CN112250506A - Green and efficient multi-element slow-release fertilizer and preparation method thereof - Google Patents
Green and efficient multi-element slow-release fertilizer and preparation method thereof Download PDFInfo
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- CN112250506A CN112250506A CN202011198814.2A CN202011198814A CN112250506A CN 112250506 A CN112250506 A CN 112250506A CN 202011198814 A CN202011198814 A CN 202011198814A CN 112250506 A CN112250506 A CN 112250506A
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05B—PHOSPHATIC FERTILISERS
- C05B7/00—Fertilisers based essentially on alkali or ammonium orthophosphates
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
- C05G3/40—Mixtures of one or more fertilisers with additives not having a specially fertilising activity for affecting fertiliser dosage or release rate; for affecting solubility
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G5/00—Fertilisers characterised by their form
- C05G5/30—Layered or coated, e.g. dust-preventing coatings
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Abstract
The invention relates to a green and efficient multi-element slow-release fertilizer and a preparation method thereof, belonging to the technical field of fertilizers. The invention adopts hydroxyapatite nanotubes to replace the traditional hydroxyapatite porous material as a base fertilizer carrier for the first time, adopts EDTA-2K as a chelating agent and nitrogen and potassium fertilizers to chelate a plurality of metal trace fertilizer elements as the base fertilizer, loads the base fertilizer in the cavity of the hydroxyapatite nanotubes, and carries out coating encapsulation by sodium alginate, thereby overcoming the defects of low fertilizer loading rate and weak slow release property of the traditional hydroxyapatite porous material, and being the multielement slow release fertilizer integrating major elements and trace elements. The invention has the advantages of simple preparation process, low raw material cost, good biocompatibility and good application prospect.
Description
Technical Field
The invention relates to a green and efficient multi-element slow-release fertilizer and a preparation method thereof, belonging to the technical field of fertilizers.
Background
Slow Release fertilizers (Slow Release Fertilizer) are a general term for fertilizers which utilize physical and chemical means to delay the Release rate of Fertilizer nutrients in soil and make the nutrients slowly released according to the nutrient requirements of each stage in the plant growth process.
Hydroxyapatite, also known as hydroxyapatite (HA or HAP for short), of the formula Ca10(PO4)6(OH)2It is the main inorganic component of human and animal bones. The artificially synthesized HAP has good biocompatibility and affinityThe biological active material has the characteristics of good biological activity, high biodegradability, wide application in the field of oral health care, bone tissue substitute materials, plastic and cosmetic surgical materials, drug carriers and the like, and is a biological active material which is nontoxic, carcinogenic-free and free of side effects. The hydroxyapatite can be used as a fertilizer slow release carrier by utilizing the characteristics of porosity, biodegradability, low cost and the like of the hydroxyapatite, and the hydroxyapatite can be used as a nutrient to be absorbed and utilized by plants after being degraded due to the fact that the hydroxyapatite contains a large amount of calcium and phosphorus, so that the hydroxyapatite is a green and efficient multifunctional slow release material. The traditional hydroxyapatite slow release fertilizer is loaded with a fertilizer substrate by an impregnation adsorption method and an in-situ method, and a base fertilizer is adsorbed in a porous structure of the hydroxyapatite.
The plants need to absorb various nutrients for growth and development. The agricultural science and technology field refers to essential nutrient elements with the content of 0.2-200 mg/kg in plants as trace elements, and the essential trace elements comprise 7 kinds of zinc, boron, manganese, molybdenum, copper, iron, chlorine and the like. Since the application amount of the nitrogen-phosphorus-potassium fertilizer is increased rapidly in more than 100 years, medium and trace element nutrients taken away by crops are not effectively supplied, the crops and soil which are lack of medium and trace elements are more and more extensive at present, and the problem is more and more serious. Therefore, the development of a fertilizer with high slow release efficiency, which integrates major elements and trace elements, is the development direction of modern agriculture.
In order to solve the technical problems, the invention develops a green and efficient multielement slow-release fertilizer and a preparation method thereof, firstly adopts hydroxyapatite nanotubes to replace the traditional hydroxyapatite porous material as a base fertilizer carrier, loads the base fertilizer in the cavities of the hydroxyapatite nanotubes, and overcomes the defects of low fertilizer loading rate and low slow-release property of the traditional hydroxyapatite porous material. Meanwhile, EDTA-2K is used as a chelating agent and nitrogen and potassium fertilizers to chelate various metal trace fertilizer elements as base fertilizers, so that the base fertilizer integrates major elements and trace elements, and has the advantages of wide application range, long fertilizer efficiency period and good application prospect.
