Method for repairing chromium-containing pollutants by using aspergillus tubingensis

Abstract

The invention provides a method for repairing chromium-containing pollutants by utilizing aspergillus tubingensis, and belongs to the technical field of repairing heavy metal pollution by utilizing a biotechnology. The method comprises the following steps: extracting and separating extracellular polymeric substances and fungus thalli from a fungus aspergillus tubingensis culture solution to serve as repair materials, adding chromium-containing pollutants, adsorbing hexavalent chromium ions and converting the hexavalent chromium ions into trivalent chromium ions within 60 hours under a normal temperature condition, and filtering out suspended matters to finish the repair of the chromium-containing pollutants. According to the method, the remediation of the chromium-containing pollutants in a relatively wide concentration range can be realized, and the remediation time is not more than 60 hours. Wherein the soluble extracellular polymeric substance is rich in various fungal metabolites including quinones, the repair process can be accelerated by promoting electron transfer, and the pH value does not need to be adjusted in practical application.

Description

TECHNICAL FIELD

[0001] The application relates to a method for repairing chromium-containing pollutants by using Aspergillus tubigensis, and belongs to the field of repairing heavy metal pollution by using biotechnology. BACKGROUND

[0002] Chromium (Cr) is widely used in industrial production, such as leather tanning, electroplating, metal smelting and the like, and a large amount of chromium-containing wastewater (mainly hexavalent chromium ions, Cr (VI)) is generated. At the same time, several typical chromium-containing waste residues such as stainless steel / special steel slag, red mud and chromium-iron alloy slag also contain hexavalent chromium ions. As a primary carcinogen, Cr (VI) has significant multiple toxicity to the nervous system, skin, kidneys and liver of the human body, and even large-dose exposure can cause death.

[0003] Compared with the physical and chemical methods for repairing chromium pollution, the microbial repair technology has the advantages of small disturbance to the original environment, low cost and no secondary pollution. A variety of microorganisms that can tolerate and repair chromium pollution have evolved in nature, which can convert the highly toxic and highly mobile Cr (VI) into low toxicity, low mobility and more stable Cr (III) through adsorption, reduction and precipitation mechanisms. At present, domestic and foreign research has reported a large number of bacteria with Cr (VI) repair capacity, such as Pseudomonas, Bacillus, Serratia and Shewanella. However, the reported species of fungi with chromium repair capacity are mainly Aspergillus and Penicillium.

[0004] The ability of bacteria and fungi to repair Cr (VI) depends largely on their cell structure and metabolic characteristics. Extracellular polymeric substances (EPS) as a highly hydrated matrix wrapped around the periphery of microbial cells play a crucial role in heavy metal repair. In addition, fungal biomass as a waste biomass has great potential in repairing heavy metal pollution. Compared with bacteria, fungi generally show stronger metal tolerance and can synthesize more complex EPS with more functional groups. However, the reports on the sequestration and reduction of Cr (VI) by fungi and their source EPS, especially soluble components (S-EPS), are very limited, and the specific mechanism and key active components are not explored. This leads to the following limitations when directly using live bacteria for wastewater repair: (1) Limited by the threshold of heavy metal inhibition toxicity: there is an upper limit of Cr(VI) tolerance for living bacteria. When the concentration of chromium in wastewater exceeds this threshold, the bacteria will be poisoned, resulting in the complete failure of the repair system. This makes the living bacteria method unstable in the treatment of industrial wastewater with high concentration and large fluctuations.

[0005] (2) Strict environmental conditions: the growth and metabolism of bacteria require suitable pH, temperature, nutrition and avoidance of interference of other toxic substances. The complexity and variability of industrial wastewater often make it difficult to meet these conditions, resulting in limited repair efficiency of bacteria.

[0006] (3) Repair speed depends on metabolism: the reduction of Cr(VI) by living bacteria, especially efficient reduction, often depends on its specific metabolic enzyme (such as chromate reductase). This process requires energy and time, and the repair speed is limited by the growth cycle and metabolic activity of the bacteria. SUMMARY

[0007] Therefore, the application provides a method for removing chromium pollution by Aspergillus tubigensis, which realizes rapid and efficient removal of Cr(VI) ions.

