Phenolic soil pollution remediation material as well as preparation method and application thereof

Abstract

The invention discloses a phenolic soil pollution remediation material as well as a preparation method and application thereof. The preparation method comprises the following steps: firstly, uniformly mixing dried salix psammophila branch chippings and iron-containing sludge particles to prepare a mixed raw material; and placing the mixed raw material in a tubular furnace for anaerobic pyrolysis to prepare the phenolic soil pollution remediation material. The prepared phenol soil pollution remediation material is added into phenol-polluted soil to strengthen bioremediation of the phenol-polluted soil, the concentration of residual phenol and microbial communities in the soil are tested after bioremediation is completed, and the pollution remediation effect is evaluated. The iron-containing sludge discharged by a Fenton treatment unit for waste water in the waste paper papermaking industry and the waste salix psammophila biomass are subjected to co-pyrolysis, the prepared composite soil remediation material plays a role in enhancing remediation of the phenol-contaminated soil, and meanwhile the technical effects of low cost and pollution control with waste are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental protection, and in particular relates to a phenolic soil pollution remediation material and a preparation method and application thereof. Background Art

[0002] Phenolic compounds are widely used in various industries such as pharmaceuticals, petroleum, coatings, explosives, papermaking, wood and agricultural chemical manufacturing. According to the number of hydroxyl groups directly connected to the aromatic ring, phenolic compounds can be subdivided into monovalent, divalent and polyvalent phenols. Due to the ionization of phenolic hydroxyl groups, phenolic pollutants are usually acidic, corrosive and biotoxic. Phenols are protoplasmic poisons and are strictly regulated toxic organic pollutants worldwide. Phenol is the simplest and most typical phenolic compound. It is an important raw material for the production of various downstream products such as ketone alcohol oil, phenolic resin, caprolactam, bisphenol A, etc. With the increasing production of phenols, the environmental media pollution problems it brings are also increasingly concerned. Among them, soil is an environmental medium for the accumulation of pollutants that cannot be ignored. Soil environmental safety is closely related to life and health. Therefore, the soil environmental pollution problem caused by phenol needs to be solved urgently.

[0003] Soil is a natural reservoir of microorganisms. The remediation technology that promotes the degradation of organic pollutants by soil microorganisms through engineering technology is a pollution control technology that is both low-cost and environmentally friendly. It is a competitive and preferred measure for the remediation of phenol-contaminated soil. However, because phenol pollutants are biologically toxic, their toxic inhibition of microorganisms often leads to a slow remediation rate. In order to accelerate the bioremediation process, technologies such as adding nutrients and electron acceptors (such as oxygen) to contaminated media have emerged. Biochar materials prepared from agricultural biomass have multiple functions and wide application potential due to their unique structural characteristics (large specific surface area and porous structure) and surface functional groups (containing oxygen, nitrogen and sulfur functional groups). Adding biochar materials with certain functions to contaminated soil can stimulate the activity of indigenous microorganisms and accelerate the degradation of organic pollutants.

[0004] In recent years, the modification of biochar materials by adding oxygen-containing functional groups, acid modification, alkali modification and other technical means in order to obtain new materials with the function of accelerating soil pollution remediation has received attention. However, modification measures mean an increase in costs, which limits its application and promotion.

