CN110819357B - Acidic soil remediation agent and preparation and application thereof - Google Patents
Acidic soil remediation agent and preparation and application thereof Download PDFInfo
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- CN110819357B CN110819357B CN201911086731.1A CN201911086731A CN110819357B CN 110819357 B CN110819357 B CN 110819357B CN 201911086731 A CN201911086731 A CN 201911086731A CN 110819357 B CN110819357 B CN 110819357B
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- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K17/00—Soil-conditioning materials or soil-stabilising materials
- C09K17/40—Soil-conditioning materials or soil-stabilising materials containing mixtures of inorganic and organic compounds
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
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- C09K2101/00—Agricultural use
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K2109/00—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE pH regulation
Abstract
The invention relates to an acidic soil remediation agent and preparation and application thereof. The soil remediation agent obtained in the invention can improve the pH of soil, inhibit the loss of basic cations in the soil, and fundamentally inhibit soil acidification, and has the characteristics of obvious effect, environmental friendliness and the like, and has wide application prospect.
Description
Technical Field
The invention belongs to the field of soil remediation agents and preparation and application thereof, and particularly relates to an acidic soil remediation agent and preparation and application thereof.
Background
More than two hundred million acres of acid soil exist in China, and the soil acidification degree is in an aggravation situation. The acidified soil is mainly distributed in the south of China, and the root cause of soil acidification is that the soil is changed into aluminum soil through base dissolution. Southern rains easily cause salt-based cations (free Ca) in the soil2+、Mg2+、K+、Na+) Leaching loss is caused, so that the adsorption sites on the surface of the soil colloid are easy to be externally input and the H secreted by the plant root system+Occupy, these H+Make Al in soil3+Released and hydrolyzed to produce H+To intensify soil acidification. The soil acidification can cause the loss of trace elements in soil, cause nutrient deficiency, influence the crop yield and quality, and become a key factor for restricting the sustainable agricultural production of China.
The existing acid soil improvement technology mainly comprises modes of applying quicklime, organic fertilizers and the like, which can inhibit soil acidification to a certain degree, but have the following defects: 1) quicklime easily causes soil hardening and destroys the ecological balance of the soil; 2) the organic fertilizer has large consumption, and consumes a large amount of manpower and material resources. These deficiencies limit their wide spread. Therefore, the research and development of a low-cost and light-weight and simplified acid soil remediation agent through scientific and technological innovation are urgently needed.
CN 110257080A discloses an acidic soil repairing agent, a preparation method and an application thereof, wherein strong acid and strong alkali are used in the preparation process of the repairing agent, so that secondary pollution is easily caused.
Disclosure of Invention
The invention aims to solve the technical problem of providing an acidic soil remediation agent and preparation and application thereof, overcoming the defect that strong acid and strong alkali are adopted to easily cause secondary pollution in the prior art, and the invention takes attapulgite and red mud as basic materials to prepare a functionalized nano material through chemical modification, can improve the pH value of soil, can inhibit the loss of basic cations in the soil, can fundamentally inhibit soil acidification, and has the characteristics of obvious effect, environmental friendliness and the like, and has wide application prospect.
The invention provides a soil remediation agent, which comprises the following raw materials in parts by weight: 300 parts of attapulgite and red mud, 5-10 parts of sodium polyacrylate, 10-20 parts of polyethyleneimine and 1000 parts of water.
The attapulgite (colloidal grade) is 100-200 meshes, and the red mud is 100-200 meshes; the mass ratio of the attapulgite to the red mud is 1-3: 3-5.
The components comprise: 2-4 parts of N-hydroxysuccinimide and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride
1-3 parts.
