Denitrification fiber cotton and its preparation method and application

Abstract

The present invention belongs to the field of ecological restoration materials, and specifically relates to a denitrification fiber cotton, its preparation method, and application. The method comprises: uniformly mixing basalt and dolomite, melting, and drawing to obtain stone fibers; roasting coconut shells to obtain coconut shell biochar; adding the stone fibers and coconut shell biochar to a surface impregnant, stirring, washing, and drying to obtain a C@ stone fiber block; adding the C@ stone fiber block to a potassium permanganate solution, stirring, filtering, washing, and drying to obtain the denitrification fiber cotton. The denitrification fiber cotton achieves an adsorption and catalytic effect on ammonia nitrogen in water while maintaining high water storage and water retention properties of the fiber cotton, and has excellent environmental compatibility. When used in the process of sponge city construction, it can achieve functions such as ecological water storage, soil and water conservation, ammonia nitrogen degradation, and water purification.

Description

Technical Field

[0001] The present invention belongs to the field of ecological restoration materials, and in particular relates to denitrification fiber cotton and a preparation method and application thereof. Background Art

[0002] Non-point source pollution is caused by pollutants emitted from various activities and processes, including industry, transportation, construction, and agriculture. Rainfall is a major factor contributing to non-point source pollution. Rainfall carries pollutants into water bodies or seeps into the soil, causing water pollution and exacerbating soil erosion and water loss. Ammonia nitrogen is a common non-point source pollutant, primarily originating from agricultural breeding, fertilizer use, and wastewater discharge. Rainfall washes ammonia nitrogen from livestock and poultry manure and urine into surface waters, causing excessive ammonia nitrogen levels in the water. Furthermore, rainfall causes nitrogen from applied fertilizers to be lost into water bodies. Excessive ammonia nitrogen causes eutrophication of water bodies and disrupts the aquatic ecological balance. Therefore, controlling excessive ammonia nitrogen levels is crucial for water environmental protection and human health.

[0003] Porous fiber cotton is an ecological, green, and environmentally friendly product that can improve soil and has broad application prospects in rainwater storage and infiltration. However, porous fiber cotton still faces problems in practical applications. First, long-term exposure to humid environments makes it susceptible to corrosion by microorganisms, acids, alkalis, and other factors, reducing durability and service life. Second, long-term operation may cause changes in structural properties, which will be affected by water load and temperature changes, affecting the long-term stability of rainwater storage and infiltration performance. In addition, the ecological effect of ecological fiber cotton is single, and further exploration is needed to improve environmental compatibility and water purification. Solving these problems requires improving materials and preparation processes, selecting corrosion-resistant materials, taking anti-corrosion measures to improve durability, and optimizing structural design and preparation processes to improve long-term stability and performance consistency. In summary, porous fiber cotton has broad prospects in rainwater storage and infiltration, but problems such as durability, structural stability, and ecological effects need to be urgently addressed.

[0004] Currently, there are existing technologies for producing basalt fiber. For example, the patented technology "A Basalt Fiber and Its Preparation Method" (CN110078378B) discloses a method for producing basalt fiber using basalt, waste talc, dark nickel serpentine, and alumina as raw materials, melting them at high temperatures in a resistance furnace or electric arc furnace, and spinning them into a yarn. However, the quartz in the talc used in this method is harmful to the human body, and the resulting basalt fiber poses a safety risk. The patented technology "A Basalt Fiber Preparation Method" (CN109956675B) discloses a method for producing basalt fiber by adding zircon sand to basalt ore and mixing them evenly. However, domestic zircon sand reserves are scarce, and the huge supply gap requires reliance on foreign imports, resulting in a continuous increase in prices. The patented technology "A Method for Ecological Restoration of Black and Smelly Rivers" (CN110330120A) discloses a technology for ecologically restoring bottom mud using inorganic mineral materials and bacterial mud powder. However, the two materials act independently, making them difficult to use and time-consuming and labor-intensive to lay.

[0005] Given the current problem of "sponge bodies" only filtering and removing SS after water storage, with insufficient purification capacity for eutrophication indicators and even increased levels of key pollution indicators during the release process, research on sponge materials with high water retention and permeability, as well as adsorption and biopurification capabilities, is of great significance. Biochar, with its strong toughness and high corrosion resistance, can be loaded onto fiber cotton to improve its environmental compatibility. Simultaneously, biochar modified with potassium permanganate and loaded with manganese dioxide on its surface enhances the mechanical properties of the mineral wool while providing surface active sites, catalyzing pollutants such as ammonia and nitrogen in the body.