[0008] Specifically, the application is realized by the following scheme: A method for repairing chromium-containing pollutants using Aspergillus tubigensis, using at least one of Aspergillus tubigensis extracellular polymer and fungal cells as repair material, taking chromium-containing wastewater or chromium-containing waste residue as chromium-containing pollutants, adding repair material to chromium-containing pollutants, under normal temperature conditions, within 60 h (preferably 24-60 h), Cr(VI) ions are adsorbed and converted to Cr(III) ions, suspended solids are filtered out, and the repair of chromium-containing wastewater is completed.

[0009] Further, the fungal cells are prepared according to the following steps: after Aspergillus tubigensis is incubated in liquid medium for 60 h, the culture solution is filtered out using medium-speed filter paper, and the obtained precipitate is the fungal cells.

[0010] Further, the Aspergillus tubigensis extracellular polymer is prepared according to the following steps: Step 1), after Aspergillus tubigensis is incubated in liquid medium for 60 h, S-EPS solution is obtained by filtering with medium-speed filter paper and 0.22 μm filter membrane. S-EPS contains quinone substances, which can be used as an electron mediator to promote electron transfer and accelerate the repair process, so it can be used as a repair material alone.

[0011] Step 2), the mycelium is washed with ultrapure water for three times, and dried in a 60 ℃ oven until the weight is constant. The mycelium and ultrapure water are added into a centrifugal bottle, the added mass of ultrapure water is 300 times of the dry weight of the mycelium, and centrifugation is carried out at a relative centrifugal force of 5000 g (unit "g" refers to the relative centrifugal force (RCF), which represents the acceleration experienced by the sample during centrifugation) and 4 ℃ for 30 min. Then, filtration is carried out in sequence using a medium-speed filter paper and a 0.22 μm filter membrane to obtain an LB-EPS solution.

[0012] Step 3), the mycelium after extracting LB-EPS and 0.02 mol / L EDTA·2Na solution are uniformly mixed at a mass ratio of 1:300, and extraction is carried out in a constant-temperature water bath at 70 ℃ and 250 rpm for 30 min. Then, centrifugation is carried out at 5000 g and 4 ℃ for 30 min, and filtration is carried out using a medium-speed filter paper and a 0.22 μm filter membrane to obtain a TB-EPS solution. EDTA·2Na solution are uniformly mixed at a mass ratio of 1:300, and extraction is carried out in a constant-temperature water bath at 70 ℃ and 250 rpm for 30 min. Then, centrifugation is carried out at 5000 g and 4 ℃ for 30 min, and filtration is carried out using a medium-speed filter paper and a 0.22 μm filter membrane to obtain a TB-EPS solution.

[0013] The components of the liquid medium include: 25.0 g / L sucrose, 1.0 g / L potassium dihydrogen phosphate, 0.5 g / L magnesium sulfate, and 1.0 g / L yeast powder.

[0014] The normal temperature refers to 15-35 ℃, and preferably 25-35 ℃.

[0015] When the Aspergillus tubigensis extracellular polymer is used alone as a repair material, the concentration of hexavalent chromium ions in chromium-containing wastewater is 0-2000 mg / L, and the concentration of hexavalent chromium ions in chromium-containing waste residue is 0-300 mg / kg; when the fungal mycelium is used alone as a repair material, the concentration of hexavalent chromium ions in chromium-containing wastewater is 0-300 mg / L; when the Aspergillus tubigensis extracellular polymer and the mycelium are used in combination as a repair material, the concentration of hexavalent chromium ions in chromium-containing wastewater is 0-2000 mg / L, and the concentration of hexavalent chromium ions in chromium-containing waste residue is 0-300 mg / kg.

