A microbial immobilization material for treating polluted water and a preparation method thereof

Abstract

The present application discloses a microorganism fixing material for treating polluted water and a preparation method thereof. On the one hand, the present application provides a microorganism fixing material for treating polluted water, comprising a basalt porous ceramsite carrier, wherein the particle size of the basalt porous ceramsite carrier is not greater than 10 mm, and the specific surface area is not less than 10 m 2 / g, porosity not less than 70%; a composite nanolayer is arranged on the surface and in the pores of the basalt porous ceramsite carrier, the components of the composite nanolayer include nano-conductive diamond, nano-gold and nano-ferroferric oxide, and the thickness of the composite nanolayer is not more than 800nm. On the other hand, the present application also provides a preparation method and application of the above-mentioned microbial fixation material for polluted water treatment. The present application can effectively provide protection for microorganisms during the repair and purification of water pollution, so that microorganisms can be fixed and proliferated, and can also improve the efficiency of pollution repair.

Description

Technical Field

[0001] The present application relates to the technical field of microorganism fixation, and in particular to a microorganism fixation material for treating polluted water and a preparation method thereof. Background Art

[0002] With the acceleration of urbanization and the increasing prominence of environmental pollution, water ecological restoration has become an important means of protecting water resources and maintaining ecological balance. At present, there are two main methods of water ecological restoration: biological restoration and engineering restoration. Engineering restoration is to repair polluted water bodies through construction equipment and means, supplemented by physical and chemical methods, such as our common lake water replacement and lake dredging. This restoration method is costly, and construction will produce new solid waste. It is only used for special water bodies in small areas. Biological restoration is to remove pollutants from water bodies by planting aquatic plants and breeding microorganisms or fish in water bodies through the adsorption, absorption and degradation of aquatic plants, and the eating, digestion and absorption of microorganisms or fish. This restoration method has low cost and small secondary pollution; although the restoration cycle is long, after restoration, the ecological environment of the water body can be effectively maintained for a long time, which is currently the preferred water pollution restoration method.

[0003] However, due to long-term pollution, the soil at the bottom of the polluted water body will gather a large number of microorganisms and bacteria, and there will be toxin accumulation, which will seriously inhibit the growth of aquatic plants, microorganisms and fish. For the bottom soil of polluted water bodies, the current treatment methods can only be dredging through construction or repairing through biological treatment. Engineering construction will generate new solid waste and the cost is high; while biological treatment needs to solve the problem that microorganisms are difficult to attach and fix.

[0004] Microbial immobilization technology refers to the technology of using physical or chemical methods to fix microorganisms in specific materials through adsorption, covalent binding, interception and embedding, and then adding the whole to the reaction system. Compared with traditional microbial technology, this technology has the advantages of high biological concentration, simple solid-liquid separation, strong stress resistance, good stability, and strong mechanical properties. Since it was proposed in the 1960s, immobilization technology has become a research hotspot in the field of microbial applications and is widely used in environmental protection, food, medicine and energy. The use of microbial immobilization technology can solve the problem of microbial attachment to a certain extent. However, water pollution, especially soil pollution at the bottom of polluted water bodies, is relatively complicated. The current microbial immobilization technology cannot solve the problem of efficient proliferation of purification microorganisms in the soil at the bottom of polluted water bodies, and therefore it is difficult to meet the needs of water restoration. Summary of the invention

[0005] In order to solve at least one of the above technical problems, a fixing material is developed that can effectively provide protection for microorganisms during water pollution repair and purification, so that microorganisms can be fixed and proliferated, and the pollution repair efficiency can be improved. The present application provides a microbial fixing material for polluted water treatment and a preparation method thereof.

[0006] On the one hand, the present application provides a microbial immobilization material for treating polluted water, comprising a basalt porous ceramsite carrier, wherein the particle size of the basalt porous ceramsite carrier is not greater than 10 mm, and the specific surface area is not less than 10 m 2 / g, and a porosity of not less than 70%; a composite nanolayer is arranged on the surface and in the pores of the basalt porous ceramsite carrier, the components of the composite nanolayer include nano-conductive diamond, nano-gold and nano-ferroferric oxide, and the thickness of the composite nanolayer is not more than 800nm.

[0007] By adopting the above technical solution, the present application uses basalt porous ceramsite carrier as a fixed carrier of microorganisms, the porosity of the carrier is not less than 70%, and the specific surface area is not less than 10m 2 / g, and basalt is a natural material, which is very friendly to microorganisms. It can ensure that the microbial fixing material of the present application can allow microorganisms to gather and attach, effectively fix microorganisms, and solve the problem that microorganisms are difficult to attach to the soil at the bottom of the water body. Moreover, it will not cause secondary pollution when placed in the water body for a long time; the present application fixes a composite nanolayer of nano-conductive diamond, nano-gold and nano-ferroferric oxide in the basalt porous ceramsite carrier. Nano-gold combined with nano-ferroferric oxide can effectively catalyze the degradation of organic pollutants. Nano-conductive diamond has a higher potential window. Under the action of nano-gold catalyst and carbon-containing particles produced by the degradation of organic pollutants, it can catalyze the oxidation of organic pollutants, thereby greatly improving the decomposition of polluted soil at the bottom of the water body and pollutants in the water body. Efficiency, ensuring that toxic organic pollutants and harmful pollutants around the basalt porous expanded clay carrier are decomposed, providing effective protection for the microorganisms in the carrier, ensuring that they can grow and proliferate in the carrier, and providing a beneficial microenvironment for the fixation of microorganisms; the present application uses a basalt porous expanded clay carrier as an inorganic carrier, combined with a composite nanolayer, and basalt as an environmentally friendly natural material. The porous expanded clay carrier has extremely strong chemical stability, and among the nanomaterials used in the composite nanolayer, nanogold can effectively wrap nano-ferroferric tetroxide, and the nano-conductive diamond layer can play a catalytic oxidation role. When treating pollutants, the divalent iron formed in the catalytic process can be quickly oxidized into trivalent iron, ensuring the stability of the coating, and ensuring that the microbial fixation material of the present application has a long service life.

[0008] Optionally, the mass proportions of the raw material components of the basalt porous ceramsite carrier include: 20-40 parts of porous basalt powder, 20-30 parts of attapulgite, 10-20 parts of alumina powder, 16-22 parts of pore-forming agent, and 12-18 parts of adhesive.

[0009] Further optionally, the pore-forming agent is ammonium bicarbonate powder, and the adhesive is a phenolic resin binder.

[0010] Further optionally, the particle sizes of the porous basalt powder, attapulgite and alumina powder are 50-100 μm, and the particle size of the ammonium bicarbonate powder is 400-500 μm.

[0011] Optionally, the particle size of each component of the composite nanolayer is not greater than 200 nm.

