CN113818152B - A kind of preparation method and application of biochar nanofiber membrane loaded with microorganisms - Google Patents

Abstract

The invention discloses a method for preparing a microorganism-loaded biomass carbon nanofiber membrane and its application. The nanofiber membrane prepared by electrospinning and added with straw biomass charcoal is soaked in a method inoculated with Hershanmonas arsenica After being cultured at 27-29°C to the logarithmic growth phase in the liquid medium, and then incubated for 9-11h, the arsenic-oxidizing bacteria in the culture medium can fully adhere to the biochar nanofiber membrane. The biochar nanofiber membrane loaded with microorganisms is obtained. The biomass carbon nanofiber membrane loaded with microorganisms prepared by the present invention shows good As(III) biocatalytic effect and recycling performance in five cyclic reaction cycles, and is a good microorganism carrier, and with As the number of cycles increased, the catalytic efficiency of the microbial composite membrane for As(III) oxidation gradually increased.

Description

A kind of preparation method and application of biochar nanofiber membrane loaded with microorganisms

technical field

The invention belongs to the technical field of microbial composite materials, and in particular relates to a preparation method and application of a microbial-loaded biomass carbon nanofiber membrane.

Background technique

With the continuous growth of the world's population and the advancement of urban industrialization, water resources are being polluted more and more seriously, and a large amount of arsenic-containing wastewater is discharged into the environment. Arsenic (As) is a first-class carcinogen that is toxic to the human body and other organisms. It can enter the human body through the respiratory tract and skin, and quickly distributes to the whole body through the blood. Most of it will combine with lipoproteins of hemoglobin, causing skin, Reproductive, cancer, neurological and cardiovascular diseases. Arsenic in the environment mainly exists in two soluble forms, AsO ₂ ^- (trivalent) and AsO ₄ ^3- (pentavalent), among which As(III) is 60-100 times more toxic than As(V), and As(III) is more mobile and water-soluble.

The removal of arsenic from wastewater is a worldwide environmental problem, and the existing arsenic removal technologies reported in the prior art can be summarized into the following main categories: oxidation, precipitation, coagulation, membrane separation, ion exchange, biological treatment systems, and adsorption. In some cases, these arsenic removal technologies can be used in combination to maximize the removal of arsenic compounds from environmental systems. Among them, natural minerals, metal oxide nanoparticles, graphene oxide, and carbon-based composite materials have been widely used in the adsorption and removal of arsenic in wastewater due to their high specific surface area and good adsorption capacity. However, since As(III) is not easily removed by negatively charged adsorbents, it is usually necessary to pre-oxidize As(III) to As(V). However, the oxidation rate of As(III) to As(V) by oxygen is very slow, and chemical oxidants are often expensive and may produce secondary pollutants. Therefore, As(III) oxidation by arsenic-oxidizing bacteria is considered to be a cheaper and environmentally friendly option. It has been found that some bacteria such as Bacillus, Proteus, Pseudomonas, Rhizobium and Micrococcus have a certain ability to oxidize and fix As(III).

However, in the actual application process, microorganisms are difficult to enrich and recycle, and may cause secondary biological pollution to the environment, which limits their use in the treatment of environmental problems. Therefore, loading microorganisms into a fixed form of carrier medium or forming a certain thickness of biofilm on the matrix material to achieve scientific recycling has become a hot spot in current research. CN 113248004 A discloses a method for preparing microbial carriers for sewage treatment, in which microorganisms are embedded in prepared polyvinyl alcohol resin pellets, and a series of modification treatments are performed to apply to sewage treatment. The preparation process is simple and the cost is low , but has the disadvantages of low porosity, poor mass transfer, and entrapment leading to a decrease in microbial activity. CN 112897705 A discloses a preparation method and application of a multilayer graphene oxide modified microbial carrier, using a silane coupling agent to modify the surface function of the polyurethane carrier, and grafting multilayer graphene oxide on the surface of the carrier, thereby Improve the bio-loading capacity of the carrier, the preparation method is low in cost, the thermal stability of the modified carrier is strong, and it can solve the problem of long film-hanging time in the bio-immobilization process, but there are also complex processes, low porosity, and difficult materials. Disadvantages of recycling.

Contents of the invention

The purpose of the present invention is to overcome the defects of the prior art and provide a method for preparing a microorganism-loaded biomass carbon nanofiber membrane.

