CN108865149B - Soil heavy metal stabilizer based on natural macromolecules and preparation method thereof - Google Patents

Soil heavy metal stabilizer based on natural macromolecules and preparation method thereof Download PDF

Info

Publication number
CN108865149B
CN108865149B CN201810420023.6A CN201810420023A CN108865149B CN 108865149 B CN108865149 B CN 108865149B CN 201810420023 A CN201810420023 A CN 201810420023A CN 108865149 B CN108865149 B CN 108865149B
Authority
CN
China
Prior art keywords
chitosan
lignin
heavy metal
humic acid
lignosulfonate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810420023.6A
Other languages
Chinese (zh)
Other versions
CN108865149A (en
Inventor
韩永萍
李海燕
陈白阳
韩佳文
段炫彤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing Union University
Original Assignee
Beijing Union University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beijing Union University filed Critical Beijing Union University
Priority to CN201810420023.6A priority Critical patent/CN108865149B/en
Publication of CN108865149A publication Critical patent/CN108865149A/en
Application granted granted Critical
Publication of CN108865149B publication Critical patent/CN108865149B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • C09K17/00—Soil-conditioning materials or soil-stabilising materials
    • C09K17/14—Soil-conditioning materials or soil-stabilising materials containing organic compounds only
    • C09K17/18—Prepolymers; Macromolecular compounds
    • C09K17/32—Prepolymers; Macromolecular compounds of natural origin, e.g. cellulosic materials
    • 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
    • C09K2101/00—Agricultural use

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Soil Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Soil Conditioners And Soil-Stabilizing Materials (AREA)
  • Processing Of Solid Wastes (AREA)
  • Polysaccharides And Polysaccharide Derivatives (AREA)

Abstract

The invention discloses a soil heavy metal stabilizer based on natural macromolecules and a preparation method thereof. The chitosan with deacetylation degree of 70% -90% and humic acid and lignin dissolved in a water solution with pH value of more than or equal to 10 are used as raw materials, and the chitosan-lignin composite material is prepared by glutaraldehyde step-by-step crosslinking and intermolecular interpenetrating network polymerization, wherein the mass ratio of the dosage of each component is chitosan: humic acid: lignin or lignosulfonate: glutaraldehyde is 1-6: 1-3: 0-6: 0.5 to 1.0. The preparation method is simple to operate and safe in operating environment, and the obtained natural polymer soil heavy metal stabilizer is remarkably improved in the aspect of stabilizing the heavy metal performance of soil.