[0005] Biochar, with its good physical structure and rich specific surface area, has gradually become an emerging environmental remediation material and is widely used in environmental remediation and management. The raw materials for preparing biochar are widely available. Many agricultural and forestry wastes (such as straw, tamarisk and rice husks) and organic wastes (such as feces and sludge) can be used as raw materials for preparing biochar. Fenton is a common technology for deep treatment of wastewater in the waste paper and papermaking industry. The iron-containing sludge it discharges has the characteristics of high iron content (mainly in the form of Fe(OH)3 and Fe2O3) and low content of other common heavy metals (lower than the heavy metal limit for agricultural fertilizers specified in national standards). The iron-rich sludge contains high iron elements and biomass, and can be used to prepare iron mud-based carbon materials by pyrolysis, which has high potential for resource utilization. Chen Tianlai used iron-rich sludge as raw material and adopted the impregnation pyrolysis method to prepare a manganese-modified iron mud-based carbon material. The research results showed that the material can effectively reduce the concentration of heavy metals in the soil and increase the enzyme activity of the soil ([1] Chen Tianlai. Research on the remediation of cadmium and arsenic in water and soil environments using manganese-modified iron mud-based carbon materials [D]. Nanning Normal University, 2023.). In addition to heavy metal pollution, many studies have also analyzed the performance of iron-rich sludge biochar as an adsorbent for organic pollutants. For example, Lin Taicheng et al. used iron-rich sludge as raw material and prepared iron-rich sludge-based biochar at a pyrolysis temperature of 900°C for the adsorption of tetracycline in water ([2] Lin Taicheng, Lin Jinhua, Li Yihua, et al. Study on the adsorption performance of iron-rich sludge-derived magnetic biochar on tetracycline [J]. Chemical Technology and Development, 2024, 53(07): 73-78.), Zhang Yanping et al. combined iron-rich sludge with walnut shells, pyrolyzed at 900°C for 2h to prepare biochar and used it for the removal of methylene blue from printing and dyeing wastewater ([3] Zhang Yanping, Fan Xuteng, Peng Xiangshi, et al. Study on the adsorption performance of iron-rich sludge biochar on methylene blue [J]. Applied Chemical Industry, 2022, 51(9): 2553-2557.). Salix psammophila is a widely planted vegetation for desertification control. It is a shrub with dense branches and is not afraid of sand pressure. However, Salix psammophila must be pruned every 3 to 5 years to grow better. The biomass of Salix psammophila abandoned after pruning is rich in lignin, cellulose and hemicellulose, and has excellent properties for preparing biochar. The remaining Salix psammophila branches after pruning are made into biochar after high-temperature oxygen-limited pyrolysis, which can not only avoid the waste of biomass resources, but also adsorb pollutants and repair contaminated soil and wastewater. Wen Junfeng et al. used Salix psammophila activated at high temperature as a biosorbent to study the adsorption performance of phenolic substances in simulated wastewater. The results showed that the maximum adsorption capacity of phenol in simulated wastewater by Salix psammophila activated at high temperature can reach 243.90 mg·g -1([4] Wen Junfeng, Liu Xia, Gao Liguo, et al. Study on the adsorption performance of Salix psammophila biosorbent on phenol-containing wastewater [J]. New Chemical Materials, 2018, 46(8), 276-280.). Zhang Jing made biochar from the remaining Salix psammophila strips after pruning through high-temperature oxygen-limited pyrolysis, and used it for soil remediation of heavy metal pollution in mining areas. The results showed that Salix psammophila biochar had a good inhibitory effect on the migration of heavy metals in soils with different degrees of pollution ([5] Zhang Jing. Study on the improvement of copper pollution by Salix psammophila biochar [D]. Inner Mongolia Agricultural University, 2017.).

[0006] The above studies show that iron-rich sludge and Salix psammophila waste are good materials for preparing biochar and using them for contaminated soil remediation and adsorption of phenolic pollutants. However, currently, iron-rich sludge and Salix psammophila biochar are mainly used for heavy metal pollution remediation, and there are few studies on the adsorption of phenolic pollutants. In addition, there is no literature published on the preparation of phenolic soil contamination remediation materials using Salix psammophila biomass and iron-containing sludge. Summary of the invention

[0007] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a phenolic soil contamination remediation material and a preparation method and application thereof, and the iron-containing sludge discharged from the Fenton treatment unit of the waste paper papermaking industry wastewater is co-pyrolyzed with the waste Salix psammophila biomass to prepare a composite soil remediation material, so that it can play a role in strengthening the remediation of phenolic contaminated soil, while achieving the technical effect of low cost and waste treatment; the iron-containing sludge and the Salix psammophila biomass are co-pyrolyzed to form an environmentally safe composite material with magnetism and containing iron and oxygen multifunctional groups, which adsorbs phenolic pollutants through electrostatic attraction, π-π interaction, complexation and electron transfer, and Fe 2+ / Fe 3+ Redox-driven indigenous microorganisms accelerate electron transfer and enhance metabolic activity, thereby achieving the technical effect of enhancing the remediation of phenol-contaminated soil.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] A phenolic soil pollution remediation material, the raw materials of which include Salix psammophila branch debris and iron-containing sludge particles in a mass ratio of 1:4 to 2:1;

[0010] The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm;

[0011] The Salix psammophila branch debris is collected from desertified areas, air-dried and stored at room temperature after collection; before preparing biochar, it is dried overnight and ground into 1-2 mm debris.

[0012] After drying, the iron-containing sludge particles have an ash content of 68.8-76%, a carbon content of 6.8-8.4%, and a Fe content of 42.6-47.6%.

[0013] After drying, the ash content of the Salix psammophila debris is 12.5-17.5%, the carbon content is 75.5-82.5%, and the Fe content is 0-0.02%.

[0014] A method for preparing a phenolic soil pollution remediation material comprises the following steps:

[0015] S1. The dried Salix psammophila branch debris and the iron-containing sludge particles are uniformly mixed in a mass ratio of 1:4 to 2:1 to prepare a mixed raw material;

[0016] S2, placing the mixed raw materials obtained in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set at 35-45°C, and the temperature is set at 9-11°C min -1 The temperature is raised to 400-600° C., maintained for 1-1.5 hours, and naturally cooled to room temperature to obtain a phenolic soil pollution remediation material.

[0017] The yield of the prepared phenolic soil pollution remediation material is 50.22-78.38%, the ash content is 41.57-72.36%, the pH is 7.89-9.21, and the specific surface area is 80.90-90.05m 2 ·g -1 , pore size is 4.63~5.17nm, and it is magnetic.

[0018] The prepared phenolic soil pollution remediation material has H / C<0.4 and O / C<0.4, which meets the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC) and has good aromaticity and stability.