Disclosure of Invention
The invention aims to provide a green high-efficiency multi-element slow-release fertilizer, which takes ethylene diamine tetraacetic acid dipotassium (EDTA-2K) as a chelating agent, nitrogen and potassium fertilizers, chelates a plurality of metal trace fertilizer elements as base fertilizers, takes hydroxyapatite nanotubes as base fertilizer carriers, fills the base fertilizers in cavities of the hydroxyapatite nanotubes, takes sodium alginate as an embedding agent, and encapsulates the hydroxyapatite nanotubes.
Furthermore, the metal micro-element fertilizer is more than two of zinc, manganese, molybdenum, copper and iron.
Furthermore, the hydroxyapatite nanotube is of a tubular structure with openings at two ends, the inner diameter is 10-50nm, and the outer diameter is 20-80 nm.
The invention also aims to provide a preparation method of the green and efficient multielement slow-release fertilizer, which specifically comprises the following preparation steps:
(1) dissolving ethylene diamine tetraacetic acid dipotassium (EDTA-2K) in water to prepare a solution of 0.1-0.3mol/L, adding water-soluble salts of various metal trace fertilizer elements, and uniformly stirring to form a chelated fertilizer solution;
(2) putting a hydroxyapatite nanotube serving as a base fertilizer carrier into a sealed container, vacuumizing the sealed container, inputting the chelate fertilizer solution obtained in the step (1) into the sealed container for isovolumetric impregnation, standing to enable the chelate fertilizer to be fully adsorbed in a cavity of the hydroxyapatite nanotube, aerating the sealed container after adsorption balance, standing and maintaining for 2-8h, repeating the step for 3-4 times until sufficient base fertilizer is loaded in the hydroxyapatite nanotube, and drying to obtain the hydroxyapatite nanotube loaded with the base fertilizer;
(3) preparing 1-3wt% of sodium alginate solution, uniformly stirring to form aqueous solution with certain viscosity, dispersing the hydroxyapatite nanotube loaded with the base fertilizer prepared in the step (2) in the sodium alginate solution, fully and uniformly stirring, dripping the hydroxyapatite nanotube into 1-2wt% of calcium salt solution, stirring, performing cross-linking film formation, filtering, washing and drying the obtained product to obtain the green and efficient multielement slow-release fertilizer.
Further, the water-soluble salt of the metal microelement fertilizer element is more than two of nitrate, acetate or chloride of zinc, manganese, molybdenum, copper and iron.
Further, the preparation method of the hydroxyapatite nanotube comprises the following steps:
adding organic amine as a template agent into an aqueous solution containing dihydric phosphate and a calcium salt, mixing and stirring uniformly, wherein the molar ratio of the dihydric phosphate to the calcium salt to the template agent is 1:1-5:2-8, transferring the mixed solution into a stainless steel reaction kettle with a polytetrafluoroethylene lining, and carrying out hydrothermal reaction at 100-200 ℃ for 2-24h to obtain the catalyst.
Further, the organic amine is one or more of ethylenediamine, n-butylamine, hexylamine, hexamethylenediamine and dodecylamine.
Further, the hydrothermal reaction is preferably carried out at 120-150 ℃ for 4-10 h.
According to the invention, the traditional hydroxyapatite porous material is replaced by the hydroxyapatite nanotube as the base fertilizer carrier for the first time, and the base fertilizer is loaded in the cavity of the hydroxyapatite nanotube by a negative pressure isometric impregnation method and combining the siphon effect of the nanotube, so that the defects of low fertilizer loading rate and low slow release property of the traditional hydroxyapatite porous material are overcome. Meanwhile, the hydroxyapatite has strong biodegradability, and a large amount of phosphorus and calcium contained in the hydroxyapatite can be absorbed as plant nutrients after degradation, so that zero residue is realized. Namely, the hydroxyapatite nanotube has double functions, not only exists as an efficient slow release carrier, but also provides calcium and phosphate fertilizers required by plants, has low cost, is green and environment-friendly, and is the innovation point of the invention.
The invention takes ethylene diamine tetraacetic acid dipotassium (EDTA-2K) as a chelating agent and nitrogen and potassium fertilizers, chelates a plurality of metal trace fertilizer elements as base fertilizers, combines calcium and phosphate fertilizers in hydroxyapatite, can provide most nutrient elements required by plant growth, is a multi-element slow release fertilizer integrating major elements and trace elements, and has wide application range, rich nutrition and long fertilizer efficiency period.