Another object of the present invention is to provide the application of the above-mentioned biomass carbon nanofiber membrane loaded with microorganisms.

Technical scheme of the present invention is as follows:

A preparation method of a biochar nanofiber membrane loaded with microorganisms, comprising the steps of:

(1) Wash and pulverize the waste biomass straw, pass through a 200-mesh sieve, and then dry;

(2) Slowly add concentrated sulfuric acid to the material obtained in step (1), fully stir and mix, then slowly add hydrogen peroxide under ice bath conditions, stir while adding to prevent liquid splashing, make the material fully carbonized, and use after cooling to room temperature Fully wash with deionized water until nearly neutral, centrifuge to obtain a precipitate, and then dry to obtain straw biochar;

(3) Stir and mix polyacrylonitrile, the above-mentioned straw biomass charcoal, and N,N-dimethylformamide at 55-65° C., and then undergo ultrasonic treatment to obtain a spinning solution;

(4) Electrospinning the above-mentioned spinning solution to obtain a nanofiber membrane;

(5) heating the above nanofiber membrane to 260-280°C for half-carbonization for 1.5-2.5 hours while maintaining an appropriate tension to obtain a precursor product;

(6) After the above-mentioned precursor product is lowered to room temperature, it is cut into shape, and heated to 790-810°C for 1.5-2.5 hours under a nitrogen atmosphere;

(7) Activate the material obtained in step (6) with a KOH solution at room temperature for 10-12h, then wash with deionized water until neutral, and then dry to obtain a biomass carbon nanofiber membrane;

(8) Soak the above-mentioned biochar nanofiber membrane in the liquid medium inoculated with Hershanmonas arsenic oxidans, cultivate it to the logarithmic growth phase at 27-29°C, and then incubate for 9-11h to make the culture The Hershanmonas arsenoxidans in the solution is fully adhered to the biomass carbon nanofiber membrane, and thus the microorganism-loaded biomass carbon nanofiber membrane is obtained.

In a preferred embodiment of the present invention, in the step (2), the ratio of the material obtained in the step (1), concentrated sulfuric acid and hydrogen peroxide is 28-31g: 190-210mL: 60-70mL.

Further preferably, in the step (2), the drying temperature is 77-81° C. and the drying time is 45-50 h.

In a preferred embodiment of the present invention, in the step (3), the concentration of the N,N-dimethylformamide is 98%, and the Mr of the polyacrylonitrile is 150,000.

Further preferably, the ratio of the polyacrylonitrile, the straw biomass charcoal and N,N-dimethylformamide is 0.2-0.6g:2.0g:20mL.

Even more preferably, the ratio of the polyacrylonitrile, the straw biomass charcoal and N,N-dimethylformamide is 0.4g:2.0g:20mL.

In a preferred embodiment of the present invention, the specific process of the electrospinning in the step (4) is: slowly suck the spinning solution into a 20mL syringe, the metal needle type is No. 20, and the inner diameter is 0.6mm; The distance between the syringe and the receiving roller is 16cm, the injection speed is 0.1mm/min, and the receiving roller rotates at 100rpm; a positive voltage of 17kV is applied to the needle tip, and a negative voltage of 3kV is applied to the receiving roller for electrospinning; electrospinning The time is set to 12 hours, and the temperature and humidity in the electrospinning equipment box are kept at 35°C and 40% respectively; after spinning, the film is gently peeled off and placed in a vacuum oven, and dried at 60°C for 12 hours to remove surface residues solvent.

In a preferred embodiment of the present invention, the preparation method of the liquid culture medium in described step (8) comprises:

A. Prepare the following three solutions:

Solution A: 81.2 mM MgSO ₄ 7H ₂ O, 187 mM NH ₄ Cl, 70 mM Na ₂ SO ₄ , 0.574 mM K ₂ HPO ₄ , 4.57 mM CaCl ₂ 2H ₂ O, 446 mM Na Lactate,

Solution B: 4.8 mM FeSO ₄ ·7H ₂ O,

Solution C: 950 mM NaHCO ₃ ;

B. Sterilize solution A at 121°C for 20 minutes, and filter solutions B and C through a filter with a pore size of 0.22 μm.

C. Prepare the liquid medium according to the following ratio: mix 100mL solution A, 2.5mL solution B, and 10mL solution C, make up to 1L with water, and adjust its pH to 7.2 to obtain the liquid medium.

