Preparation method and application of fulvic acid humus saline alkali soil remediation material

Abstract

The invention provides a preparation method and application of a fulvic acid humus saline alkali soil remediation material, and relates to the technical field of soil remediation. According to the preparation method of the fulvic acid humus saline alkali soil remediation material, nano-porous silicon oxide and nano cubic fulvic acid humus are adopted, the nano-porous silicon oxide serves as a carrier, the nano cubic fulvic acid humus serves as a remediation component, and a hydrothermal-impregnation method is adopted for preparation; by taking the mass of the nano-porous silicon oxide carrier as a reference, the mass percentage of the repairing component is 40%-60%. According to the remediation material, silicon oxide and humus are both original components in natural environment soil and cannot cause secondary pollution to saline-alkali soil after being doped into the soil, and the nano porous silicon oxide carrier can adsorb the nano cube fulvic acid humus in the preparation process of the remediation material and can also adsorb the nano cube fulvic acid humus in the preparation process of the remediation material; and after fulvic acid colonies are completely released, alkali metal ions such as sodium and potassium can be adsorbed, so that the dual effects of reducing salt and increasing fertility of the saline-alkali soil are realized.

Description

Technical Field

[0001] The invention relates to the technical field of soil remediation, and in particular to a preparation method and application of a fulvic acid humus saline-alkali soil remediation material. Background Art

[0002] Saline-alkali land is widely distributed in many arid, semi-arid and water-mismanaged areas around the world, especially in some countries where soil salinization is serious. According to the Global Land Degradation Report, about 23% of the world's arable land is affected by salinization. The series of problems caused by saline-alkali land include: limited crop growth, the high salt and alkaline environment in saline-alkali land will inhibit the normal growth of plants, especially affecting the absorption of water and the acquisition of nutrients; soil structure is destroyed, excessive salt will affect the soil's aggregate structure, leading to soil hardening, poor air permeability and water permeability, further aggravating the lack of water and nutrients; the ecological environment deteriorates, salinized land usually cannot support biodiversity, causing the degradation of ecosystem functions.

[0003] In recent years, with the rapid development of new technologies such as bioremediation technology, microbial regulation, chemical conditioners, and the cultivation of salt-tolerant plant varieties, research on saline-alkali land restoration has made certain progress. For example: plant restoration technology, by planting salt-tolerant plants or performing plant genetic engineering to improve them so that they can grow in a saline-alkali environment, and regulate soil salinity through plant growth; microbial restoration technology: using specific microorganisms, such as bacteria and fungi, to degrade or convert soil salt; soil conditioners: using organic matter, mineral conditioners, etc. to change the physical and chemical properties of the soil, increase soil permeability and fertility. Therefore, technicians in this field provide a preparation method and application of a fulvic acid humus saline-alkali soil restoration material to solve the problems raised in the above technical scheme. Summary of the invention

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the present invention provides a method for preparing a fulvic acid humus saline-alkali soil remediation material and its application, which solves the problem that the soil remediation material can not only increase soil fertility, but also improve the soil aggregate structure and provide persistent management during the saline-alkali soil remediation process.

[0006] (II) Technical solution

[0007] To achieve the above purpose, the present invention is implemented by the following technical scheme: a preparation method of a fulvic acid humus saline-alkali soil repair material, comprising nanoporous silica and nano-cubic fulvic acid humus, with nanoporous silica as a carrier and nano-cubic fulvic acid humus as a repair component, and prepared by a hydrothermal-impregnation method; based on the mass of the nanoporous silica carrier, the mass percentage of the repair component is 40% to 60%, and the specific preparation method comprises the following steps:

[0008] S1. Preparation of nanoporous silicon oxide, weighing silicon salt, carrier morphology control agent, ethanol and deionized water, mixing them evenly, and then placing them in a hydrothermal reactor for hydrothermal reaction, filtering and drying after the reaction, and then calcining at high temperature to obtain nanoporous silicon oxide particles, and then placing the nanoporous silicon oxide particles in a plasma surface treatment instrument, first evacuating the plasma surface treatment instrument, then filling it with oxygen, and then performing surface treatment to obtain surface-modified nanoporous silicon oxide;

