Soil organic pollutant degradation material containing microorganisms as well as preparation method and application of soil organic pollutant degradation material

Abstract

The invention relates to the field of soil organic pollutant degradation materials, in particular to a soil organic pollutant degradation material containing microorganisms as well as a preparation method and application thereof, and is used for solving the problems that an existing soil organic pollutant remediation method is complex in operation, low in organic pollutant degradation efficiency, poor in degradation effect and difficult to meet actual application requirements. According to the soil organic pollutant degradation material, the synergistic effect of the complex microbial inoculant-loaded doped biochar, the composite persulfate and the metal-loaded doped biochar is utilized, efficient degradation of organic pollutants in soil is achieved, remediation of polluted soil is achieved, and the soil organic pollutant degradation material is friendly to the ecological environment of the soil and beneficial to sustainable utilization of the soil; the preparation method is simple in process, the required raw materials are wide in source, low in price and suitable for large-scale production and application, and the prepared soil organic pollutant degradation material is suitable for different types of polluted soil and wide in application range.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of soil organic pollutant degradation materials, in particular to a soil organic pollutant degradation material containing microorganisms, a preparation method and application thereof. BACKGROUND

[0002] With the rapid development of industrialization and urbanization, the problem of soil organic pollutant pollution is becoming increasingly serious. Organic pollutants in soil, such as polycyclic aromatic hydrocarbons, pesticides, and petroleum hydrocarbons, have characteristics such as high toxicity, difficulty in degradation, and easy accumulation, which pose a serious threat to the ecological environment and human health.

[0003] Traditional soil organic pollutant remediation methods, such as physical remediation (including thermal desorption, gas-phase extraction, etc.) and chemical remediation (such as oxidation-reduction, leaching, etc.), can reduce pollutant concentration to some extent, but have problems such as high cost, complex operation, and easy secondary pollution. Microbial remediation technology, as a green, economic, and sustainable remediation method, has attracted widespread attention. Microorganisms can utilize organic pollutants as carbon and energy sources, and through their metabolic activities, they can degrade them into harmless carbon dioxide and water. However, the complexity of the soil environment and the difficulty of degrading organic pollutants limit the efficiency and effectiveness of microbial remediation.

[0004] Therefore, it is of great practical significance to develop a soil organic pollutant degradation material containing microorganisms, a preparation method and application thereof. SUMMARY

[0005] In order to overcome the above technical problems, the purpose of the present application is to provide a soil organic pollutant degradation material containing microorganisms, a preparation method and application thereof, which solves the problem that the existing soil organic pollutant remediation method is complex to operate, has low organic pollutant degradation efficiency and poor degradation effect, and cannot meet the needs of actual application.

[0006] The purpose of the present application can be achieved by the following technical solutions: The soil organic pollutant degradation material containing microorganisms comprises the following components by weight: 40-50 parts of composite microbial agent loaded doped biochar, 25-33 parts of metal loaded doped biochar, 11-19 parts of composite persulfate, 3-7 parts of surfactant, 2-6 parts of sodium carboxymethyl cellulose, 1-3 parts of superphosphate, 1-3 parts of sodium citrate, and 2-4 parts of calcium peroxide; The composite microbial agent loaded doped biochar is prepared by the following steps: Step a1: inoculate the composite microbial agent into LB culture medium, and culture at 30-35°C and 120-180 r / min until the logarithmic growth phase, then centrifuge and dilute with physiological saline to 109 -10 10 CFU / mL of complex microbial bacteria suspension; Step a2: the doped biochar, the complex microbial bacteria suspension is added to the three-necked flask equipped with a stirrer, a thermometer, and is stirred at a temperature of 25-30℃ and a stirring rate of 200-300r / min for 20-30h, after the reaction is completed, the reaction product is centrifuged, the precipitate is washed with distilled water for 2-3 times, and then vacuum freeze-dried to obtain the complex microbial agent loaded doped biochar.

[0007] As a further scheme of the application: the use amount ratio of the complex microbial agent and the LB culture medium in step a1 is 0.5-1g:10g.

[0008] As a further scheme of the application: the complex microbial agent in step a1 is a mixture of Streptomyces, Pseudomonas aeruginosa, Klebsiella oxytoca, Bacillus subtilis and Acinetobacter in equal mass ratio.

[0009] As a further scheme of the application: the use amount ratio of the doped biochar and the complex microbial bacteria suspension in step a2 is 1g:10-15mL.