Description

Soil heavy metal stabilizer based on natural macromolecules and preparation method thereof
Technical Field
The invention belongs to a soil heavy metal stabilizer, and particularly relates to soil heavy metal P based on natural macromoleculesbAnd CdA stabilizer and a preparation method thereof.
Background
With the acceleration of industrialization and urbanization processes, the problem of heavy metal pollution to the environment of soil is particularly prominent. Wherein, lead (P)b) The heavy metal is a multi-affinity heavy metal, belongs to persistent pollutants in soil, is mainly accumulated by crop grains, and endangers human health through a food chain. PbOnce entering the body, brain tissue damage can be caused by invasion of brain nerve tissue, and children in growth and development stage can be caused to develop slowly, move more, and have low intelligence. Phase contrast PbIn other words, cadmium (C) in the soild) Is easier to be leached, not only causes the nuisance of pain, but also can cause the damage to the liver and kidney organs of the human body. It is reported that China CdAbout 1.3 kilohm of polluted farmland225 regions relating to 11 provinces; the grain contains more than 11 production areas containing more than 1.0mg/kg of Pb and the soil PbThe content is up to 1143 mg/kg. Therefore, the P in the soil is scientifically and effectively controlledbAnd CdThe release and transfer of (2) has become a real problem to be solved urgently.
The crops have a certain growth cycle. Taking rice as an example, the growth period is generally 150-180 d and is divided into two stages of vegetative growth and reproductive growth. Researches show that the absorption and transportation of heavy metals by crops mainly occur in the active metabolic stage, and the grain filling stage and heading stage of reproductive growth of rice are slightly higher than the tillering stage of vegetative growth. Therefore, the heavy metal in the soil environment of the plant roots can be effectively stabilized in the growth period of crops, so that the accumulation of the heavy metal absorbed by the crop roots and entering stems and leaves or seeds can be reduced, and the way that the heavy metal enters human bodies from food chains to cause harm to human health is cut off.
Disclosure of Invention
The invention aims to provide a preparation method of a soil heavy metal stabilizer based on natural macromolecules, which is simple to operate and safe in operating environment, the prepared soil heavy metal stabilizer has a good stabilizing effect on Pb and Cd in soil, and the used raw materials also have the characteristics of improving the soil and even promoting the growth of plants.
The invention also aims to provide the soil heavy metal stabilizer with the characteristic of time-limited stability, which is prepared by the method, wherein chitosan, humic acid and lignin are used as raw materials, and the soil heavy metal stabilizer is prepared by glutaraldehyde step-by-step crosslinking and intermolecular interpenetrating network polymerization.
In order to achieve the aim, the invention provides a preparation method of a natural polymer-based soil heavy metal stabilizer, which comprises the following steps:
(1) placing chitosan with deacetylation degree of 70-90% in acetic acid solution with deacetylation degree of 1-3 vt%, wherein the mass concentration of chitosan in acetic acid solution is 1-3 wt%, stirring at room temperature for 0.5-1.5 h, and stirring at 80-100rpm to fully swell chitosan;
(2) dissolving humic acid and lignin or lignosulfonate in water with pH of more than or equal to 10, and filtering to remove undissolved substances, wherein the mass concentration of the humic acid is 0.5-1.5 wt%, and the mass concentration of the lignin or lignosulfonate is 0-3 wt%;
since humic acid and lignin or lignosulfonate are insoluble in acidic or neutral water and soluble only in alkaline water, water having a pH of 10 or more is used to dissolve humic acid and lignin or lignosulfonate.
(3) Heating the fully swollen chitosan solution obtained in the step (1) to 65-85 ℃ in a water bath under the stirring of 80-100rpm, dripping a glutaraldehyde solution with the mass concentration of 10 vt% for 20-30 min, dripping a humic acid and lignin or lignosulfonate aqueous solution prepared in the step (2) for 5-10 min, dripping a glutaraldehyde solution with the mass concentration of 10 vt%, wherein the 10 vt% glutaraldehyde solution dripped in the previous step and the 10 vt% glutaraldehyde solution dripped in the next step have the same volume, and stirring and reacting for 4-8 h at the temperature of 65-85 ℃ after the dripping is finished to obtain slurry;
the first glutaraldehyde is to pre-crosslink chitosan to form gel skeleton, and the second glutaraldehyde is to crosslink humic acid, lignin and chitosan.
As the chitosan is dissolved under the acidic condition (acetic acid solution), the lignin is dissolved under the alkaline condition (water with pH more than or equal to 10), the pH range of humic acid is wide, the pH of the reaction system is increased due to humic acid and lignin alkaline solution added in the later period, part of chitosan becomes gel and is subjected to partial heterogeneous cross-linking with the lignin, and interpenetrating network cross-linking is carried out on part of soluble humic acid molecules, the chitosan and the lignin.
(4) And (3) adding the slurry prepared in the step (3) into ethanol solution of acetic acid with the same volume of 1 vt% -3 vt%, soaking for 1-2 h, filtering, repeating the operation for 3-4 times, then washing with deionized water to be neutral, filtering, adding the prepared slurry into saturated sodium bicarbonate solution with the same volume of the slurry, soaking overnight, filtering, washing with deionized water to be neutral, filtering, and drying at 70-90 ℃ to constant weight.