[0006] In view of this, it is of great significance to develop and utilize the composite of mineral wool and biochar in order to prepare fiber cotton with high water absorption, high water storage, high efficiency denitrification and water pollution repair functions. Summary of the Invention

[0007] To address the shortcomings of existing ecological restoration and water storage materials, the present invention provides a denitrification fiber cotton, its preparation method, and its application. Using dolomite and basalt as a composite carrier, biochar fibers and a manganese-based metal catalytic material are coated on the fiber cotton surface via a surface impregnant. The materials are then mixed, bonded to a matrix, and sintered at high temperature to create a novel sponge material. This material exhibits high water absorption, high water storage, efficient denitrification, and the ability to remediate water pollution.

[0008] To achieve the above object, the present invention is implemented through the following technical solutions:

[0009] The present invention provides a method for preparing denitrified fiber cotton, comprising the following steps:

[0010] Step 1: Mix basalt and dolomite evenly, melt them, and draw them into fibers to obtain stone fibers;

[0011] Step 2: roasting the coconut shell to obtain coconut shell biochar;

[0012] Step 3: Add the stone fiber and coconut shell biochar to the surface impregnant, stir, wash, and dry to obtain a C@stone fiber block;

[0013] Step 4: adding the C@ stone fiber block to the potassium permanganate solution, stirring, filtering, washing, and drying to obtain the denitrification fiber cotton.

[0014] Furthermore, in step 1, the basalt includes the following components in mass percentage: Al2O3: 14% to 19%, CaO: 5% to 9%, MgO: 3% to 6%, Fe2O3+FeO: 9% to 14%, TiO2: 0.5% to 2.5%, Na2O+K2O: 3% to 8%, and the remainder is SiO2 and unavoidable impurities; the dolomite includes the following components in mass percentage: SiO2≤2.0%, CaO≥29.0%, MgO≥20%, and loss on ignition≤40%.

[0015] Furthermore, in step 1, the mass ratio of basalt to dolomite is (75-95):(5-25).

[0016] Furthermore, in step 1, the melting temperature is 1450-1500°C, and the wire drawing temperature is 1290-1350°C.

[0017] Furthermore, in step 2, the calcination temperature is 800-850°C.

[0018] Furthermore, in step 3, the mass ratio of stone fiber to coconut shell biochar is 1:(1-2.5).

[0019] Furthermore, in step 3, the surface wetting agent is at least one of epoxy emulsion, lipid compound, 3-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane and 3-(methacryloyloxy)propyltrimethoxysilane.

[0020] Furthermore, in step 4, the molar concentration of the potassium permanganate solution is 0.1 to 1 mol / L.

[0021] The present invention also provides denitrified fiber cotton prepared by the above-mentioned preparation method.

[0022] The present invention also provides the use of the denitrifying fiber cotton produced by the aforementioned preparation method in ecological restoration. The denitrifying fiber cotton of the present invention achieves adsorption and catalysis of ammonia nitrogen in water while maintaining its high water storage and retention properties, exhibiting excellent environmental compatibility. Its use in sponge city construction can achieve functions such as ecological water storage, soil and water conservation, ammonia nitrogen degradation, and water purification.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The main materials of the ecological fiber cotton prepared by the present invention are all derived from low-cost minerals and biomass carbon, and have the characteristics of being green, low-carbon and economical.

[0025] (2) During the preparation of fiber wool, the loading of biochar enhances the corrosion resistance of natural mineral wool, improves its toughness and tolerance, and is conducive to maintaining the original properties and structure in the ecological process.

[0026] (3) The introduction of fiber cotton biochar can also introduce manganese dioxide catalyst by reacting with potassium permanganate, and ammonia nitrogen is adsorbed on the active sites with catalytic oxidation function by electrostatic adsorption, and the effect of removing ammonia nitrogen is achieved through redox reaction.

[0027] (4) Using low-cost inorganic fiber cotton for ecological restoration can not only store rainwater (regulate water volume), regulate runoff rainfall, and prevent soil erosion, but also purify water quality and remove COD, SS, ammonia nitrogen, etc.

[0028] (5) The fiber cotton prepared by the present invention has a wide range of applications and can be used not only for ecological restoration of natural water bodies, but also for purification and restoration of black and odorous water bodies and reclaimed water. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A front view of the porous fiber cotton prepared according to the present invention;

[0030] Figure 2 This is a diagram showing the effect of porous fiber cotton in Example 3 of the present invention in removing ammonia nitrogen from water. DETAILED DESCRIPTION

[0031] To facilitate understanding of the present invention, the present invention will be described more fully below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0032] The basalt used in the following embodiments includes the following components in mass percentage: Al2O3: 14% to 19%, CaO: 5% to 9%, MgO: 3% to 6%, Fe2O3 + FeO: 9% to 14%, TiO2: 0.5% to 2.5%, Na2O + K2O: 3% to 8%, and the remainder is SiO2 and unavoidable impurities; the dolomite includes the following components in mass percentage: SiO2≤2.0%, CaO≥29.0%, MgO≥20%, and loss on ignition≤40%.