[0016] More preferably, When the Aspergillus tubigensis extracellular polymer is used alone to repair chromium-containing wastewater, the duration is 0-48 h (and 0 is not taken), and when it is used alone to repair chromium-containing waste residue, the duration is 0-72 h; when the fungal mycelium is used alone to repair chromium-containing wastewater, the duration is 0-72 h (and 0 is not taken); when the extracellular polymer and the fungal mycelium are used in combination to repair chromium-containing wastewater, the duration is 0-48 h (and 0 is not taken), and when they are used in combination to repair chromium-containing waste residue, the duration is 0-72 h (and 0 is not taken).

[0017] When the fungal mycelium is used alone for repair, the initial concentration of hexavalent chromium ions in chromium-containing wastewater is 10-300 mg / L, and the fungal mycelium dosage is 0-20 g / L (and 0 is not taken).

[0018] The Aspergillus tubigensis extracellular polymer is repaired alone, and the Aspergillus tubigensis extracellular polymer includes soluble EPS (S-EPS), loosely bound EPS (LB-EPS) and / or tightly bound EPS (TB-EPS), the initial concentration of the hexavalent chromium ion in the chromium-containing wastewater is 100-2000 mg / L, the concentration of the soluble EPS is 0-625 mg / L (and not 0), the concentration of the loosely bound EPS is 0-200 mg / L, and the concentration of the tightly bound EPS is 0-450 mg / L.

[0019] The Aspergillus tubigensis extracellular polymer and the bacterial body are combined as the repair material, and the extraction and separation step can be omitted.

[0020] The beneficial effects of the present application mainly include but are not limited to the following points: 1) The chromium-containing wastewater and other chromium-containing pollutants have the characteristics of high toxicity, easy diffusion, complex treatment process and high comprehensive cost, and the traditional treatment method often faces problems such as limited efficiency, high cost or easy secondary pollution. In the repair material used in the present application, the soluble EPS produced by the fungus Aspergillus tubigensis shows excellent removal capacity for Cr (VI), and can quickly achieve complete removal of 100 mg / L Cr (VI) in 4 hours. In addition, the Aspergillus tubigensis fungus can create and maintain an ideal acidic environment for removing Cr (VI), which saves the cost and step of additional and regulated acid-base reagents in industrial application. Under this natural condition, the maximum chromium removal amount per unit mass of soluble EPS reaches 1484.31 mg / g, which shows great application potential in the green, efficient and low-cost treatment of chromium-containing wastewater, chromium-containing waste residue and other chromium-containing pollutants.

[0021] 2) The soluble EPS of the present application has the characteristics of biodegradability, non-toxicity and economy. On the one hand, the soluble EPS acts as a natural protective barrier against Cr (VI) toxicity, and on the other hand, the polysaccharides, proteins, quinones and other components contained therein efficiently reduce Cr (VI) through adsorption, electron transfer and reduction mechanisms, and play an important role in the repair of chromium-containing wastewater, chromium-containing waste residue and other chromium-containing pollutants.

[0022] 3) The Aspergillus tubigensis bacterial body of the present application can complete the repair of chromium-containing wastewater, chromium-containing waste residue through adsorption and reduction mechanisms, realize the resource utilization of waste, and achieve the purpose of "waste treatment with waste". In addition, the bacterial body material has good stability and is easy to separate from liquid, and will not cause secondary pollution. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a preparation flowchart of the extracellular polymer in the present application.

[0024] Figure 2The removal rate of 100 mg / L Cr(VI) wastewater by the method of the present application.

[0025] Figure 3 The removal rate of different Cr(VI) concentration wastewater by soluble EPS.

[0026] Figure 4 The removal rate of different Cr(VI) concentration wastewater by Aspergillus tubingensis.

[0027] Figure 5 The change of residual Cr(VI) concentration when removing different concentration of chromium-containing wastewater in Example 4.

[0028] Figure 6 The column chart of the effect of removing chromium-containing waste residue in Example 5.