[0010] As a further scheme of the application: the metal-loaded doped biochar is prepared by the following steps: Copper nitrate trihydrate, cobalt nitrate hexahydrate, iron nitrate nonahydrate and deionized water are added to a three-necked flask equipped with a stirrer and a thermometer, and stirred at a temperature of 25-30℃ and a stirring rate of 200-300r / min for 30-50min, then the doped biochar is added and stirred for 20-30min, then the temperature is increased to 80-85℃ and the stirring is continued for 2-3h, after the reaction is completed, the reaction product is cooled to room temperature, then centrifuged, and the precipitate is washed with anhydrous ethanol and distilled water for 2-3 times, then placed in a vacuum drying oven and dried at a temperature of 80-85℃ for 2-3h, then placed in a tube furnace and heated to 500-550℃ at a heating rate of 8-10℃ / min, and then calcined at a constant temperature for 1-2h under nitrogen protection, and then cooled in the furnace to obtain the metal-loaded doped biochar.

[0011] As a further scheme of the application: the use amount ratio of copper nitrate trihydrate, cobalt nitrate hexahydrate, iron nitrate nonahydrate, deionized water and doped biochar is 10mmol:10-20mmol:30-40mmol:200-220mL:10g.

[0012] As a further scheme of the application: the doped biochar is prepared by the following steps: Step b1: rice straw powder is soaked in hydrochloric acid solution for 20-30h, then vacuum filtration is carried out, the filter cake is washed with distilled water for 2-3 times, then placed in a vacuum drying oven and dried at a temperature of 80-85℃ for 4-5h, then placed in a tube furnace, heated to 700-750℃ at a heating rate of 8-10℃ / min, and nitrogen is introduced to protect the constant temperature calcination for 2-3h, then cooled with the furnace, and the straw biochar is obtained; Step b2: the straw biochar, dopant and deionized water are added to a three-necked flask equipped with a stirrer and a thermometer, stirred at a temperature of 25-30℃ and a stirring rate of 200-300r / min for 30-50min, then placed in a vacuum drying oven and dried at a temperature of 80-85℃ for 4-5h, then placed in a tube furnace, heated to 800-850℃ at a heating rate of 5-7℃ / min, and nitrogen is introduced to protect the constant temperature calcination for 1-2h, then cooled with the furnace and washed with anhydrous ethanol and distilled water for 2-3 times in turn, then placed in a vacuum drying oven and dried at a temperature of 80-85℃ for 2-3h, and the doped biochar is obtained.

[0013] As a further scheme of the application: the use amount ratio of the rice straw powder and the hydrochloric acid solution in step b1 is 5g:50-60mL.

[0014] As a further scheme of the application: the mass fraction of the hydrochloric acid solution in step b1 is 5-10%.

[0015] As a further scheme of the application: the use amount ratio of the straw biochar, the dopant and the deionized water in step b2 is 5g:3-9g:70-80mL.

[0016] As a further scheme of the application: the dopant in step b2 is a mixture of thiourea, boric acid and potassium hydroxide in a mass ratio of 1-1.5:2-2.2:4-5.

[0017] As a further scheme of the application: the preparation method of the soil organic pollutant degradation material containing microorganisms comprises the following steps: Step one: 40-50 parts of composite microbial agent loaded doped biochar, 25-33 parts of metal loaded doped biochar, 11-19 parts of composite persulfate, 3-7 parts of surfactant, 2-6 parts of sodium carboxymethyl cellulose, 1-3 parts of superphosphate, 1-3 parts of sodium citrate and 2-4 parts of calcium peroxide are weighed according to the weight parts, and prepared for use; Step two: the composite microbial inoculant, metal-doped biochar, composite persulfate, surfactant, sodium carboxymethyl cellulose, superphosphate, sodium citrate and calcium peroxide are added into a mixer, stirred and mixed at a temperature of 25-30 DEG C and a stirring speed of 600-1200 r / min for 20-40 min to obtain the soil organic pollutant degradation material containing microorganisms.

[0018] As a further scheme of the present application: the composite persulfate is a mixture of sodium persulfate and potassium monopersulfate in an equal mass ratio.

[0019] As a further scheme of the present application: the surfactant is a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 2-3:1.

[0020] As a further scheme of the present application: the soil organic pollutant degradation material containing microorganisms is applied in the degradation treatment of organic pollutants in contaminated soil.

[0021] The present application has the following advantages: The soil organic pollutant degradation material containing microorganisms, preparation method and application of the present application can realize the repair of contaminated soil, are friendly to the ecological environment of soil, are conducive to the sustainable use of soil, can degrade a variety of types of soil organic pollutants, are suitable for different types of contaminated soil, and have a wide range of applications.

[0022] In the process of preparing the soil organic pollutant degradation material, a doped biochar is first prepared. Rice straw powder is used as raw material to remove impurities thereon by hydrochloric acid solution, and straw biochar is formed by calcination. Then, the straw biochar is doped by using a dopant. Thiourea provides sulfur and nitrogen elements, boric acid provides boron element, and potassium hydroxide performs activation and hole expansion. After calcination, the doped biochar has rich pore structure and large specific surface area, and contains sulfur, nitrogen and boron elements. The doped biochar can efficiently adsorb organic pollutants in contaminated soil, improve the contact opportunity of organic pollutants and degradation material, and provide a good living environment for microorganisms. In combination with calcium peroxide, the doped biochar can provide sufficient oxygen for microorganisms, facilitate the reproduction of microorganisms, and increase the surface functional groups and surface defects of the biochar by doping sulfur, nitrogen and boron elements, thereby improving the catalytic activation ability of the biochar and activating persulfate to realize efficient degradation of organic pollutants.