[0009] S2. Preparation of nano-cube fulvic acid humus, weigh lignite, extractant and deionized water, mix them evenly and oscillate them on a constant temperature oscillator, then centrifuge to separate the supernatant, add hydrochloric acid to the supernatant until the pH is 1 to 2, let it stand and filter it with a polyethersulfone aqueous phase filter membrane to obtain a secondary supernatant, add a repair component morphology control agent to the secondary supernatant and place it in a hydrothermal reactor for low-temperature hydrothermal reaction, and dry it after completion to obtain nano-cube fulvic acid humus;

[0010] S3. Preparation of saline-alkali soil remediation materials: weigh the surface-modified nanoporous silica prepared in step S1 and the nanocubic fulvic acid humus prepared in step S2, mix them evenly with deionized water, and stir them in a water bath until dry to obtain saline-alkali soil remediation materials.

[0011] Preferably, the silicon salt in step S1 is tetraethyl orthosilicate or butyl orthosilicate, and the carrier morphology control agent is 2-aminoethanesulfinic acid.

[0012] Preferably, in step S1, the mass ratio of silicon salt, carrier morphology control agent, ethanol and deionized water is 1:0.05-0.10:30-60:5-10.

[0013] Preferably, in step S1, the temperature of the hydrothermal reaction is 140 to 160 degrees Celsius, the time of the hydrothermal reaction is 6 to 12 hours, the temperature of the drying is 80 to 100 degrees Celsius, the time of the drying is 6 to 12 hours, the temperature of the high-temperature calcination is 500 to 600 degrees Celsius, and the time of the high-temperature calcination is 2 to 4 hours.

[0014] Preferably, the plasma surface treatment instrument in step S1 is a Plasma clean-PL-5010 model, the input voltage during surface treatment is 220V, the working distance is 5 to 12mm, and the plasma flame scanning rate is 20 to 100mm / s.

[0015] Preferably, in step S1, the volume ratio of oxygen to nanoporous oxide particles is 1:20-40.

[0016] Preferably, the extractant in step S2 is sodium hydroxide or potassium hydroxide, the mass ratio of lignite, extractant and deionized water is 1:0.2-0.5:40-60, hydrochloric acid is a hydrochloric acid solution with a mass fraction of 10% to 15%, the repair component morphology controller in step S2 is thioacetic acid, the mass ratio of the secondary supernatant and the repair component morphology controller is 1:0.01-0.05, the temperature of the low-temperature hydrothermal reaction is 100 to 110 degrees Celsius, the time of the low-temperature hydrothermal reaction is 2 to 4 hours, the drying temperature is 40 to 60 degrees Celsius, and the drying time is 12 to 24 hours.

[0017] Preferably, the temperature of the constant temperature oscillator in step S2 is 30 to 40 degrees Celsius, the oscillation time is 8 to 12 hours, the oscillation rate is 200 to 300 r / min, the standing time is 6 to 12 hours, and the pore size of the polyethersulfone aqueous phase filter membrane is 0.2 to 0.45 μm.

[0018] Preferably, in step S3, the mass ratio of the surface-modified nanoporous silica to deionized water is 1:20-30, and the stirring temperature in the water bath is 30 to 40 degrees Celsius.

[0019] The method for preparing a fulvic acid humus saline-alkali soil remediation material according to claims 1 to 9 is used in the field of soil remediation, and the soil remediation specifically refers to the remediation of saline-alkali soil.

[0020] (III) Beneficial effects

[0021] The present invention provides a preparation method and application of a fulvic acid humus saline-alkali soil repair material, which has the following beneficial effects:

[0022] 1. In the present invention, the silicon oxide and humus of the repair material are both original components in the soil of the natural environment. They will not cause secondary pollution to the saline-alkali soil when added to the soil. The nanoporous silicon oxide carrier can not only adsorb the nano-cubic fulvic acid humus during the preparation of the repair material, but also adsorb alkali metal ions such as sodium and potassium after the fulvic acid humus is released, thereby achieving the dual effects of reducing salt and increasing fertilizer in saline-alkali soil.

