A water-soluble primary silicic acid-containing medium / microelement compound fertilizer and a preparation method thereof

Abstract

The present application belongs to the technical field of agricultural fertilizer, and particularly relates to a medium / trace element compound fertilizer containing water-soluble orthosilicic acid and a preparation method thereof. The compound fertilizer comprises the following components in parts by weight: 10-110 parts of water-soluble orthosilicic acid, 10-90 parts of soluble calcium salt, 5-20 parts of soluble magnesium salt, 0.5-5 parts of soluble iron salt, 0.5-10 parts of soluble manganese salt, 0.5-10 parts of soluble zinc salt, and 1-10 parts of potassium dihydrogen phosphate. The compound fertilizer can help improve photosynthesis of crops, increase mechanical strength of stems and stalks of crops, enhance air permeability in crops, prevent root decay and early decline, enhance drought resistance, pest resistance, cold resistance, salt resistance, dry hot wind resistance and other stress resistance of crops, and improve utilization rate of nitrogen, phosphorus, potassium and boron fertilizers, thereby greatly improving yield of crops.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of agricultural fertilizer, and particularly relates to a medium / trace element compound fertilizer containing water-soluble orthosilicic acid and a preparation method thereof. BACKGROUND

[0002] Silicon fertilizer has a long history of application in agriculture. In 1928, American researchers found that silicon can increase the yield of crops such as rice. In 1955, Japan listed silicon fertilizer as a new type of fertilizer in the Fertilizer Law and began to produce and sell silicon fertilizer. After Japan, Korea, the Philippines, India and other Asian countries introduced and promoted silicon fertilizer. With the in-depth study of silicon fertilizer, the scope of silicon fertilizer research has gradually expanded, and the coverage of silicon fertilizer research has become more and more extensive. From the promotion of crop stem and leaf growth by silicon fertilizer, the inhibition of soil compaction and acidification, to the passivation of heavy metals by silicon fertilizer, and the sustainable development of agriculture, the research on silicon fertilizer has emerged new dynamics and new fields.

[0003] In China, silicon fertilizer originated in the 1990s. Fly ash, ore slag and the like were filled into the land as solid silicon fertilizer. However, the land absorbs little solid non-flowing silicon, for example, patent 95111357.7, a formula and production method of silicon calcium magnesium phosphorus fertilizer, wherein the formula of the silicon calcium magnesium phosphorus fertilizer disclosed is 38%-48% low-grade phosphate rock, 12%-16% lime, 15-25% lime material, and 20-25% silicon sand. These components are not easy to water, and their effects are not obvious. In the later period, water-soluble sodium silicate and potassium silicate are used as flush silicon fertilizer. Although this kind of silicon fertilizer can be dissolved, it has strong alkalinity and can easily cause soil alkalization, which has certain destructive effect on the soil.

[0004] At present, the focus of silicon fertilizer research is how to produce a water-soluble silicon fertilizer without strong alkalinity. Therefore, the development of a compound fertilizer containing water-soluble acidic orthosilicic acid will play an important role in promoting the comprehensive and rapid absorption of nutrients by crops and promoting agricultural development. SUMMARY

[0005] The medium / trace element compound fertilizer containing water-soluble orthosilicic acid prepared by the present application mainly solves the technical problem that traditional silicon fertilizer has high alkalinity and cannot be matched with calcium, magnesium, phosphorus, potassium, nitrogen, iron, zinc and other nutrient components. Traditional silicon fertilizer will directly promote calcium, magnesium, iron and other nutrient components to become hydroxide precipitates, which cannot be well absorbed by crops.

[0006] To solve the problems in the prior art, the application provides a medium / trace element compound fertilizer containing water-soluble orthosilicic acid and a preparation method thereof.

[0007] To achieve the above object, the application adopts the following technical scheme:

[0008] One of the objects of the application is to disclose a medium / trace element compound fertilizer containing water-soluble orthosilicic acid, which comprises the following components in parts by weight: 10-110 parts of water-soluble orthosilicic acid, 10-90 parts of soluble calcium salt, 5-20 parts of soluble magnesium salt, 0.5-5 parts of soluble iron salt, 0.5-10 parts of soluble manganese salt, 0.5-10 parts of soluble zinc salt, and 1-10 parts of potassium dihydrogen phosphate. Appropriate amount of water can be added to adjust the nutrient component ratio of the silicon fertilizer.

