m² / g.

[0051] In the embodiment of the present application, MOFs are metal-organic framework materials based on zinc, iron or copper, and their pore diameters are 0.5-2 nm.

[0052] In the embodiment of the present application, the microbial agent includes nitrogen-fixing bacteria, phosphorus-solubilizing bacteria and potassium-solubilizing bacteria. Among them, the effective viable count of nitrogen-fixing bacteria is not less than 1×10 8 CFU / g, the effective viable count of phosphorus-solubilizing bacteria is not less than 5×10 7 CFU / g, and the effective viable count of potassium-solubilizing bacteria is not less than 8×10 7 CFU / g.

[0053] In the embodiment of the present application, as Figure 1 shown, the hydrogel is a mixture of N-isopropylacrylamide, N-isopropylacrylamide and nano-zinc oxide.

[0054] In the embodiment of the present application, the trace elements include iron, zinc, manganese, boron, and copper, and the weight ratio between the trace elements is 4:2.5:1.8:1.2:0.4.

[0055] In the embodiment of the present application, the chelating agent is a mixture of disodium ethylenediaminetetraacetate and amino acid chelating agent in a weight ratio of 1:2.5:1, and the cyclodextrin is a composite cyclodextrin composed of β-cyclodextrin and hydroxypropyl-β-cyclodextrin in a weight ratio of 2:4:1.

[0056] A preparation method of a fertilizer added with vitamin B12, the preparation method comprising: Raw material pretreatment: The pretreatment includes preparing a modified urea premix, carbonizing coconut shells, preparing hydrogels, grinding and screening humic acid, preparing a chelating agent, a composite cyclodextrin and a trace element solution, and activating the microbial inoculant into a suspension; Mixing and granulating: First add the modified urea premix to a mixer and stir, then add the pretreated raw materials, then add the microbial inoculant suspension and vitamin B12 and stir, and send the material to a granulator to make 2-5 mm particles; Post-treatment: Use vacuum drying to reduce the water content of the particles to 5%-8%, and screen the 2-5 mm qualified particles with a vibrating screen.

[0057] Example 5 A preparation method of a fertilizer added with vitamin B12, the fertilizer is composed of the following weight parts: Modified urea: 35 parts; Coconut shell: 18 parts; Hydrogel: 15 parts; Humic acid: 16 parts; Cyclodextrin: 8 parts; Chelating agent: 6 parts; Trace elements: 5 parts; Microbial inoculant: 10 parts; Vitamin B12: 0.2 part.

[0058] In the embodiment of the present application, the modified urea is composed of the following weight parts: Urea: 90 parts; 3D-MXene: 15 parts; MOFs: 10 parts.

[0059] In the embodiment of the present application, the sheet thickness of 3D-MXene is 1-5 nm, and its specific surface area is not less than 200 m² / g.

[0060] In the embodiment of the present application, MOFs are metal-organic framework materials based on zinc, iron or copper, and their pore size is 0.5-2 nm.

[0061] In the embodiments of the present application, the microbial inoculum comprises nitrogen-fixing bacteria, phosphorus-solubilizing bacteria, and potassium-solubilizing bacteria. Among them, the effective viable count of the nitrogen-fixing bacteria is not less than 1×10 8 CFU / g, the effective viable count of the phosphorus-solubilizing bacteria is not less than 5×10 7 CFU / g, and the effective viable count of the potassium-solubilizing bacteria is not less than 8×10 7 CFU / g.

[0062] In the embodiments of the present application, as Figure 1 shown, the hydrogel is a mixture of N-isopropylacrylamide, N-isopropylacrylamide, and nano-zinc oxide.

[0063] In the embodiments of the present application, the trace elements include iron, zinc, manganese, boron, and copper, and the weight ratio between the trace elements is 5:3:2:1.5:0.5.

[0064] In the embodiments of the present application, the chelating agent is formed by mixing disodium ethylenediaminetetraacetate and amino acid chelating agent in a weight ratio of 1:3:1, and the cyclodextrin is a composite cyclodextrin composed of β-cyclodextrin and hydroxypropyl-β-cyclodextrin in a weight ratio of 2:5:1.

[0065] A preparation method of a fertilizer added with vitamin B12, the preparation method comprising: Raw material pretreatment: The pretreatment includes preparing a modified urea premix, carbonizing coconut shells, preparing a hydrogel, grinding and screening humic acid, preparing a chelating agent, a composite cyclodextrin, and a trace element solution, and activating the microbial inoculum into a suspension; Mixing and granulating: First, add the modified urea premix to a mixer and stir, then add the pretreated raw materials, then add the microbial inoculum suspension and vitamin B12 and stir, and send the material to a granulator to make 2-5 mm particles; Post-treatment: Use vacuum drying to reduce the water content of the particles to 5%-8%, and screen the 2-5 mm qualified particles with a vibrating screen.