[0023] In the process of preparing the soil organic pollutant degradation material, a doped biochar is first prepared. Rice straw powder is used as raw material to remove impurities thereon by hydrochloric acid solution, and straw biochar is formed by calcination. Then, the straw biochar is doped by using a dopant. Thiourea provides sulfur and nitrogen elements, boric acid provides boron element, and potassium hydroxide performs activation and hole expansion. After calcination, the doped biochar has rich pore structure and large specific surface area, and contains sulfur, nitrogen and boron elements. The doped biochar can efficiently adsorb organic pollutants in contaminated soil, improve the contact opportunity of organic pollutants and degradation material, and provide a good living environment for microorganisms. In combination with calcium peroxide, the doped biochar can provide sufficient oxygen for microorganisms, facilitate the reproduction of microorganisms, and increase the surface functional groups and surface defects of the biochar by doping sulfur, nitrogen and boron elements, thereby improving the catalytic activation ability of the biochar and activating persulfate to realize efficient degradation of organic pollutants.

[0024] In the process of preparing the soil organic pollutant degradation material, a doped biochar is first prepared. Rice straw powder is used as raw material to remove impurities thereon by hydrochloric acid solution, and straw biochar is formed by calcination. Then, the straw biochar is doped by using a dopant. Thiourea provides sulfur and nitrogen elements, boric acid provides boron element, and potassium hydroxide performs activation and hole expansion. After calcination, the doped biochar has rich pore structure and large specific surface area, and contains sulfur, nitrogen and boron elements. The doped biochar can efficiently adsorb organic pollutants in contaminated soil, improve the contact opportunity of organic pollutants and degradation material, and provide a good living environment for microorganisms. In combination with calcium peroxide, the doped biochar can provide sufficient oxygen for microorganisms, facilitate the reproduction of microorganisms, and increase the surface functional groups and surface defects of the biochar by doping sulfur, nitrogen and boron elements, thereby improving the catalytic activation ability of the biochar and activating persulfate to realize efficient degradation of organic pollutants. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application. Embodiment 1

[0026] The present embodiment is a preparation method of a soil organic pollutant degradation material containing microorganisms, comprising the following steps: Step S1: 5 g of rice straw powder was soaked in 50 mL of 5% hydrochloric acid solution for 20 h, then vacuum filtered, the filter cake was washed with distilled water for 2 times, then placed in a vacuum drying oven at a temperature of 80℃ for 4 h, then placed in a tube furnace, heated to 700℃ at a heating rate of 8℃ / min, and nitrogen was introduced to protect the constant temperature calcination for 2 h, then cooled with the furnace, to obtain straw biochar; Step S2: 5 g of straw biochar, 3 g of doped agent composed of thiourea, boric acid and potassium hydroxide in a mass ratio of 1:2:4, and 70 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, stirred at a temperature of 25℃ and a stirring rate of 200 r / min for 30 min, then placed in a vacuum drying oven at a temperature of 80℃ for 4 h, then placed in a tube furnace, heated to 800℃ at a heating rate of 5℃ / min, and nitrogen was introduced to protect the constant temperature calcination for 1 h, then cooled with the furnace and washed with anhydrous ethanol and distilled water for 2 times, then placed in a vacuum drying oven at a temperature of 80℃ for 2 h, to obtain doped biochar; Step S3: 0.5 g of complex microbial agent was inoculated in 10 g of LB medium, cultured at 30℃ and 120 r / min to the logarithmic growth phase, then centrifuged, and diluted with physiological saline to 10 9 CFU / mL of complex microbial suspension; the complex microbial agent is a mixture of Streptomyces, Pseudomonas aeruginosa, Klebsiella oxytoca, Bacillus subtilis and Acinetobacter in equal mass ratio; Step S4: 1 g of doped biochar and 10 mL of complex microbial suspension were added to a three-necked flask equipped with a stirrer and a thermometer, stirred at a temperature of 25℃ and a stirring rate of 200 r / min for 20 h, then the reaction product was centrifuged, the precipitate was washed with distilled water for 2 times, then vacuum freeze-dried, to obtain complex microbial agent loaded doped biochar; Step S5: 10 mmol of copper nitrate trihydrate, 10 mmol of cobalt nitrate hexahydrate, 30 mmol of ferric nitrate nonahydrate and 200 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, and stirred at a temperature of 25℃ and a stirring rate of 200 r / min for 30 min, then 10 g of the doped biochar was added and stirred for 20 min, and then the temperature was raised to 80℃ and the stirring was continued for 2 h. After the reaction was completed, the reaction product was cooled to room temperature, then centrifuged, and the precipitate was washed with anhydrous ethanol and distilled water for 2 times, respectively, then placed in a vacuum drying oven and dried at a temperature of 80℃ for 2 h, then placed in a tube furnace and heated to 500℃ at a heating rate of 8℃ / min, and then nitrogen was introduced to protect the constant temperature calcination for 1 h, then the furnace was cooled, and the metal-loaded doped biochar was obtained; Step S6: The composite microbial agent-loaded doped biochar 40 parts, the metal-loaded doped biochar 25 parts, the composite persulfate 11 parts, the surfactant 3 parts, the sodium carboxymethyl cellulose 2 parts, the calcium superphosphate 1 part, the sodium citrate 1 part and the calcium peroxide 2 parts were weighed according to the weight parts, and were ready for use. The composite persulfate is a mixture of sodium persulfate and monopersulfate hydrogen potassium in an equal mass ratio. The surfactant is a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 2:1. Step S7: The composite microbial agent-loaded doped biochar, the metal-loaded doped biochar, the composite persulfate, the surfactant, the sodium carboxymethyl cellulose, the calcium superphosphate, the sodium citrate and the calcium peroxide were added to a mixer and stirred and mixed at a temperature of 25℃ and a stirring rate of 600 r / min for 20 min to obtain the soil organic pollutant degradation material containing microorganisms. Example 2