Wherein the mass ratio of chitosan, humic acid, lignin or lignosulfonate and glutaraldehyde is as follows: and (3) chitosan: humic acid: lignin or lignosulfonate: glutaraldehyde is 1-6: 1-3: 0-6: 0.5 to 1.0.
Preferably, the lignosulfonate is sodium lignosulfonate.
The invention also provides the natural polymer soil heavy metal stabilizer prepared by the method.
According to the soil heavy metal stabilizer based on the natural polymer, firstly, glutaraldehyde is used for carrying out primary crosslinking on chitosan with the deacetylation degree of 70% -90%, then the chitosan is continuously crosslinked with humic acid and lignin, and a polymer based on the natural polymer is obtained through an intermolecular crosslinking and interpenetrating network method.
The chitosan is a product obtained by deacetylating chitin in shells of shrimps, crabs and insects, has good biodegradability, can promote plant growth, shows strong adsorption performance to heavy metals due to the fact that the structure is rich in active amino and hydroxyl, and meanwhile has certain antibacterial property.
The chitosan with the deacetylation degree of 70-90% is selected, because the chitosan with the deacetylation degree of less than 70% has less active group amino content, glutaraldehyde crosslinking is difficult, and the chitosan with the deacetylation degree of more than 90% has excessively high amino content in a molecular structure, so that a serious self-crosslinking phenomenon can be generated, and the crosslinking chance of the chitosan, the glutaraldehyde, humic acid and lignin is influenced.
Humic acid is used as a main component of soil organic matters, has a loose sponge structure and a plurality of functional groups such as carboxyl, phenolic hydroxyl, aldehyde group and the like, and is mostly used as a fertilizer and a soil conditioner.
Lignin is a polyphenolic macromolecule widely present in plant cell walls, and is second only to cellulose, accounting for about 20% of the total plant weight. The alkali lignin is a main byproduct of papermaking raw materials such as wood, bamboo, grass and the like, and has a large amount of functional groups capable of being combined with heavy metals such as methoxy, hydroxyl, carbonyl and the like in the structure, and the alkali lignin is rich in sources and has development value in the aspects of heavy metal adsorption and stability.
According to the natural polymer-based soil heavy metal stabilizer provided by the invention, chitosan with deacetylation degree of 70-90% and humic acid and lignin dissolved in water with pH value of more than or equal to 10 are taken as basic materials for cross-linking polymerization, on one hand, the stabilizer has high stability capacity on various heavy metals through a plurality of adsorption active sites and spatial structures, and is mainly used for stabilizing heavy metals of Pb and Cd in soil; and the other side can keep the stability time of the macromolecular stabilizer in the soil by utilizing the cross-linking reaction and the bacteriostatic property of the chitosan so as to prevent the macromolecular stabilizer from being degraded by various microorganisms in the soil in a short time.
The natural polymer soil heavy metal stabilizer prepared by the preparation method has a certain space network structure due to the introduction of heavy metal adsorption active sites with different structures, and simultaneously has a good stabilizing effect on various heavy metals in soil, especially on P in soilbAnd CdThe stabilizing efficiency is improved by nearly 1 time, and the stabilizing time is improved by nearly 5 times. In addition, the prepared soil heavy metal stabilizer can not cause secondary pollution to the environment after being degraded by the environment, and can also become a soil fertilizer or a plant growth promoting factor.
The preparation method of the natural polymer soil heavy metal stabilizer provided by the invention is simple to operate and safe in operating environment, and the obtained natural polymer is obviously improved in the aspect of soil heavy metal stability.
Drawings
FIG. 1A is an electron micrograph (. times.10.00K) of humic acid.
FIG. 1B is an electron micrograph of chitosan (. times.10.00K).
FIG. 1C is an electron micrograph of lignin (. times.10.00K).
FIG. 1D is an electron microscope scanning image (x 10.00K) of the soil heavy metal stabilizer based on natural polymer prepared by the invention.
FIG. 2 is an infrared spectrum of humic acid, chitosan, lignin and the soil heavy metal stabilizer based on natural macromolecules prepared by the invention.
Detailed Description
Example 1
Adding 1.0g of humic acid into water, adjusting the pH to 11.5 by using 1 wt% of NaOH aqueous solution, and stirring to dissolve until the concentration of the humic acid is 1 wt%; 2.0g of lignin is continuously added into the humic acid solution, stirred and dissolved to ensure that the concentration of the lignin is 1 wt%, and filtered for later use.
2.0g of chitosan oligosaccharide having a degree of deacetylation of 80% was dissolved in 4 vt% acetic acid solution to a chitosan concentration of 2 wt%, placed in a three-necked flask equipped with a stirrer, mixed well, stirred at 80rpm, and swollen for 1.0 h. Heating in water bath to 80 ℃, dropwise adding 7.5ml of 10 vt% glutaraldehyde solution under stirring, dropwise adding the prepared humic acid and lignin solution, dropwise adding 7.5ml of 10 vt% glutaraldehyde solution after finishing dropwise adding for 10min, and reacting for 5h under constant temperature stirring at 80 ℃.