[0012] By adopting the above-mentioned technical scheme, the present application adopts a specific raw material component ratio of basalt porous expanded clay carrier, and at the same time adopts a specific pore-forming agent, combined with particle size grading, which can effectively ensure that the prepared basalt porous expanded clay carrier has larger pores, which can facilitate the subsequent loading of the composite nanolayer and effectively improve the performance of the microbial fixation carrier.

[0013] In a second aspect, the present application also provides a method for preparing the above-mentioned microbial immobilization material for treating polluted water, comprising the following steps:

[0014] S1, preparing basalt porous ceramsite carrier;

[0015] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a ferric hydroxide colloidal solution, ultrasonically treating it for 15 to 30 minutes, taking it out, drying it, and then heating it at a temperature of 100 to 120° C. for more than 1 hour to obtain a ceramsite carrier with nano-iron tetroxide attached thereto;

[0016] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 15 to 30 minutes, and then boiling for 15 to 20 minutes, taking out, washing, and drying to obtain the ceramsite carrier with nano-gold;

[0017] S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating for 15 to 30 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached;

[0018] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited on the surface and pores of the porous ceramsite carrier with nano-conductive diamonds attached thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

[0019] Through the above technical scheme, the present application adopts crystallized basalt porous ceramsite carrier as a microbial fixation carrier, which has very stable chemical properties. When preparing the subsequent deposition layer, no impurity elements will be released, which effectively guarantees the quality of each nanolayer in the final microbial fixation material; the present application adopts the method of low-temperature oxidation of ferric hydroxide to load nano-iron tetroxide in the pores of the porous ceramsite carrier, and then adopts the chloroauric acid reduction method to load nano-gold in the pores of the porous ceramsite carrier, and finally adopts the chemical vapor deposition method to directionally deposit nano-conductive diamond in the pores of the porous ceramsite carrier to prepare the microbial fixation material of the present application; the nano-gold layer in the pores of the prepared microbial fixation material can form a wrapping protection for the nano-iron tetroxide layer, and the chemically stable nano-gold layer can form a wrapping protection for the nano-iron tetroxide layer, and the nano-gold layer with extremely strong chemical stability can form a wrapping protection for the nano-iron tetroxide layer. The nano-conductive diamond mesoporous layer can protect nano-ferroferric oxide and nano-gold again, and the porous structure of the nano-conductive diamond mesoporous layer will not affect the catalytic effect of nano-ferroferric oxide and nano-gold on pollutants, that is, the catalytic decomposition performance of the microbial fixation material on pollutants is guaranteed, and the service life of the microbial fixation material is greatly improved; the application adopts the preparation steps of first depositing nano-ferroferric oxide, then depositing nano-gold, and finally preparing the nano-conductive diamond mesoporous layer, and the preparation of each layer adopts the corresponding process method, which can ensure that the nano-ferroferric oxide will not be damaged when the nano-gold is deposited, and when the nano-conductive diamond mesoporous layer is deposited, it can provide protection for the nano-gold in a reducing atmosphere to prevent it from being oxidized, thereby effectively ensuring the quality of the fixation material.

[0020] Optionally, the step S1 includes the following steps:

[0021] S1-1, fully mixing the raw material components of the basalt porous ceramsite carrier to prepare a slurry;

[0022] S1-2, placing the slurry obtained in step S1-1 in a mixing and granulating machine to form ceramsite particles of target particle size;

[0023] S1-3, heating the ceramsite green body particles obtained in step S1-2 to 200-240°C in a vacuum furnace, keeping the temperature for 30-60 minutes, then heating to 960-980°C, sintering at high temperature, and air cooling to room temperature to obtain a basalt porous ceramsite carrier.

[0024] Optionally, in the mixed solution of sodium citrate and chloroauric acid, the mass fraction of sodium citrate is 0.1-0.15%, and the mass fraction of chloroauric acid is 0.15-0.2%.

[0025] By adopting the above technical scheme, the present application uses low concentrations of sodium citrate and chloroauric acid to prepare a mixed solution as a raw material for preparing nano-gold, which can effectively avoid the reduction effect of sodium citrate on nano-ferroferric oxide, ensure that the ferroferric oxide is not reduced, and ensure the quality and performance of the microbial fixation material.

[0026] Optionally, in step S4, the nano-conductive diamond suspension is an anhydrous ethanol suspension of nano-conductive diamond, and the mass fraction of nano-conductive diamond is 10-15%.

[0027] On the third aspect, the present application also provides the application of the above-mentioned microbial fixation material for polluted water treatment in the field of sediment purification and restoration of natural water bodies.

[0028] In summary, the present invention includes at least one of the following beneficial technical effects:

[0029] 1. This application uses basalt porous ceramsite carrier as a fixed carrier for microorganisms. The porosity of the carrier is not less than 70% and the specific surface area is not less than 10m 2 / g, and basalt is a natural material, which is very friendly to microorganisms. It can ensure that the microbial fixation material of the present application can allow microorganisms to aggregate and attach, effectively fix the microorganisms, solve the problem that microorganisms are difficult to attach to the soil at the bottom of the water body, and be placed in the water body for a long time without causing secondary pollution.

[0030] 2. In the present application, a composite nanolayer of nano-conductive diamond, nano-gold and nano-ferroferric oxide is fixedly loaded in a basalt porous ceramsite carrier. Nano-gold combined with nano-ferroferric oxide can effectively catalyze the degradation of organic pollutants. Nano-conductive diamond has a high potential window. Under the action of nano-gold catalyst and carbon-containing particles produced by the degradation of organic pollutants, it can catalyze the oxidation of organic pollutants, thereby greatly improving the decomposition efficiency of polluted soil at the bottom of the water body and pollutants in the water body, ensuring that toxic organic pollutants and harmful pollutants around the basalt porous ceramsite carrier are decomposed, providing effective protection for the microorganisms in the carrier, ensuring that they can grow and proliferate in the carrier, and providing a beneficial microenvironment for the fixation of microorganisms.

[0031] 3. The present application uses a basalt porous expanded clay carrier as an inorganic carrier in combination with a composite nanolayer. Basalt is an environmentally friendly natural material, and the porous expanded clay carrier obtained has extremely strong chemical stability. Among the nanomaterials used in the composite nanolayer, nanogold can effectively wrap nano-ferroferric tetroxide, and the nano-conductive diamond layer can play a catalytic oxidation role. When treating pollutants, it can quickly oxidize the divalent iron formed in the catalytic process into trivalent iron, thereby ensuring the stability of the coating and ensuring that the microbial fixation material of the present application has a long service life.

[0032] 4. This application uses crystallized basalt porous ceramsite carrier as a microbial fixation carrier, which has very stable chemical properties. When preparing subsequent sedimentary layers, no impurity elements will be released, effectively ensuring the quality of each nanolayer in the final microbial fixation material.