[0066] Comparative Example 1 A fertilizer added with vitamin B12, which is different from Example 1 only in that the modified urea does not contain 3D-MXene, and the reduction amount of 3D-MXene is allocated to urea, and the other components are the same as those in Example 1.

[0067] Comparative Example 2 A fertilizer added with vitamin B12, which is different from Example 1 only in that the fertilizer does not contain a hydrogel, and the reduction amount of the hydrogel is allocated to humic acid, and the other components are the same as those in Example 1.

[0068] Comparative Example 3 A fertilizer added with vitamin B12, which is only different from Example 1 in that the modified urea does not contain 3D-MXene and the fertilizer does not contain hydrogel. The reduced amount of 3D-MXene is allocated to urea, and the reduced amount of hydrogel is allocated to humic acid, and the other components are the same as those in Example 1.

[0069] Performance test The fertilizer samples of Examples 1-5 and Comparative Examples 1-3 were respectively placed in a simulated soil leaching device, and the leaching solution was collected at certain time intervals. The nitrogen content in the leaching solution was measured by the Kjeldahl method. The results showed that: Example 1: Within 0-7 days, the cumulative nitrogen release rate was about 10%, about 15% from 7-14 days, about 20% from 14-21 days, about 22% from 21-28 days, about 18% from 28-35 days, about 10% from 35-42 days, about 3% from 42-49 days, and about 2% from 49-56 days, showing a trend of slow release in the early stage, stable release in the middle stage, and slow decrease in the later stage, which was more in line with the demand law of nitrogen for the plant growth cycle.

[0070] Example 2: The cumulative nitrogen release rate from 0-7 days was about 12%, about 16% from 7-14 days, about 22% from 14-21 days, about 24% from 21-28 days, about 16% from 28-35 days, about 8% from 35-42 days, about 2% from 42-49 days, and about 1% from 49-56 days. The release law was similar to that of Example 1 and there were slight differences in the release rate, which benefited from its optimized raw material ratio.

[0071] Example 3: The cumulative nitrogen release rates at the corresponding stages were about 14% from 0-7 days, about 18% from 7-14 days, about 24% from 14-21 days, about 26% from 21-28 days, about 14% from 28-35 days, about 6% from 35-42 days, about 1% from 42-49 days, and about 0.5% from 49-56 days. The continuous optimization of the ratio made the nitrogen release more accurate and efficient.

[0072] Example 4: In the early stage, it was about 16% from 0-7 days, about 20% from 7-14 days, about 26% from 14-21 days, about 28% from 21-28 days, about 12% from 28-35 days, about 4% from 35-42 days, about 0.5% from 42-49 days, and about 0.3% from 49-56 days. The release curve became smoother and met the long-term needs of plants.

[0073] Example 5: It was about 18% from 0-7 days, about 22% from 7-14 days, about 28% from 14-21 days, about 30% from 21-28 days, about 10% from 28-35 days, about 2% from 35-42 days, about 0.3% from 42-49 days, and about 0.2% from 49-56 days, achieving a good nitrogen slow-release effect.

[0074] Comparative Example 1: Due to the lack of 3D-MXene, the cumulative nitrogen release rate was as high as 30% within 0-7 days, with too rapid release in the early stage. Subsequently, it was approximately 20% from 7-14 days, about 15% from 14-21 days, around 10% from 21-28 days, about 8% from 28-35 days, approximately 5% from 35-42 days, about 1% from 42-49 days, and around 0.5% from 49-56 days. It could not accurately match the plant growth requirements and was prone to nitrogen loss and waste.

[0075] Comparative Example 2: When the hydrogel was absent, the cumulative nitrogen release rate was about 25% within 0-7 days, around 20% from 7-14 days, approximately 18% from 14-21 days, about 12% from 21-28 days, around 8% from 28-35 days, approximately 4% from 35-42 days, about 0.5% from 42-49 days, and around 0.3% from 49-56 days. The release in the early stage was also relatively fast, and the stability in the middle stage was poor.

[0076] Comparative Example 3: Without both 3D-MXene and hydrogel, the cumulative nitrogen release rate was as high as 35% within 0-7 days, and the release rates in subsequent stages were disordered. For example, it was about 22% from 7-14 days, approximately 12% from 14-21 days, around 8% from 21-28 days, about 6% from 28-35 days, approximately 3% from 35-42 days, about 0.5% from 42-49 days, and around 0.2% from 49-56 days. The overall nitrogen release performance was extremely poor.