[0033] Example 1

[0034] First, 75wt% basalt and 25% dolomite are mixed evenly as raw materials to obtain a mixture; the mixture is then placed in a resistance furnace to melt at 1450℃, and spun at 1350℃ to obtain stone fiber; the coconut shell is crushed and placed in a tubular furnace, and heated at 800℃ in a nitrogen atmosphere to obtain coconut shell biochar; the stone fiber and biochar are then added to 3-aminopropyltriethoxysilane in a mass ratio of 1:1, stirred at 400r / min for 6h, and then dried to constant weight to obtain C@stone fiber block; the C@stone fiber block is then added to 0.1mol / L potassium permanganate solution at a ratio of 1:2.5 (g / ml), stirred at a rate of 400r / min for 12h until the supernatant is colorless, and finally rinsed with distilled water several times until neutral, and then dried at a constant temperature of 105℃ to constant weight to obtain high-efficiency denitrification fiber cotton.

[0035] Example 2

[0036] First, 80wt% basalt and 20wt% dolomite are mixed evenly as raw materials to obtain a mixture; the mixture is then placed in a resistance furnace to melt at 1450℃, and spun at 1300℃ to obtain stone fiber; the coconut shell is crushed and placed in a tubular furnace, and heated at 850℃ in a nitrogen atmosphere to obtain coconut shell biochar; the stone fiber and biochar are then added to 3-aminopropyltriethoxysilane in a mass ratio of 1:1.5, stirred at 400r / min for 6h, and then dried to constant weight to obtain C@stone fiber block; the C@stone fiber block is then added to 0.25mol / L potassium permanganate solution in a ratio of 1:2.5 (g / ml), stirred at a rate of 400r / min for 12h until the supernatant is colorless, and finally rinsed with distilled water several times until neutral, and then dried at a constant temperature of 105℃ to constant weight to obtain high-efficiency denitrification fiber cotton.

[0037] Example 3

[0038] First, 80wt% basalt and 20wt% dolomite are mixed evenly as raw materials to obtain a mixture; the mixture is then placed in a resistance furnace to melt at 1450℃, and spun at 1350℃ to obtain stone fiber; the coconut shell is crushed and placed in a tubular furnace, and heated at 850℃ in a nitrogen atmosphere to obtain coconut shell biochar; the stone fiber and biochar are then added to 3-aminopropyltriethoxysilane in a mass ratio of 1:2, stirred at 400r / min for 6h, and then dried to constant weight to obtain C@stone fiber block; the C@stone fiber block is then added to 0.5mol / L potassium permanganate solution in a ratio of 1:2.5 (g / ml), stirred at a rate of 400r / min for 12h until the supernatant is colorless, and finally rinsed with distilled water several times until neutral, and then dried at a constant temperature of 105℃ to constant weight to obtain high-efficiency denitrification fiber cotton.

[0039] Example 4

[0040] First, 80wt% basalt and 20wt% dolomite are mixed uniformly as raw materials to obtain a mixture; the mixture is then placed in a resistance furnace to melt at 1450℃ and spun at 1350℃ to obtain stone fiber; coconut shells are then crushed and placed in a tubular furnace and heated at 850℃ in a nitrogen atmosphere to obtain coconut shell biochar; stone fiber and biochar are then added to 3-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:2, the temperature is raised to 50℃, and the stirring speed is 150r / min. After stirring for 15 minutes, the speed was adjusted to 250 r / min and stirred for 20 minutes. After stopping stirring, it was cooled to room temperature, washed with water 3 times, and naturally air-dried to obtain C@ stone fiber blocks; then the C@ stone fiber blocks were added to 1 mol / L potassium permanganate solution at a ratio of 1:2.5 (g / ml), stirred at a rate of 400 r / min for 12 hours until the supernatant was colorless, and finally rinsed with distilled water several times until neutral and then dried at a constant temperature of 105°C to constant weight to obtain high-efficiency denitrification fiber cotton.