[0033] 5. The present application adopts the method of low-temperature oxidation of ferric hydroxide to load nano-ferroferric oxide in the pores of a porous ceramsite carrier, and then adopts the chloroauric acid reduction method to load nano-gold in the pores of the porous ceramsite carrier, and finally adopts the chemical vapor deposition method to directionally deposit nano-conductive diamond in the pores of the porous ceramsite carrier to prepare the microbial fixation material of the present application; in the prepared microbial fixation material, the nano-gold layer in the pores can form a wrapping protection for the nano-ferroferric oxide layer, and the nano-conductive diamond mesoporous layer with extremely strong chemical stability can protect the nano-ferroferric oxide and nano-gold again, and the porous structure of the nano-conductive diamond mesoporous layer will not affect the catalytic effect of nano-ferroferric oxide and nano-gold on pollutants, that is, the catalytic decomposition performance of the microbial fixation material on pollutants is guaranteed, and the service life of the microbial fixation material is greatly improved.

[0034] 6. The present application adopts the preparation steps of first depositing nano-iron tetroxide, then depositing nano-gold, and finally preparing the nano-conductive diamond mesoporous layer, and the preparation of each layer adopts a corresponding process method, which can ensure that the nano-iron tetroxide will not be damaged when the nano-gold is deposited, and when the nano-conductive diamond mesoporous layer is deposited, it can provide protection for the nano-gold in a reducing atmosphere to prevent it from being oxidized, thereby effectively ensuring the quality of the fixed material. DETAILED DESCRIPTION

[0035] The present application is further described in detail below with reference to the embodiments.

[0036] The present application provides a microbial fixation material for treating polluted water, comprising a basalt porous ceramsite carrier, wherein the particle size of the basalt porous ceramsite carrier is not greater than 10 mm, and the specific surface area is not less than 10 m 2 / g, and a porosity of not less than 70%; a composite nanolayer is arranged on the surface and in the pores of the basalt porous ceramsite carrier, the components of the composite nanolayer include nano-conductive diamond, nano-gold and nano-ferroferric oxide, and the thickness of the composite nanolayer is not more than 800nm.

[0037] The method for preparing the microbial immobilization material for treating polluted water of the present application comprises the following steps:

[0038] S1, preparing basalt porous ceramsite carrier;

[0039] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a ferric hydroxide colloidal solution, ultrasonically treating it for 15 to 30 minutes, taking it out, drying it, and then heating it at a temperature of 100 to 120° C. for more than 1 hour to obtain a ceramsite carrier with nano-iron tetroxide attached thereto;

[0040] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 15 to 30 minutes, and then boiling for 15 to 20 minutes, taking out, washing, and drying to obtain the ceramsite carrier with nano-gold;

[0041] S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating for 15 to 30 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached;

[0042] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited on the surface and pores of the porous ceramsite carrier with nano-conductive diamonds attached thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

[0043] The basalt porous ceramsite carrier in step S1 can be prepared by granulating and sintering raw materials using powder metallurgy.

[0044] The following is the preparation example of this application

[0045] In the preparation example of the present application, the porous basalt powder, attapulgite and alumina powder are all selected as powders with a particle size of 120-150 μm; the pore-forming agent is ammonium bicarbonate powder, and the particle size of the powder is 120-150 μm.

[0046] Preparation Example 1

[0047] The basalt porous ceramsite carrier of this preparation example has the following mass proportions of the raw material components: 20 parts of porous basalt powder, 20 parts of attapulgite, 10 parts of alumina powder, 16 parts of pore-forming agent, and 12 parts of phenolic resin binder.

[0048] The preparation of the basalt porous ceramsite carrier of this preparation example includes the following steps:

[0049] S1-1, accurately weighing the raw material components of the basalt porous ceramsite carrier according to the ratio, and then fully mixing them to form a slurry;

[0050] S1-2, placing the slurry obtained in step S1-1 in a mixing and granulating machine to form ceramsite green body particles with a particle size of 6-10 mm;

[0051] S1-3, heating the ceramsite green body particles obtained in step S1-2 to 200° C. in a vacuum furnace, keeping the temperature for 60 minutes, then heating to 960° C., sintering at high temperature, and air cooling to room temperature to obtain a basalt porous ceramsite carrier.

[0052] Preparation Example 2

[0053] The basalt porous ceramsite carrier of this preparation example has the following mass proportions of the raw material components: 40 parts of porous basalt powder, 30 parts of attapulgite, 20 parts of alumina powder, 22 parts of pore-forming agent, and 18 parts of phenolic resin binder.

[0054] The preparation of the basalt porous ceramsite carrier of this preparation example includes the following steps:

[0055] S1-1, accurately weighing the raw material components of the basalt porous ceramsite carrier according to the ratio, and then fully mixing them to form a slurry;

[0056] S1-2, placing the slurry obtained in step S1-1 in a mixing and granulating machine to form ceramsite green body particles with a particle size of 6-10 mm;

[0057] S1-3, heating the ceramsite green body particles obtained in step S1-2 to 240° C. in a vacuum furnace, keeping the temperature for 30 minutes, then heating to 980° C., sintering at high temperature, and air cooling to room temperature to obtain a basalt porous ceramsite carrier.

[0058] Preparation Example 3

[0059] The basalt porous ceramsite carrier of this preparation example has the following mass proportions of the raw material components: 32 parts of porous basalt powder, 22 parts of attapulgite, 14 parts of alumina powder, 20 parts of pore-forming agent, and 14 parts of phenolic resin binder.

[0060] The preparation of the basalt porous ceramsite carrier of this preparation example includes the following steps:

[0061] S1-1, accurately weighing the raw material components of the basalt porous ceramsite carrier according to the ratio, and then fully mixing them to form a slurry;

[0062] S1-2, placing the slurry obtained in step S1-1 in a mixing and granulating machine to form ceramsite green body particles with a particle size of 6-10 mm;

[0063] S1-3, heating the ceramsite green body particles obtained in step S1-2 to 220° C. in a vacuum furnace, keeping the temperature for 50 minutes, then heating to 970° C., sintering at high temperature, and air cooling to room temperature to obtain a basalt porous ceramsite carrier.

[0064] Preparation Example 4

[0065] The basalt porous ceramsite carrier of this preparation example has the following mass proportions of the raw material components: 20 parts of porous basalt powder, 25 parts of attapulgite, 15 parts of alumina powder, 14 parts of pore-forming agent, and 16 parts of phenolic resin binder.