[0029] Fungus Aspergillus tubingensis: classified as Aspergillus tubingensis, Latin name Aspergillus tubingensis, deposited in China General Microbiological Culture Collection Center (CGMCC) on January 18, 2013, and the preservation number is CGMCC NO. 7174. DETAILED DESCRIPTION

[0030] In order to make the person skilled in the art better understand the technical solutions in the present application, in the following examples, the chromium-containing wastewater is prepared by using potassium dichromate (K2Cr2O7), and the chromium-containing waste residue is taken from the red mud in a certain place in Guangxi.

[0031] The fungus Aspergillus tubingensis is isolated from local farmland. The strain is cultured according to the following method: the spore liquid of the fungus Aspergillus tubingensis is inoculated into a sterile potato dextrose agar (PDA) slant tube for subculture, then the spores on the surface of the slant tube are eluted with sterile 0.5% Tween 80 solution, and then inoculated into a liquid culture medium, and incubated in a constant temperature shaker at 30°C and 150 rpm for 60 h. The composition of the liquid culture medium is: 25.0 g / L sucrose, 1.0 g / L potassium dihydrogen phosphate, 0.5 g / L magnesium sulfate, and 1.0 g / L yeast powder, which is sterilized at 121°C for 20 min.

[0032] Strain morphological description and identification content: the strain grows rapidly on the culture medium, the colony is flat, with radial wrinkles, the texture is velvet, the conidia are brown and black, the edge has white mycelium, and the colony reverse is yellow-brown. Conidial head is spherical, diameter is 150-450 μm, conidiophore occurs in substrate, wall is smooth, top cyst is spherical or nearly spherical, sporulation structure is double layer, conidium is spherical or nearly spherical, diameter is 3-4 μm, wall is slightly rough. The rDNA-ITS sequence alignment shows that the strain has the highest homology with Aspergillus tubingensis (HQ315841.1) in Aspergillus, the ITS sequence similarity reaches 100%, and the strain is identified as Aspergillus tubingensis F12 (Aspergillus tubingensis F12).

[0033] In combination Figure 1 , the extracellular polymers of Aspergillus tubingensis and fungal mycelium are prepared as follows: Step 1), after the Aspergillus tubingensis is incubated in the liquid medium for 60 h, the culture solution is filtered out using medium-speed filter paper, and the obtained precipitate is the fungal mycelium. The culture solution is further filtered through a 0.22 μm filter membrane to obtain a solution as an S-EPS solution.

[0034] Step 2), the fungal mycelium is washed with ultrapure water for three times, and is dried to constant weight in a 60 ℃ oven. The mycelium and ultrapure water are added into a centrifugal bottle, the added mass of the ultrapure water is 300 times of the dry weight of the mycelium, and the mixture is centrifuged at a centrifugal force of 5000 g and a temperature of 4 ℃ for 30 min. The mixture is filtered through medium-speed filter paper and a 0.22 μm filter membrane in sequence to obtain an LB-EPS solution.

[0035] Step 3), the mycelium after extraction of the LB-EPS and 0.02 mol·L -1 EDTA·2Na solution are uniformly mixed at a mass ratio of 1:300, and are extracted in a constant-temperature water bath at 70 ℃ and 250 rpm for 30 min. The mixture is centrifuged at a centrifugal force of 5000 g and a temperature of 4 ℃ for 30 min, and is filtered through medium-speed filter paper and a 0.22 μm filter membrane to obtain a TB-EPS solution.

[0036] The calculation formula involved in the examples is as follows: 1) Cr(VI) removal rate R (%): The content of Cr(VI) in the wastewater is determined by the diphenyl carbazide spectrophotometric method (GB / T 5750.6-2023). The removal rate calculation formula is: , In the formula, C 0 and C tThe values ​​represent the initial and residual concentrations of Cr(VI) in the wastewater, respectively, in mg / L.

[0037] 2) EPS adsorption capacity q e The formula for calculating (mg / g) is: ; In the formula, C 0 and Ce The values ​​represent the initial concentration of Cr(VI) in the wastewater and the residual concentration of Cr(VI) at equilibrium, respectively, in mg / L. V The volume of wastewater used is expressed in liters (L). m The value represents the mass of EPS, expressed in grams (g).