[0027] The present embodiment is a preparation method of a soil organic pollutant degradation material containing microorganisms, comprising the following steps: Step S1: 5 g of rice straw powder was soaked in 55 mL of 8% hydrochloric acid solution for 25 h, then vacuum filtered, and the filter cake was washed with distilled water for 2 times, then placed in a vacuum drying oven and dried at a temperature of 82℃ for 4.5 h, then placed in a tube furnace and heated to 725℃ at a heating rate of 9℃ / min, and then nitrogen was introduced to protect the constant temperature calcination for 2.5 h, then the furnace was cooled, and the straw biochar was obtained. Step S2: 5 g of straw biochar, 6 g of doped agent of thiourea, boric acid and potassium hydroxide in a mass ratio of 1.2:2.1:4.5 and 75 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, stirred at a temperature of 28℃ and a stirring rate of 250 r / min for 40 min, then placed in a vacuum drying oven and dried at a temperature of 82℃ for 4.5 h, then placed in a tube furnace, heated to 825℃ at a heating rate of 6℃ / min, and calcined at a constant temperature for 1.5 h under nitrogen protection, then cooled with the furnace and washed with anhydrous ethanol and distilled water twice, then placed in a vacuum drying oven and dried at a temperature of 82℃ for 2.5 h, to obtain a doped biochar; Step S3: 0.8 g of a complex microbial agent was inoculated into 10 g of LB medium and cultured at 32℃ and 150 r / min until the logarithmic growth phase, then centrifuged and diluted with physiological saline to 10 9 CFU / mL of a complex microbial suspension; the complex microbial agent is a mixture of Streptomyces, Pseudomonas aeruginosa, Klebsiella oxytoca, Bacillus subtilis and Acinetobacter in an equal mass ratio; Step S4: 1 g of doped biochar and 12 mL of a complex microbial suspension were added to a three-necked flask equipped with a stirrer and a thermometer, stirred at a temperature of 28℃ and a stirring rate of 250 r / min for 25 h, then the reaction product was centrifuged, the precipitate was washed with distilled water twice, and then vacuum freeze-dried to obtain a complex microbial agent loaded doped biochar; Step S5: 10 mmol of copper nitrate trihydrate, 15 mmol of cobalt nitrate hexahydrate, 35 mmol of iron nitrate nonahydrate and 210 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, stirred at a temperature of 28℃ and a stirring rate of 250 r / min for 40 min, then 10 g of doped biochar was added and stirred for 25 min, then heated to 82℃ and stirred for 2.5 h, then the reaction product was cooled to room temperature, then centrifuged, the precipitate was washed with anhydrous ethanol and distilled water twice, then placed in a vacuum drying oven and dried at a temperature of 82℃ for 2.5 h, then placed in a tube furnace and heated to 525℃ at a heating rate of 9℃ / min, and calcined at a constant temperature for 1.5 h under nitrogen protection, then cooled with the furnace to obtain a metal-loaded doped biochar; Step S6: 45 parts of composite microbial agent loaded doped biochar, 29 parts of metal loaded doped biochar, 15 parts of composite persulfate, 5 parts of surfactant, 4 parts of sodium carboxymethyl cellulose, 2 parts of calcium superphosphate, 2 parts of sodium citrate and 3 parts of calcium peroxide were weighed according to the weight parts, ready for use; wherein the composite persulfate is a mixture of sodium persulfate and monopersulfate hydrogen potassium in equal mass ratio; the surfactant is a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 2.5:1; Step S7: the composite microbial agent loaded doped biochar, metal loaded doped biochar, composite persulfate, surfactant, sodium carboxymethyl cellulose, calcium superphosphate, sodium citrate and calcium peroxide were added to the mixer, stirred and mixed at a temperature of 28℃ and a stirring rate of 900r / min for 30min to obtain a soil organic pollutant degradation material containing microorganisms. Example 3

