A sea squirt hot pyrolysis derived adsorptive material, and a preparation method and application thereof

Abstract

The application belongs to the technical field of adsorbing materials, and particularly relates to a sepia cuttle pyrolysis derived adsorbing material and a preparation method and application thereof. The sepia cuttle pyrolysis derived material provided by the application has a calcium carbonate matrix with a porous house frame type pore channel structure and an organic carbon film covering the surface of the calcium carbonate skeleton and the pore channel wall, can realize synchronous removal of heavy metals and eDNA in water, exhibits high removal efficiency on composite pollutants in water, and is more convenient for recycling due to the block structure.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of adsorption materials, and particularly relates to a sepia cuttle pyrolysis derived adsorption material and a preparation method and application thereof. BACKGROUND

[0002] Global water pollution has both natural and anthropogenic sources, such as untreated domestic sewage, mining and land development, industry and solid waste disposal, agricultural runoff, etc. The diversity of emission sources complicates the composition of pollutants in water bodies. In addition to traditional pollutants such as heavy metals and organic dyes, new environmental pollutants are constantly emerging in chemical classification. As a carrier of antibiotic resistance genes (ARGs), environmental DNA (eDNA) has become a new emerging pollutant that has attracted much attention, especially its combination with heavy metal ions, which further enhances the biological toxicity of pollutants. Therefore, for the treatment of sewage, not only the removal technology for each type of pollutant needs to be developed, but also a method capable of simultaneously removing pollutants of different properties needs to be developed for sewage discharge.

[0003] Currently, mature methods such as chemical precipitation, ion exchange, membrane reaction and adsorption are often used for the removal of traditional pollutants such as heavy metals in sewage treatment. There are disinfection, coagulation, advanced oxidation and adsorption technologies for eDNA sewage treatment. The Chinese invention patent entitled "A method for removing antibiotic resistance genes in sewage" (publication number: CN106698652A) has good removal effect on resistance genes in sewage by constructing an anoxic / aerobic-membrane bioreactor, but the operation and management are complex, and the removal effect is greatly affected by water quality components and operating environment. In addition, nanoparticles with high specific surface area have high adsorption efficiency for heavy metals and eDNA, but the cost and environmental risk of nanomaterials are high, which limits their application. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a sepia cuttle pyrolysis derived adsorption material and a preparation method and application thereof. The sepia cuttle pyrolysis derived adsorption material provided by the present application can simultaneously remove heavy metals and eDNA in sewage.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] The present application provides a sepia cuttle pyrolysis derived adsorption material, which comprises a calcium carbonate framework with a porous house frame type pore structure and an organic carbon film covering the surface and pore wall of the calcium carbonate framework; the spacing of the pores is 50-200 μm.

[0007] The mass percentage content of the calcium carbonate skeleton in the sea squirt hot pyrolysis derived adsorption material is 95-97%, and the mass percentage content of the organic carbon film is 3-5%.

[0008] The application also provides a preparation method of the sea squirt hot pyrolysis derived adsorption material in the above scheme, comprising the following steps:

[0009] The sea squirt is sequentially dried and pyrolyzed to obtain the sea squirt hot pyrolysis derived adsorption material.

[0010] Preferably, the pyrolysis temperature is 300-600 DEG C, and the holding time is 1-2 h.

[0011] Preferably, the pyrolysis is carried out under anoxic conditions or limited oxygen conditions; the limited oxygen conditions are that the volume content of oxygen is controlled to be lower than 1%.

[0012] The application also provides an application of the sea squirt hot pyrolysis derived adsorption material in the above scheme or the sea squirt hot pyrolysis derived adsorption material prepared by the preparation method in the above scheme in synchronous removal of heavy metals and eDNA in a water body.

[0013] The application also provides a method for synchronous removal of heavy metals and eDNA in a water body, characterized by comprising the following steps:

[0014] The sea squirt hot pyrolysis derived adsorption material is added into the water body for adsorption treatment;

[0015] The sea squirt hot pyrolysis derived adsorption material is the sea squirt hot pyrolysis derived adsorption material in the above scheme or the sea squirt hot pyrolysis derived adsorption material prepared by the preparation method in the above scheme.