Taking out the reaction slurry, filtering, soaking the intercepted substance in 1.53 vt% acetic acid solution, stirring and washing for 3-4 times; repeatedly washing with deionized water to neutrality, and filtering; and soaking the soil in saturated sodium bicarbonate solution with the same volume as the prepared slurry overnight, filtering, washing with deionized water to be neutral, filtering, and drying at 90 ℃ to constant weight to obtain the soil heavy metal stabilizer based on the natural polymer.
Example 2 determination of chemical Properties of soil heavy Metal stabilizer
1. Apparent structure
Scanning humic acid, chitosan, lignin and prepared soil heavy metal stabilizer based on natural macromolecules under an electron microscope, and the figures are shown in fig. 1A to fig. 1D.
As can be seen from FIG. 1A, humic acid has a rough surface and a loose structure; as can be seen from FIGS. 1B and 1C, the chitosan and lignin have a relatively dense, gel-like structure. As can be seen from FIG. 1D, compared with humic acid, the prepared soil heavy metal stabilizer has a relatively uniform structure and good integrity; compared with chitosan and lignin, the structure is obviously loose, the mesh structure is rich, the specific area is large, and the heavy metal adsorption capacity is large.
2. Structural characterization of infrared spectra
The infrared spectrogram of humic acid, chitosan, lignin and the soil heavy metal stabilizer based on natural macromolecules prepared by the invention is shown in figure 2, and can be seen as follows:
3500～3300cm-1is the stretching vibration absorption peak of carboxyl, phenolic hydroxyl, alcoholic hydroxyl and amino, 1600cm-1Is a characteristic peak of benzene ring C ═ C, 2874cm-1Is a characteristic peak of methylene C-H，1367cm-1Is a characteristic peak of-COOH, 1075cm-1Is a C-OH characteristic peak of 1645cm-1And 1599cm-1Is a characteristic peak of amino-N-H. As can be seen from fig. 2, lignin, chitosan and humic acid all contain a large amount of polar groups such as carboxyl, hydroxyl or amino groups, besides aromatic groups.
The stabilizer obtained after glutaraldehyde crosslinking is 1015cm higher than humic acid and lignin-1C-O in the position is obviously increased and is 3500-3300 cm-1And 1075cm-1The characteristic peak of C-OH becomes smaller. Indicating that glutaraldehyde reacts with-OH in humic acid and lignin to generate C-O-C. Compared with chitosan, the stabilizer is 1599cm-1The characteristic peak of amino-N-H disappears at 1630cm-1The characteristic peaks on the left and right become wider, which indicates that glutaraldehyde reacts with amino groups in chitosan to generate a certain amount of C-N, and the C-N characteristic peaks cover the limited amount of C-N. Thus, glutaraldehyde forms lignin, chitosan and humic acid into a polymer through cross-linking and interpenetrating networks.
3. Soil heavy metal stability test
Test soil: is taken from a grass garden of a college, is naturally dried and is sieved by a sieve of 80 meshes. Spraying 0.3g/L lead nitrate and nitric acid isolation solution into the soil to be tested for multiple times to enable the content of Pb and Cd in the soil to be about 100mg/kg, uniformly mixing, adding water for wetting to enable the water content to be 10%, sealing, and aging for 15 days at 25-30 ℃ for later use.
Stabilization experiments: respectively adding chitosan, humic acid, lignin and a prepared soil heavy metal stabilizer based on natural macromolecules into soil to be tested to enable the content of the soil heavy metal stabilizer to be 1.0g/kg, uniformly mixing, keeping a wet state, stabilizing at room temperature under a dark condition, taking 10g of soil sample after a certain time, carrying out a leaching toxicity test according to TCLP, measuring the content of Pb and Cd in a leaching solution by using an inductive coupling plasma spectrum generator (Thermo iCAP 6300, ICP), and calculating the stabilizing efficiency eta (%).
Figure BDA0001650469910000052
In the formula C0And CsThe concentrations of Pb and Cd in the soil leachate are measured before and after adding the stabilizer.
Stabilizing efficiency of different stabilizers on Pb and Cd in soil after 30d and 180d
Figure BDA0001650469910000053
And
Figure BDA0001650469910000054
see table 1.
The data in table 1 show that the soil heavy metal stabilizer based on natural macromolecules prepared by crosslinking chitosan, humic acid and lignin has obviously enhanced stabilizing efficiency on Pb and Cd in soil, and the stability of the soil heavy metal stabilizer is kept good under natural conditions.
TABLE 1
Figure BDA0001650469910000051
Wherein 180d is substantially close to the growth cycle of a crop.
It should be noted that the invention does not permanently stabilize the heavy metal in the soil, but stabilizes the heavy metal around the root system of the crop during the growth period of the crop and prevents the heavy metal from being absorbed by the crop. In the later period of crop maturity, the stabilizing agent of the present invention will be gradually degraded into fertilizer to promote crop growth. Therefore, heavy metals in the crop body are limited in the root system or the straw, and the heavy metals are prevented from entering grains of the crop, so that harm to eaters is avoided.
It can be seen from the above examples that the soil heavy metal stabilizer based on natural polymer and the preparation method thereof provided by the invention can be used for complexing heavy metal P in soil under natural conditions through actions such as hydrogen bonds and the likebAnd CdStable for 3-5 months, thereby limiting the P pair of crops in the growing periodbAnd CdAbsorption of (2). Then, along with the degradation of the heavy metal stabilizer in the natural environment, the chitosan, humic acid, lignin or lignosulfonate or residues thereof in the composition are dispersed into the soil, so that the plant growth promotion and soil improvement performance can be fully exerted.