Another technical solution of the present invention is as follows:

Application of the microbial carbon nanofiber membrane loaded with microorganisms prepared by the above preparation method in the removal of As(III) in environmental water.

A method for removing As(III) in environmental water bodies, comprising using the microbial-loaded biomass carbon nanofiber membrane prepared by the above-mentioned preparation method.

The beneficial effects of the present invention are:

1. The biochar nanofiber membrane of the present invention has good comprehensive mechanical properties, has a certain degree of flexibility, and is suitable for use in sewage treatment systems, and because it uses waste biomass straws as raw materials, it reduces production costs and reduces the cost of chemicals. The use realizes the purpose of environmental friendliness and "treating waste with waste".

2. The present invention adds biochar to electrospun carbon nanofibers, and uses KOH to carry out surface activation modification, so that the composite membrane material obtained has a large specific surface area, high roughness and more micropores, and due to The added biochar is prepared by chemical oxidation, which endows the composite membrane with good hydrophilicity and biocompatibility, provides sufficient space for the enrichment and growth of microorganisms, and also provides a large number of active sites for attachment.

3. The biomass carbon nanofiber membrane loaded with microorganisms prepared by the present invention shows good As(III) biocatalytic effect and recycling performance in five cyclic reaction cycles, and is a good microorganism carrier, and As the number of cycles increased, the catalytic efficiency of the microbial composite membrane for As(III) oxidation gradually increased.

Description of drawings

Fig. 1 is a schematic diagram of the preparation process of the biomass carbon nanofiber membrane loaded with microorganisms in Example 1 of the present invention.

Fig. 2 is a comparison diagram of scanning electron microscope and transmission electron microscope of biomass charcoal nanofiber membranes with different amounts of straw biochar added in Example 2 of the present invention.

Fig. 3 is a comparison chart of stress-strain curves and Young's modulus curves of biochar nanofiber membranes with different amounts of straw biochar added in Example 3 of the present invention.

Fig. 4 is a comparison chart of Fourier transform infrared spectra before and after loading microorganisms on biomass carbon nanofiber membranes with different amounts of straw biochar added in Example 4 of the present invention.

Fig. 5 is a graph showing the comparison of the amount of microorganisms attached to the biochar nanofiber membrane loaded with microorganisms with different amounts of straw biochar added in Example 5 of the present invention.

Fig. 6 is a comparison chart of cycle performance test results of microbial-loaded biochar nanofiber membranes with different amounts of straw biochar added in Example 6 of the present invention.

detailed description

The technical solutions of the present invention will be further illustrated and described below through specific embodiments in conjunction with the accompanying drawings.

The straw used in the present invention was purchased from Beijing Soleibao Technology Co., Ltd. Other drugs used in the present invention were purchased from Sigma Aldrich (Shanghai) Trading Co., Ltd. The microorganism Hershanmonas arsenicoxydans (ULPAs1, DSM 17148) used in the present invention was purchased from DSMZ-German Microorganism and Cell Culture Co., Ltd., German Microorganism Culture Collection.

Example 1

As shown in Figure 1, a kind of preparation method of the biomass carbon nanofiber membrane of loaded microorganism, comprises the steps:

(1) Use waste biomass straw as raw material, wash and crush it, pass it through a 200-mesh sieve and dry it at 80°C;

(2) Slowly add 200mL of concentrated sulfuric acid to the material obtained in 30g of step (1) and stir for 20-30min, then slowly add 67mL of hydrogen peroxide under ice bath conditions according to the volume ratio of concentrated sulfuric acid and hydrogen peroxide as 3:1, and stir while adding, Prevent the liquid from splashing and fully carbonize the straw. After cooling down to room temperature, add deionized water to wash several times. When the washing solution is close to neutral, centrifuge and separate the precipitate, and dry at 80°C for 48 hours to obtain straw biochar;

(3) Add straw biochar (0g, 0.2g, 0.4g and 0.6g) and 2.0g polyacrylonitrile (Mr=150,000) into 20mL of N,N-dimethylformamide (98%), at 60 ℃ magnetic stirring in a water bath for 10 hours, and finally ultrasonic for 2 hours to obtain spinning solution;