[0028] The present embodiment is a preparation method of a soil organic pollutant degradation material containing microorganisms, comprising the following steps: Step S1: 5g of rice straw powder was soaked in 60mL of 10% hydrochloric acid solution for 30h, then vacuum filtered, the filter cake was washed with distilled water for 3 times, then placed in a vacuum drying oven, dried at a temperature of 85℃ for 5h, then placed in a tube furnace, heated to 750℃ at a heating rate of 10℃ / min, and nitrogen was introduced to protect the constant temperature calcination for 3h, then cooled with the furnace, to obtain straw biochar; Step S2: 5g of straw biochar, 9g of doped agent mixed with thiourea, boric acid and potassium hydroxide in a mass ratio of 1.5:2.2:5, and 80mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, stirred at a temperature of 30℃ and a stirring rate of 300r / min for 50min, then placed in a vacuum drying oven, dried at a temperature of 85℃ for 5h, then placed in a tube furnace, heated to 850℃ at a heating rate of 7℃ / min, and nitrogen was introduced to protect the constant temperature calcination for 2h, then cooled with the furnace and washed with anhydrous ethanol and distilled water for 3 times, then placed in a vacuum drying oven, dried at a temperature of 85℃ for 3h, to obtain doped biochar; Step S3: 1g of composite microbial agent was inoculated in 10g of LB medium, cultured at 35℃ and 180r / min until the logarithmic growth phase, then centrifuged, and diluted with physiological saline to 10 10 CFU / mL of composite microbial suspension; the composite microbial agent is a mixture of Streptomyces, Pseudomonas aeruginosa, Klebsiella oxytoca, Bacillus subtilis and Acinetobacter in equal mass ratio; Step S4: 1 g of doped biochar and 15 mL of composite microbial bacteria suspension were added to a three-necked flask equipped with a stirrer and a thermometer, and stirred at 30℃ and 300 r / min for 30 h. After the reaction, the reaction product was centrifuged, the precipitate was washed with distilled water for 3 times, and then vacuum freeze-dried to obtain a composite microbial agent loaded doped biochar; Step S5: 10 mmol of copper nitrate trihydrate, 20 mmol of cobalt nitrate hexahydrate, 40 mmol of iron nitrate nonahydrate, and 220 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, and stirred at 30℃ and 300 r / min for 50 min. Then 10 g of doped biochar was added and stirred for another 30 min. Then the temperature was raised to 85℃ and the stirring was continued for 3 h. After the reaction, the reaction product was cooled to room temperature, then centrifuged, and the precipitate was washed with anhydrous ethanol and distilled water for 3 times, respectively. Then it was placed in a vacuum drying oven and dried at 85℃ for 3 h. Then it was placed in a tube furnace and heated to 550℃ at a heating rate of 10℃ / min, and then calcined at a constant temperature for 2 h under nitrogen protection. After that, the furnace was cooled down to obtain a metal-loaded doped biochar; Step S6: The composite microbial agent loaded doped biochar, the metal-loaded doped biochar, the composite persulfate, the surfactant, the carboxymethyl cellulose sodium, the calcium superphosphate, the sodium citrate, and the calcium peroxide were weighed according to the weight parts, and were prepared for use. The composite persulfate was a mixture of sodium persulfate and potassium monopersulfate in equal mass ratio. The surfactant was a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 3:1. Step S7: The composite microbial agent loaded doped biochar, the metal-loaded doped biochar, the composite persulfate, the surfactant, the carboxymethyl cellulose sodium, the calcium superphosphate, the sodium citrate, and the calcium peroxide were added to a mixer and stirred at 30℃ and 1200 r / min for 40 min to obtain a soil organic pollutant degradation material containing microorganisms.

[0029] Comparative Example 1 The present comparative example is a preparation method of a soil organic pollutant degradation material containing microorganisms, which comprises the following steps: Step S1: The composite persulfate, the surfactant, the carboxymethyl cellulose sodium, the calcium superphosphate, the sodium citrate, and the calcium peroxide were weighed according to the weight parts, and were prepared for use. The composite persulfate was a mixture of sodium persulfate and potassium monopersulfate in equal mass ratio. The surfactant was a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 3:1. Step S2: The composite persulfate, surfactant, sodium carboxymethyl cellulose, calcium superphosphate, sodium citrate and calcium peroxide were added to a mixer, stirred and mixed at a temperature of 30°C and a stirring rate of 1200 r / min for 40 min to obtain a soil organic pollutant degradation material containing microorganisms.