Further, the raw material components comprise, by weight: the adhesive comprises, by mass, 100 parts of attapulgite and red mud, 5 parts of sodium polyacrylate, 2 parts of N-hydroxysuccinimide, 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride, 10 parts of polyethyleneimine and 1000 parts of water, wherein the mass ratio of the attapulgite to the red mud is 1: 3.
further, the raw material components comprise, by weight: attapulgite, 200 parts of red mud and 7.5 parts of sodium polyacrylate
The adhesive comprises the following components, by weight, 3 parts of N-hydroxysuccinimide, 2 parts of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride, 15 parts of polyethyleneimine and 1000 parts of water; wherein the mass ratio of the attapulgite to the red mud is 2: 4.
further, the raw material components comprise, by weight: 300 parts of attapulgite and red mud, 10 parts of sodium polyacrylate, 4 parts of N-hydroxysuccinimide, 3 parts of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride and polyethyleneimine
20 parts of water and 1000 parts of water; wherein the mass ratio of the attapulgite to the red mud is 3: 5.
the invention discloses a preparation method of a soil remediation agent, which comprises the following steps:
(1) mixing attapulgite and red mud, adding into water to obtain mixed solution, adding sodium polyacrylate, and heating at room temperature
Stirring at 500rpm for 3-5h at 300-;
(2) adding N-hydroxysuccinimide and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride in the step (1), adjusting the pH to 8.5-9.5, and stirring at the normal temperature of 300rpm for 8-10 h;
(3) adding polyethyleneimine into the step (2), stirring at the normal temperature of 300 and 500rpm for 10-12h, filtering, washing, drying,
crushing to 100-mesh and 200-mesh to obtain the soil remediation agent.
The preferred mode of the above preparation method is as follows:
the mass ratio of the attapulgite to the red mud in the step (1) is 1-3: 3-5.
The concentration of the mixed solution in the step (1) is 100-300 g/L; adding 5-10 g/L sodium polyacrylate (molecular weight 800-100 ten thousand).
In the step (2), 2-4 g/L of N-hydroxysuccinimide and 1-3 g/L of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride are added into the system.
10-20 g/L of polyethyleneimine is added in the step (3), and the molecular weight of the polyethyleneimine is 1600-1800.
The water washing in the step (3) is carried out for 3-5 times by using 200-400mL of water; drying at 50-70 deg.C.
In the step (2), the pH is adjusted to be: the pH was adjusted to 8.5-9.5 with sodium carbonate and sodium bicarbonate buffer solution.
The soil remediation agent prepared by the method is provided by the invention.
The invention provides an application of the soil remediation agent.
The method specifically comprises the following steps: the repairing agent is uniformly spread on the surface of soil (pH4-6) according to 50-100 kg/mu, then rotary tillage is carried out, and after 30 days, the pH of the soil can be increased by 1-3 units and free Ca is added2+The content is increased by 800mg/kg for 400-.
Advantageous effects
The invention provides an acidic soil repairing agent, which is prepared from natural nano clay, industrial waste residue, a novel functional high polymer material and a high polymer through a chemical reaction. The repairing agent has three functions: 1) the adsorption capacity to the basic cations is improved through a large amount of carboxyl, and the leaching loss of the basic cations is reduced; 2) the pH value of the soil and the adsorption capacity to basic cations are improved through natural nano clay and industrial waste residues; 3) neutralizing H in soil by self-abundant amine groups+The three functions are synergistic to achieve the aim of restoring acid soil. The implementation of the project can effectively promote the improvement of the acid soil and provide effective scientific and technological support for the implementation of the high-quality development of agriculture and the village vogue strategy in China;
compared with the existing repairing agent, the acid soil repairing agent provided by the invention can obviously improve the pH value of soil and free Ca2 +Free Si content, reduces the loss of soil cations and has a radical effect on acid soil; compared with the existing repairing agent, the acid soil repairing agent provided by the invention can obviously improve the yield of corn, rice and wheat.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
Sources of raw materials used in the examples:
attapulgite clay: mingmei mineral chemical Co., Ltd. (model G-3), 100-plus 200 mesh;
red mud: 100-mesh, 200-mesh, pH 11.5, CaO 43.01% and SiO 22 20.51％、Al2O3 6.54％、Fe2O3 10.02％、Na2O 2.42％、K2O 0.39％、TiO22.45％、MgO 0.75％；
Biochar: jiangsu Huafeng agricultural bioengineering, Inc., rice husk charcoal, pH 9.3;
organic fertilizer: hebei Lingguang Biotech Co., Ltd., microbial organic fertilizer, organic matter > 50%.