[0023] 2. In the present invention, the nano-cube fulvic acid humus has high purity and good effect. It can be slowly released in saline-alkali soil due to the action of hydroxyl groups in the nano-porous silica carrier, achieving a lasting treatment effect. The repair material is not only simple in process and low in price, but also can achieve lasting repair of saline-alkali soil, increase its organic matter content and soil fertility, and has high economic value and broad market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the FE-SEM of the surface-modified nanoporous silica carrier prepared in Example 1 of the present invention;

[0025] Figure 2 This is a schematic TEM diagram of the nanocube fulvic acid humus prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Embodiment 1:

[0028] like Figure 1-2 As shown, the embodiment of the present invention provides a method for preparing a fulvic acid humus saline-alkali soil repair material, comprising nanoporous silicon oxide and nano-cubic fulvic acid humus, with nanoporous silicon oxide as a carrier and nano-cubic fulvic acid humus as a repair component, and is prepared by a hydrothermal-impregnation method; based on the mass of the nanoporous silicon oxide carrier, the mass percentage of the repair component is 40% to 60%, and the specific preparation method comprises the following steps:

[0029] S1. Preparation of nanoporous silicon oxide, weighing silicon salt, carrier morphology control agent, ethanol and deionized water, mixing them evenly, and then placing them in a hydrothermal reactor for hydrothermal reaction, filtering and drying after the reaction, and then calcining at high temperature to obtain nanoporous silicon oxide particles, and then placing the nanoporous silicon oxide particles in a plasma surface treatment instrument, first evacuating the plasma surface treatment instrument, then filling it with oxygen, and then performing surface treatment to obtain surface-modified nanoporous silicon oxide;

[0030] S2. Preparation of nano-cube fulvic acid humus, weigh lignite, extractant and deionized water, mix them evenly and oscillate them on a constant temperature oscillator, then centrifuge to separate the supernatant, add hydrochloric acid to the supernatant until the pH is 1 to 2, let it stand and filter it with a polyethersulfone aqueous phase filter membrane to obtain a secondary supernatant, add a repair component morphology control agent to the secondary supernatant and place it in a hydrothermal reactor for low-temperature hydrothermal reaction, and dry it after completion to obtain nano-cube fulvic acid humus;

[0031] S3. Preparation of saline-alkali soil remediation materials: weigh the surface-modified nanoporous silica prepared in step S1 and the nanocubic fulvic acid humus prepared in step S2, mix them evenly with deionized water, and stir them in a water bath until dry to obtain saline-alkali soil remediation materials.

[0032] The silicon salt in step S1 is tetraethyl orthosilicate or butyl orthosilicate, and the carrier morphology control agent is 2-aminoethanesulfinic acid.

[0033] In step S1, the mass ratio of silicon salt, carrier morphology control agent, ethanol and deionized water is 1:0.05-0.10:30-60:5-10.

[0034] In step S1, the temperature of the hydrothermal reaction is 140 to 160 degrees Celsius, the time of the hydrothermal reaction is 6 to 12 hours, the temperature of the drying is 80 to 100 degrees Celsius, the time of the drying is 6 to 12 hours, the temperature of the high-temperature calcination is 500 to 600 degrees Celsius, and the time of the high-temperature calcination is 2 to 4 hours.

[0035] The plasma surface treatment instrument in step S1 is Plasmaclean-PL-5010 model. During surface treatment, the input voltage is 220V, the working distance is 5 to 12mm, and the plasma flame scanning rate is 20 to 100mm / s.

[0036] In step S1, the volume ratio of oxygen to nanoporous oxide particles is 1:20-40.