[0030] Comparative Example 2: The present comparative example is a preparation method of a soil organic pollutant degradation material containing microorganisms, comprising the following steps: Step S1: 5 g of rice straw powder was soaked in 60 mL of a 10% hydrochloric acid solution for 30 h, then vacuum filtered, the filter cake was washed with distilled water for 3 times, then placed in a vacuum drying oven and dried at a temperature of 85°C for 5 h, then placed in a tube furnace, heated to 750°C at a heating rate of 10°C / min, and nitrogen was introduced to protect the constant temperature calcination for 3 h, then cooled with the furnace, to obtain straw biochar; Step S2: 5 g of straw biochar, 9 g of doped agent of thiourea, boric acid and potassium hydroxide mixed in a mass ratio of 1.5:2.2:5, and 80 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, stirred and reacted at a temperature of 30°C and a stirring rate of 300 r / min for 50 min, then placed in a vacuum drying oven and dried at a temperature of 85°C for 5 h, then placed in a tube furnace, heated to 850°C at a heating rate of 7°C / min, and nitrogen was introduced to protect the constant temperature calcination for 2 h, then cooled with the furnace and washed with anhydrous ethanol and distilled water for 3 times, respectively, then placed in a vacuum drying oven and dried at a temperature of 85°C for 3 h, to obtain doped biochar; Step S3: The doped biochar 50 parts, composite persulfate 19 parts, surfactant 7 parts, sodium carboxymethyl cellulose 6 parts, calcium superphosphate 3 parts, sodium citrate 3 parts and calcium peroxide 4 parts were weighed according to the weight parts, and were prepared for use. The composite persulfate is a mixture of sodium persulfate and monopersulfate hydrogen potassium in an equal mass ratio. The surfactant is a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 3:1. Step S4: The doped biochar, composite persulfate, surfactant, sodium carboxymethyl cellulose, calcium superphosphate, sodium citrate and calcium peroxide were added to a mixer, stirred and mixed at a temperature of 30°C and a stirring rate of 1200 r / min for 40 min to obtain a soil organic pollutant degradation material containing microorganisms.

[0031] Comparative Example 3: The present comparative example is a preparation method of a soil organic pollutant degradation material containing microorganisms, comprising the following steps: Step S1: 5g of rice straw powder was soaked in 60mL of 10% hydrochloric acid solution for 30h, then vacuum filtration, the filter cake was washed with distilled water for 3 times, then placed in a vacuum drying oven, dried at 85℃ for 5h, then placed in a tube furnace, heated to 750℃ at a heating rate of 10℃ / min, and nitrogen was protected for constant temperature calcination for 3h, then furnace cooling, to obtain straw biochar; Step S2: 5g of straw biochar, 9g of doped agent of thiourea, boric acid and potassium hydroxide mixed in a mass ratio of 1.5:2.2:5, and 80mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, stirred at 30℃ and 300r / min for 50min, then placed in a vacuum drying oven, dried at 85℃ for 5h, then placed in a tube furnace, heated to 850℃ at a heating rate of 7℃ / min, and nitrogen was protected for constant temperature calcination for 2h, then cooled and washed with absolute ethanol and distilled water for 3 times, then placed in a vacuum drying oven, dried at 85℃ for 3h, to obtain doped biochar; Step S3: 1g of complex microbial agent was inoculated in 10g of LB medium, cultured at 35℃ and 180r / min to the logarithmic growth phase, then centrifuged, and diluted to 10 10 CFU / mL of complex microbial suspension with physiological saline; the complex microbial agent is a mixture of Streptomyces, Pseudomonas aeruginosa, Klebsiella oxytoca, Bacillus subtilis and Acinetobacter in equal mass ratio; Step S4: 1g of doped biochar and 15mL of complex microbial suspension were added to a three-necked flask equipped with a stirrer and a thermometer, stirred at 30℃ and 300r / min for 30h, then the reaction product was centrifuged, the precipitate was washed with distilled water for 3 times, then vacuum freeze-dried, to obtain complex microbial agent loaded doped biochar; Step S5: 50 parts of complex microbial agent loaded doped biochar, 19 parts of complex persulfate, 7 parts of surfactant, 6 parts of sodium carboxymethyl cellulose, 3 parts of calcium superphosphate, 3 parts of sodium citrate and 4 parts of calcium peroxide were weighed according to the weight parts, for standby use; wherein the complex persulfate is a mixture of sodium persulfate and monopersulfate in equal mass ratio; the surfactant is a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 3:1; Step S6: The composite microbial agent, the doped biochar, the composite persulfate, the surfactant, the sodium carboxymethyl cellulose, the calcium superphosphate, the sodium citrate and the calcium peroxide were added into a mixer, stirred and mixed at a temperature of 30°C and a stirring speed of 1200 r / min for 40 min to obtain a soil organic pollutant degradation material containing microorganisms.