[0066] The preparation of the basalt porous ceramsite carrier of this preparation example includes the following steps:

[0067] S1-1, accurately weighing the raw material components of the basalt porous ceramsite carrier according to the ratio, and then fully mixing them to form a slurry;

[0068] S1-2, placing the slurry obtained in step S1-1 in a mixing and granulating machine to form ceramsite green body particles with a particle size of 6-10 mm;

[0069] S1-3, heating the ceramsite green body particles obtained in step S1-2 to 220° C. in a vacuum furnace, keeping the temperature for 50 minutes, then heating to 970° C., sintering at high temperature, and air cooling to room temperature to obtain a basalt porous ceramsite carrier.

[0070] The porosity and specific surface area of ​​the basalt porous ceramsite carriers prepared in Preparation Examples 1 to 4 of the present application were tested, and the results are shown in Table 1 below.

[0071] Table 1 Porosity and specific surface area of ​​basalt porous ceramsite carriers prepared in Preparation Examples 1 to 4

[0072]

[0073] The following are examples of the present application:

[0074] Embodiments 1 to 7

[0075] The basalt porous ceramsite carrier of Examples 1 to 7 of the present application adopts the basalt porous ceramsite carrier prepared in Preparation Example 4.

[0076] Example 1

[0077] The method for preparing the microbial immobilization material for treating polluted water in this embodiment comprises the following steps:

[0078] S1. Screen and remove the broken ceramsite from the basalt porous ceramsite carrier to use it as the basalt porous ceramsite carrier.

[0079] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a 1.5% iron hydroxide colloidal solution, ultrasonically treating it for 15 minutes, taking it out, drying it, and then heating it at 100°C for 1 hour to obtain a ceramsite carrier with nano-iron tetroxide. In the nano-iron tetroxide layer, the particle size of the nano-iron tetroxide is 50-70nm, and the thickness of the nano-iron tetroxide layer is not more than 120nm.

[0080] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 15 minutes, and then boiling for 15 minutes, taking out, washing, and drying, to obtain a ceramsite carrier with nano-gold; the mixed solution used has a sodium citrate concentration of 0.5% and a chloroauric acid concentration of 0.25%. In the nano-gold layer, the particle size of the nano-gold is 80-100nm, and the thickness of the nano-gold layer is not more than 160nm.

[0081] S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating it for 15 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached; wherein the nano-conductive diamond suspension used has a solvent of anhydrous ethanol, a nano-conductive diamond concentration of 30%, and a particle size of 180-200nm.

[0082] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited in the pores of the porous ceramsite carrier with conductive diamond particles attached thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water.

[0083] In step S5, a DC arc plasma jet CVD system is used, and the deposition parameters are: B2H6 / CH4 / H2 / Ar is used as the deposition atmosphere, the B2H6 flow rate is set to 1 sccm, the CH4 flow rate is set to 150 sccm, the H2 flow rate is set to 5 SLM, the Ar flow rate is set to 12 SLM, the deposition temperature is set to 740°C, the deposition pressure is set to 3.5 kPa, and the deposition time is set to 18 min. The nano-conductive diamond mesoporous layer obtained by deposition has a particle size of 220-240 nm for the diamond grains, and the thickness of the nano-conductive diamond mesoporous layer is not greater than 400 nm.

[0084] Example 2

[0085] The method for preparing the microbial immobilization material for treating polluted water in this embodiment comprises the following steps:

[0086] S1. Screen and remove the broken ceramsite from the basalt porous ceramsite carrier to use it as the basalt porous ceramsite carrier.

[0087] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a 1.5% iron hydroxide colloidal solution, ultrasonically treating for 30 minutes, taking it out, drying it, and then heating it at 120°C for 1 hour to obtain a ceramsite carrier with nano-iron tetroxide. In the nano-iron tetroxide layer, the particle size of the nano-iron tetroxide is 60-80nm, and the thickness of the nano-iron tetroxide layer is not more than 180nm.

[0088] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 30 minutes, and then boiling for 30 minutes, taking out, washing, and drying to obtain a ceramsite carrier with nano-gold; the mixed solution used has a sodium citrate concentration of 0.5% and a chloroauric acid concentration of 0.25%. In the nano-gold layer, the particle size of the nano-gold is 80-100nm, and the thickness of the nano-gold layer is not more than 220nm.

[0089] S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating it for 30 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached; wherein the nano-conductive diamond suspension used has a solvent of anhydrous ethanol, a nano-conductive diamond concentration of 30%, and a particle size of 180-200nm.

[0090] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited in the pores of the porous ceramsite carrier with nano-conductive diamonds adhered thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

[0091] In step S5, a DC arc plasma jet CVD system is used, and the deposition parameters are: B2H6 / CH4 / H2 / Ar is used as the deposition atmosphere, the B2H6 flow rate is set to 1 sccm, the CH4 flow rate is set to 150 sccm, the H2 flow rate is set to 5 SLM, the Ar flow rate is set to 12 SLM, the deposition temperature is set to 740°C, the deposition pressure is set to 3.5 kPa, and the deposition time is set to 18 min. The nano-conductive diamond mesoporous layer obtained by deposition has a particle size of 220-240 nm for the diamond grains, and the thickness of the nano-conductive diamond mesoporous layer is not greater than 400 nm.

[0092] Example 3

[0093] The method for preparing the microbial immobilization material for treating polluted water in this embodiment comprises the following steps:

[0094] S1. The purchased basalt porous ceramsite carrier is screened and the broken ceramsite is removed to form the basalt porous ceramsite carrier.

[0095] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a 1% iron hydroxide colloidal solution, ultrasonically treating for 25 minutes, taking out, drying, and then heating at 115°C for 1.5 hours to obtain a ceramsite carrier with nano-iron tetroxide. In the nano-iron tetroxide layer, the particle size of the nano-iron tetroxide is 60-80nm, and the thickness of the nano-iron tetroxide layer is not more than 160nm.

[0096] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 25 minutes, and then boiling for 20 minutes, taking out, washing, and drying to obtain a ceramsite carrier with nano-gold; the mixed solution used has a sodium citrate concentration of 0.5% and a chloroauric acid concentration of 0.25%. In the nano-gold layer, the particle size of the nano-gold is 80-100nm, and the thickness of the nano-gold layer is not more than 200nm.

[0097] S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating it for 30 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached; wherein the nano-conductive diamond suspension used has a solvent of anhydrous ethanol, a nano-conductive diamond concentration of 30%, and a particle size of 180-200nm.