[0037] The extractant in step S2 is sodium hydroxide or potassium hydroxide, the mass ratio of lignite, extractant and deionized water is 1:0.2~0.5:40~60, the hydrochloric acid is a hydrochloric acid solution with a mass fraction of 10% to 15%, the repair component morphology controller in step S2 is thioacetic acid, the mass ratio of the secondary supernatant and the repair component morphology controller is 1:0.01~0.05, the temperature of the low-temperature hydrothermal reaction is 100 to 110 degrees Celsius, the time of the low-temperature hydrothermal reaction is 2 to 4 hours, the drying temperature is 40 to 60 degrees Celsius, and the drying time is 12 to 24 hours.

[0038] The temperature of the constant temperature oscillator in step S2 is 30 to 40 degrees Celsius, the oscillation time is 8 to 12 hours, the oscillation rate is 200 to 300 r / min, the standing time is 6 to 12 hours, and the pore size of the polyethersulfone aqueous phase filter membrane is 0.2 to 0.45 μm.

[0039] The mass ratio of the surface-modified nanoporous silica to deionized water in step S3 is 1:20-30, and the stirring temperature of the water bath is 30 to 40 degrees Celsius.

[0040] The method for preparing a fulvic acid humus saline-alkali soil remediation material according to claims 1 to 9 is used in the field of soil remediation, and the soil remediation specifically refers to the remediation of saline-alkali soil.

[0041] Embodiment 2:

[0042] S1. Preparation of nanoporous silica:

[0043] Weigh 6.935g of tetraethyl orthosilicate, 0.347g of 2-aminoethanesulfinic acid, 416.1g of ethanol, and 34.675g of deionized water, mix them evenly, then place them in a hydrothermal reactor for hydrothermal reaction at 140°C for 12h, filter them after the reaction, place them in an oven for drying at 80°C for 12h, and then place them in a muffle furnace for high-temperature roasting at 600°C for 2h to obtain nanoporous silicon oxide particles, then take 1mL of nanoporous silicon oxide particles and place them in a plasma surface treatment instrument, first evacuate the plasma surface treatment instrument, then fill it with 20mL of oxygen, the input voltage is 220V, the working distance is 12mm, the plasma flame scanning rate is 100mm / s, and then the surface treatment is performed for 30min to obtain surface-modified nanoporous silicon oxide;

[0044] S2. Preparation of Nanocube Fulvic Acid Humus:

[0045] Weigh 20g lignite, 4g sodium hydroxide, and 800g deionized water, mix them evenly, and oscillate them in a constant temperature oscillator for 8h, the temperature of the constant temperature oscillator is 30°C, and the oscillation rate is 200r / min, then centrifuge to separate the supernatant, add 10% hydrochloric acid solution dropwise to the supernatant until the pH is 1, let it stand for 6h, filter it with a polyethersulfone aqueous phase filter membrane with a pore size of 0.2μm to obtain a secondary supernatant, weigh 50g of the secondary supernatant, add 0.5g thioacetic acid, and place it in a hydrothermal reactor for low-temperature hydrothermal reaction at 100°C for 4h, and then place it in an oven at 40°C for 24h to obtain nano-cube fulvic acid humus, and repeat the hydrothermal process of the secondary supernatant until it is consumed;

[0046] S3. Preparation of saline-alkali soil remediation materials:

[0047] Weigh 1 g of the surface-modified nanoporous silica obtained in step S1, 0.4 g of the nanocubic fulvic acid humus obtained in step S2, and 20 g of deionized water, mix them evenly, and stir them in a water bath at 30 degrees Celsius until dry to obtain a saline-alkali soil remediation material.

[0048] Embodiment three:

[0049] S1. Preparation of nanoporous silica:

[0050] Weigh 10.670g of butyl orthosilicate, 1.067g of 2-aminoethanesulfinic acid, 320.100g of ethanol, and 106.700g of deionized water, mix them evenly, then place them in a hydrothermal reactor for hydrothermal reaction at 160°C for 6h, filter them after the reaction, place them in an oven for drying at 100°C for 6h, and then place them in a muffle furnace for high-temperature roasting at 500°C for 4h to obtain nanoporous silicon oxide particles, then take 1mL of nanoporous silicon oxide particles and place them in a plasma surface treatment instrument, first evacuate the plasma surface treatment instrument, then fill it with 40mL of oxygen, the input voltage is 220V, the working distance is 5mm, the plasma flame scanning rate is 20mm / s, and then the surface treatment is performed for 30min to obtain surface-modified nanoporous silicon oxide;