[0032] Comparative Example 4 The present comparative example is a preparation method of a soil organic pollutant degradation material containing microorganisms, comprising the following steps: Step S1: 5 g of rice straw powder was soaked in 60 mL of a 10% hydrochloric acid solution for 30 h, then vacuum filtered, the filter cake was washed with distilled water for 3 times, then placed in a vacuum drying oven and dried at a temperature of 85°C for 5 h, then placed in a tube furnace, heated to 750°C at a heating rate of 10°C / min, and nitrogen was introduced to protect the constant temperature calcination for 3 h, then cooled with the furnace, to obtain straw biochar; Step S2: 5 g of straw biochar, 9 g of a doped agent composed of thiourea, boric acid and potassium hydroxide in a mass ratio of 1.5:2.2:5, and 80 mL of deionized water were added into a three-necked flask equipped with a stirrer and a thermometer, stirred and reacted at a temperature of 30°C and a stirring speed of 300 r / min for 50 min, then placed in a vacuum drying oven and dried at a temperature of 85°C for 5 h, then placed in a tube furnace, heated to 850°C at a heating rate of 7°C / min, and nitrogen was introduced to protect the constant temperature calcination for 2 h, then cooled with the furnace and washed with anhydrous ethanol and distilled water for 3 times, then placed in a vacuum drying oven and dried at a temperature of 85°C for 3 h, to obtain a doped biochar; Step S3: 10 mmol of copper nitrate trihydrate, 20 mmol of cobalt nitrate hexahydrate, 40 mmol of iron nitrate nonahydrate and 220 mL of deionized water were added into a three-necked flask equipped with a stirrer and a thermometer, stirred and reacted at a temperature of 30°C and a stirring speed of 300 r / min for 50 min, then 10 g of doped biochar was added and stirred for 30 min, then heated to 85°C and stirred for 3 h, after the reaction was completed, the reaction product was cooled to room temperature, then centrifuged, the precipitate was washed with anhydrous ethanol and distilled water for 3 times, then placed in a vacuum drying oven and dried at a temperature of 85°C for 3 h, then placed in a tube furnace, heated to 550°C at a heating rate of 10°C / min, and nitrogen was introduced to protect the constant temperature calcination for 2 h, then cooled with the furnace, to obtain a metal-loaded doped biochar; Step S4: 33 parts of metal-loaded doped biochar, 19 parts of composite persulfate, 7 parts of surfactant, 6 parts of sodium carboxymethyl cellulose, 3 parts of calcium superphosphate, 3 parts of sodium citrate, and 4 parts of calcium peroxide were weighed according to the weight parts and prepared for use; wherein the composite persulfate is a mixture of sodium persulfate and monopersulfate hydrogen potassium in an equal mass ratio; the surfactant is a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 3:1; Step S5: The metal-loaded doped biochar, the composite persulfate, the surfactant, the sodium carboxymethyl cellulose, the calcium superphosphate, the sodium citrate, and the calcium peroxide were added to a mixer and stirred and mixed at a temperature of 30°C and a stirring rate of 1200 r / min for 40 min to obtain a soil organic pollutant degradation material containing microorganisms.

[0033] Contaminated soil was taken from a contaminated area near an oil field, stones and branches were removed, and then crushed. The soil physical and chemical properties of the contaminated soil were detected, and the detection results are shown in the following table:

[0034] 7 parts of 1000g of contaminated soil were weighed into beakers, 50g of the soil organic pollutant degradation material containing microorganisms of Examples 1-3 and Comparative Examples 1-4 was added to the beakers, and 500mL of deionized water was added to the beakers, and stirred at a temperature of 25°C and a stirring rate of 60r / min for 24h. After that, the contaminated soil was placed in a well-ventilated place for 30d, and then the petroleum hydrocarbon content in the contaminated soil was measured, and the petroleum hydrocarbon degradation rate K was calculated, the calculation method was: K= (C0-C1) / C0x100%, wherein C0 was the petroleum hydrocarbon content of the untreated contaminated soil, C1 was the petroleum hydrocarbon content of the treated contaminated soil, and the measurement results are shown in the following table:

[0035] Referring to the data in the above table, according to the comparison between Examples 1-3 and Comparative Examples 1-4, it can be seen that the addition of composite microbial inoculum loaded doped biochar and metal-loaded doped biochar to the soil organic pollutant degradation material can significantly improve its organic matter degradation performance, so that the soil organic pollutant degradation material containing microorganisms of the present application has excellent organic matter degradation performance.

[0036] In the description of the specification, reference to terms "one embodiment", "an example", "a specific example" and so on is intended to indicate that a particular feature, structure, material or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. Descriptive expressions of the above terms in the specification do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0037] The above is only an example and illustration of the application, and those skilled in the art can make various modifications or supplements to the described specific embodiments or replace them with similar ways, as long as they do not deviate from the application or exceed the scope defined in the application.