Example 1
(1) Mixing attapulgite (100 meshes) and red mud (100 meshes) according to the proportion of 1: 3, and adding the mixture into water to obtain a mixed solution with the concentration of 100 g/L;
(2) adding sodium polyacrylate (5 g/L) into the mixed solution obtained in the step (1), and stirring at normal temperature (300rpm) for 3 hours;
(3) adding N-hydroxysuccinimide (2 g/l) and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride (1 g/l) to the mixed solution obtained in (2), adjusting the pH to 8.5 with a sodium carbonate and sodium bicarbonate buffer solution, and stirring (300rpm) at normal temperature for 8 hours;
(4) adding polyethyleneimine (with the molecular weight of 1600 and 10 g/L) into the solution obtained in the step (3), stirring at normal temperature (300rpm) for 10 hours, filtering, washing with 200mL of water for 3 times, drying at 50 ℃, and crushing to 100 meshes to obtain an acidic soil remediation agent;
(5) the repairing agent is uniformly spread on the surface of soil (pH6) according to 50 kg/mu, then rotary tillage is carried out, after 30 days, the pH of the soil can be increased by 1 unit, and free Ca is added2+The content is increased by 400mg/kg, the free Si content is increased by 400mg/kg, and the corn, the rice and the wheat are respectively increased by 80 kg/mu, 70 kg/mu and 90 kg/mu.
Example 2
(1) Mixing attapulgite (150 meshes) and red mud (150 meshes) according to the weight ratio of 2: 4, and adding the mixture into water to obtain a mixed solution with the concentration of 200 g/L;
(2) adding sodium polyacrylate (7.5 g/L) to the mixed solution obtained in (1), and stirring at normal temperature (400rpm) for 4 hours;
(3) to the mixed solution obtained in (2), N-hydroxysuccinimide (3 g/l) and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride (2 g/l) were added, and the pH was adjusted to 9 with a sodium carbonate and sodium hydrogencarbonate buffer solution, and stirred (400rpm) at normal temperature for 9 hours;
(4) adding polyethyleneimine (with the molecular weight of 1700 and 15 g/L) into the solution obtained in the step (3), stirring at normal temperature (400rpm) for 11 hours, filtering, washing with 300mL of water for 4 times, drying at 60 ℃, and crushing to 150 meshes to obtain an acid soil remediation agent;
(5) the repairing agent is uniformly spread on the surface of soil (pH 5) according to 75 kg/mu, then rotary tillage is carried out, and after 30 days, 2-unit free Ca for increasing the pH of the soil can be obtained2+The content is increased by 600mg/kg, the free Si content is increased by 500mg/kg, and the corn, the rice and the wheat are respectively increased by 100 kg/mu, 100 kg/mu and 120 kg/mu.
Example 3
(1) Mixing attapulgite (200 meshes) and red mud (200 meshes) according to the weight ratio of 3: 5, and adding the mixture into water to obtain a mixed solution with the concentration of 300 g/L;
(2) adding sodium polyacrylate (10 g/L) to the mixed solution obtained in (1), and stirring at normal temperature (500rpm) for 5 hours;
(3) to the mixed solution obtained in (2), N-hydroxysuccinimide (4 g/l) and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride (3 g/l) were added, and the pH was adjusted to 9.5 with a sodium carbonate and sodium hydrogencarbonate buffer solution, and the mixture was stirred (500rpm) at normal temperature for 10 hours;
(4) adding polyethyleneimine (with the molecular weight of 1800 and 20 g/L) into the solution obtained in the step (3), stirring at normal temperature (500rpm) for 12 hours, filtering, washing with 400mL of water for 5 times, drying at 70 ℃, and crushing to 200 meshes to obtain an acidic soil remediation agent;
(5) the repairing agent is uniformly spread on the surface of soil (pH4) according to 100 kg/mu, then rotary tillage is carried out, and after 30 days, the pH of the soil can be increased by 3 units and free Ca can be added2+The content is increased by 800mg/kg, the free Si content is increased by 600mg/kg, and the corn, the rice and the wheat are respectively increased by 150 kg/mu, 130 kg/mu and 160 kg/mu.