[0098] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited in the pores of the porous ceramsite carrier with nano-conductive diamonds adhered thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

[0099] In step S5, a DC arc plasma jet CVD system is used, and the deposition parameters are: B2H6 / CH4 / H2 / Ar is used as the deposition atmosphere, the B2H6 flow rate is set to 1 sccm, the CH4 flow rate is set to 150 sccm, the H2 flow rate is set to 5 SLM, the Ar flow rate is set to 12 SLM, the deposition temperature is set to 740°C, the deposition pressure is set to 3.5 kPa, and the deposition time is set to 18 min. The nano-conductive diamond mesoporous layer obtained by deposition has a particle size of 220-240 nm for the diamond grains, and the thickness of the nano-conductive diamond mesoporous layer is not greater than 400 nm.

[0100] Example 4

[0101] The method for preparing the microbial immobilization material for treating polluted water in this embodiment comprises the following steps:

[0102] S1. The purchased basalt porous ceramsite carrier is screened and the broken ceramsite is removed to form the basalt porous ceramsite carrier.

[0103] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a 1% iron hydroxide colloidal solution, ultrasonically treating for 25 minutes, taking out, drying, and then heating at 115°C for 1.5 hours to obtain a ceramsite carrier with nano-iron tetroxide. In the nano-iron tetroxide layer, the particle size of the nano-iron tetroxide is 60-80nm, and the thickness of the nano-iron tetroxide layer is not more than 160nm.

[0104] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 25 minutes, and then boiling for 20 minutes, taking out, washing, and drying to obtain a ceramsite carrier with nano-gold; the mixed solution used has a sodium citrate concentration of 0.1% and a chloroauric acid concentration of 0.15%. In the nano-gold layer, the particle size of the nano-gold particles is 40-60nm, and the thickness of the nano-gold layer is not more than 160nm.

[0105] S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating it for 30 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached; wherein the nano-conductive diamond suspension used has a solvent of anhydrous ethanol, a nano-conductive diamond concentration of 30%, and a particle size of 180-200nm.

[0106] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited in the pores of the porous ceramsite carrier with nano-conductive diamonds adhered thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

[0107] In step S5, a DC arc plasma jet CVD system is used, and the deposition parameters are: B2H6 / CH4 / H2 / Ar is used as the deposition atmosphere, the B2H6 flow rate is set to 1 sccm, the CH4 flow rate is set to 150 sccm, the H2 flow rate is set to 5 SLM, the Ar flow rate is set to 12 SLM, the deposition temperature is set to 740°C, the deposition pressure is set to 3.5 kPa, and the deposition time is set to 18 min. The nano-conductive diamond mesoporous layer obtained by deposition has a particle size of 220-240 nm for the diamond grains, and the thickness of the nano-conductive diamond mesoporous layer is not greater than 400 nm.

[0108] Example 5

[0109] The method for preparing the microbial immobilization material for treating polluted water in this embodiment comprises the following steps:

[0110] S1. The purchased basalt porous ceramsite carrier is screened and the broken ceramsite is removed to form the basalt porous ceramsite carrier.

[0111] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a 1% iron hydroxide colloidal solution, ultrasonically treating for 25 minutes, taking out, drying, and then heating at 115°C for 1.5 hours to obtain a ceramsite carrier with nano-iron tetroxide. In the nano-iron tetroxide layer, the particle size of the nano-iron tetroxide is 60-80nm, and the thickness of the nano-iron tetroxide layer is not more than 160nm.

[0112] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 25 minutes, and then boiling for 20 minutes, taking out, washing, and drying to obtain a ceramsite carrier with nano-gold; the mixed solution used has a sodium citrate concentration of 0.15% and a chloroauric acid concentration of 0.2%. In the nano-gold layer, the particle size of the nano-gold particles is 40-60nm, and the thickness of the nano-gold layer is not more than 170nm.

[0113] S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating it for 30 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached; wherein the nano-conductive diamond suspension used has a solvent of anhydrous ethanol, a nano-conductive diamond concentration of 30%, and a particle size of 180-200nm.

[0114] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited in the pores of the porous ceramsite carrier with nano-conductive diamonds adhered thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

[0115] In step S5, a DC arc plasma jet CVD system is used, and the deposition parameters are: B2H6 / CH4 / H2 / Ar is used as the deposition atmosphere, the B2H6 flow rate is set to 1 sccm, the CH4 flow rate is set to 150 sccm, the H2 flow rate is set to 5 SLM, the Ar flow rate is set to 12 SLM, the deposition temperature is set to 740°C, the deposition pressure is set to 3.5 kPa, and the deposition time is set to 18 min. The nano-conductive diamond mesoporous layer obtained by deposition has a particle size of 220-240 nm for the diamond grains, and the thickness of the nano-conductive diamond mesoporous layer is not greater than 400 nm.

[0116] Example 6

[0117] The method for preparing the microbial immobilization material for treating polluted water in this embodiment comprises the following steps:

[0118] S1. The purchased basalt porous ceramsite carrier is screened and the broken ceramsite is removed to form the basalt porous ceramsite carrier.

[0119] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a 1% iron hydroxide colloidal solution, ultrasonically treating for 25 minutes, taking out, drying, and then heating at 115°C for 1.5 hours to obtain a ceramsite carrier with nano-iron tetroxide. In the nano-iron tetroxide layer, the particle size of the nano-iron tetroxide is 60-80nm, and the thickness of the nano-iron tetroxide layer is not more than 160nm.

[0120] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 25 minutes, and then boiling for 20 minutes, taking out, washing, and drying to obtain a ceramsite carrier with nano-gold; the mixed solution used has a sodium citrate concentration of 0.1% and a chloroauric acid concentration of 0.15%. In the nano-gold layer, the particle size of the nano-gold particles is 40-60nm, and the thickness of the nano-gold layer is not more than 160nm.

[0121] S4. Place the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treat for 20 minutes, then take out and dry to obtain a porous ceramsite carrier with nano-conductive diamonds attached; wherein the nano-conductive diamond suspension used has anhydrous ethanol as solvent, a nano-conductive diamond concentration of 10%, and a particle size of 50-80 nm.

[0122] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited in the pores of the porous ceramsite carrier with nano-conductive diamonds adhered thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

[0123] In step S5, a DC arc plasma jet CVD system is used, and the deposition parameters are: B2H6 / CH4 / H2 / Ar is used as the deposition atmosphere, and the B2H6 flow rate is set to 1 sccm, the CH4 flow rate is set to 150 sccm, the H2 flow rate is set to 5 SLM, the Ar flow rate is set to 12 SLM, the deposition temperature is set to 740°C, the deposition pressure is set to 3.5 kPa, and the deposition time is set to 30 min. The nano-conductive diamond mesoporous layer obtained by deposition has a particle size of 120-150 nm for the diamond grains, and the thickness of the nano-conductive diamond mesoporous layer is not greater than 440 nm.

[0124] Example 7

[0125] The method for preparing the microbial immobilization material for treating polluted water in this embodiment comprises the following steps:

[0126] S1. The purchased basalt porous ceramsite carrier is screened and the broken ceramsite is removed to form the basalt porous ceramsite carrier.