[0016] Preferably, the heavy metal ions in the water body include one or more of Cd 2+ , Mn 2+ , Zn 2+ and Cu 2+ ; and the eDNA in the water body includes one or more of herring sperm DNA, salmon sperm DNA, ampicillin-resistant gene and calf thymus DNA.

[0017] Preferably, the concentration of the heavy metal ions in the water body is 1-60 mg / L; and the concentration of the eDNA in the water body is 1-64 mg / L.

[0018] Preferably, the dosage of the sea squirt hot pyrolysis derived adsorption material is 4.8-50 mg / L.

[0019] Preferably, the adsorption treatment temperature is 2-40 DEG C, and the time is 1-7 d.

[0020] The application provides a sepia hot pyrolysis derived adsorption material, which comprises a calcium carbonate framework with a porous house frame type pore channel structure and an organic carbon film covering the surface of the calcium carbonate framework and the pore channel wall; the interval of the pore channel is 50-200 mu m; the mass percentage content of the calcium carbonate framework in the sepia hot pyrolysis derived adsorption material is 95-97%, and the mass percentage content of the organic carbon film is 3-5%.

[0021] The sepia hot pyrolysis derived material provided by the application has a calcium carbonate matrix with a porous house frame type pore channel structure and an organic carbon film covering the surface of the calcium carbonate framework and the pore channel wall, and the porous framework is beneficial to the diffusion and adsorption of eDNA macromolecules; the framework is composed of calcium carbonate, and the surface of the organic carbon film has rich functional groups, both of which can react with heavy metals to realize the synchronous removal of heavy metals and eDNA in water, and show high removal efficiency for composite pollutants in water, and the blocky structure is more convenient for recycling.

[0022] The application uses the fishery waste of sepia as a raw material to prepare the sepia hot pyrolysis derived material, realizes the resource disposal of the sepia waste, and uses the pyrolysis derivative as an environmental protection and efficient adsorption material to realize water purification and reduce the energy consumption of sewage treatment. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The scanning electron microscope image of the sepia hot pyrolysis derived material prepared in example 1 of the application;

[0024] Figure 2 The Fourier infrared spectrum of the sepia hot pyrolysis derived material prepared in example 1 of the application. DETAILED DESCRIPTION

[0025] The application provides a sepia hot pyrolysis derived adsorption material, which comprises a calcium carbonate framework with a porous house frame type pore channel structure and an organic carbon film covering the surface of the calcium carbonate framework and the pore channel wall; the interval of the pore channel is 50-200 mu m;

[0026] The mass percentage content of the calcium carbonate framework in the sepia hot pyrolysis derived adsorption material is 95-97%, and the mass percentage content of the organic carbon film is 3-5%.

[0027] In the present application, the sea squirt pyrolysis derived adsorption material comprises a calcium carbonate skeleton with a porous house frame type pore structure and an organic carbon film covering the surface of the calcium carbonate skeleton and the pore walls thereof; the spacing of the pores is 50-200 μm, preferably 200 μm; the mass percentage of the calcium carbonate skeleton in the sea squirt pyrolysis derived adsorption material is 95-97%, preferably 95-96%, and the mass percentage of the organic carbon film is 3-5%, preferably 4-5%; the porous house frame type pore structure is composed of a main skeleton and an auxiliary skeleton, the main skeleton is formed by calcium carbonate plates arranged in a horizontal and parallel manner, and the auxiliary skeleton is formed by calcium carbonate partitions vertically filled in the main skeleton to form a house frame type pore.

[0028] In the present application, the specific surface area of the sea squirt pyrolysis derived adsorption material is preferably 4.21 m 2 / g, and the pore volume is preferably 0.03 m 2 / g.

[0029] In the present application, the sea squirt pyrolysis derived adsorption material is preferably in a block shape, and more preferably in a cylindrical block shape; the diameter of the cylindrical block shape is 0.5-1 cm, more preferably 0.5 cm, and the height is 0.5-1 cm, more preferably 0.5 cm.