The hydroxyapatite nanotube loaded with the base fertilizer can further enhance the slow release performance after being encapsulated by marine organism polysaccharide sodium alginate. The invention has the advantages of simple preparation process, low raw material cost, good biocompatibility and good application prospect.
Drawings
Fig. 1 is a Transmission Electron Microscope (TEM) image of the hydroxyapatite nanotube prepared by the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Preparation of hydroxyapatite nanotubes
Adding a template agent hexylamine into an aqueous solution containing sodium dihydrogen phosphate and calcium chloride, uniformly mixing and stirring, wherein the molar ratio of the sodium dihydrogen phosphate to the calcium chloride to the hexylamine is 1:2:5, transferring the mixed solution into a stainless steel reaction kettle with a polytetrafluoroethylene lining, and carrying out hydrothermal reaction at 140 ℃ for 8 hours to obtain a hydroxyapatite nanotube (HA-NT); FIG. 1 is a Transmission Electron Micrograph (TEM) of HA-NT, and it is clear from FIG. 1 that HA-NT is a nanotube-like structure with two open ends, an inner diameter of about 10-50nm and an outer diameter of about 20-80 nm.
Example 2
(1) Dissolving EDTA-2K in water to prepare a 0.2mol/L solution, adding nitrates of zinc, manganese and iron, and uniformly stirring to form a chelate fertilizer solution;
(2) filling the HA-NT prepared in the example 1 as a base fertilizer carrier into a sealed container, vacuumizing, inputting the chelated fertilizer solution obtained in the step (1) into the sealed container for isovolumetric impregnation, standing, aerating the sealed container after adsorption balance, standing and maintaining for 6 hours, repeating the step for 3 times, and drying to obtain the base fertilizer-loaded HA-NT;
(3) preparing a 2wt% sodium alginate solution, uniformly stirring, dispersing the HA-NT loaded with the base fertilizer prepared in the step (2) in the sodium alginate solution, sufficiently and uniformly stirring, dripping the HA-NT into a 1wt% calcium chloride solution, stirring, crosslinking to form a film, filtering, washing and drying to obtain the multielement slow release fertilizer, which is marked as F-2.
Example 3
(1) Dissolving EDTA-2K in water to prepare a 0.3mol/L solution, adding nitrates of molybdenum, copper and iron, and uniformly stirring to form a chelate fertilizer solution;
(2) filling the HA-NT prepared in the example 1 as a base fertilizer carrier into a sealed container, vacuumizing, inputting the chelated fertilizer solution obtained in the step (1) into the sealed container for isovolumetric impregnation, standing, aerating the sealed container after adsorption balance, standing and maintaining for 4 hours, repeating the step for 4 times, and drying to obtain the base fertilizer-loaded HA-NT;
(3) preparing 1wt% sodium alginate solution, uniformly stirring, dispersing the HA-NT loaded with the base fertilizer prepared in the step (2) in the sodium alginate solution, fully and uniformly stirring, dripping the HA-NT into 1wt% calcium chloride solution, stirring, crosslinking to form a film, filtering, washing and drying to obtain the multielement slow release fertilizer, which is marked as F-3.
Example 4
The slow release fertilizers obtained in examples 2 to 3 were subjected to in-soil slow release performance tests.
100g of air-dried and sieved soil is weighed and injected into a separation column and is fully wetted by deionized water. Weighing 2g of slow release fertilizer, adding the slow release fertilizer to the surface of the separation column, covering 20g of soil, and continuously fully wetting with deionized water. The nutrient release rate was measured by passing 150ml of deionized water through the column after the incubation at room temperature for various periods of time, and collecting the filtrate, and the results are also shown in Table 1.
TABLE 1 Release Rate (in%)
As can be seen from the table 1, the multielement slow-release fertilizer prepared by the invention has the slow-release effect of various nutrient elements, wherein the release rate of nitrogen and potassium fertilizers at 105d is 81.3-87.1%, the release rate of phosphate fertilizers at 105d is about 42%, the fertilizer effect is long, the balanced supply of various nutrients of plants can be realized, and the multielement slow-release fertilizer has a potential application prospect.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (8)
1. A green and efficient multielement slow-release fertilizer is characterized in that ethylene diamine tetraacetic acid dipotassium (EDTA-2K) is used as a chelating agent, a nitrogen fertilizer and a potassium fertilizer, a plurality of metal trace fertilizer elements are chelated as a base fertilizer, hydroxyapatite nanotubes are used as a base fertilizer carrier, the base fertilizer is filled in cavities of the hydroxyapatite nanotubes, sodium alginate is used as an embedding agent, and the hydroxyapatite nanotubes are encapsulated by a coating.