[0051] S2. Preparation of Nanocube Fulvic Acid Humus:

[0052] Weigh 20g lignite, 10g potassium hydroxide, and 1200g deionized water, mix them evenly, and oscillate them in a constant temperature oscillator for 12h, the temperature of the constant temperature oscillator is 40°C, and the oscillation rate is 300r / min, then centrifuge to separate the supernatant, add a 15% hydrochloric acid solution dropwise to the supernatant until the pH is 2, let it stand for 12h, filter it with a polyethersulfone aqueous phase filter membrane with a pore size of 0.45μm to obtain a secondary supernatant, weigh 50g of the secondary supernatant, add 2.5g thioacetic acid, and place it in a hydrothermal reactor for low-temperature hydrothermal reaction at 110°C for 2h, and then place it in an oven at 60°C for 12h to obtain nano-cube fulvic acid humus, and repeat the hydrothermal process of the secondary supernatant until it is consumed;

[0053] S3. Preparation of soil remediation materials:

[0054] Weigh 1 g of the surface-modified nanoporous silica prepared in step S1, 0.6 g of the nanocubic fulvic acid humus prepared in step S2, and 30 g of deionized water, mix them evenly, and stir them in a water bath at 30 degrees Celsius until dry to obtain a saline-alkali soil remediation material.

[0055] Working principle: The present application is a preparation method and application of a fulvic acid humus saline-alkali soil repair material. The repair material uses nano-cube fulvic acid humus as the repair component, and the repair component is extracted and prepared from lignite, which can not only realize the high-value-added resource utilization of lignite, but also make full use of humus to improve the soil aggregate structure, promote the accumulation of organic matter, and improve the soil moisture retention capacity. Conventional fulvic acid humus has a high impurity content and an amorphous structure. By adopting a hydrothermal method to prepare nano-cubes, the purity of fulvic acid humus is effectively improved, and the effect of the repair material is guaranteed; in addition, the present invention uses 2-aminoethyl During the hydrothermal reaction, alkanesulfinic acid converts silicon salt into nanoporous silica carrier, which can effectively promote the adsorption of humus by the carrier; finally, a plasma surface treatment instrument is used to modify the surface of the nanoporous silica carrier to increase its surface hydroxyl concentration, which can not only enhance the bonding strength between silica and fulvic acid humus during the preparation of the repair material, and ensure that the repair material releases fulvic acid humus for a long time during use, but also use its porous and hydroxyl-rich characteristics to absorb alkali metal ions such as sodium and potassium in the soil after the fulvic acid humus is released, reduce salt accumulation on the soil surface, and promote the rational distribution of water during irrigation.

[0056] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a fulvic acid humus saline-alkali soil remediation material, characterized in that: The invention comprises nanoporous silicon oxide and nano cubic fulvic acid humus, wherein the nanoporous silicon oxide is used as a carrier and the nano cubic fulvic acid humus is used as a repair component, and the nanoporous silicon oxide is used as a carrier and the nano cubic fulvic acid humus is used as a repair component, and the nanoporous silicon oxide carrier is used as a carrier and the repair component is used as a repair component, and the repair component is prepared by a hydrothermal impregnation method; the repair component is prepared by a hydrothermal impregnation method ... S1. Preparation of nanoporous silicon oxide, weighing silicon salt, carrier morphology control agent, ethanol and deionized water, mixing them evenly, and then placing them in a hydrothermal reactor for hydrothermal reaction, filtering and drying after the reaction, and then calcining at high temperature to obtain nanoporous silicon oxide particles, and then placing the nanoporous silicon oxide particles in a plasma surface treatment instrument, first evacuating the plasma surface treatment instrument, then filling it with oxygen, and then performing surface treatment to obtain surface-modified nanoporous silicon oxide; S2. Preparation of nano-cube fulvic acid humus, weigh lignite, extractant and deionized water, mix them evenly and oscillate them on a constant temperature oscillator, then centrifuge to separate the supernatant, add hydrochloric acid to the supernatant until the pH is 1 to 2, let it stand and filter it with a polyethersulfone aqueous phase filter membrane to obtain a secondary supernatant, add a repair component morphology control agent to the secondary supernatant and place it in a hydrothermal reactor for low-temperature hydrothermal reaction, and dry it after completion to obtain nano-cube fulvic acid humus; S3. Preparation of saline-alkali soil remediation materials: weigh the surface-modified nanoporous silica prepared in step S1 and the nanocubic fulvic acid humus prepared in step S2, mix them evenly with deionized water, and stir them in a water bath until dry to obtain saline-alkali soil remediation materials.