Claims

1. A soil organic pollutant degradation material containing microorganisms, characterized in that, Includes the following components by weight: The compound microbial agent-loaded doped biochar contains 40-50 parts, metal-loaded doped biochar contains 25-33 parts, compound persulfate contains 11-19 parts, surfactant contains 3-7 parts, sodium carboxymethyl cellulose contains 2-6 parts, superphosphate contains 1-3 parts, sodium citrate contains 1-3 parts, and calcium peroxide contains 2-4 parts. The composite microbial agent-supported doped biochar is prepared by the following steps: Step a1: Inoculate the compound microbial agent into LB medium for culture, then centrifuge and dilute to obtain a compound microbial suspension; Step a2: Stir the doped biochar and the composite microbial suspension to react. After the reaction is complete, centrifuge the reaction product, wash the precipitate, and freeze-dry it under vacuum to obtain composite microbial agent-loaded doped biochar.

2. The soil organic pollutant degradation material containing microorganisms according to claim 1, characterized in that, The ratio of the compound microbial agent to LB culture medium in step a1 is 0.5-1g:10g; the compound microbial agent is a mixture of Streptomyces, Pseudomonas aeruginosa, Klebsiella pneumoniae, Bacillus subtilis and Acinetobacter in equal mass ratios.

3. The soil organic pollutant degradation material containing microorganisms according to claim 1, characterized in that, The ratio of the doped biochar and the composite microbial suspension used in step a2 is 1g:10-15mL.

4. The soil organic pollutant degradation material containing microorganisms according to claim 1, characterized in that, The metal-supported doped biochar was prepared by the following steps: Copper nitrate trihydrate, cobalt nitrate hexahydrate, ferric nitrate nonahydrate, and deionized water were stirred and reacted. Then, doped biochar was added and the reaction was continued with stirring. After the reaction was completed, the reaction product was cooled, centrifuged, and the precipitate was washed, dried, and then calcined at a constant temperature to obtain metal-loaded doped biochar.

5. The soil organic pollutant degradation material containing microorganisms according to claim 4, characterized in that, The ratio of copper nitrate trihydrate, cobalt nitrate hexahydrate, ferric nitrate nonahydrate, deionized water, and doped biochar is 10 mmol: 10-20 mmol: 30-40 mmol: 200-220 mL: 10 g.

6. The soil organic pollutant degradation material containing microorganisms according to claim 1, characterized in that, The doped biochar was prepared by the following steps: Step b1: Soak rice straw powder in hydrochloric acid solution, then vacuum filter, wash and dry the filter cake, and then calcine at a constant temperature to obtain straw biochar; Step b2: Stir the straw biochar, dopant and deionized water to react, then calcine at a constant temperature, then wash and dry to obtain doped biochar.

7. The soil organic pollutant degradation material containing microorganisms according to claim 6, characterized in that, In step b1, the ratio of rice straw powder to hydrochloric acid solution is 5g: 50-60mL; the mass fraction of the hydrochloric acid solution is 5-10%.

8. The soil organic pollutant degradation material containing microorganisms according to claim 6, characterized in that, In step b2, the ratio of straw biochar, dopant, and deionized water is 5g:3-9g:70-80mL; the dopant is a mixture of thiourea, boric acid, and potassium hydroxide in a mass ratio of 1-1.5:2-2.2:4-5.

9. A method for preparing soil organic pollutant degradation materials containing microorganisms, characterized in that, Includes the following steps: Step 1: Weigh out 40-50 parts of compound bacterial agent-supported doped biochar, 25-33 parts of metal-supported doped biochar, 11-19 parts of compound persulfate, 3-7 parts of surfactant, 2-6 parts of sodium carboxymethyl cellulose, 1-3 parts of superphosphate, 1-3 parts of sodium citrate, and 2-4 parts of calcium peroxide according to the following weight ratios, and set aside; wherein, the compound persulfate is a mixture of sodium persulfate and potassium monopersulfate in an equal mass ratio; the surfactant is a mixture of polysorbate 80 and sodium dodecyl sulfate in a mass ratio of 2-3:1; Step 2: Add the composite microbial agent-loaded doped biochar, metal-loaded doped biochar, composite persulfate, surfactant, sodium carboxymethyl cellulose, superphosphate, sodium citrate, and calcium peroxide into a mixer and mix for 20-40 minutes at a temperature of 25-30℃ and a stirring rate of 600-1200 r / min to obtain soil organic pollutant degradation material containing microorganisms.

10. The application of the soil organic pollutant degradation material containing microorganisms prepared by the method of preparation of soil organic pollutant degradation material containing microorganisms as described in claim 9 in the degradation treatment of organic pollutants in contaminated soil.

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