[0009] The water-soluble orthosilicic acid is spherical silicon dioxide particles with a particle size of 5-150 nm, a pH of 2-7, and a silicon content of 168-278 g / L.

[0010] The soluble salt comprises one or a combination of nitrate salt, chloride salt or organic acid salt.

[0011] Preferably, the water-soluble orthosilicic acid is prepared by the following method:

[0012] (1) Preparation of active orthosilicic acid: sodium silicate solution is passed through a weakly acidic cation exchange resin to prepare weakly acidic orthosilicic acid with a pH of 4-6; then acid is added dropwise for reaction, the pH is adjusted to 2-3, and then heated to prepare active orthosilicic acid;

[0013] (2) Preparation of seed liquid: the active orthosilicic acid obtained in step 1 is mixed with lye and then heated to prepare a seed liquid;

[0014] (3) Preparation of low-concentration stable orthosilicic acid: a dispersing agent is added to the seed liquid obtained in step 2, and an organic polymer monomer is added dropwise to make the active orthosilicic acid continue to polymerize, and then citric acid is added to adjust the pH to 2-7 to prepare low-concentration stable orthosilicic acid;

[0015] (4) Preparation of high-concentration stable orthosilicic acid: the low-concentration stable orthosilicic acid prepared in step 3 is concentrated by a membrane to prepare high-concentration stable water-soluble orthosilicic acid.

[0016] Preferably, the sodium silicate solution in step 1 has a mass fraction of 3%-20%; the acid is a water-soluble organic acid, including citric acid, oxalic acid, acetic acid, malic acid, and one or more combinations of acidic amino acids; and the solution is heated to 30-60°C.

[0017] Preferably, in step 2, the mass ratio of active orthosilicic acid to alkaline solution is 100-300:0.5-5; the alkaline solution is one or more of inorganic or organic alkalis; the inorganic alkali includes one or more of lithium hydroxide, sodium hydroxide, potassium hydroxide, and ammonia water; the organic alkali includes one or more of methylamine, ethylamine, ethylenediamine, and propylamine; and the solution is heated to 50-100°C.

[0018] Preferably, in step 3, the pH of the seed solution is adjusted to 8-10, and a dispersant is added; the dispersant is a nitrogen-containing water-soluble polymer, preferably polyvinylpyrrolidone.

[0019] Preferably, the organic polymerizing monomer in step 3 is one or more of the following: hydroxyl or methoxyl, amino or graft copolymerizing monomers, including hydroxysilane, α,w-hydroxymethoxyhexamethyltrisiloxane, and not limited to other organosilanes; the mass ratio of the active orthosilicic acid to α,w-hydroxymethoxyhexamethyltrisiloxane is 0.1-3:500-1500:0.1-10.

[0020] Preferably, the polymerization reaction temperature is controlled at 60-100℃ and the polymerization reaction time is more than 8 hours; the ratio of the weakly acidic orthosilicic acid to citric acid is 10-90:0.1-2.

[0021] The second objective of this invention is to disclose a method for preparing the above-mentioned medium / micronutrient compound fertilizer containing water-soluble orthosilicic acid, comprising the following steps: first, adding a certain amount of water to water-soluble orthosilicic acid to adjust the silicon content to 120 g / L; then, while stirring, adding soluble calcium salt, soluble magnesium salt, soluble iron salt, soluble manganese salt, soluble zinc salt, and potassium dihydrogen phosphate, and stirring evenly to obtain the medium / micronutrient compound fertilizer containing water-soluble orthosilicic acid.

[0022] Beneficial effects

[0023] This invention discloses a compound fertilizer containing water-soluble orthosilicic acid, which can help improve crop photosynthesis, increase the mechanical strength of crop stems, enhance the aeration of the crop, prevent root rot and premature aging, enhance the crop's resistance to drought, pests, cold, salt, and hot dry winds, and improve the utilization rate of nitrogen, phosphorus, potassium, and boron fertilizers, thereby greatly increasing crop yield.