(4) Electrospinning the above spinning solution to obtain nanofiber membrane, specifically: slowly inhale the spinning solution into a 20 mL syringe with a metal needle of No. 20 (inner diameter 0.6 mm). Set the distance between the syringe and the receiving roller to be 16 cm, the injection speed to be 0.1 mm/min, and the rotating speed of the receiving roller to be 100 rpm. Electrospinning was performed by applying a positive voltage of 17 kV to the needle tip and a negative voltage of 3 kV to the receiving roll. To ensure that the thickness of the nanofiber film obtained on the receiving roll was similar each time, the electrospinning time was set to 12 h. In addition, the temperature and humidity in the box of the electrospinning equipment (Beijing Yongkang Leye Technology Development Co., Ltd., SS-1334H) were kept at about 35°C and 40%, respectively. After spinning, the film is gently peeled off and placed in a vacuum oven, and dried at 60°C for 12 hours to remove residual solvent on the surface;

(5) Fix the four corners of the above-mentioned nanofiber membrane into the muffle furnace to maintain a certain tension, and raise the temperature from room temperature to 260°C at a rate of 1°C/min in an air atmosphere and keep it for 2h for semi-carbonization (pre-oxidation) to obtain precursor products;

(6) After the above precursor product was lowered to room temperature, it was carefully cut into a rectangle of ₈ cm × 1.5 cm, put into a porcelain boat and placed in a tube furnace, and the temperature was increased from room temperature to Rise to 800°C and keep for 2h for carbonization;

(7) After cooling the material obtained in step (6) to room temperature, immerse it in a 2M/L KOH solution to activate it for 12 hours, then take it out and wash it with deionized water until neutral, then dry it at 60°C for 6 hours to obtain biochar Nanofiber membrane (corresponding to the amount of straw biochar added, followed by BACF-0, BACF-0.2, BACF-0.4, BACF-0.6);

(8) The above-mentioned biomass carbon nanofiber membrane is soaked in the liquid culture medium inoculated with Hershanomonas arsenic oxidizers to prepare the biomass carbon nanofiber membrane loaded with microorganisms, the steps are as follows:

I. Herminiimonas arsenicoxydans (ULPAs1, DSM 17148) was purchased from DSMZ-German Microorganism and Cell Culture Co., Ltd.

II. Prepare a chemically defined liquid medium by mixing the following three solutions: Solution A: 81.2mM MgSO ₄ 7H ₂ O (Sigma), 187mM NH ₄ Cl (Merck, 99.8%), 70mM Na ₂ SO ₄ (Prolabo , 99%), 0.574 mM K ₂ HPO ₄ (Prolabo, 97%), 4.57 mM CaCl ₂ ·2H ₂ O (Merck, 99.5%), 446 mM sodium lactate (Sigma, 98%). Solution B: 4.8 mM FeSO ₄ ·7H ₂ O (Prolabo, 99%). Solution C: 950 mM NaHCO ₃ (Prolabo, 99.5%). Solution A was sterilized by high temperature and high pressure (121° C., 20 min), and solutions B and C were sterilized by filtration through a filter with a pore size of 0.22 μm. Then mix 100 mL of solution A, 2.5 mL of solution B, and 10 mL of solution C, make up to 1 L with water, and adjust its pH to 7.2 to obtain a liquid medium. All solutions were prepared with deionized water previously sterilized by autoclaving.

III. Take the bacteria liquid in the ultra-clean bench and add it to 50mL sterilized liquid medium to mix evenly, then put in two pieces of 8cm×1.5cm biomass activated carbon nanofiber membranes, put them into 28°C, shake at 100rpm Cultivate in bed. When it reached the logarithmic phase of growth, it was transferred to an incubator at 28°C to continue culturing for 10 hours, so that as many bacteria in the culture solution as possible could settle and adhere to the surface of the composite membrane. The final biochar nanofiber membrane loaded with microorganisms is obtained after taking out.

Example 2

The biochar nanofiber membranes prepared in Example 1 with different additions of straw biochar were observed by scanning electron microscope and transmission electron microscope.

Scanning electron microscope sample preparation: The sample is glued on the sample observation table of the scanning electron microscope with conductive glue, and then the sample is sprayed with platinum for 30 seconds, and then vacuumed at a voltage of 15kV to observe the microscopic morphology of the sample.

Transmission electron microscope sample preparation: Take a small amount of sample powder and dissolve it in alcohol. After ultrasonicating the sample solution for 2 hours, take a small amount and drop it on the pretreated copper grid with a rubber dropper. After the alcohol evaporates and dries, store the sample copper grid in Store in a desiccator.