[0030] The sea squirt pyrolysis derived material provided by the present application has a calcium carbonate matrix with a porous house frame type pore structure and an organic carbon film covering the surface of the calcium carbonate skeleton and the pore walls thereof, and the porous skeleton is beneficial to the diffusion and adsorption of eDNA molecules; the skeleton is composed of calcium carbonate, and the surface of the organic carbon film has a large number of functional groups, both of which can react with heavy metals to realize the synchronous removal of heavy metals and eDNA in water, and exhibit high removal efficiency for complex pollutants in water, and the block structure is more convenient for recycling.

[0031] The present application also provides a preparation method of the sea squirt pyrolysis derived adsorption material described in the above technical solution, which comprises the following steps:

[0032] The sea squirt is sequentially dried and pyrolyzed to obtain the sea squirt pyrolysis derived adsorption material.

[0033] Unless otherwise specified, the present application has no special requirements for the source of the raw materials used for preparation, and commercially available goods known to those skilled in the art can be used.

[0034] Before drying, the sea squirt is preferably washed and formed into a block shape, and more preferably a cylindrical block shape.

[0035] In the present application, the reagent used for washing is preferably water, and more preferably ultrapure water. The washing is not specially limited in the present application, and the sea squirt can be washed clean.

[0036] In the present application, the diameter of the cylindrical block is 0.5-1 cm, more preferably 0.5 cm, and the height is 0.5-1 cm, more preferably 0.5 cm. The present application does not have special limitations on the method for preparing the cylindrical block, and the cylindrical block can be obtained by using a method well known in the art. In the embodiments of the present application, the cuttlebone is cut into a cylindrical block.

[0037] In the present application, the drying temperature is preferably 60-80℃, more preferably 80℃, and the holding time is preferably 1-2h, more preferably 2h; the drying equipment is preferably a vacuum drying oven; the drying is preferably vacuum drying; and the vacuum degree of the vacuum drying is preferably -10 to -20kPa, more preferably -20kPa.

[0038] In the present application, the pyrolysis temperature is preferably 300-600℃, more preferably 500℃, and the holding time is preferably 1-2h, more preferably 2h; the pyrolysis is preferably carried out under oxygen-free conditions or oxygen-limited conditions; the oxygen-limited conditions are preferably controlled to have an oxygen volume content of less than 1%, more preferably 0.5%; and the oxygen-free conditions or oxygen-limited conditions are preferably created by using a protective gas; and the protective gas is preferably nitrogen.

[0039] The present application uses cuttlebone, a fishery waste, as a raw material to prepare cuttlebone pyrolysis derivative materials, which not only realizes the resource disposal of cuttlebone waste, but also makes the pyrolysis derivatives as environmental protection and efficient adsorption materials, which are beneficial to water purification and reduce the energy consumption of sewage treatment.

[0040] The present application also provides the use of the cuttlebone pyrolysis derivative adsorption material in the above technical solution or the cuttlebone pyrolysis derivative adsorption material prepared by the preparation method in the above technical solution in the simultaneous removal of heavy metals and eDNA in water.

[0041] The present application also provides a method for simultaneously removing heavy metals and eDNA in water, characterized in that it comprises the following steps:

[0042] adding the cuttlebone pyrolysis derivative adsorption material to the water for adsorption treatment;

[0043] The cuttlebone pyrolysis derivative adsorption material is the cuttlebone pyrolysis derivative adsorption material in the above technical solution or the cuttlebone pyrolysis derivative adsorption material prepared by the preparation method in the above technical solution.

[0044] In the present application, the heavy metal ions in the water preferably include one or more of Cd 2+ , Mn 2+ , Zn 2+ , and Cu 2+ , more preferably Cd 2+The eDNA in the water body preferably comprises one or more of herring sperm DNA, salmon sperm DNA, ampicillin-resistant gene, and calf thymus DNA, and more preferably herring sperm DNA.

[0045] In the present application, the concentration of heavy metal ions in the water body is preferably 1-60 mg / L, and more preferably 16-60 mg / L; and the concentration of eDNA in the water body is preferably 1-64 mg / L, and more preferably 16-64 mg / L.