[0024] The application also self-prepares a water-soluble orthosilicic acid, which is spherical silicon dioxide particles with a particle size of 5-150 nm, a pH of 2-7, and a silicon content of up to 278 g / L. The use of this orthosilicic acid in combination with calcium, magnesium, phosphorus, potassium, nitrogen, iron, zinc and other nutrients can make crops grow balancedly and rapidly. Moreover, the preparation process of the water-soluble orthosilicic acid is simple, reduces the high-temperature alkalization reaction, and obtains high-purity orthosilicic acid, which is green and environmentally friendly. Moreover, the orthosilicic acid has good dispersibility and can stably exist for more than 2 years. DETAILED DESCRIPTION

[0025] Hereinafter, the present application will be described in detail. Before proceeding with the description, it should be understood that the terms used in the specification and the appended claims should not be construed as limiting to the general and dictionary meanings and should be construed in the context of what the inventor could reasonably be intending to mean, as reflected in the patent specification. Accordingly, the description presented here is merely for illustrative purposes and is not intended to limit the scope of the application, and it should be understood that other equivalents or modifications are possible from the spirit and scope of the application.

[0026] The following examples are merely set forth as examples of embodiments of the application and are not to be construed as limiting the application in any way, as those skilled in the art will be able to devise alternative ways of practicing the application without departing from the spirit and scope of the application. Unless otherwise indicated, the reagents and instruments used in the following examples are commercially available products.

[0027] Example 1

[0028] A preparation method of a medium / microelement compound fertilizer containing water-soluble orthosilicic acid is as follows:

[0029] (1) A 3% sodium silicate solution was used to prepare weakly acidic orthosilicic acid with a pH of 4 through a weakly acidic cation exchange resin. Citric acid was added dropwise to adjust the pH to 3, and the mixture was heated to 50°C to prepare active orthosilicic acid. The active orthosilicic acid was mixed with alkaline ammonia solution and heated to 60°C to prepare a seed solution. The mass ratio of active orthosilicic acid to ammonia solution was 100:1.0. Polyvinylpyrrolidone (PVP) was added to the seed solution, and active orthosilicic acid was added dropwise to continue polymerization. Hydroxysilane and α,w-hydroxymethoxyhexamethyltrisiloxane (not limited to other silane coupling agents) were added dropwise. The mass ratio of active orthosilicic acid to α,w-hydroxymethoxyhexamethyltrisiloxane was 0.1:500:0.1. The pH was adjusted to 9.5, and the reaction temperature was controlled at 70°C. The polymerization reaction was carried out for more than 8 hours. Citric acid was added, and the ratio of weakly acidic orthosilicic acid to citric acid was 10-90:0.1-2 to adjust the pH to 7. This prepared low-concentration, stable orthosilicic acid. The prepared orthosilicic acid had a particle size of 8 nanometers, a pH of 7, and a silicon content of 168 g / L.

[0030] (2) Orthosilicic acid aqueous solution (FAS-30H1, silicon content 168g / L, pH: 4.8), diluted with water to 10g / L, add calcium formate 90g / L, magnesium nitrate 10g / L, ferric chloride 5g / L, manganese nitrate 0.5g / L, zinc gluconate 5g / L, and potassium dihydrogen phosphate 1g / L to prepare an acidic orthosilicic acid compound fertilizer with pH 3.5. After diluting 300 times, the pH is 4.0.

[0031] Field trials were conducted in rice paddies at the Yellow River Estuary in Dongying in September-October 2023, involving both aerial spraying and drip irrigation.

[0032] Location: Huanghekou Town Village, Kenli District, Dongying City; Soil type: Sandy alkaline soil; Parent material: Marine parent material; Texture: Sandy loam, slightly alkaline, prone to nutrient loss; Topsoil thickness: 25 cm; Previous crop: Rice; Average annual yield per mu: 1150 kg; Irrigation and drainage conditions: Ditches; Average annual fertilization level: 150 catties of compound fertilizer.

[0033] Experimental method: The medium / micro element compound fertilizer containing water-soluble orthosilicic acid prepared in this example was applied by aerial spraying at a rate of 30-50 ml / mu once each during the tillering stage, jointing stage, and one week before heading of rice.

[0034] The soil test results before and after the experiment are compared in Table 1 below:

[0035] Table 1. Soil test results before and after the experiment

[0036]

[0037] Treatment 1: The farm purchased 100 catties / mu of 17*3 chlorine-containing compound fertilizer and sprayed 3 times a mu of liquid orthosilicic acid FAS-30H1 (50 ml each time).