[0038] Example 1 This embodiment uses different EPS as remediation materials to remediate chromium-containing wastewater: Different EPS components were added to chromium-containing wastewater, and the pH values ​​of loosely bound EPS and tightly bound EPS were adjusted to match those of soluble EPS (pH = 2.7 ± 0.1) using 0.1 mol / L H₂SO₄ or NaOH solution. The concentrations of Cr(VI) in the chromium-containing wastewater were: 100 mg / L; 625 mg / L for soluble EPS; 200 mg / L for loosely bound EPS; and 450 mg / L for tightly bound EPS. The reaction was carried out in a constant-temperature shaker at 30°C and 150 rpm for 24 h.

[0039] Depend on Figure 2 It can be seen that soluble EPS (S-EPS) achieved a 100% removal rate of Cr(VI) from wastewater, while the removal rates of tightly bound EPS (TB-EPS) and loosely bound EPS (LB-EPS) were 22.19% and 3.39%, respectively. This result indicates that soluble EPS has excellent potential for chromium pollution remediation.

[0040] Example 2 This embodiment uses soluble EPS as the remediation material to remediate chromium-containing wastewater with different Cr(VI) concentrations: Soluble EPS was added to chromium-containing wastewater. The concentration of Cr(VI) in the chromium-containing wastewater was 100–2000 mg / L (represented by 100, 400, 800, 1200, 1600, and 2000 mg / L); the concentration of soluble EPS was 625 mg / L, and the mixture was reacted in a constant temperature shaker at 30°C and 150 rpm for 24 h.

[0041] Depend on Figure 3It can be seen that S-EPS exhibits extremely high Cr(VI) removal activity: it achieves complete removal of 100 mg / L Cr(VI) within 4 hours, and the removal rate reaches as high as 99.91% when the concentration is increased to 400 mg / L. Even under high concentration conditions of 800 mg / L and 1200 mg / L, its Cr(VI) removal rate still reaches 92.66% and 64.88%, respectively. For chromium-containing wastewater under saturation (Cr(VI) concentration of 1600 mg / L), the maximum chromium removal per unit mass of soluble EPS reaches 1484.31 mg / g.

[0042] Example 3 This embodiment uses fungal cells as a remediation material for the remediation of chromium-containing wastewater: Aspergillus tabineus cells were added to chromium-containing wastewater. The dosage was 5 g / L (i.e., 5 g of fungal cells were added per liter of chromium-containing wastewater), and the Cr(VI) concentration in the wastewater was 10–300 mg / L (represented by 10, 25, 50, 100, 200, and 300 mg / L). The pH of the wastewater was adjusted to 2.7 ± 0.1 using 0.1 mol / L H₂SO₄ or NaOH solution, and the reaction was carried out for 60 h in a constant temperature shaker at 30°C and 150 rpm.

[0043] Depend on Figure 4 It can be seen that when the Cr(VI) concentration in chromium-containing wastewater is not higher than 25 mg / L, fungal cells can completely remove Cr(VI). When the Cr(VI) concentration is 50, 100, 200 and 300 mg / L, the removal rates are 89.68%, 76.65%, 71.49% and 45.82%, respectively.

[0044] Example 4 This embodiment uses a combination of extracellular polymeric substances (EPS) and fungal cells as remediation materials. The extracellular polymeric substances include soluble EPS, loosely bound EPS, and tightly bound EPS. The concentration of soluble EPS is 625 mg / L, the concentration of loosely bound EPS is 200 mg / L, and the concentration of tightly bound EPS is 450 mg / L. The fungal cell content is 3.4 g (dry weight) / L. This method is used for the remediation of chromium-containing wastewater. After incubating Aspergillus tabine in liquid culture medium for 60 h, a culture medium containing extracellular polymers and fungal cells was obtained. This culture was then added to chromium-containing wastewater and reacted in a constant temperature shaker at 30°C and 150 rpm for 24 h.