[0019] The prepared phenolic soil contamination remediation material has an Fe content of 54.82-60.18%, a Ca content of 7.14-8.31%, and an infrared spectrum Fe=O characteristic peak (580cm - 1) and the characteristic peaks of aromatic compounds (850cm - 1 Monosubstituted benzene ring = CH out-of-plane bending peak, 2900cm - 1-CH2- asymmetric stretching vibration peak and 3100cm - 1 is the stretching vibration peak of the benzene ring -CH=CH2).

[0020] The prepared phenolic soil contamination remediation material has the ability to quickly adsorb phenol, with an adsorption equilibrium time of 50 to 180 minutes and a maximum adsorption capacity of 7.82 to 8.71 mg·g -1 .

[0021] A phenolic soil pollution remediation material is used. The prepared phenolic soil pollution remediation material is added to phenol-contaminated soil to strengthen the bioremediation of phenol-contaminated soil. After completion, the residual phenol concentration and microbial community in the soil are tested to evaluate the pollution remediation effect.

[0022] A method for applying a phenolic soil pollution remediation material comprises the following steps:

[0023] Step 1: Add 4-6% (w / w) of a phenolic soil contamination remediation material to 100 mg kg -1 Phenol contaminated soil, stir evenly;

[0024] Step 2: Take samples at 1d, 2d, and 3d to test the residual phenol concentration in the soil and evaluate the phenol remediation effect; take samples at 1d, 2d, and 3d to analyze the changes in soil functional bacteria using 16S rDNA high-throughput sequencing technology.

[0025] The final remediation effect was 98.75% phenol removal within 2 days. The prepared phenolic soil pollution remediation material significantly stimulated the proliferation of Exiguobacterium and Variovorax bacteria with phenol degradation performance, among which Exiguobacterium is a magnetite-loving microorganism. On the 1st and 3rd days of remediation, the abundance of Exiguobacterium and Variovorax increased from the initial 0.64% to 18.46% and 18.05%, which was significantly higher than 0.34% and 0.03% without any addition.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention uses the iron-containing sludge discarded from the Fenton treatment unit of wastewater from a waste paper mill and the waste biomass of Salix psammophila, a common crop for desertification control, as raw materials, and prepares a low-cost environmental functional material with magnetism and phenol pollutant adsorption performance through co-pyrolysis, which can be used to accelerate the bioremediation of phenol-contaminated soil. The significant advantages and technical effects include: 1. Realizing the resource recycling of iron-containing sludge and waste biomass, and achieving the technical effect of using waste to treat pollution; 2. No secondary modification is required for the biochar material prepared by pyrolysis, and a functional material with a large specific surface area, magnetism and compliance with the application standards of the European Biochar Foundation (EBC) as a soil conditioner can be directly prepared by parameter setting, with the technical effect of low price and high quality; 3. Through the control of technical parameters, a composite functional material rich in iron oxide and organic functional groups is prepared, so that it has phenol adsorption performance and can achieve a large amount of phenol adsorption in a short time; 4. Adding an appropriate amount of the composite biochar material prepared by the present invention to phenol-contaminated soil can activate the large-scale reproduction of bacteria with phenol degradation performance, thereby significantly accelerating the repair rate of phenol-contaminated soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A phenolic soil contamination remediation material SFB500 was prepared in Example 1 to enhance the bioremediation effect of soil contamination.

[0029] Figure 2 The bacterial flora changes of enhanced soil pollution bioremediation prepared as a phenolic soil pollution remediation material SFB500 in Example 1. DETAILED DESCRIPTION

[0030] The present invention is described in detail below in conjunction with embodiments and drawings.

[0031] Example 1, a phenolic soil contamination remediation material SFB500, whose raw materials include Salix psammophila branch debris and iron-containing sludge particles in a mass ratio of 1:1;

[0032] The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm;

[0033] After drying, the ash content of iron-containing sludge particles was 72.4%, the carbon content was 7.6%, and the Fe content was 45.1%;

[0034] The Salix psammophila branch debris was collected from the desertification area of ​​Yulin, air-dried and stored at room temperature after collection; before preparing the biochar, it was dried overnight and ground into 1-2 mm debris;

[0035] After drying, the ash content of Salix psammophila debris is 15.0%, the carbon content is 80.5%, and the Fe content is 0.02%.

[0036] A method for preparing phenolic soil pollution remediation material SFB500 comprises the following steps:

[0037] S1. The dried Salix psammophila branch debris and the iron-containing sludge particles are uniformly mixed in a mass ratio of 1:1 to prepare a mixed raw material;

[0038] S2, placing the mixed raw materials obtained in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set to 40°C, the temperature is set to 10°C min -1 The temperature was raised to 500°C, maintained for 1 hour, and naturally cooled to room temperature to obtain a phenolic soil contamination remediation material SFB500.

[0039] The yield of SFB500, a phenolic soil contamination remediation material prepared, was 58.26%, the ash content was 69.90%, the pH was 8.81, and the specific surface area was 90.05 m 2 ·g -1 , pore size is 4.63nm, and it is magnetic.

[0040] The prepared phenolic soil pollution remediation material SFB500 has an H / C of 0.03 (<0.4) and an O / C of 0.26 (<0.4), which meets the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC) (i.e. H / C <0.4 and O / C <0.4) and has good aromaticity and stability.

[0041] The prepared phenolic soil contamination remediation material SFB500 has an Fe content of 59.67%, a Ca content of 7.70%, and an infrared spectrum Fe=O characteristic peak (580cm - 1) and the characteristic peaks of aromatic compounds (850cm - 1 Monosubstituted benzene ring = CH out-of-plane bending peak, 2900cm - 1-CH2- asymmetric stretching vibration peak and 3100cm - 1 is the stretching vibration peak of the benzene ring -CH=CH2).

[0042] The prepared phenolic soil contamination remediation material SFB500 has the ability to quickly adsorb phenol, with an adsorption equilibrium time of 50 min and a maximum adsorption capacity of 8.71 mg·g -1 .

[0043] The invention discloses an application of a phenolic soil pollution remediation material. The prepared phenolic soil pollution remediation material SFB500 is added to phenol-contaminated soil to strengthen the bioremediation of phenol-contaminated soil. After completion, the residual phenol concentration and microbial community in the soil are tested to evaluate the pollution remediation effect.

[0044] Example 2, a phenolic soil contamination remediation material SFB600, whose raw materials include Salix psammophila branch debris and iron-containing sludge particles in a mass ratio of 1:4;

[0045] The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm;

[0046] After drying, the ash content of iron-containing sludge particles was 72.4%, the carbon content was 7.6%, and the Fe content was 45.1%;

[0047] The Salix psammophila branch debris was collected from the desertification area of ​​Yulin, air-dried and stored at room temperature after collection; before preparing the biochar, it was dried overnight and ground into 1-2 mm debris;

[0048] After drying, the ash content of Salix psammophila debris is 15.0%, the carbon content is 80.5%, and the Fe content is 0.02%.

[0049] A method for preparing phenolic soil pollution remediation material SFB600 comprises the following steps:

[0050] S1. The dried Salix psammophila branch debris and the iron-containing sludge particles are uniformly mixed in a mass ratio of 1:4 to prepare a mixed raw material;

[0051] S2, placing the mixed raw materials obtained in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set to 45°C, the temperature is set to 11°C·min -1 The temperature was raised to 600°C, maintained for 1 hour, and naturally cooled to room temperature to obtain a phenolic soil contamination remediation material SFB600.

[0052] The yield of SFB600, a phenolic soil contamination remediation material prepared, was 78.38%, the ash content was 72.36%, the pH was 9.21, and the specific surface area was 80.90 m 2 ·g -1 , pore size is 5.17nm, and it is magnetic.

[0053] The prepared phenolic soil pollution remediation material SFB600 has an H / C of 0.09 (<0.4) and an O / C of 0.32 (<0.4), which meets the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC) (i.e. H / C <0.4 and O / C <0.4) and has good aromaticity and stability.

[0054] The prepared phenolic soil contamination remediation material SFB600 has an Fe content of 60.18%, a Ca content of 8.31%, and an infrared spectrum Fe=O characteristic peak (580cm- 1) and the characteristic peaks of aromatic compounds (850cm - 1 Monosubstituted benzene ring = CH out-of-plane bending peak, 2900cm - 1-CH2- asymmetric stretching vibration peak and 3100cm - 1 is the stretching vibration peak of the benzene ring -CH=CH2).

[0055] The prepared phenolic soil contamination remediation material SFB600 has the ability to quickly adsorb phenol, with an adsorption equilibrium time of 50 min and a maximum adsorption capacity of 7.82 mg g -1 .

[0056] A phenolic soil pollution remediation material is applied. A phenolic soil pollution remediation material SFB600 is added to phenol-contaminated soil to strengthen the bioremediation of phenol-contaminated soil. After completion, the residual phenol concentration and microbial community in the soil are tested to evaluate the pollution remediation effect.

[0057] Example 3, a phenolic soil contamination remediation material SFB400, whose raw materials include Salix psammophila branch debris and iron-containing sludge particles in a mass ratio of 2:1;

[0058] The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm;

[0059] After drying, the ash content of iron-containing sludge particles was 72.4%, the carbon content was 7.6%, and the Fe content was 45.1%;

[0060] The Salix psammophila branch debris was collected from the desertification area of ​​Yulin, air-dried and stored at room temperature after collection; before preparing the biochar, it was dried overnight and ground into 1-2 mm debris;

[0061] After drying, the ash content of Salix psammophila debris is 15.0%, the carbon content is 80.5%, and the Fe content is 0.02%.

[0062] A method for preparing phenolic soil pollution remediation material SFB400 comprises the following steps:

[0063] S1, the dried Salix psammophila branch debris and the iron-containing sludge particles are uniformly mixed in a mass ratio of 2:1 to prepare a mixed raw material;

[0064] S2, placing the mixed raw materials obtained in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set to 35°C, the temperature is set to 9°C·min -1The temperature was raised to 400°C, maintained for 1 hour, and naturally cooled to room temperature to obtain a phenolic soil contamination remediation material SFB400.

[0065] The yield of SFB400, a phenolic soil contamination remediation material prepared, was 50.22%, the ash content was 41.57%, the pH was 7.89, and the specific surface area was 85.57 m 2 ·g -1 , pore size is 4.81nm, and it is magnetic.

[0066] The prepared phenolic soil pollution remediation material SFB400 has an H / C of 0.02 (<0.4) and an O / C of 0.37 (<0.4), which meets the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC) (i.e. H / C <0.4 and O / C <0.4) and has good aromaticity and stability.

[0067] The prepared phenolic soil contamination remediation material SFB400 has an Fe content of 54.82%, a Ca content of 7.14%, and an infrared spectrum Fe=O characteristic peak (580cm - 1) and the characteristic peaks of aromatic compounds (850cm - 1 Monosubstituted benzene ring = CH out-of-plane bending peak, 2900cm - 1-CH2- asymmetric stretching vibration peak and 3100cm - 1 is the stretching vibration peak of the benzene ring -CH=CH2).

[0068] The prepared phenolic soil contamination remediation material SFB400 has the ability to quickly adsorb phenol, with an adsorption equilibrium time of 120 min and a maximum adsorption capacity of 7.93 mg·g -1 .

[0069] A phenolic soil pollution remediation material is applied. A phenolic soil pollution remediation material SFB400 is added to phenol-contaminated soil to strengthen the bioremediation of phenol-contaminated soil. After completion, the residual phenol concentration and microbial community in the soil are tested to evaluate the pollution remediation effect.

[0070] Example 4, a phenolic soil contamination remediation material SFB450, whose raw materials include Salix psammophila branch debris and iron-containing sludge particles in a mass ratio of 1.5:1;

[0071] The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm;

[0072] After drying, the iron-containing sludge particles have an ash content of 68.8%, a carbon content of 6.8%, and an Fe content of 42.6%;

[0073] The Salix psammophila branch debris was collected from the desertification area of ​​Yulin, air-dried and stored at room temperature after collection; before preparing the biochar, it was dried overnight and ground into 1-2 mm debris;

[0074] After drying, the ash content of Salix psammophila debris is 12.5%, the carbon content is 75.5%, and the Fe content is 0.00%.

[0075] A method for preparing phenolic soil pollution remediation material SFB300 comprises the following steps:

[0076] S1, the dried Salix psammophila branch debris and the iron-containing sludge particles are uniformly mixed in a mass ratio of 2:1 to prepare a mixed raw material;

[0077] S2, placing the mixed raw materials obtained in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set to 40°C, the temperature is set to 10°C min -1 The temperature was raised to 450°C, maintained for 1.5 hours, and naturally cooled to room temperature to obtain a phenolic soil contamination remediation material SFB450.

[0078] The yield of SFB450, a phenolic soil contamination remediation material prepared, was 53.71%, the ash content was 59.84%, the pH was 8.23, and the specific surface area was 86.41 m 2 ·g -1 , pore size is 4.77nm, and it is magnetic.

[0079] The prepared phenolic soil pollution remediation material SFB450 has an H / C of 0.03 (<0.4) and an O / C of 0.29 (<0.4), which meets the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC) (i.e. H / C <0.4 and O / C <0.4) and has good aromaticity and stability.

[0080] The prepared phenolic soil contamination remediation material SFB450 has an Fe content of 57.26%, a Ca content of 7.38%, and an infrared spectrum Fe=O characteristic peak (580cm - 1) and the characteristic peaks of aromatic compounds (850cm - 1 Monosubstituted benzene ring = CH out-of-plane bending peak, 2900cm - 1-CH2- asymmetric stretching vibration peak and 3100cm - 1 is the stretching vibration peak of the benzene ring -CH=CH2).

[0081] The prepared phenolic soil contamination remediation material SFB450 has the ability to quickly adsorb phenol, with an adsorption equilibrium time of 90 min and a maximum adsorption capacity of 8.05 mg·g -1 .

[0082] A phenolic soil pollution remediation material is used. The prepared phenolic soil pollution remediation material SFB450 is added to phenol-contaminated soil to strengthen the bioremediation of phenol-contaminated soil. After completion, the residual phenol concentration and microbial community in the soil are tested to evaluate the pollution remediation effect.

[0083] Example 5, a phenolic soil contamination remediation material SFB550, whose raw materials include Salix psammophila branch debris and iron-containing sludge particles in a mass ratio of 1:2;

[0084] The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm;

[0085] After drying, the iron-containing sludge particles have an ash content of 76.0%, a carbon content of 8.4%, and an Fe content of 47.6%;

[0086] The Salix psammophila branch debris was collected from the desertification area of ​​Yulin, air-dried and stored at room temperature after collection; before preparing the biochar, it was dried overnight and ground into 1-2 mm debris;

[0087] After drying, the ash content of Salix psammophila debris is 17.5%, the carbon content is 82.5%, and the Fe content is 0.02%.

[0088] A method for preparing a phenolic soil pollution remediation material SFB550 comprises the following steps:

[0089] S1, the dried Salix psammophila branch debris and the iron-containing sludge particles are uniformly mixed in a mass ratio of 2:1 to prepare a mixed raw material;

[0090] S2, placing the mixed raw materials obtained in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set to 40°C, the temperature is set to 10°C min -1 The temperature was raised to 550°C, maintained for 1.5 hours, and naturally cooled to room temperature to obtain a phenolic soil contamination remediation material SFB550.

[0091] The yield of SFB550, a phenolic soil contamination remediation material prepared, was 65.48%, the ash content was 70.52%, the pH was 9.04, and the specific surface area was 84.26 m 2 ·g -1 , pore size is 4.93nm, and it is magnetic.

[0092] The prepared phenolic soil pollution remediation material SFB200 has an H / C of 0.05 (<0.4) and an O / C of 0.35 (<0.4), which meets the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC) (i.e. H / C <0.4 and O / C <0.4) and has good aromaticity and stability.

[0093] The prepared phenolic soil contamination remediation material SFB550 has an Fe content of 60.04%, a Ca content of 8.27%, and an infrared spectrum Fe=O characteristic peak (580cm - 1) and the characteristic peaks of aromatic compounds (850cm - 1 Monosubstituted benzene ring = CH out-of-plane bending peak, 2900cm - 1-CH2- asymmetric stretching vibration peak and 3100cm - 1 is the stretching vibration peak of the benzene ring -CH=CH2).

[0094] The prepared phenolic soil contamination remediation material SFB550 has the ability to quickly adsorb phenol, with an adsorption equilibrium time of 45 min and a maximum adsorption capacity of 8.12 mg·g -1 .

[0095] A phenolic soil pollution remediation material is applied. A phenolic soil pollution remediation material SFB200 is added to phenol-contaminated soil to strengthen the bioremediation of phenol-contaminated soil. After completion, the residual phenol concentration and microbial community in the soil are tested to evaluate the pollution remediation effect.

[0096] Comparative Example 1, a phenolic soil contamination remediation material FB500, whose raw material is iron-containing sludge particles;

[0097] The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm;

[0098] After drying, the iron-containing sludge particles have an ash content of 72.4%, a carbon content of 7.6%, and an Fe content of 45.1%.

[0099] A preparation method of phenolic soil pollution remediation material FB500 comprises the following steps:

[0100] S1, taking the dried iron-containing sludge particles as raw materials;

[0101] S2, placing the raw materials in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set to 40°C, and the temperature is set to 10°C·min-1 The temperature was raised to 500°C, maintained for 1 hour, and naturally cooled to room temperature to obtain a pyrolysis biochar material FB500.

[0102] The yield of the prepared pyrolysis biochar material FB500 was 81.12%, the ash content was 96.35%, the pH was 8.11, and the specific surface area was 27.73 m 2 ·g -1 , pore size is 15.24nm, and it is magnetic.

[0103] The H / C (0.43) of the prepared pyrolysis biochar material FB500 was greater than 0.4, and the O / C (0.28) was less than 0.4, which did not meet the standards of the European Biochar Foundation (EBC) for biochar materials as soil conditioners (i.e., H / C < 0.4 and O / C < 0.4).

[0104] The prepared pyrolysis biochar material FB500 has an Fe content of 89.85%, a Ca content of 4.13%, and an infrared spectrum Fe=O characteristic peak (580cm - 1 near the metal-ligand vibration peak).

[0105] The adsorption equilibrium time of phenol by the prepared pyrolysis biochar material FB500 was 10 min, and the maximum adsorption capacity was only 2.53 mg·g -1 .

[0106] Comparative Example 2, a phenolic soil contamination remediation material SLB500, whose raw materials include Salix psammophila branch debris,

[0107] The Salix psammophila branch debris was collected from the desertification area of ​​Yulin, air-dried and stored at room temperature after collection; before preparing the biochar, it was dried overnight and ground into 1-2 mm debris;

[0108] After drying, the ash content of Salix psammophila debris is 15.0%, the carbon content is 80.5%, and the Fe content is 0.02%.

[0109] A method for preparing phenolic soil pollution remediation material SLB500 comprises the following steps:

[0110] S1, taking dried Salix psammophila debris as raw material;

[0111] S2, placing the raw materials in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set to 40°C, and the temperature is set to 10°C·min -1 The temperature was raised to 500°C, maintained for 1 hour, and naturally cooled to room temperature to obtain a pyrolysis biochar material SLB500.

[0112] The yield of the prepared pyrolysis biochar material SLB500 was 32.65%, the ash content was 9.14%, the pH was 7.89, and the specific surface area was 3.85 m 2 ·g -1 , pore size is 8.62nm, non-magnetic.

[0113] The H / C of SLB500, a phenolic soil pollution remediation material prepared, is 0.14 (<0.4) and O / C is 0.87 (>0.4), which does not meet the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC) (i.e., H / C <0.4 and O / C <0.4).

[0114] The prepared phenolic soil contamination remediation material SLB500 has an Fe content of 0.59% and a Ca content of 20.09%, and has a characteristic peak of aromatic compound structure (850cm - 1 Monosubstituted benzene ring = CH out-of-plane bending peak, 2900cm - 1-CH2- asymmetric stretching vibration peak and 3100cm - 1 is the stretching vibration peak of the benzene ring -CH=CH2).

[0115] The prepared phenolic soil contamination remediation material SLB500 has the ability to adsorb phenol, but the adsorption rate is slow, the adsorption equilibrium time is 250min, and the maximum adsorption capacity is 9.46mg·g -1 .

[0116] The basic characteristics of the materials prepared in Examples 1, 2, 3, 4, 5 and Comparative Examples 1 and 2 are shown in Table 1. In comparison, the materials prepared in the Examples have the structural characteristics of both raw materials, are magnetic, and can achieve large-scale adsorption of phenol relatively quickly.

[0117] Table 1

[0118]

[0119]

[0120] SSA: specific surface area; APS: average pore size; +: yes; -: no

[0121] The application of SFB500, a phenolic soil contamination remediation material prepared in Example 1, is described in detail below.

[0122] An application method of phenolic soil pollution remediation material SFB500 comprises the following steps:

[0123] Step 1: Add 5% (w / w) of the phenolic soil contamination remediation material SFB500 prepared in Example 1 to 100 mg kg-1 Phenol-contaminated soil was stirred evenly; at the same time, a control group (CK) with added bioinhibitors and a natural attenuation group (NA) without any additions were set up;

[0124] Step 2: Take samples at 1d, 2d, and 3d to test the residual phenol concentration in the soil and evaluate the phenol remediation effect; take samples at 1d, 2d, and 3d to analyze the changes in soil functional bacteria through 16S rDNA high-throughput sequencing technology to identify the functional bacteria that drive phenol degradation.

[0125] The final restoration effect is as follows Figure 1 As shown, the residual phenol rates of the control group (CK) with added bioinhibitors at 1d, 2d, and 3d were 95.67±5.88%, 83.94±2.46%, and 67.39±0.20%, respectively. The residual phenol rate of the natural attenuation group (NA) without any additions at the 2nd day was 78.62±6.96%, while the residual phenol rate of the experimental group with added materials prepared in Example 3 at the 2nd day was only 1.25±0.23%, achieving rapid enhanced phenol degradation.

[0126] Changes in soil functional bacteria Figure 2 As shown in the figure: Initial (initial soil sample); NA (no addition); SFB500 (composite material SFB500 of Example 3 is added). The bacterial community structure changes significantly during the degradation of phenol. SFB500, a phenolic soil pollution remediation material prepared in Example 3, significantly stimulated the proliferation of Exiguobacterium and Variovorax with phenol degradation performance (where Exiguob acterium is a magnetite-loving microorganism); in the initial soil sample, the abundance of Exiguobacterium and Variovorax accounted for 0.61% and 0.03%, respectively; in the natural attenuation group (NA) without any addition, the abundance of Exiguobacterium and Variovorax on the first day accounted for 0.32% and 0.02%, respectively, and the abundance of Exiguob acterium and Variovorax on the third day accounted for 0.03% and 0.00%, respectively. In the experimental group in which SFB500, a phenolic soil contamination remediation material prepared in Example 3, was added, the abundances of Exiguobacterium and Variovorax on the first day of degradation were 17.50% and 0.96%, respectively, and the abundances of Exiguobacterium and Variovorax on the third day of degradation were 8.06% and 12.03%, respectively.

[0127] The application effects of Embodiment 2, Embodiment 3, Embodiment 4 and Embodiment 5 of the present invention are similar to that of Embodiment 1.

Claims

1. A phenolic soil contamination remediation material, characterized in that: The raw materials include Salix psammophila branch debris and iron-containing sludge particles in a mass ratio of 1:4 to 2:1; The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm; The Salix psammophila branch debris is collected from desertified areas, air-dried and stored at room temperature after collection; before preparing biochar, it is dried overnight and ground into 1-2 mm debris.

2. The phenolic soil contamination remediation material according to claim 1, characterized in that: After drying, the iron-containing sludge particles have an ash content of 68.8-76%, a carbon content of 6.8-8.4%, and a Fe content of 42.6-47.6%.

3. The phenolic soil contamination remediation material according to claim 1, characterized in that: After drying, the ash content of the Salix psammophila debris is 12.5-17.5%, the carbon content is 75.5-82.5%, and the Fe content is 0-0.02%.

4. The method for preparing a phenolic soil contamination remediation material according to claim 1, characterized in that: The following steps are involved: S1. The dried Salix psammophila branch debris and the iron-containing sludge particles are uniformly mixed in a mass ratio of 1:4 to 2:1 to prepare a mixed raw material; S2, placing the mixed raw materials obtained in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set at 35-45°C, the temperature is set at 9-11°C·min -1 The temperature is raised to 400-600° C., maintained for 1-1.5 hours, and naturally cooled to room temperature to obtain a phenolic soil pollution remediation material.

5. The preparation method according to claim 4, characterized in that: The yield of the prepared phenolic soil pollution remediation material is 50.22-78.38%, the ash content is 41.57-72.36%, the pH is 7.89-9.21, and the specific surface area is 80.90-90.05m 2 ·g -1 , pore size is 4.63~5.17nm, magnetic; The prepared phenolic soil pollution remediation material has H / C<0.4 and O / C<0.4, which meets the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC) and has good aromaticity and stability. The prepared phenolic soil contamination remediation material has an Fe content of 54.82-60.18%, a Ca content of 7.14-8.31%, and an infrared spectrum Fe=O characteristic peak (580cm -1 Nearby metal-ligand vibration peaks) and characteristic peaks of aromatic compounds (850cm -1 Nearby monosubstituted benzene ring =CH out-of-plane bending peak, 2900cm -1 Nearby -CH2- asymmetric stretching vibration peak and 3100cm -1 Nearby benzene ring -CH=CH2 stretching vibration peak); The prepared phenolic soil contamination remediation material has the ability to quickly adsorb phenol, with an adsorption equilibrium time of 50 to 180 minutes and a maximum adsorption capacity of 7.82 to 8.71 mg·g -1 .

6. The use of a phenolic soil contamination remediation material prepared according to claim 4, characterized in that: The prepared phenolic soil pollution remediation material is added to phenol-contaminated soil to enhance the bioremediation of phenol-contaminated soil. After completion, the residual phenol concentration and microbial community in the soil are tested to evaluate the pollution remediation effect.

7. The method for applying the phenolic soil contamination remediation material as claimed in claim 6, characterized in that: The following steps are involved: Step 1: Add 4-6% (w / w) of a phenolic soil contamination remediation material to 100 mg kg -1 Phenol contaminated soil, stir evenly; Step 2: Take samples at 1d, 2d, and 3d to test the residual phenol concentration in the soil and evaluate the phenol remediation effect; take samples at 1d, 2d, and 3d to analyze the changes in soil functional bacteria using 16S rDNA high-throughput sequencing technology.

8. The application method according to claim 7, characterized in that: The final remediation effect was 98.75% phenol removal within 2 days. The prepared phenolic soil pollution remediation material significantly stimulated the proliferation of Exiguobacterium and Variovorax bacteria with phenol degradation performance, among which Exiguobacterium is a magnetite-loving microorganism. On the 1st and 3rd days of remediation, the abundance of Exiguobacterium and Variovorax increased from the initial 0.64% to 18.46% and 18.05%.

9. A phenolic soil contamination remediation material SFB500, characterized by: Its raw materials include Salix psammophila branch debris and iron-containing sludge particles in a mass ratio of 1:1; The iron-containing sludge is taken from the wastewater Fenton treatment unit of the paper mill and is sealed and stored at low temperature after collection; before preparing biochar, the iron-containing sludge is centrifuged and dehydrated after natural sedimentation, dried overnight, and after fully removing the water, it is ground into particles of 1-2 mm; After drying, the ash content of iron-containing sludge particles was 72.4%, the carbon content was 7.6%, and the Fe content was 45.1%; The Salix psammophila branch debris was collected from the desertification area of ​​Yulin, air-dried and stored at room temperature after collection; before preparing the biochar, it was dried overnight and ground into 1-2 mm debris; After drying, the ash content of Salix psammophila debris is 15.0%, the carbon content is 80.5%, and the Fe content is 0.02%.

10. The method for preparing the phenolic soil contamination remediation material SFB500 according to claim 9, characterized in that: The following steps are involved: S1. The dried Salix psammophila branch debris and the iron-containing sludge particles are uniformly mixed in a mass ratio of 1:1 to prepare a mixed raw material; S2, placing the mixed raw materials obtained in step S1 in a tube furnace for anaerobic pyrolysis, the conditions are: the initial temperature is set to 40°C, the temperature is set to 10°C min -1 The temperature was raised to 500°C, maintained for 1 hour, and naturally cooled to room temperature to obtain a phenolic soil contamination remediation material SFB500; The yield of SFB500, a phenolic soil contamination remediation material prepared, was 58.26%, the ash content was 69.90%, the pH was 8.81, and the specific surface area was 90.05 m 2 ·g -1 , pore size is 4.63nm, magnetic; The H / C of SFB500, a phenolic soil pollution remediation material prepared, is 0.03 and O / C is 0.26, which meets the standards of biochar materials as soil conditioners proposed by the European Biochar Foundation (EBC), that is, H / C < 0.4 and O / C < 0.4, and has good aromaticity and stability. The prepared phenolic soil contamination remediation material SFB500 has an Fe content of 59.67%, a Ca content of 7.70%, and an infrared spectrum Fe=O characteristic peak (580cm -1 Nearby metal-ligand vibration peaks) and characteristic peaks of aromatic compounds (850cm -1 Nearby monosubstituted benzene ring =CH out-of-plane bending peak, 2900cm -1 Nearby -CH2- asymmetric stretching vibration peak and 3100cm -1 Nearby benzene ring -CH=CH2 stretching vibration peak); The prepared phenolic soil contamination remediation material SFB500 has the ability to quickly adsorb phenol, with an adsorption equilibrium time of 50 min and a maximum adsorption capacity of 8.71 mg·g -1 .

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