The results are shown in Figure 2. The surface and interior of the activated nanofibers have more pores, the specific surface area of the material increases, and there is a certain degree of flexibility. With the increase of the amount of straw biochar, the roughness of the nanofibers increases. When the amount of addition reaches 0.4g, the surface modification is the most uniform, in the shape of a string of beads, and continuous addition will lead to fiber bonding and thicker diameter.

Example 3

Biomass carbon nanofiber membranes with different amounts of straw biochar added by the method of Example 1 were used as experimental samples, which were placed under the mold and pressed into a barbell shape of 3 × 10mm (as shown in Figure 3b) with a model machine. Tensile strain machine for testing. Before the test, use a vernier caliper to measure the thickness of the sample and input it into the test method of the system, then fix the sample to be tested in the clamping hole of the tensile strain machine, adjust the position of the sensor, and reset the stress and displacement to zero. rate stretched sample. As shown in Figure 3a, with the increase of straw biochar content, the tensile strain at break of the composite film increases and the tensile strength at break decreases; the Young's modulus of the material calculated by the formula decreases gradually (as shown in Figure 3b), which is expressed as The rigidity of the material is reduced and the flexibility is enhanced; from the tensile strain at break and strength of the material, it can be concluded that BACF-0.2 and BACF-0.4 have better comprehensive mechanical properties and are suitable for microbial liquid culture systems.

Example 4

The materials formed by the biochar nanofiber membranes with different amounts of straw biochar added by the method in Example 1 before and after loading microorganisms were used as experimental samples, and were tested by a Fourier transform infrared spectrometer. The samples were all prepared by KBr tableting method. The specific operation was to mix the sample to be tested with spectrally pure KBr at a mass ratio of 1:100, grind and mix in an agate mortar, and then press the tablet to prepare samples. The test is carried out at room temperature, and the wavelength range of the instrument is 4000-500cm ^-1 . As shown in Figure 4, compared with before loading, the surface hydrophilicity and electropositive functional groups (amino groups, aldehyde groups) of each biomass carbon nanofiber membrane after loading appear, which is beneficial to the further adhesion of bacteria; The peak intensity of oxygen functional groups (hydroxyl, carboxyl, etc.) was significantly enhanced, indicating that the oxidation of biochar nanofiber membranes was enhanced.

Example 5

The biochar nanofiber membrane loaded with microorganisms prepared by the method of Example 1 with different amounts of straw biochar added was used as an experimental sample, and the biomass attached to the membrane was determined by the BCA method. As shown in Figure 5, the biomass loaded on the surface of the material showed a trend of first increasing and then decreasing with the increase of straw biochar addition. When the addition of straw biochar was 0.4g, it reached the highest in the experimental group—— 47.43 μg/cm ² .

Example 6

The biochar nanofiber membrane loaded with microorganisms of different straw biochar additions prepared by the method of Example 1 was used as an experimental sample, and after each 72h cycle, the last microbial composite membrane was put into a mixture containing 50mg/L As(III ) fresh medium, repeat the cycle test like this, and detect the concentration of As(III) in the medium by atomic fluorescence spectrometry-liquid chromatography every 12 hours or so. As shown in Figure 6, each microbial composite membrane showed better and better biocatalytic effect in the cycle experiment, and when the addition amount of straw biochar was 0.4g, the catalytic effect on As(III) oxidation was the best; In the five-cycle performance test, due to the thickness of the surface biofilm and the evolution effect of microorganisms on the composite film, it tends to be stable, and it remains stable after reaching its own optimal value.

The above is only a preferred embodiment of the present invention, so the scope of the present invention cannot be limited accordingly, that is, equivalent changes and modifications made according to the patent scope of the present invention and the content of the specification should still be covered by the present invention In the range.