[0045] Depend on Figure 5It can be seen that the Cr(VI) in the concentration group of 50-500 mg / L is rapidly removed within the first 4 h, among which the 50 mg / L and 100 mg / L Cr(VI) are completely removed at 0.25 h and 0.5 h respectively, and the final residual concentrations of 200, 300, 500 mg / L Cr(VI) are only 0.094, 0.18, 0.44 mg / L respectively, all of which are lower than the limit value (0.5 mg / L) of the industrial wastewater discharge standard in China.

[0046] Example 5 In this example, the extracellular polymers and fungal cells are combined as the repair material, the extracellular polymers include soluble EPS, loosely bound EPS and tightly bound EPS, the concentration of soluble EPS is 625 mg / L, the concentration of loosely bound EPS is 200 mg / L, the concentration of tightly bound EPS is 450 mg / L, and the content of fungal cells is 3.4 g (dry weight) / L, and the chromium-containing waste residue, i.e. red mud, is repaired. After the Aspergillus tubigensis is incubated in the liquid medium for 60 h, the culture solution containing extracellular polymers and fungal cells is obtained and added to 5 g of red mud as the experimental group, wherein the initial content of Cr(VI) in the red mud is 202.22 mg / kg. At the same time, an equal volume of fresh liquid medium is used instead of the culture solution as the control group. The control group and the experimental group are respectively reacted in a constant temperature shaker at 30°C and 150 rpm for 24 h, and after the reaction is completed, the residual Cr(VI) content in the solid phase and the liquid phase is measured.

[0047] The results are shown in Table 1. Figure 6 The Cr(VI) content in the red mud of the control group decreases from the initial 202.22 mg / kg to 31.90 mg / kg, and the removal rate is 83.18%; the Cr(VI) content in the red mud of the experimental group decreases from the initial 202.22 mg / kg to 12.20 mg / kg, which is lower than the risk control value (30.00 mg / kg) of the first type of land in the "Risk Control Standard for Construction Land Soil Pollution", and the removal rate increases to 92.92%.

[0048] Based on the residual Cr(VI) content, i.e. adding the culture solution containing extracellular polymers and fungal cells to the control group, the Cr(VI) content in the red mud decreases from 31.90 mg / kg to 12.20 mg / kg, and the fungal biological contribution further reduces the Cr(VI) content in the red mud by 61.76% based on the control group. This result clearly shows that the Aspergillus tubigensis has a significant biological enhancement effect on the removal of Cr(VI) in the red mud.

[0049] ​In addition, the concentration of Cr(VI) in the supernatant of the experimental group and the control group was maintained at a low level of about 2.11 mg / L without significant difference, which proved that the fungal bioremediation process did not cause a large amount of dissolution of Cr(VI), and the environmental risk of the remediation process was low.

Claims

1. A method for remediating chromium-containing contaminants using Aspergillus tabineus, characterized in that: Using at least one of the following as a remediation materials: Aspergillus tabinea extracellular polymeric polymer and fungal cells, and chromium-containing wastewater or chromium-containing waste residue as chromium-containing pollutants, the remediation material is added to the chromium-containing pollutants. Under normal temperature conditions, hexavalent chromium ions are adsorbed and converted into trivalent chromium ions within 60 hours, and suspended solids are filtered out, thus completing the remediation of chromium-containing pollutants.

2. The method for remediation of chromium-containing pollutants using Aspergillus tabineum according to claim 1, characterized in that, The extracellular polymeric material of Aspergillus tabineus includes soluble EPS, which is prepared by incubating Aspergillus tabineus in a liquid culture medium for 60 hours, using medium-speed filter paper to obtain a precipitate of fungal cells, and then filtering with a 0.22 μm filter membrane to obtain a soluble EPS solution.