[0046] In the present application, the dosage of the cuttlebone pyrolysis-derived adsorption material is preferably 4.8-50 mg / L, and more preferably 5-20 mg / L.

[0047] In the present application, the adsorption treatment is preferably carried out at a temperature of 2-40℃, and more preferably 20-30℃, for 1-7 days, and more preferably 3-6 days.

[0048] After the adsorption treatment, the present application preferably further comprises recycling the cuttlebone pyrolysis-derived adsorption material after being separated from the water body and desorbed.

[0049] In the present application, the desorption is preferably carried out using a phosphate buffer solution; the concentration of the phosphate buffer solution is preferably 0.02-2 mol / L, and more preferably 0.05-2 mol / L; and the recycling is preferably carried out 3-4 times, and more preferably 3 times.

[0050] The present application mixes and reacts the cuttlebone pyrolysis-derived material with the heavy metal / eDNA contaminated water body, and separates the material to achieve the purpose of simultaneously removing the heavy metal and eDNA in the water body; and the cuttlebone pyrolysis-derived material adsorbed with the pollutants is recycled through phosphate desorption-readsorption. The present application realizes the resourceful disposal of fishery waste by using the cuttlebone pyrolysis-derived material, and the cuttlebone pyrolysis-derived material exhibits excellent adsorption effect in the simultaneous removal of heavy metal and eDNA composite pollutants in the water body, and the blocky structure facilitates the recycling of the material.

[0051] The technical solutions of the present application will be described clearly and completely below in combination with the embodiments in the present application, but they should not be understood as limitations to the scope of protection of the present application.

[0052] Example 1

[0053] The intact structure of cuttlefish bone was selected and washed clean with ultrapure water, and then the cleaned cuttlefish bone was cut into a cylindrical block with a diameter and height of 0.5 cm using a puncher, and was placed in a vacuum drying oven and dried at 80°C under a vacuum degree of -20 kPa for 2 h; then, the dried cuttlefish bone cylinder was placed in a quartz boat and pyrolyzed in a tube furnace at 300°C under N2 atmosphere for 2 h to obtain a cuttlefish bone pyrolysis derivative material.

[0054] Example 2

[0055] The intact structure of cuttlefish bone was selected and washed clean with ultrapure water, and then the cleaned cuttlefish bone was cut into a cylindrical block with a diameter and height of 0.5 cm using a puncher, and was placed in a vacuum drying oven and dried at 80°C under a vacuum degree of -20 kPa for 2 h; then, the dried cuttlefish bone cylinder was placed in a quartz boat and pyrolyzed in a tube furnace at 500°C under N2 atmosphere for 2 h to obtain a cuttlefish bone pyrolysis derivative material (pore volume of 0.03 m 2 / g, specific surface area of 4.21 m 2 / g).

[0056] Comparative Example 1

[0057] The corn straw was selected as a raw material to prepare biochar: the corn straw was washed clean with ultrapure water and then dried in a vacuum drying oven at 60°C under a vacuum degree of -20 kPa until the weight was constant; the dried corn straw was crushed and passed through a 60-mesh sieve, and then carbonized in a muffle furnace at 500°C under N2 atmosphere for 4 h to obtain corn straw biochar.

[0058] Performance test

[0059] (1) The cuttlefish bone pyrolysis derivative material prepared in Example 1 was subjected to scanning electron microscopy, and the results are shown in Figure 1 .

[0060] As can be seen from Figure 1 , the cuttlefish bone pyrolysis derivative material is mainly composed of a calcium carbonate skeleton with a regularly arranged pore structure, and the distance between the pores of the skeleton is 200 μm, and the pore wall is covered with an organic carbon film.

[0061] (2) The cuttlefish bone pyrolysis derivative material prepared in Example 1 was subjected to Fourier infrared spectroscopy test, and the results are shown in Figure 2 .

[0062] As can be seen from Figure 2 , the proportion of the calcium carbonate skeleton in the cuttlefish bone pyrolysis derivative material is as high as more than 90%, and the mass percentage of the organic carbon film covered on the pore wall is 3%.