[0077] Trace element release monitoring: The content of trace elements released from the fertilizer in the soil was regularly detected by inductively coupled plasma optical emission spectrometry, and the determination was also carried out at time intervals. Taking zinc element as an example: Example 1: Within 0-7 days, the cumulative zinc release rate was about 8%, around 12% from 7-14 days, approximately 18% from 14-21 days, about 22% from 21-28 days, around 20% from 28-35 days, approximately 15% from 35-42 days, about 8% from 42-49 days, and around 3% from 49-56 days, showing a relatively stable trend and being coordinated with the nitrogen release, meeting the zinc requirements of plants at different growth stages.

[0078] Example 2: The cumulative zinc release rate within 0-7 days was about 10%, around 14% from 7-14 days, approximately 20% from 14-21 days, about 24% from 21-28 days, around 18% from 28-35 days, approximately 12% from 35-42 days, about 6% from 42-49 days, and around 2% from 49-56 days. The release pattern was adapted to the plant growth rhythm.

[0079] Example 3: The cumulative release rates of zinc element at corresponding stages are approximately 12% from 0 to 7 days, approximately 16% from 7 to 14 days, approximately 22% from 14 to 21 days, approximately 26% from 21 to 28 days, approximately 16% from 28 to 35 days, approximately 10% from 35 to 42 days, approximately 4% from 42 to 49 days, and approximately 1% from 49 to 56 days. Continuously optimizing the ratio ensures the precise release of trace elements.

[0080] Example 4: In the early stage, it is approximately 14% from 0 to 7 days, approximately 18% from 7 to 14 days, approximately 24% from 14 to 21 days, approximately 28% from 21 to 28 days, approximately 14% from 28 to 35 days, approximately 8% from 35 to 42 days, approximately 2% from 42 to 49 days, and approximately 0.5% from 49 to 56 days. The release curve becomes increasingly stable, facilitating the healthy growth of plants.

[0081] Example 5: It is approximately 16% from 0 to 7 days, approximately 20% from 7 to 14 days, approximately 26% from 14 to 21 days, approximately 30% from 21 to 28 days, approximately 12% from 28 to 35 days, approximately 6% from 35 to 42 days, approximately 1% from 42 to 49 days, and approximately 0.3% from 49 to 56 days, achieving a good slow-release effect of trace elements.

[0082] Comparative Example 1: Without the influence of 3D-MXene, the cumulative release rate of zinc element within 0 to 7 days is as high as 25%. The release in the early stage is too rapid, and then it is approximately 18% from 7 to 14 days, approximately 12% from 14 to 21 days, approximately 8% from 21 to 28 days, approximately 6% from 28 to 35 days, approximately 4% from 35 to 42 days, approximately 1% from 42 to 49 days, and approximately 0.5% from 49 to 56 days. It cannot cooperate with plant growth and is prone to causing trace element imbalance.

[0083] Comparative Example 2: Without the hydrogel, the cumulative release rate of zinc element is approximately 20% from 0 to 7 days, approximately 16% from 7 to 14 days, approximately 14% from 14 to 21 days, approximately 10% from 21 to 28 days, approximately 8% from 28 to 35 days, approximately 4% from 35 to 42 days, approximately 0.5% from 42 to 49 days, and approximately 0.3% from 49 to 56 days. The release in the early stage is relatively fast, and the stability in the middle stage is insufficient.

[0084] Comparative Example 3: Without both 3D-MXene and hydrogel, the cumulative release rate of zinc element is as high as 30% from 0 to 7 days, and the release rates in subsequent stages are disordered. For example, it is approximately 20% from 7 to 14 days, approximately 10% from 14 to 21 days, approximately 6% from 21 to 28 days, approximately 4% from 28 to 35 days, approximately 2% from 35 to 42 days, approximately 0.5% from 42 to 49 days, and approximately 0.2% from 49 to 56 days. The overall trace element release performance is poor.

[0085] In summary, the present invention provides a fertilizer added with vitamin B12 and its preparation method, achieving the stable release and efficient utilization of nitrogen, trace elements, and vitamin B12. In the nitrogen release characteristic test, Examples 1-5 showed a slow-release effect highly consistent with the plant growth cycle, slow in the early stage, stable in the middle stage, and slowly decreasing in the later stage, avoiding the rapid loss of nitrogen or insufficient supply in the early stage. As key components, 3D-MXene and hydrogel effectively regulate the nitrogen release stability through physical adsorption and the formation of a slow-release structure. At the same time, the release of trace element zinc also shows a stable trend, synergistic with the nitrogen release, meeting the needs of different growth stages of plants.

[0086] In terms of the stability of vitamin B12, cyclodextrin in the fertilizer uses its special structure to encapsulate vitamin B12, forming a "molecular capsule", effectively isolating its contact with microorganisms and oxidizing substances in the soil, preventing degradation reactions from occurring, and ensuring that vitamin B12 can stably exist in the soil and precisely act on plant roots.