Claims (3)

1. A preparation method of a soil heavy metal stabilizer based on natural macromolecules is characterized by comprising the following steps: the method comprises the following steps:
(1) placing chitosan with deacetylation degree of 70-90% in acetic acid solution with deacetylation degree of 1-3 vt%, wherein the mass concentration of chitosan in acetic acid solution is 1-3 wt%, stirring at room temperature for 0.5-1.5 h, and stirring at 80-100rpm to fully swell chitosan;
(2) dissolving humic acid and lignin or lignosulfonate in water with pH of more than or equal to 10, and filtering to remove undissolved substances, wherein the mass concentration of the humic acid is 0.5-1.5 wt%, and the mass concentration of the lignin or lignosulfonate is 0-3 wt%;
(3) heating the fully swollen chitosan solution obtained in the step (1) to 65-85 ℃ in a water bath under the stirring of 80-100rpm, dripping a glutaraldehyde solution with the mass concentration of 10 vt% for 20-30 min, dripping a humic acid and lignin or lignosulfonate aqueous solution prepared in the step (2) for 5-10 min, dripping a glutaraldehyde solution with the mass concentration of 10 vt%, wherein the 10 vt% glutaraldehyde solution dripped in the previous step and the 10 vt% glutaraldehyde solution dripped in the next step have the same volume, and stirring and reacting for 4-8 h at the temperature of 65-85 ℃ after the dripping is finished to obtain slurry;
(4) adding ethanol solution of acetic acid with the same volume of 1 vt% -3 vt% into the slurry prepared in the step (3) to soak for 1-2 h, filtering, repeating the operation for 3-4 times, then washing the slurry with deionized water to be neutral, filtering, adding saturated sodium bicarbonate solution with the same volume of the prepared slurry to soak overnight, filtering, washing the slurry with deionized water to be neutral, and drying the slurry at 70-90 ℃ to constant weight after filtering;
wherein the mass ratio of chitosan, humic acid, lignin or lignosulfonate and glutaraldehyde is as follows: and (3) chitosan: humic acid: lignin or lignosulfonate: glutaraldehyde is 1-6: 1-3: 0-6: 0.5 to 1.0.
2. The method of claim 1, wherein the lignosulfonate is sodium lignosulfonate.
3. A soil heavy metal stabilizer prepared by the method of claim 1 or 2.
CN201810420023.6A 2018-05-04 2018-05-04 Soil heavy metal stabilizer based on natural macromolecules and preparation method thereof Active CN108865149B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810420023.6A CN108865149B (en) 2018-05-04 2018-05-04 Soil heavy metal stabilizer based on natural macromolecules and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810420023.6A CN108865149B (en) 2018-05-04 2018-05-04 Soil heavy metal stabilizer based on natural macromolecules and preparation method thereof