[0063] (3) Cd(II) was selected as the heavy metal research object. 4.8 mg of the cuttlebone pyrolysis derivative material prepared in Example 1 was weighed into a 40 mL brown ampoule, and then mixed with 40 mL of Cd at different initial concentrations (2-60 mg / L). 2+ The solutions were mixed, and the mixed samples were shaken in a shaker at 25°C for 72 hours. After the reaction was complete, the samples were centrifuged at 3000 rpm for 10 minutes. After standing, the supernatant was collected, and the Cd concentration in the supernatant was measured using a flame atomic absorption spectrometer. 2+ The concentration of Cd was calculated, and the effect of cuttlebone pyrolysis derivatives on Cd was obtained. 2+ The adsorption capacity of Cd was determined. This was compared with that of hematite, TiO2, corn straw biochar, chitin, lignin sulfonate-hematite, hydroxyapatite / bentonite, iron manganese oxide-biochar, and cross-linked chitosan. 2+ The adsorption effects were compared, and the results are shown in Table 1.

[0064] Table 1 shows the effect of different materials on Cd. 2+ adsorption effect

[0065] Adsorbent Adsorbate Adsorption capacity (mg / g) Sepia hot pyrolysis derived material Cd(II) 452.14 Hematite Cd(II) 0.2 TiO2 Cd(II) 0.27 Corn stover biochar Cd(II) 12.42 Chitin Cd(II) 12.5 Lignosulfonate-hematite Cd(II) 39.03 Hydroxyapatite / bentonite Cd(II) 98 Iron-manganese oxide-biochar Cd(II) 120.77 Crosslinked chitosan Cd(II) 213

[0066] As shown in Table 1, the cuttlebone pyrolysis-derived material of the present invention is effective against Cd. 2+ Its adsorption capacity is significantly higher than that of other adsorbent materials.

[0067] (4) Weigh approximately 4.8 mg of the cuttlebone pyrolysis-derived material prepared in Example 2 into a 40 mL brown ampoule. Then, mix it with 40 mL of salmon sperm (hsDNA) solutions of different initial concentrations (1–64 mg / L), using 0.01 mol / L Tris-HCl buffer as the background solution. The mixed samples were shaken in a shaker at 25°C for 72 h. After sufficient reaction, the samples were centrifuged at 3000 r / min for 10 min. After standing, the supernatant was collected, and the concentration of hsDNA in the supernatant was measured using a UV spectrophotometer. The adsorption capacity of the cuttlebone pyrolysis-derived material for hsDNA was calculated. The adsorption effects were compared with those of Na-saturated montmorillonite, Fe-saturated montmorillonite, palygorskite, sericite, Ce-modified sludge biochar, rice biochar, pine biochar, and magnetic biochar. The results are shown in Table 2.

[0068] Table 2 shows the adsorption effect of different materials on eDNA.

[0069] Adsorbent Adsorbate Adsorption capacity (mg / g) Sepia hot pyrolysis derived material eDNA 88.7 Na-saturated montmorillonite eDNA 10.7 Fe-saturated montmorillonite eDNA 21.3 Rectorite eDNA 34.4 Serizite eDNA 1.4 Ce-modified sludge biochar eDNA 8.5 Rice biochar eDNA 0.6 Pine biochar eDNA 1 Magnetic biochar eDNA 5.0

[0070] As can be seen from Table 2, the adsorption amount of eDNA of the cuttlebone pyrolysis derived material of the present application is significantly higher than that of other adsorption materials. Meanwhile, in combination with the results of Table 1, it can be seen that the cuttlebone biochar has excellent removal effect on both heavy metals and eDNA.

[0071] (5) Select salmon sperm (hsDNA) and Cd as the research objects of eDNA and heavy metals respectively, take 4.8 mg of the cuttlebone pyrolysis derived material prepared in Example 2 in a 40 mL brown an spectrum glass bottle, and add 20 mL of 30 mg / L of hsDNA solution and 80 mg / L of Cd 2+ solution respectively. The mixed sample continues to be shaken in a shaking table at 25℃, and the reaction time is 1 h, 3 h, 5 h, 12 h and 24 h respectively. After the reaction is completed, the sample is placed in a centrifuge at a speed of 3000 r / min for 10 min. After standing, the supernatant is taken, and the concentration of hsDNA and Cd 2+ in the supernatant is determined by ultraviolet spectrophotometer and flame atomic absorption spectrometer respectively. The adsorption effect of the cuttlebone pyrolysis derived material on Cd 2+ and hsDNA in water body at different reaction times is shown in Table 3.