[0087] In terms of the preparation process, this technology simplifies the raw material pretreatment link, realizes the one-time synthesis of nitrogen slow-release materials, and reduces the cumbersome steps in the traditional process. At the same time, the mixing granulation and post-treatment processes are also optimized to ensure the uniform distribution of each component, avoid agglomeration, and improve the quality consistency of the fertilizer. Through vacuum drying and screening with a vibrating screen, the water content and size of the particles are precisely controlled, reducing the waste rate.

[0088] In terms of cost control, although new materials such as 3D-MXene and MOFs are introduced, through reasonable ratio design, their key functions are exerted while avoiding a sharp increase in costs. At the same time, natural and relatively inexpensive raw materials such as coconut shells and humic acid are used to optimize the raw material cost structure. In addition, the simplification of the preparation process also brings significant cost benefits, reducing equipment idle time, labor hours, material waste, energy consumption, and equipment maintenance costs, making this fertilizer more cost-competitive in the market.

[0089] Thus, the problems of poor stability, complex preparation process, and high cost of fertilizers containing vitamin B12 in the related art are solved.

[0090] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A fertilizer containing vitamin B12, characterized in that: The fertilizer is composed of the following weight proportions: Modified urea: 20-40 parts; Coconut shell: 1-20 parts; Hydrogel: 1-20 parts; Humic acid: 8-18 parts; Cyclodextrin: 2-10 parts; Chelating agent: 1-8 parts; Trace elements: 1-6 parts; Microbial agent: 5-15 parts; Vitamin B12: 0.01-0.3 parts.

2. A fertilizer containing vitamin B12 according to claim 1, characterized in that: The fertilizer is composed of the following weight proportions: Modified urea: 25-35 parts; Coconut shell: 10-18 parts; Hydrogel: 8-15 parts; Humic acid: 10-16 parts; Cyclodextrin: 4-8 parts; Chelating agent: 3-6 parts; Trace elements: 2-5 parts; Microbial agent: 5-10 parts; Vitamin B12: 0.05-0.2 parts.

3. A fertilizer containing vitamin B12 according to claim 1, characterized in that: The modified urea is prepared in the following weight proportions: composition: Urea: 70-90 parts; 3D-MXene: 5-15 parts; MOFs: 3-10 parts.

4. A fertilizer containing vitamin B12 according to claim 3, characterized in that: The 3D-MXene has a sheet thickness of 1-5 nm and a specific surface area of ​​not less than 200 m² / g.

5. A fertilizer containing vitamin B12 according to claim 3, characterized in that: The MOFs are metal organic framework materials based on zinc, iron or copper, and the pore size thereof is 0.5-2 nm.

6. A fertilizer containing vitamin B12 according to claim 1, characterized in that: The microbial agent comprises nitrogen-fixing bacteria, phosphate-solubilizing bacteria and potassium-solubilizing bacteria, wherein the effective viable count of the nitrogen-fixing bacteria is not less than 1×10 8 CFU / g, the effective viable count of the phosphate-solubilizing bacteria is not less than 5×10 7 CFU / g, the effective viable count of potassium-dissolving bacteria is not less than 8×10 7 CFU / g.

7. The fertilizer containing vitamin B12 according to claim 1, characterized in that: The hydrogel is a mixture of N-isopropylacrylamide, N-isopropylacrylamide and nano zinc oxide.

8. The fertilizer containing vitamin B12 according to claim 1, characterized in that: The trace elements include iron, zinc, manganese, boron and copper, and the weight ratio of each trace element is 2-5:1-3:1-2:0.5-1.5:0.1-0.

5.

9. The fertilizer containing vitamin B12 according to claim 1, characterized in that: The chelating agent is a mixture of disodium ethylenediaminetetraacetic acid and an amino acid chelating agent in a weight ratio of 1:1-3:1, and the cyclodextrin is a composite cyclodextrin composed of β-cyclodextrin and hydroxypropyl-β-cyclodextrin in a weight ratio of 2:1-5:

1.

10. A method for preparing a fertilizer containing vitamin B12 as claimed in any one of claims 1 to 9, characterized in that: The preparation method comprises: Raw material pretreatment: Pretreatment includes preparation of modified urea premix, carbonization of coconut shell, preparation of hydrogel, grinding and screening of humic acid, preparation of chelating agent, complex cyclodextrin and trace element solution, and activation of microbial agent into suspension; Mixing granulation: first add the modified urea premix to the mixer and stir, then add the pretreated raw materials, then add the microbial agent suspension and vitamin B12 and stir, and then send the materials into the granulator to form 2-5 mm particles; Post-processing: vacuum drying is used to reduce the moisture content of the particles to 5%-8%, and a vibration screen is used to screen out qualified particles of 2-5 mm.

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