Table 1 shows the influence of different kinds of acid soil remediation agents on soil indexes
Table 1:
the detection method of each index comprises the following steps: pH of soil, free Ca2+And a detection method of free Si content: according to the water: dissolving soil in water according to the mass ratio of 5:1, shaking for 24h, centrifuging (12000rpm) for 10 min, filtering by using medium-speed filter paper to obtain supernatant, and measuring the pH value of the supernatant by using a pH meter to obtain the pH value of the soil; passing the supernatant through 0.45um filter membrane, and measuring free Ca in the supernatant by inductively coupled plasma spectrometer (ICP)2+And the content of free Si.
Table 2 shows the effect of different kinds of acid soil remediation agents on the yield of corn, rice and wheat.
Table 2:
Claims (8)
1. the soil repairing agent is characterized by comprising the following raw materials in parts by weight: 300 parts of attapulgite and red mud, 5-10 parts of sodium polyacrylate, 10-20 parts of polyethyleneimine, 1000 parts of water, 2-4 parts of N-hydroxysuccinimide and 1-3 parts of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride; the mass ratio of the attapulgite to the red mud is 1-3: 3-5;
the preparation method of the soil remediation agent comprises the following steps:
(1) uniformly mixing attapulgite and red mud, adding into water to obtain a mixed solution, adding sodium polyacrylate, and stirring at normal temperature for 3-5 h;
(2) adding N-hydroxysuccinimide and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride in the step (1), adjusting the pH value to 8.5-9.5, and stirring at normal temperature for 8-10 h;
(3) and (3) adding polyethyleneimine into the step (2), stirring for 10-12h at normal temperature, filtering, washing, drying and crushing to obtain the soil remediation agent.
2. The repairing agent as claimed in claim 1, wherein the attapulgite is of 100-200 meshes, and the red mud is of 100-200 meshes.
3. The repairing agent according to claim 1, wherein the raw material components comprise, in parts by weight: the coating comprises, by weight, 100 parts of attapulgite and red mud, 5 parts of sodium polyacrylate, 2 parts of N-hydroxysuccinimide, 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride, 10 parts of polyethyleneimine and 1000 parts of water.
4. The repairing agent according to claim 1, wherein the raw material components comprise, in parts by weight: 200 parts of attapulgite and red mud, 7.5 parts of sodium polyacrylate, 3 parts of N-hydroxysuccinimide, 2 parts of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride, 15 parts of polyethyleneimine and 1000 parts of water.
5. The repairing agent according to claim 1, wherein the raw material components comprise, in parts by weight: the coating comprises, by weight, 300 parts of attapulgite and red mud, 10 parts of sodium polyacrylate, 4 parts of N-hydroxysuccinimide, 3 parts of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride, 20 parts of polyethyleneimine and 1000 parts of water.
6. A method of preparing the soil remediation agent of claim 1, comprising:
(1) uniformly mixing attapulgite and red mud, adding into water to obtain a mixed solution, adding sodium polyacrylate, and stirring at normal temperature for 3-5 h;
(2) adding N-hydroxysuccinimide and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride in the step (1), adjusting the pH value to 8.5-9.5, and stirring at normal temperature for 8-10 h;
(3) and (3) adding polyethyleneimine into the step (2), stirring for 10-12h at normal temperature, filtering, washing, drying and crushing to obtain the soil remediation agent.
7. The method according to claim 6, wherein the pH is adjusted in the step (2) to: the pH was adjusted to 8.5-9.5 with sodium carbonate and sodium bicarbonate buffer solution.
8. Use of the soil remediation agent of claim 1 for acid soil remediation.
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| CN111943778B (en) * | 2020-08-20 | 2022-03-25 | 甘肃省农业科学院土壤肥料与节水农业研究所 | Organic agricultural acid soil potassium conditioner |
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| CN106966810A (en) * | 2017-04-25 | 2017-07-21 | 中国科学院合肥物质科学研究院 | A kind of anion response type controlled release selenium fertilizer, preparation method and application |
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| CN101463247B (en) * | 2007-12-21 | 2012-10-24 | 中国科学院沈阳应用生态研究所 | Composite type soil water retention agent and preparation |
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