[0072] Table 3 Adsorption effect of cuttlebone pyrolysis derived material on Cd 2+ and hsDNA in water body at different reaction times

[0073] Reaction time (h) 1 3 5 12 24 Cd 2+ Adsorption capacity (mg / g) 15.25 15.74 20.70 33.99 40.90 hsDNA adsorption capacity (mg / g) 14.74 15.74 17.19 19.56 22.56

[0074] As can be seen from Table 3, the adsorption amount of the cuttlebone pyrolysis derived material provided by the present application on Cd 2+ and hsDNA in water body gradually increases with the extension of the reaction time, and has a good synchronous adsorption effect on both.

[0075] (6) Take 4.8 mg of the cuttlebone pyrolysis derived material prepared in Example 1 in a 40 mL brown an spectrum glass bottle, then add 20 mL of 80 mg / L of Cd 2+ solution and mix with 20 mL of hsDNA solution with different concentrations respectively. The mixed sample is shaken in a shaking table at 25℃ for 72 h, and the sample after full reaction is centrifuged in a centrifuge at a speed of 3000 r / min for 10 min. After standing, the supernatant is taken, and the concentration of Cd 2+ in the supernatant is measured by flame atomic absorption spectrometer, and the adsorption amount of the cuttlebone pyrolysis derived material on Cd 2+ is calculated as 98 mg / g. The concentration of hsDNA in the supernatant is determined by ultraviolet spectrophotometer, and the results are shown in Table 4.

[0076] Table 4 Adsorption effect of cuttlebone pyrolysis derived material on hsDNA in wastewater containing Cd 2+ ​

[0077] hsDNA initial concentration (mg / L) 1 2 4 8 16 32 64 hsDNA adsorption capacity (mg / g) 6.28 8.48 10.67 16.87 26.80 43.89 79.80

[0078] As shown in Table 4, when the initial concentration of Cd 2+ in the water body is 40 mg / L and the initial concentration of hsDNA is 1-64 mg / L, the adsorption amount of the sea squirt pen shell pyrolysis derivative material for Cd 2+ and hsDNA in the wastewater is 6.28-79.80 mg / g, and the adsorption effect of the sea squirt pen shell pyrolysis derivative material for Cd 2+ and hsDNA is excellent.

[0079] (7) After the reaction in (6), the sample is subjected to solid-liquid separation, the wastewater after the reaction is transferred out of the brown an spectrum glass bottle by means of a dropper, and then 0.2 mol / L phosphate (disodium hydrogen phosphate-sodium dihydrogen phosphate) buffer solution is added to mix with the sea squirt pen shell pyrolysis derivative material for adsorbing pollutants. The mixed sample is oscillated in a shaking table at 25°C for 72 h, the sample after full reaction is centrifuged in a centrifuge at a speed of 3000 r / min for 10 min, and after standing, the supernatant is taken to measure the concentration of the pollutants in the supernatant and calculate the desorption rate. The operation is repeated for 3 times, and the regeneration rate of the material after adsorption is calculated to be more than 80%.

[0080] (8) 4.8 mg of the sea squirt pen shell pyrolysis derivative material prepared in Example 1 is weighed in a 40 mL brown an spectrum glass bottle, and then 20 mL of 200 mg / L hsDNA solution is added to mix with 20 mL of Cd 2+ solution with different concentrations. The mixed sample is oscillated in a shaking table at 2°C for 72 h, the sample after full reaction is centrifuged in a centrifuge at a speed of 3000 r / min for 10 min, and after standing, the supernatant is taken to measure the concentration of the hsDNA in the supernatant by means of a UV spectrophotometer, and the adsorption amount of the sea squirt pen shell pyrolysis derivative material for the hsDNA is calculated to be 119 mg / g. The concentration of Cd 2+ in the supernatant is measured by means of a flame atomic absorption spectrometer, and the results are shown in Table 5.