[0127] S2, placing the basalt porous ceramsite carrier obtained in step S1 in a 1% iron hydroxide colloidal solution, ultrasonically treating for 25 minutes, taking out, drying, and then heating at 115°C for 1.5 hours to obtain a ceramsite carrier with nano-iron tetroxide. In the nano-iron tetroxide layer, the particle size of the nano-iron tetroxide is 60-80nm, and the thickness of the nano-iron tetroxide layer is not more than 160nm.

[0128] S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 25 minutes, and then boiling for 20 minutes, taking out, washing, and drying to obtain a ceramsite carrier with nano-gold; the mixed solution used has a sodium citrate concentration of 0.15% and a chloroauric acid concentration of 0.2%. In the nano-gold layer, the particle size of the nano-gold particles is 40-60nm, and the thickness of the nano-gold layer is not more than 170nm.

[0129] S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating it for 20 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached; wherein the nano-conductive diamond suspension used has anhydrous ethanol as solvent, a nano-conductive diamond concentration of 15%, and a particle size of 50-80nm.

[0130] S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited in the pores of the porous ceramsite carrier with nano-conductive diamonds adhered thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

[0131] In step S5, a DC arc plasma jet CVD system is used, and the deposition parameters are: B2H6 / CH4 / H2 / Ar is used as the deposition atmosphere, the B2H6 flow rate is set to 1 sccm, the CH4 flow rate is set to 150 sccm, the H2 flow rate is set to 5 SLM, the Ar flow rate is set to 12 SLM, the deposition temperature is set to 740°C, the deposition pressure is set to 3.5 kPa, and the deposition time is set to 35 min. The nano-conductive diamond mesoporous layer obtained by deposition has a particle size of 120-150 nm for the diamond grains, and the thickness of the nano-conductive diamond mesoporous layer is not greater than 460 nm.

[0132] The present application can control the thickness of the nano-conductive diamond mesoporous layer and the particle size of the diamond grains by controlling the particle size of the nano-diamond particles in the nano-conductive diamond suspension and the time of vapor deposition.

[0133] Embodiments 8 to 10

[0134] Examples 8 to 10 of the present application are basically the same as Example 7, except that different basalt porous ceramsite carriers are used. The basalt porous ceramsite carriers used in Examples 8 to 10 of the present application are the basalt porous ceramsite carriers prepared in Preparation Examples 1 to 3, respectively.

[0135] Embodiment 11

[0136] The difference between this embodiment and embodiment 10 is that when preparing the basalt porous ceramsite carrier, the porous basalt powder, attapulgite and alumina powder are all powders with a particle size of 50-100 μm.

[0137] Example 12

[0138] The difference between this embodiment and embodiment 11 is that when preparing the basalt porous ceramsite carrier, the pore-forming agent is a powder with a particle size of 400-500 μm.

[0139] The following is a comparative example of this application

[0140] Comparative Example 1

[0141] The comparative example of the present application adopts the solidified microorganism carrier-Guangzhou version of the granular carrier produced by Fujian Bayer Biotechnology Co., Ltd., with a particle size of about 5 cm.

[0142] Comparative Example 2

[0143] The difference between this comparative example and Example 12 is that nano-ferrosoferric oxide is not deposited.

[0144] Comparative Example 3

[0145] The difference between this comparative example and Example 12 is that no nano-conductive diamond mesoporous layer is deposited.

[0146] Comparative Example 4

[0147] The difference between this comparative example and Example 12 is that nano-gold is not deposited.

[0148] Comparative Example 5

[0149] The difference between this comparative example and Example 12 is that foamed alumina ceramic particles with the same particle size and porosity are used instead of basalt porous expanded clay as the fixed carrier.

[0150] Comparative Example 6

[0151] The difference between this comparative example and Example 12 is that the basalt porous ceramsite produced by Pingxiang Petrochemical Filler Co., Ltd. is used, and the particle size is 8-10 mm; sampling and testing show that the compressive strength of the ceramsite is 3.2-3.4 MPa, and the specific surface area is 4.2 m 2 / g, porosity 64%.

[0152] Performance Testing

[0153] The fixing materials of Examples 1 to 12 of the present application and the fixing materials of Comparative Examples 1 to 6 were subjected to performance testing to test their porosity and specific surface area. The specific test results are shown in Table 2.

[0154] Table 2 Performance test results of Examples 1 to 12 and Comparative Examples 1 to 4

[0155]

[0156] From the data in Table 2, it can be seen that the specific surface area and porosity of the fixing materials prepared in Examples 1 to 12 of the present application are significantly higher than the commercially available fixing materials in Comparative Example 1, and the fixing materials prepared using commercially available porous carriers in Comparative Examples 5 and 6; the specific surface area and porosity of the fixing materials in Examples 8 to 12 of the present application are significantly higher than the fixing materials in Examples 1 to 7 of the present application. However, the specific surface area and porosity of the fixing materials in Comparative Examples 2 to 4, and the fixing materials in Comparative Examples 2 and 3 are not significantly different from those of the fixing materials in the corresponding examples; Comparative Example 3 does not deposit a nano-conductive diamond mesoporous layer, and the specific surface area is significantly reduced.

[0157] It can be seen from this that the basalt porous ceramsite with specific parameters used in this application has a higher specific surface area and porosity, and after depositing the nano-conductive diamond mesoporous layer, the specific surface area can be further significantly improved.

[0158] Degradation experiment

[0159] Processing object preparation:

[0160] This experiment used simulated oily wastewater and polluted lake sediment as treatment objects. The simulated oily wastewater with COD of 1500mg / L was prepared with salad oil and tap water; the sediment of a polluted lake was tested and found to have a water content of 79% and a COD of 1224.6mg / L.

[0161] Compound bacterial solution configuration:

[0162] The fixed bacteria used in this experiment were a composite bacteria composed of Candida tropicalis, Candida parapsilosis, Bacillus licheniformis and Bacillus subtilis, which were prepared into a composite bacterial liquid. The number of viable cells of Candida tropicalis, Candida parapsilosis, Bacillus licheniformis and Bacillus subtilis in the composite bacterial liquid was 6×10 8 Pieces / mL.

[0163] Composite bacterial inoculation:

[0164] Take 100g of each of the fixing materials of Examples 1 to 12 of the present application and the fixing materials of Comparative Examples 1 to 6, and divide them into 18 groups, 2 portions in each group, and 50g in each portion. Inoculate the composite bacterial solution into the fixing material by dripping and adsorption, and drip 50mL of the composite bacterial solution to each fixing material. Finally, 16 groups, a total of 32 portions of fixed materials inoculated and fixed with composite bacteria, were obtained.