[0041] Example 5

[0042] First, 80wt% of basalt and 20wt% of dolomite are mixed evenly as raw materials to obtain a mixture; the mixture is then placed in a resistance furnace to melt at 1450°C, and spun at 1350°C to obtain stone fiber; coconut shell is crushed and placed in a tubular furnace, and heated at 850°C in a nitrogen atmosphere to obtain coconut shell biomass char; γ-glycidyloxypropyltrimethoxysilane is ultrasonically dispersed in anhydrous ethanol to obtain an anhydrous ethanol solution of γ-glycidyloxypropyltrimethoxysilane, and the above-mentioned coconut shell biomass char is added, stirred at 100°C for 3h, repeatedly filtered with anhydrous ethanol several times, and finally dried at 100°C to constant weight; the stone fiber and biomass char are then mixed. Carbon was added to 3-(methacryloyloxy)propyltrimethoxysilane in a mass ratio of 1:2, the temperature was raised to 50°C, and the stirrer was stirred at a speed of 150 r / min for 15 minutes. The speed was adjusted to 250 r / min and stirred for 20 minutes. After the stirring stopped, it was cooled to room temperature, washed with water 3 times, and naturally air-dried to obtain C@stone fiber blocks; then the C@stone fiber blocks were added to 1 mol / L potassium permanganate solution in a ratio of 1:2.5 (g / ml), stirred at a rate of 400 r / min for 12 hours until the supernatant was colorless, and finally rinsed with distilled water several times until neutral and then dried at a constant temperature of 105°C to constant weight to obtain high-efficiency denitrification fiber cotton.

[0043] The C loading measurement results of the high-efficiency denitrification fiber cotton prepared in Examples 1 to 5 are shown in Table 1.

[0044] The high-efficiency denitrification fiber cotton prepared in Example 1 was tested: at 40kn / m 2 Under load, the water storage efficiency per unit volume reaches 88%, the COD removal rate is greater than 56%, and the SS removal rate is greater than 77%.

[0045] The high-efficiency denitrification fiber cotton prepared in Example 2 was tested: at 40kn / m 2 Under load, the water storage efficiency per unit volume reaches 94%, the COD removal rate is greater than 65%, and the SS removal rate is greater than 85%.

[0046] The high-efficiency denitrification fiber cotton prepared in Examples 1 to 5 above was used to treat eutrophic water with an ammonia nitrogen concentration of 7 mg / L. After 12 hours of adsorption and catalysis, the degradation rate was measured and the results are shown in Table 1.

[0047] Table 1 C loading and ammonia nitrogen degradation rate of high-efficiency denitrification fiber cotton prepared in Examples 1 to 5

[0048] Example 1 Example 2 Example 3 Example 4 Example 5 C loading / % 43 48 61 66 83 Ammonia nitrogen degradation rate / % 42 45 72 79 85

[0049] The above description is only for better explanation of the embodiments of the present invention and is not intended to limit the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention are intended to be within the scope of the present invention.

Claims

1. A method for preparing denitrified fiber cotton, characterized in that: The following steps are involved: Step 1: Mix basalt and dolomite evenly, melt them, and draw them into fibers to obtain stone fibers; Step 2: roasting the coconut shell to obtain coconut shell biochar; Step 3: Add the stone fiber and coconut shell biochar to the surface impregnant, stir, wash, and dry to obtain a C@stone fiber block; Step 4: adding the C@ stone fiber block to the potassium permanganate solution, stirring, filtering, washing, and drying to obtain the denitrification fiber cotton.

2. The method for preparing denitrification fiber cotton according to claim 1, characterized in that: In step 1, the basalt includes the following components in mass percentage: Al2O3: 14% to 19%, CaO: 5% to 9%, MgO: 3% to 6%, Fe2O3+FeO: 9% to 14%, TiO2: 0.5% to 2.5%, Na2O+K2O: 3% to 8%, and the remainder is SiO2 and unavoidable impurities; the dolomite includes the following components in mass percentage: SiO2≤2.0%, CaO≥29.0%, MgO≥20%, and loss on ignition≤40%.

3. The method for preparing denitrification fiber cotton according to claim 1, characterized in that: In step 1, the mass ratio of basalt to dolomite is (75-95):(5-25).

4. The method for preparing denitrification fiber cotton according to claim 1, characterized in that: In step 1, the melting temperature is 1450-1500°C, and the wire drawing temperature is 1290-1350°C.

5. The method for preparing denitrification fiber cotton according to claim 1, characterized in that: In the step 2, the calcination temperature is 800-850°C.

6. The method for preparing denitrification fiber cotton according to claim 1, characterized in that: In step 3, the mass ratio of stone fiber to coconut shell biochar is 1:(1-2.5).

7. The method for preparing denitrified fiber cotton according to claim 1, characterized in that: In step 3, the surface wetting agent is at least one of epoxy emulsion, lipid compound, 3-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane and 3-(methacryloyloxy)propyltrimethoxysilane.

8. The method for preparing denitrification fiber cotton according to claim 1, characterized in that: In step 4, the molar concentration of the potassium permanganate solution is 0.1 to 1 mol / L.

9. Denitrified fiber cotton produced by the preparation method according to any one of claims 1 to 8.

10. Use of the denitrification fiber cotton prepared by the preparation method according to any one of claims 1 to 8 in ecological restoration.

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