[0038] Treatment 2: Farm self-purchase 17*3 chlorine-containing compound fertilizer 100 kg / mu + urea.

[0039] The growth period is recorded, and the experimental results are shown in Table 2.

[0040] Table 2. Experimental results of treatment 1 and treatment 2

[0041]

[0042] Table 3. Plant agronomic trait observation table

[0043]

[0044]

[0045] Example 2

[0046] A preparation method of a medium element / microelement compound fertilizer containing water-soluble orthosilicic acid is as follows:

[0047] (1) 2% sodium silicate solution, pass through weakly acidic cation exchange resin to prepare weakly acidic orthosilicic acid with pH 4, add citric acid dropwise for reaction, adjust pH to 3, heat to 60°C to prepare active orthosilicic acid. Mix the active silicic acid with sodium hydroxide and heat to 70°C to prepare a seed solution. Add a dispersant polyimide to the seed solution, continue to dropwise add active orthosilicic acid for continuous polymerization, and dropwise add hydroxyl silane α, w-hydroxymethoxyhexamethyltrisiloxane at the same time. The mass ratio of polyimide: active silicic acid to α, w-hydroxymethoxyhexamethyltrisiloxane is 0.1:500:0.6. Adjust the pH to 9.5 and control the reaction temperature at 90°C. The reaction polymerization is carried out for more than 8 hours. Add citric acid. The ratio of weakly acidic orthosilicic acid to citric acid is 90:1, and the pH is adjusted to 6.5. A low-concentration stable orthosilicic acid is prepared. The prepared orthosilicic acid has a particle size of 10-20 nanometers, a pH of 6.5, and a silicon content of 168 g / L.

[0048] (2) Orthosilicic acid aqueous solution (FAS-30H2, silicon content 168 g / L, pH: 5-7), dilute with water to 110 g / L, add calcium formate 50 g / L, add magnesium nitrate 10 g / L, add iron nitrate 5 g / L, add manganese nitrate 0.5 g / L, add zinc gluconate 10 g / L, add potassium dihydrogen phosphate 5 g / L, and prepare a compound fertilizer with pH 5.4. After dilution by 300 times, the pH is 5.8.

[0049] The field test was carried out in Dongying Yellow River estuary rice field from September to October 2023.

[0050] Location: Huanghekou town, Kenli district, Dongying city; Soil name: saline-alkali soil; Soil parent material: marine parent material; Soil texture: sandy loam, partial alkali, and leaching; Plough layer thickness: 25 cm; Previous crop: rice; Annual yield per mu: 1150; Irrigation condition: ditch; Annual fertilization level: 150 kg of compound fertilizer.

[0051] Test method: The medium and trace element compound fertilizer containing water-soluble orthosilicic acid prepared in this example was each sprayed once at the tillering stage, the jointing stage, and one week before the heading stage of rice. The comparison of soil test results before and after the test is shown in Table 4 below:

[0052] Table 4. Soil test results before and after the test

[0053]

[0054]

[0055] Treatment 2: 100 kg / mu of 17*3 chlorine-containing compound fertilizer purchased by the farm, and urea.

[0056] Treatment 1: 100 kg / mu of 17*3 chlorine-containing compound fertilizer purchased by the farm + spraying 3 times of 50 ml of medium-mu liquid orthosilicic acid FAS-30H2 each time.

[0057] Growth period record.

[0058] Table 5. Experimental results of treatment 1 and treatment 2

[0059]

[0060] Table 6. Plant agronomic trait investigation table

[0061]

[0062] Example 3

[0063] A medium and trace element compound fertilizer containing water-soluble orthosilicic acid, comprising the following components by weight: 10 parts of water-soluble orthosilicic acid, 10 parts of soluble calcium salt, 5 parts of soluble magnesium salt, 0.5 parts of soluble iron salt, 0.5 parts of soluble manganese salt, 0.5 parts of soluble zinc salt, and 1 part of potassium dihydrogen phosphate; the water-soluble orthosilicic acid is spherical silicon dioxide particles with a particle size of 5 nanometers, a pH of 2, and a silicon content of 168 g / L.