2. The green high-efficiency multielement slow-release fertilizer as claimed in claim 1, wherein the metal microelement fertilizer is more than two of zinc, manganese, molybdenum, copper and iron.
3. The green high-efficiency multielement slow-release fertilizer according to any one of claims 1-2, characterized in that the hydroxyapatite nanotube has a tubular structure with openings at two ends, the inner diameter is 10-50nm, and the outer diameter is 20-80 nm.
4. The method for preparing green high-efficiency multielement slow-release fertilizer according to claim 1, characterized by comprising the following preparation steps:
(1) dissolving ethylene diamine tetraacetic acid dipotassium (EDTA-2K) in water to prepare a solution of 0.1-0.3mol/L, adding water-soluble salts of various metal trace fertilizer elements, and uniformly stirring to form a chelated fertilizer solution;
(2) putting a hydroxyapatite nanotube serving as a base fertilizer carrier into a sealed container, vacuumizing the sealed container, inputting the chelate fertilizer solution obtained in the step (1) into the sealed container for isovolumetric impregnation, standing to enable the chelate fertilizer to be fully adsorbed in a cavity of the hydroxyapatite nanotube, aerating the sealed container after adsorption balance, standing and maintaining for 2-8h, repeating the step for 3-4 times until sufficient base fertilizer is loaded in the hydroxyapatite nanotube, and drying to obtain the hydroxyapatite nanotube loaded with the base fertilizer;
(3) preparing 1-3wt% of sodium alginate solution, uniformly stirring to form a water solution with certain viscosity, dispersing the hydroxyapatite nanotube loaded with the base fertilizer prepared in the step (2) in the sodium alginate solution, fully and uniformly stirring, dripping the hydroxyapatite nanotube into 1-2wt% of calcium salt solution, stirring, performing cross-linking film formation, filtering, washing and drying the obtained product to obtain the green and efficient multielement slow-release fertilizer.
5. The method according to claim 4, wherein the water-soluble salt of the metal trace element is two or more of nitrate, acetate or chloride of zinc, manganese, molybdenum, copper or iron.
6. The method according to claim 4, wherein the hydroxyapatite nanotubes are prepared by the following steps:
adding organic amine as a template agent into an aqueous solution containing dihydric phosphate and a calcium salt, mixing and stirring uniformly, wherein the molar ratio of the dihydric phosphate to the calcium salt to the template agent is 1:1-5:2-8, transferring the mixed solution into a stainless steel reaction kettle with a polytetrafluoroethylene lining, and carrying out hydrothermal reaction at 100-200 ℃ for 2-24h to obtain the catalyst.
7. The method according to claim 6, wherein the organic amine is one or more of ethylenediamine, n-butylamine, hexylamine, hexyldiamine, and dodecylamine.
8. The preparation method according to claim 6, wherein the hydrothermal reaction is preferably carried out at 120-150 ℃ for 4-10 h.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101589709A (en) * | 2009-07-03 | 2009-12-02 | 吉林大学 | Adsorption method for preparing hydroxyapatite pesticide, slow-release fertilizer compound |
| CN101773112A (en) * | 2010-01-28 | 2010-07-14 | 武汉理工大学 | Preparation method of pesticide diuron slow controlled release nanometer composite material |
| CN101786615A (en) * | 2010-03-12 | 2010-07-28 | 南京大学 | Hydroxyapatite nanotube and preparation and application thereof in bone repair |
| CN109529047A (en) * | 2018-12-14 | 2019-03-29 | 信阳师范学院 | A kind of compound silver nanometer hydroxyapatite/alginate microsphere and preparation method thereof |
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- 2020-10-31 CN CN202011198814.2A patent/CN112250506A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101589709A (en) * | 2009-07-03 | 2009-12-02 | 吉林大学 | Adsorption method for preparing hydroxyapatite pesticide, slow-release fertilizer compound |
| CN101773112A (en) * | 2010-01-28 | 2010-07-14 | 武汉理工大学 | Preparation method of pesticide diuron slow controlled release nanometer composite material |
| CN101786615A (en) * | 2010-03-12 | 2010-07-28 | 南京大学 | Hydroxyapatite nanotube and preparation and application thereof in bone repair |
| CN109529047A (en) * | 2018-12-14 | 2019-03-29 | 信阳师范学院 | A kind of compound silver nanometer hydroxyapatite/alginate microsphere and preparation method thereof |
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