2. The method for preparing a fulvic acid humus saline-alkali soil repair material according to claim 1, characterized in that: The silicon salt in step S1 is tetraethyl orthosilicate or butyl orthosilicate, and the carrier morphology control agent is 2-aminoethanesulfinic acid.

3. The method for preparing a fulvic acid humus saline-alkali soil repair material according to claim 1, characterized in that: In the step S1, the mass ratio of silicon salt, carrier morphology control agent, ethanol and deionized water is 1:0.05-0.10:30-60:5-10.

4. The method for preparing a fulvic acid humus saline-alkali soil repair material according to claim 1, characterized in that: In the step S1, the temperature of the hydrothermal reaction is 140 to 160 degrees Celsius, the time of the hydrothermal reaction is 6 to 12 hours, the temperature of the drying is 80 to 100 degrees Celsius, the time of the drying is 6 to 12 hours, the temperature of the high-temperature calcination is 500 to 600 degrees Celsius, and the time of the high-temperature calcination is 2 to 4 hours.

5. The method for preparing a fulvic acid humus saline-alkali soil repair material according to claim 1, characterized in that: The plasma surface treatment instrument in step S1 is a Plasma clean-PL-5010 model. During the surface treatment, the input voltage is 220V, the working distance is 5 to 12mm, and the plasma flame scanning rate is 20 to 100mm / s.

6. The method for preparing a fulvic acid humus saline-alkali soil repair material according to claim 1, characterized in that: In step S1, the volume ratio of oxygen to nanoporous oxide particles is 1:20-40.

7. The method for preparing a fulvic acid humus saline-alkali soil repair material according to claim 1, characterized in that: The extractant in step S2 is sodium hydroxide or potassium hydroxide, the mass ratio of lignite, extractant and deionized water is 1:0.2-0.5:40-60, the hydrochloric acid is a hydrochloric acid solution with a mass fraction of 10% to 15%, the repair component morphology controller in step S2 is thioacetic acid, the mass ratio of the secondary supernatant and the repair component morphology controller is 1:0.01-0.05, the temperature of the low-temperature hydrothermal reaction is 100 to 110 degrees Celsius, the time of the low-temperature hydrothermal reaction is 2 to 4 hours, the drying temperature is 40 to 60 degrees Celsius, and the drying time is 12 to 24 hours.

8. The method for preparing a fulvic acid humus saline-alkali soil repair material according to claim 1, characterized in that: The temperature of the constant temperature oscillator in step S2 is 30 to 40 degrees Celsius, the oscillation time is 8 to 12 hours, the oscillation rate is 200 to 300 r / min, the standing time is 6 to 12 hours, and the pore size of the polyethersulfone aqueous phase filter membrane is 0.2 to 0.45 μm.

9. The method for preparing a fulvic acid humus saline-alkali soil repair material according to claim 1, characterized in that: The mass ratio of the surface-modified nanoporous silica to deionized water in step S3 is 1:20-30, and the stirring temperature in the water bath is 30 to 40 degrees Celsius.

10. The preparation method of a fulvic acid humus saline-alkali soil remediation material according to claims 1 to 9 is applied in the field of soil remediation, and the soil remediation specifically refers to the remediation of saline-alkali soil.

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