Claims (7)

1. A preparation method of a biomass charcoal nanofiber membrane loaded with microorganisms is characterized by comprising the following steps: the method comprises the following steps:

(1) Cleaning and crushing waste biomass straws, sieving the straws with a 200-mesh sieve, and drying the straws;

(2) Slowly adding concentrated sulfuric acid into the material obtained in the step (1), fully stirring and mixing, then slowly adding hydrogen peroxide under an ice bath condition, stirring while adding to prevent liquid from splashing, fully carbonizing the material, cooling to room temperature, fully washing with deionized water to be nearly neutral, centrifuging to obtain a precipitate, and then drying to obtain straw biomass charcoal; the proportion of the material obtained in the step (1), concentrated sulfuric acid and hydrogen peroxide is 28-31g:190-210mL:60-70mL;

(3) Stirring and mixing polyacrylonitrile, the straw biomass charcoal and N, N-dimethylformamide at 55-65 ℃, and then carrying out ultrasonic treatment to obtain a spinning solution; the concentration of N, N-dimethylformamide is 98%, and the Mr of polyacrylonitrile is 150,000; the ratio of polyacrylonitrile to the straw biomass charcoal to N, N-dimethylformamide is 0.2-0.6g:2.0g:20mL;

(4) Performing electrostatic spinning on the spinning solution to obtain a nanofiber membrane;

(5) Heating the nanofiber membrane to 260-280 ℃ under the condition of keeping proper tension, preserving heat and semi-carbonizing for 1.5-2.5h to obtain a precursor product;

(6) Cooling the precursor product to room temperature, cutting and molding, heating to 790-810 ℃ in nitrogen atmosphere, preserving heat and carbonizing for 1.5-2.5h;

(7) Activating the material obtained in the step (6) by using a KOH solution at room temperature for 10-12h, washing the material to be neutral by using deionized water, and drying the material to obtain a biomass carbon nanofiber membrane;

(8) And soaking the biomass carbon nanofiber membrane in a liquid culture medium inoculated with arsenic-oxidizing Hertzia Hertziae, culturing at 27-29 ℃ until the logarithmic growth phase, and then performing heat preservation culture for 9-11h to ensure that the arsenic-oxidizing Hertzia Hertziae in the culture solution is fully adhered to the biomass carbon nanofiber membrane, thus obtaining the biomass carbon nanofiber membrane loaded with the microorganisms.

2. The method of claim 1, wherein: in the step (2), the drying temperature is 77-81 ℃ and the drying time is 45-50h.

3. The method of claim 1, wherein: the ratio of polyacrylonitrile to the straw biomass charcoal to N, N-dimethylformamide is 0.4g:2.0g:20mL.

4. The method of claim 1, wherein: the specific process of electrostatic spinning in the step (4) is as follows: slowly sucking the spinning solution into a 20mL syringe, wherein the type of a metal needle is 20, and the inner diameter of the metal needle is 0.6mm; setting the distance between the injector and the receiving roller to be 16cm, the injection speed to be 0.1mm/min and the rotating speed of the receiving roller to be 100rpm; applying a positive voltage of 17kV to a needle point, and applying a negative voltage of 3kV to a receiving roller to carry out electrostatic spinning; setting the electrospinning time to be 12h, and keeping the temperature and the humidity in a box body of the electrostatic spinning equipment at 35 ℃ and 40% respectively; and after spinning is finished, slightly removing the film, putting the film into a vacuum oven, and drying the film for 12 hours at the temperature of 60 ℃ to remove residual solvent on the surface.

5. The method of claim 1, wherein: the preparation method of the liquid medium in the step (8) comprises the following steps:

A. the following three solutions were prepared:

solution A:81.2mM MgSO ₄ ·7H ₂ O，187mM NH ₄ Cl，70mM Na ₂ SO ₄ ，0.574mM K ₂ HPO ₄ ，4.57mM CaCl ₂ ·2H ₂ O,446mM sodium lactate,

solution B:4.8mM FeSO ₄ ·7H ₂ O，

Solution C:950mM NaHCO ₃ ；

B. Sterilizing solution A at 121 deg.C for 20min, and filtering solution B and C through 0.22 μm pore size filter for sterilization; c. Preparing a liquid culture medium according to the following proportion: mixing 100mL of the solution A,2.5mL of the solution B and 10mL of the solution C, supplementing the mixture to 1L with water, and adjusting the pH value to 7.2 to obtain the liquid culture medium.

6. Use of the biomass charcoal nanofiber membrane loaded with microorganisms prepared by the preparation method of any one of claims 1 to 5 in removing As (III) in environmental water.

7. A method for removing As (III) from an environmental water body, comprising: comprises the biomass charcoal nanofiber membrane loaded with microorganisms prepared by the preparation method of any one of claims 1 to 5.

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