[0165] Experimental process:

[0166] The simulated oily sewage and polluted lake sediment were divided into 19 groups, each with 2L; the 18 groups of fixed materials for inoculation and fixation of composite bacteria were added to 18 groups of simulated oily sewage and 18 groups of polluted lake sediment, and each group added 1 fixed material for inoculation and fixation of composite bacteria to obtain 18 groups of simulated oily sewage samples and 18 groups of polluted lake sediment samples; 1 group of simulated oily sewage and 1 group of polluted lake sediment were added with composite bacteria solution, 50mL was added to each group, and 1 group of sewage control samples and 1 group of sediment control samples were obtained; after 48 hours, the COD value of each group of samples was detected, and the COD removal rate was calculated. The results are shown in Table 3 below. The calculation formula is: COD removal rate = (initial COD-final COD) / initial COD×100%.

[0167] Table 3 Degradation test results

[0168]

[0169] From the data in Table 3, it can be seen that the fixed materials of Examples 1 to 12 of the present application, after fixing the composite bacteria, have significantly better treatment capabilities for oily wastewater and polluted sediment than the fixed materials of Comparative Examples 1 to 6, and are much better than the free bacteria in the control group. From the data in Table 3, it can also be seen that the fixed materials of Examples 6 and 7 of the present application, after fixing the composite bacteria, have better treatment capabilities for oily wastewater and polluted sediment than the fixed materials of Examples 4 and 5, and are even better than the fixed materials of Examples 1 to 3.

[0170] It can be seen from this that, under the premise of the same nano-conductive diamond mesoporous layer, in the nano-gold layer, the smaller the nano-gold particle size, the thicker the coating thickness, and the thicker the coating of the nano-iron tetroxide layer, the better the performance and efficiency of catalytic degradation and catalytic oxidation of organic pollutants, and thus it can provide a more suitable growth environment for microorganisms, and is more conducive to the proliferation of microorganisms, thereby further improving the efficiency of biological treatment. In addition, in the nano-conductive diamond mesoporous layer, the particle size of the nano-conductive diamond grains is 120~150nm. The formed nano-conductive diamond mesoporous layer has a larger specific surface area under the premise of consistent thickness, and the fixed material has a better treatment effect on pollutants.

[0171] It can also be seen from the data in Table 3 that after the composite bacteria are fixed in the fixing materials of Examples 8 to 12 of the present application, the treatment capacity of oily wastewater and polluted sludge is significantly better than that of the fixing materials of Examples 1 to 7, and the fixing material of Example 12 has the best performance. It can be seen that the use of the specific basalt porous ceramsite of the present application has a larger specific surface area, is more conducive to catalytic degradation and catalytic oxidation of organic pollutants, and has a better treatment effect on pollutants.

[0172] It can also be seen from the data in Table 3 that after the fixed material of Example 12 of the present application fixes the composite bacteria, the treatment capacity of oily wastewater and polluted sediment is better than that of the fixed materials of Comparative Examples 2 to 4, and the fixed material of Comparative Example 2 is significantly better than that of the fixed materials of Comparative Examples 3 and 4. It can be seen from this that after the loss of nano-iron tetroxide, although the specific surface area of ​​the fixed material will increase slightly, the catalytic degradation effect of pollutants will decrease; and after the loss of the nano-conductive diamond mesoporous layer, not only the specific surface area of ​​the fixed material will decrease, but the catalytic degradation effect of pollutants will decrease more significantly; and relative to the combination of nano-iron tetroxide and nano-conductive diamond, the nano-gold catalyst and nano-conductive diamond have a better catalytic degradation effect on pollutants. The composite nanolayer formed by the three nano-components has a very obvious improvement in the catalytic degradation effect of pollutants compared to the nano-composite layer formed by the two nano-components.

[0173] Microbial protection verification experiment

[0174] This experiment uses an indirect method to simulate the immobilization of materials in toxic wastewater to verify its protective effect on immobilized microorganisms.

[0175] Processing object preparation:

[0176] This experiment used simulated oily wastewater and polluted lake sediment as treatment objects. Salad oil and tap water were used to prepare simulated oily wastewater with a COD of 1500 mg / L, and then p-nitrophenol was added to the wastewater until the p-nitrophenol concentration reached 50 mg / L to obtain toxic wastewater for the experiment.

[0177] Compound bacterial solution configuration:

[0178] The fixed bacteria used in this experiment were a composite bacteria composed of Candida tropicalis, Candida parapsilosis, Bacillus licheniformis and Bacillus subtilis, which were prepared into a composite bacterial liquid. The number of viable cells of Candida tropicalis, Candida parapsilosis, Bacillus licheniformis and Bacillus subtilis in the composite bacterial liquid was 6×10 8 Pieces / mL.

[0179] Composite bacterial inoculation:

[0180] Take 100g of the fixing material of Example 1 of the present application and 100g of the fixing materials of Comparative Examples 1 to 6 respectively, and divide them into 7 groups. The composite bacterial solution is inoculated into the fixing material by dripping and adsorption. For each fixing material, 50mL of the composite bacterial solution is dripped. Finally, 7 groups of fixing materials inoculated and fixed with composite bacteria are obtained. Take 100g of the basalt porous ceramsite carrier prepared in Preparation Example 4, inoculate the composite bacterial solution into the fixing material by dripping and adsorption, and drip 50mL of the composite bacterial solution as a blank control fixing material.

[0181] Experimental process:

[0182] Take 8 portions of experimental toxic sewage, each with 2L, and divide them into 8 groups; add the 7 groups of fixed materials for inoculation and fixed composite bacteria, as well as the blank control fixed materials, into the 8 groups of experimental toxic sewage respectively. After 2 hours, take samples to detect the COD value of each group of samples, and calculate the COD removal rate; remove the fixed materials from the 8 groups of samples, replace them with new experimental toxic sewage, repeat the above operation once, and the experimental results are shown in Table 4.

[0183] Table 4 Microbial protection verification test results

[0184]

[0185] It can be seen from the data in Table 4 that the fixed material of Example 1 of the present application and the fixed material of Comparative Example 6, after inoculation with composite bacteria, the COD removal rate of the second sewage treatment is improved compared with the COD removal rate of the first sewage treatment; while the fixed materials of Comparative Examples 1 to 4 and the fixed materials of the blank control, after inoculation with composite bacteria, the COD removal rate of the second sewage treatment is significantly reduced compared with the COD removal rate of the first sewage treatment; the fixed material of Comparative Example 5, after inoculation with composite bacteria, the COD removal rate of the second sewage treatment is not particularly significantly changed compared with the COD removal rate of the first sewage treatment. Among them, the fixed material of Comparative Example 1 and the fixed material of the blank control have almost no treatment capacity during the second sewage treatment.