3. A method for remediating chromium-containing contaminants using Aspergillus tabineum according to claim 2, characterized in that: This also includes loosely bound EPS and / or tightly bound EPS. The filtered bacterial cells were washed three times with ultrapure water and dried in a 60 ℃ oven to constant weight. The mycelium and ultrapure water were added to a centrifuge bottle, with the ultrapure water added at 300 times the dry weight of the mycelium. The mixture was centrifuged for 30 min at a relative centrifugal force of 5000 g and 4 ℃. The solution was then filtered sequentially using medium-speed filter paper and a 0.22 μm filter membrane to obtain a loosely bound EPS solution. The bacterial cells and 0.02 mol·L⁻¹ of the loosely bound EPS were then extracted. -1 The EDTA·2Na solution was mixed at a mass ratio of 1:300 and extracted in a constant temperature water bath at 70 ℃ and 250 rpm for 30 min. The mixture was then centrifuged at 5000 g and 4 ℃ for 30 min and filtered using medium-speed filter paper and a 0.22 μm filter membrane to obtain a tightly bound EPS solution.

4. A method for remediating chromium-containing contaminants using Aspergillus tabineum according to claim 2, characterized in that, The components of the liquid culture medium are: 25.0 g / L sucrose, 1.0 g / L potassium dihydrogen phosphate, 0.5 g / L magnesium sulfate, 1.0 g / L yeast extract.

5. A method for remediating chromium-containing contaminants using Aspergillus tabineum according to claim 1, characterized in that: The ambient temperature refers to 15–35 °C.

6. A method for remediating chromium-containing contaminants using Aspergillus tabineum according to any one of claims 1 to 5, characterized in that: The remediation material is an extracellular polymeric substance of Aspergillus tabineus, corresponding to a hexavalent chromium ion concentration of 0–2000 mg / L in the chromium-containing wastewater and a hexavalent chromium ion concentration of 0–300 mg / kg in the chromium-containing waste residue; or, the remediation material is fungal cells, corresponding to a hexavalent chromium ion concentration of 0–300 mg / L in the chromium-containing wastewater; or, the remediation material is a combination of Aspergillus tabineus extracellular polymeric substance and fungal cells, corresponding to a hexavalent chromium ion concentration of 0–2000 mg / L in the chromium-containing wastewater and a hexavalent chromium ion concentration of 0–300 mg / kg in the chromium-containing waste residue.

7. A method for remediating chromium-containing contaminants using Aspergillus tabineum according to claim 6, characterized in that: The chromium-containing pollutant is chromium-containing wastewater. The remediation time is 0–48 h when using Aspergillus tabinea extracellular polymeric polymer alone as the remediation material, 0–72 h when using fungal cells alone as the remediation material, and 0–48 h when using Aspergillus tabinea extracellular polymeric polymer and fungal cells in combination as the remediation material.

8. A method for remediating chromium-containing contaminants using Aspergillus tabineum according to claim 6, characterized in that: The chromium-containing pollutant is chromium-containing waste residue. The remediation time is 0-72 hours when using Aspergillus tabinea extracellular polymeric material alone as the remediation material, and 0-72 hours when using Aspergillus tabinea extracellular polymeric material and fungal cells in combination as the remediation material.

9. A method for remediating chromium-containing contaminants using Aspergillus tabineum according to claim 1, characterized in that: The extracellular polymeric substances of Aspergillus tabineus include soluble EPS, loosely bound EPS, and tightly bound EPS; the chromium-containing pollutant is chromium-containing wastewater, wherein the initial concentration of hexavalent chromium ions in the chromium-containing wastewater is 100–2000 mg / L, the concentration of soluble EPS is 0–625 mg / L and not zero, the concentration of loosely bound EPS is 0–200 mg / L, and the concentration of tightly bound EPS is 0–450 mg / L.

10. A method for remediating chromium-containing contaminants using Aspergillus tabineum according to claim 1, characterized in that: The remediation material is fungal cells, the chromium-containing pollutant is chromium-containing wastewater, the initial concentration of hexavalent chromium ions in the chromium-containing wastewater is 10-300 mg / L, and the dosage of fungal cells relative to the chromium-containing wastewater is 0-20 g / L, and is not taken as 0.

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