[0081] Table 5 Adsorption effect of the sea squirt pen shell pyrolysis derivative material for Cd 2+ in the wastewater containing hsDNA

[0082]

[0083] As shown in Table 5, when the initial concentration of hsDNA in the water body is 100 mg / L and the initial concentration of Cd 2+ is 2-60 mg / L, the adsorption amount of the sea squirt pen shell pyrolysis derivative material for Cd 2+ in the wastewater containing hsDNA is 9.90-546.96 mg / g, and the adsorption effect of the sea squirt pen shell pyrolysis derivative material for Cd 2+ and hsDNA is excellent.

[0084] (9) 100 mg of corn stalk biochar prepared in Comparative Example 1 was weighed into a 40 mL brown ambo glass bottle containing 20 mL of Tris-HCl buffer (pH about 5.0), followed by 10 mL of 448 mg / L Cd solution and 10 mL of hsDNA solution with different concentrations, respectively. The mixed sample was shaken in a shaker at 25°C for 72 h, and then centrifuged at 3000 r / min for 10 min. The supernatant was obtained after standing, and the concentration of Cd in the supernatant was measured by flame atomic absorption spectrometer. The saturated adsorption capacity of corn stalk biochar for Cd was calculated to be 28 mg / g. 2+ 2+ 2+ The concentration of hsDNA in the supernatant was measured by ultraviolet spectrophotometer, and the results are shown in Table 6.

[0085] Table 6 Adsorption effect of corn stalk biochar on hsDNA in wastewater containing Cd 2+

[0086] hsDNA initial concentration (mg / L) 2 5 10 15 20 30 40 60 hsDNA adsorption capacity (mg / g) 0.69 1.77 3.29 3.87 4.51 5.99 6.92 8.28

[0087] As can be seen from Table 6, when the initial concentration of Cd in the water body was 112 mg / L and the initial concentration of hsDNA was 2-60 mg / L, the adsorption capacity of corn stalk biochar for hsDNA in wastewater containing Cd was 0.69-8.28 mg / g, and the simultaneous adsorption effect of corn stalk biochar for Cd and hsDNA was poor. 2+ 2+ 2+

[0088] Although the above examples have made a detailed description of the present application, it is only a part of the embodiments of the present application but not all the embodiments, and other embodiments can be obtained according to the present embodiments without creativity, which all belong to the protection scope of the present application.​​​​​​

Claims

1. A method of simultaneously removing heavy metals and eDNA from a water body, characterized in that, The method comprises the following steps: adding the sepia pyrolysis derived adsorption material into the water body for adsorption treatment; the sepia pyrolysis derived adsorption material comprises a calcium carbonate skeleton with a porous house frame type pore structure and an organic carbon film covering the surface of the calcium carbonate skeleton and the pore wall; the spacing of the pores is 50-200 μm; the mass percentage of the calcium carbonate skeleton in the sepia pyrolysis derived adsorption material is 95-97%, and the mass percentage of the organic carbon film is 3-5%; The heavy metal ions in the water body are Cd 2+ ; the eDNA in the water body includes one or more of herring sperm DNA, salmon sperm DNA, ampicillin-resistant gene, and calf thymus DNA; the concentration of heavy metal ions in the water body is 1-60 mg / L, and the concentration of eDNA in the water body is 1-64 mg / L; the adding amount of the sepia pyrolysis derived adsorption material is 4.8-50 mg / L.

2. The method of claim 1, wherein, The preparation method of the sepia pyrolysis derived adsorption material comprises the following steps: drying and pyrolyzing the sepia in sequence to obtain the sepia pyrolysis derived adsorption material.

3. The method of claim 2, wherein, The pyrolysis temperature is 300-600 ℃, and the holding time is 1-2 h.

4. The method according to claim 2 or 3, characterized in that, The pyrolysis is carried out under anoxic condition or limited oxygen condition; the limited oxygen condition is to control the volume content of oxygen to be lower than 1%.

5. The method of claim 1, wherein, The adsorption treatment temperature is 2-40 ℃, and the time is 1-7 d.

Images