[0186] It can be seen that the fixed materials of comparative examples 2 to 5 cannot provide a good protective effect on microorganisms. In toxic sewage, the inoculated microorganisms cannot proliferate well, so the sewage treatment capacity will be reduced due to the length of time they stay in toxic sewage. The fixed material of Example 1 of the present application can provide a good protective effect on microorganisms. The catalytic and degradation effects of the composite nanolayer can provide a good microenvironment for the inoculated microorganisms, so that the microorganisms can effectively proliferate in toxic sewage, so the sewage treatment capacity will increase with time. However, the fixed materials of comparative example 1 and the blank control cannot provide a protective effect on microorganisms. In toxic sewage, after a certain period of time, the inoculated microorganisms almost all die, so there is almost no treatment capacity during the second sewage treatment. It can be seen that the fixed material of the present application can provide effective protection for microorganisms and can make fixed microorganisms grow and proliferate in toxic sewage.

[0187] Microbial affinity test

[0188] Experimental sample preparation:

[0189] Two basalt plates with a size of 5×5×0.5 cm and a porosity of less than 10% were fired; one of the basalt plates was taken, and a composite nanolayer with substantially the same size was deposited on the surface thereof according to the preparation operation of Example 1 to obtain an experimental plate of sample 1; the other basalt plate was used as an experimental plate of sample 2.

[0190] Alumina ceramic plates with a size of 5×5×0.5 cm were fired as experimental plates for control samples, and commercially available glass culture dishes were used as blank controls.

[0191] Brushing of culture medium:

[0192] The Bacillus solid basic culture medium produced by Shanghai Guandao Bioengineering Co., Ltd. was selected, and a layer of 5 mm thick Bacillus solid basic culture medium was evenly applied on the surface of sample 1, sample 2, control sample and blank control.

[0193] Culture inoculation and cultivation:

[0194] Bacillus subtilis was selected as the culture bacteria. About 1×10 5 Then, the inoculated samples 1, 2, control samples and blank control were placed in a constant temperature incubator at 37°C for 8 hours.

[0195] Results test:

[0196] The proliferation rate of Bacillus subtilis on the surface of sample 1, sample 2, control sample and blank control was detected, and the results are shown in Table 5.

[0197] Table 5 Results of microbial affinity test

[0198]

[0199] It can be seen from the data in Table 5 that the proliferation rate of Bacillus subtilis on the basalt plate and the basalt plate with a composite nanolayer is slightly higher than that on the ceramic plate and the glass culture dish; there is no obvious difference in the proliferation rate of Bacillus subtilis between the basalt plate and the basalt plate with a composite nanolayer.

[0200] It can be seen that the fixing material of the present application, which is a composite nano-layer attached to the surface of basalt, has a better affinity to fungi and can promote the proliferation of microorganisms.

[0201] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A microorganism fixing material for treating polluted water, characterized in that: It includes a basalt porous ceramsite carrier, the particle size of the basalt porous ceramsite carrier is not greater than 10mm, and the specific surface area is not less than 10m 2 / g, and a porosity of not less than 70%; a composite nanolayer is arranged on the surface and in the pores of the basalt porous ceramsite carrier, the components of the composite nanolayer include nano-conductive diamond, nano-gold and nano-ferroferric oxide, the thickness of the composite nanolayer is not more than 800nm, and the preparation method of the composite nanolayer comprises the following steps: S1, preparing basalt porous ceramsite carrier; S2, placing the basalt porous ceramsite carrier obtained in step S1 in a ferric hydroxide colloidal solution, ultrasonically treating it for 15 to 30 minutes, taking it out, drying it, and then heating it at a temperature of 100 to 120° C. for more than 1 hour to obtain a ceramsite carrier with nano-iron tetroxide attached thereto; S3, placing the ceramsite carrier with nano-iron tetroxide obtained in step S2 in a mixed solution of sodium citrate and chloroauric acid, ultrasonically treating for 15 to 30 minutes, and then boiling for 15 to 20 minutes, taking out, washing, and drying to obtain the ceramsite carrier with nano-gold; S4, placing the ceramsite carrier with nano-gold obtained in step S3 in a nano-conductive diamond suspension, ultrasonically treating for 15 to 30 minutes, and then taking it out and drying it to obtain a porous ceramsite carrier with nano-conductive diamonds attached; S5. Using chemical vapor deposition, a nano-conductive diamond mesoporous layer is deposited on the surface and pores of the porous ceramsite carrier with nano-conductive diamonds attached thereto obtained in step S4, so as to obtain a microorganism fixing material for treating polluted water bodies.

2. The microorganism immobilization material for treating polluted water according to claim 1, characterized in that: The raw material components of the basalt porous ceramsite carrier include, by weight, 20-40 parts of porous basalt powder, 14-20 parts of attapulgite, 10-20 parts of alumina powder, 24-30 parts of pore formers, and 12-18 parts of adhesives.

3. The microorganism immobilization material for treating polluted water according to claim 2, characterized in that: The pore-forming agent is ammonium bicarbonate powder, and the adhesive is phenolic resin binder.

4. The microorganism immobilization material for treating polluted water according to claim 3, characterized in that: The particle sizes of the porous basalt powder, attapulgite and alumina powder are 50-100 μm, and the particle size of the ammonium bicarbonate powder is 400-500 μm.

5. The microorganism immobilization material for treating polluted water according to claim 1, characterized in that: The particle size of each component of the composite nanolayer is no greater than 200 nm.

6. The method for preparing a microorganism immobilization material for treating polluted water according to claim 1, characterized in that: The step S1 comprises the following steps: S1-1, fully mixing the raw material components of the basalt porous ceramsite carrier to prepare a slurry; S1-2, placing the slurry obtained in step S1-1 in a mixing and granulating machine to form ceramsite particles of target particle size; S1-3, heating the ceramsite green body particles obtained in step S1-2 to 200-240°C in a vacuum furnace, keeping the temperature for 30-60 minutes, then heating to 960-980°C, sintering at high temperature, and air cooling to room temperature to obtain a basalt porous ceramsite carrier.

7. The method for preparing a microorganism immobilization material for treating polluted water according to claim 6, characterized in that: In the mixed solution of sodium citrate and chloroauric acid, the mass fraction of sodium citrate is 0.1-0.15%, and the mass fraction of chloroauric acid is 0.15-0.2%.

8. The method for preparing a microorganism immobilization material for treating polluted water according to claim 6, characterized in that: In the step S4, the nano-conductive diamond suspension is an anhydrous ethanol suspension of nano-conductive diamond, and the mass fraction of nano-conductive diamond is 10-15%.

9. Use of the microorganism immobilization material for treating polluted water bodies as claimed in any one of claims 1 to 5 in the field of sediment purification and restoration of natural water bodies.

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