[0064] Example 4

[0065] A medium trace element compound fertilizer containing water-soluble orthosilicic acid, characterized in that it comprises the following components in parts by weight: water-soluble orthosilicic acid 110 parts, soluble calcium salt 90 parts, soluble magnesium salt 20 parts, soluble iron salt 5 parts, soluble manganese salt 10 parts, soluble zinc salt 10 parts, potassium dihydrogen phosphate 10 parts; the water-soluble orthosilicic acid is spherical silicon dioxide particles with a particle size of 150 nm, a pH of 7 and a silicon content of 278 g / L.

[0066] Example 5

[0067] A medium trace element compound fertilizer containing water-soluble orthosilicic acid, comprising the following components in parts by weight: water-soluble orthosilicic acid 60 parts, soluble calcium salt 50 parts, soluble magnesium salt 10 parts, soluble iron salt 3 parts, soluble manganese salt 3 parts, soluble zinc salt 3 parts, potassium dihydrogen phosphate 5 parts; the water-soluble orthosilicic acid is spherical silicon dioxide particles with a particle size of 100 nm, a pH of 5 and a silicon content of 200 g / L.

[0068] The above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, the technical solutions recorded in the foregoing examples can still be modified by those of ordinary skill in the art, or some of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions claimed by the present application.

Claims

1. A method for preparing a water-soluble primary silicic acid-containing medium / trace element compound fertilizer, characterized by, The compound fertilizer comprises the following components in parts by weight: water-soluble orthosilicic acid 10-110 parts, soluble calcium salt 10-90 parts, soluble magnesium salt 5-20 parts, soluble iron salt 0.5-5 parts, soluble manganese salt 0.5-10 parts, soluble zinc salt 0.5-10 parts, potassium dihydrogen phosphate 1-10 parts; the water-soluble orthosilicic acid is spherical silicon dioxide particles with a particle size of 5-150 nm, a pH of 2-7 and a silicon content of 168-278 g / L; The water-soluble orthosilicic acid is prepared by the following method: S1, preparation of active orthosilicic acid: a sodium silicate solution with a mass fraction of 3%-20% is passed through a weakly acidic cation exchange resin to prepare weakly acidic orthosilicic acid with a pH of 4-6; then acid is added dropwise for reaction, the pH is adjusted to 2-3, and then heated to 30-60 DEG C to prepare active orthosilicic acid; The acid is a water-soluble organic acid, including one or a combination of citric acid, oxalic acid, acetic acid, malic acid and acidic amino acid; S2, preparation of seed liquid: the active orthosilicic acid obtained in step S1 is mixed with an alkali liquor at a mass ratio of 100-300:0.5-5, and then heated to 50-100 DEG C to prepare a seed liquid; The alkali liquor is one or a combination of inorganic alkali or organic alkali; the inorganic alkali includes one or a combination of lithium hydroxide, sodium hydroxide, potassium hydroxide and ammonia water; the organic alkali includes one or a combination of methylamine, ethylamine, ethylenediamine and propylamine; S3, preparation of low-concentration stable orthosilicic acid: the pH of the seed liquid obtained in step S2 is adjusted to 8-10, polyvinylpyrrolidone is added, and hydroxysilane, alpha,w-hydroxymethoxyl hexamethyltrisiloxane and other organosilanes are added dropwise, the mass ratio of the active orthosilicic acid to alpha,w-hydroxymethoxyl hexamethyltrisiloxane being 0.1-3:500-1500:0.1-10, the pH being adjusted to 9.5, and the reaction temperature being controlled at 60-100 DEG C; the active orthosilicic acid is allowed to continue the polymerization reaction for more than 8 hours, citric acid is added after the reaction is completed, the weakly acidic orthosilicic acid is mixed with the citric acid at a ratio of 10-90:0.1-2, the pH is adjusted to 2-7, and low-concentration stable orthosilicic acid is prepared; S4, preparation of high-concentration stable orthosilicic acid: the low-concentration stable orthosilicic acid prepared in step S3 is concentrated by a membrane to prepare high-concentration stable water-soluble orthosilicic acid; The soluble salt includes one or a combination of nitrate or chloride or organic acid salt; The preparation method comprises the following steps: a certain amount of water is added to the water-soluble orthosilicic acid to adjust the silicon content to 120 g / L, then the soluble calcium salt, the soluble magnesium salt, the soluble iron salt, the soluble manganese salt, the soluble zinc salt and the potassium dihydrogen phosphate are added under stirring, and the mixture is stirred uniformly to obtain the medium-element / microelement compound fertilizer containing water-soluble orthosilicic acid.

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