Publications (2)

Publication Number Publication Date
CN108865149A CN108865149A (en) 2018-11-23
CN108865149B true CN108865149B (en) 2020-09-29

Family

ID=64327564

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810420023.6A Active CN108865149B (en) 2018-05-04 2018-05-04 Soil heavy metal stabilizer based on natural macromolecules and preparation method thereof

Country Status (1)

Country Link
CN (1) CN108865149B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111662727B (en) * 2020-07-17 2021-04-23 北京市环境保护科学研究院 Improver for soil polluted by primary explosive

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105315084A (en) * 2015-11-27 2016-02-10 安徽帝元生物科技有限公司 Synergistic environment-friendly fertilizer aid and fertilizer
CN105733596A (en) * 2016-03-21 2016-07-06 中国科学院烟台海岸带研究所 Soil conditioner for passivation of heavy metals and preparation method of soil conditioner

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105315084A (en) * 2015-11-27 2016-02-10 安徽帝元生物科技有限公司 Synergistic environment-friendly fertilizer aid and fertilizer
CN105733596A (en) * 2016-03-21 2016-07-06 中国科学院烟台海岸带研究所 Soil conditioner for passivation of heavy metals and preparation method of soil conditioner

Also Published As

Publication number Publication date
CN108865149A (en) 2018-11-23

Similar Documents

Publication Publication Date Title
Elbarbary et al. Radiation induced crosslinking of polyacrylamide incorporated low molecular weights natural polymers for possible use in the agricultural applications
KR101031365B1 (en) Biodegradable compositions for liquid mulching, a method for preparing the same and a method for mulching using the same
CN108752130B (en) Plant-growing soil water-retaining agent for slope greening ecological restoration and preparation method thereof
AU2012294596B2 (en) Wettable, non-leachable peat moss, method of preparation, and method of use
CN103039473A (en) High-efficiency seed coating
Huey et al. Allicin incorporation as urease inhibitor in a chitosan/starch based biopolymer for fertilizer application
CN107586403A (en) A kind of γ polyglutamic acids chitosan gel rubber and its preparation method and application
CN112521219A (en) Biomass-based pesticide-fertilizer liquid mulching film and preparation method and application thereof
CN108865149B (en) Soil heavy metal stabilizer based on natural macromolecules and preparation method thereof
CN111995463A (en) Spraying production process of mineral source potassium fulvate compound fertilizer
KR101285792B1 (en) Fertillizer composition comprising silicic acid, chitosan and humic acid, and manufacturing method thereof
CN101019559B (en) Plant growth promoter and its use
CN101519475A (en) Method for preparing rotenone/carboxymethyl chitosan grafting ricinoleic acid nanometer grain water dispersing agent
Suratman et al. Controlled release fertilizer encapsulated by glutaraldehyde-crosslinked chitosan using freeze-drying method
Zhang et al. Sodium alginate/sodium lignosulfonate hydrogel based on inert Ca2+ activation for water conservation and growth promotion
CN102487963B (en) Agricultural bactericide containing rare-earth elements and chitosan and/or derivatives of chitosan
CN111303894B (en) Lignin-based composite stabilizer for in-situ remediation of heavy metal pollution in soil and preparation method thereof
Peña-Datoli et al. Maize (Zea mays L.) seed coating with chitosan and sodium alginate and its effect on root development
CN106047359A (en) Water-retaining agent used for saline-alkali soil wheat and containing animal waste raw material and preparation method thereof
CN107815050A (en) A kind of Biodegradable film, its preparation method and include its mulch film
Zhang et al. Waste feather keratin composited geopolymer hydrogels for improving plant water retention and N nutrients utilization
CN111187116A (en) Preparation and application of straw sustained-release agent
CN114892444B (en) Paper-based mulching film and preparation method and application thereof
CN115650791B (en) Multifunctional slow release agent for soil and preparation method thereof
CN114711101B (en) Application of vegetable transplanting water-retaining agent in vegetable transplanting

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant