Preparation of surface electron polarization distribution biomass charcoal and application of surface electron polarization distribution biomass charcoal in water treatment

Abstract

The invention relates to the field of sewage treatment, and discloses a surface electron polarization distribution biomass charcoal preparation method, which comprises: collecting pigeon droppings, drying to make the water content lower than 10%, and marking as a precursor A; roasting the solid A at 250-600 DEG C to obtain a solid B; weighing the solid B, diatomite and dopamine according to a fixed ratio of 1: (0-1): (0-1), fully and uniformly mixing, and carrying out ball milling to obtain a solid C; the preparation method comprises the following steps: weighing metal aluminum salt, cobalt salt, copper salt and other single or combined reagents in a fixed proportion, and dissolving in water to form an impregnation liquid A; adjusting the pH value of the impregnation liquid A to be neutral to alkaline, then adding the solid C, fully impregnating, and aging in a drying oven at 50-120 DEG C for 1-2 hours to obtain a solid D; and roasting and carbonizing the solid D in an inert atmosphere, and naturally cooling to obtain the target catalyst EPOA-1. Furthermore, the EPOA-1 is applied to removal of refractory pollutants in actual water so as to further reduce COD (Chemical Oxygen Demand) of effluent, improve the quality of the effluent and ensure safe and up-to-standard discharge of the effluent.

Description

Technical Field

[0001] The present invention relates to the field of sewage treatment, and in particular to the preparation of biochar with surface electron polarization distribution and its application in water treatment. Background Art

[0002] Industrial wastewater, municipal sewage and mixed sewage have complex compositions, often containing difficult-to-degrade organic matter with complex structures and poor biodegradability. Traditional biochemical treatment alone is no longer able to meet increasingly stringent emission standards. In order to achieve deep removal of COD in wastewater, it is usually necessary to add advanced oxidation processes. However, conventional advanced oxidation technologies face many challenges, including high construction costs, high operating costs, difficulty in handling hazardous waste by-products, intolerance to salt, and high environmental safety risks. This not only leads to a sharp increase in resource and energy consumption in the water treatment process, but also leads to large amounts of carbon emissions, which have a negative impact on the environment.

[0003] Biochar, with its highly developed pore structure and large specific surface area, is widely used in environmental protection, chemical engineering, medicine, food, and other fields. It is particularly effective against recalcitrant organic pollutants in wastewater, making it a popular material in water treatment. my country is one of the world's largest producers of meat pigeons, with a large breeding industry. However, with the booming pigeon farming industry, the treatment and disposal of pigeon manure has become a matter of increasing environmental concern. Traditionally, pigeon manure is treated through composting and fermentation, but this process results in nitrogen and phosphorus losses and the generation of ammonia, volatile sulfur compounds, and other volatile organic pollutants, resulting in high environmental loads. Furthermore, manure disposal often breeds pathogenic microorganisms, and residual antibiotics can enter the environment, generating drug-resistant genes and posing a potential threat to ecosystems and human health. Therefore, the development of new, environmentally friendly and sustainable treatment technologies is crucial. Research has shown that pigeon manure is rich in organic and inorganic substances such as carbon, nitrogen, phosphorus, potassium, and iron, making it an ideal resource for the production of activated carbon.

[0004] In view of this, this patent transforms pigeon manure into a resource to prepare a new type of biomass carbon water treatment material with surface electronic polarization distribution, and based on this, develops an electronic polarization driving oxygen activation technology (Electronic Polarization driving Oxygen Activation Technology, referred to as EPOA technology) for deep purification of sewage and wastewater, reducing the water treatment process's dependence on large-scale oxidants and electricity consumption, reducing carbon footprint, and ensuring that water quality meets discharge standards. Summary of the Invention

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: development of EPOA technology and its application in water treatment, comprising the following steps:

[0006] 1. Collect pigeon droppings and dry them at a constant temperature of 50-100℃ until the moisture content is less than 10%. This is recorded as precursor A.

[0007] 2. Calcinate solid A at 250-600 °C for 1-3 h at a heating rate of 5-10 °C / min, and obtain solid B after natural cooling.

[0008] 3. Weigh solid B, diatomaceous earth, and dopamine in a fixed ratio of 1:(0-1):(0-1), mix thoroughly, and ball-mill to obtain solid C.

[0009] 4. Weigh a fixed proportion of metal aluminum salt, cobalt salt, copper salt, etc., alone or in combination, and dissolve them in water to form an impregnation solution A.

[0010] 5. Use an alkaline reagent to adjust the pH of the impregnation solution A to neutral to alkaline, add solid C, fully impregnate, and place in an oven at 50-120℃ for 1-2 hours to obtain solid D.

[0011] 6. Calcinate and carbonize the solid D in a non-oxidizing inert atmosphere, including but not limited to nitrogen or argon. After cooling naturally, the target catalyst EPOA-1 is obtained.

[0012] 7. Apply EPOA-1 to the removal of refractory pollutants in actual water, in order to further reduce effluent COD, improve effluent water quality, and ensure effluent safety and compliance with discharge standards.

[0013] Preferably, the drying temperature in step 1 is 60°C.

[0014] Preferably, the calcination temperature in step 2 is preferably 300° C., with a heating rate of 5° C. / min; and the calcination time is preferably 2 h.

[0015] Preferably, in step 3, the mass ratio of the solid B, diatomaceous earth and dopamine is 1:0.2:0.1.

[0016] Preferably, the metal salts contained in the impregnation solution A in step 4 are selected from sulfate (aluminum / cobalt / copper), chloride (aluminum / cobalt / copper) or nitrate (aluminum / cobalt / copper); further, chloride (aluminum / cobalt / copper) is preferred.

[0017] Preferably, the mass ratio of the addition amount of aluminum, cobalt, copper salt and solid B is: (0-1): (0-1): (0-1): 1.

[0018] Preferably, the alkaline reagent in step 5 includes but is not limited to Na2HPO4•12H2O, K2HPO4, ammonia water, NaOH, KOH, etc., alone or in combination; further, the pH of the impregnation solution A is preferably adjusted to the range of 8.5-9.

[0019] Preferably, the drying temperature in step 5 is preferably 80° C.; and the aging time is preferably 2 h.

[0020] Preferably, the carbonization process in step 6 is carried out under a nitrogen atmosphere, with the temperature at 400-900° C. maintained for 1-3 hours; further, the heating rate is preferably 5-10° C. / min, and the calcination is carried out for 2 hours.

[0021] The present invention also provides an EPOA-1 water treatment catalyst, which is prepared according to the above preparation method.

[0022] The present invention also provides the use of the above-mentioned EPOA-1 water treatment catalyst in the deep treatment of municipal sewage. Beneficial effects

[0023] Compared with the prior art, the present invention provides a preparation method of biochar with surface electron polarization distribution and its application in water treatment, which has the following beneficial effects:

[0024] 1. The raw materials for the preparation of the EPOA series water treatment catalysts are cheap and easily available, and they solve the environmental pollution problem that may be caused by improper treatment and disposal of pigeon manure, achieving the goal of "treating waste with waste".

[0025] 2. The EPOA technology can effectively remove difficult-to-degrade organic pollutants in water and reduce the COD of wastewater under normal temperature and pressure conditions without the need for any external energy assistance or consumption of chemical oxidants.

[0026] 3. EPOA-1 has many active sites and a large specific surface area. Its active components are largely exposed on the catalyst surface, making it easily accessible to DO and pollutants in water and not significantly affected by steric hindrance and capillary phenomena.

[0027] 4. EPOA technology does not produce solid foreign matter such as iron sludge during the reaction process, and does not require foreign matter removal equipment.

[0028] 5. EPOA technology has good stability in removing COD from wastewater, making it easy to separate from water and recycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 Scanning electron microscopy (SEM) image of EPOA-1-C.

[0031] Figure 2. Removal performance of EPOA-1-C for new pollutants such as difficult-to-degrade antibiotics in water.

[0032] Fig. 3 Effects of complex salinity anions on the removal of new pollutants by EPOA-1-C.

[0033] Figure 4. EPOA-1-C performance in deep treatment of rural river sewage. Specific implementation plan

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0035] Please refer to Figures 1-4 for an electron polarization distribution driven oxygen activation technology and its application in water treatment, and refer to Examples 1 to 3 below.

[0036] Example 1

[0037] An embodiment of the EPOA technology of the present invention, a method for preparing the EPOA-1-A catalyst in this embodiment, comprises the following steps:

[0038] 1. Collect pigeon droppings and dry them at 80℃ until the moisture content is less than 10%. This is recorded as Precursor A.

[0039] 2. Calcinate solid A at 250°C at a heating rate of 10°C / min, and obtain solid B after natural cooling.

[0040] 3. Weigh solid B, diatomaceous earth, and dopamine in a fixed ratio of 1:0.3:0.2, mix thoroughly, and ball-mill to obtain solid C.

[0041] 4. Weigh aluminum chloride and cobalt chloride in a mass ratio of 0.5:0.2:1 to solid B; dissolve the two metal salts in water to form impregnation solution A.

[0042] 5. Use 2mM NaOH solution to adjust the pH of impregnation solution A to 8.5, add solid C, fully impregnate, and place The mixture was aged in an oven at 80°C for 2 h to obtain solid D.

[0043] 6. Calcinate solid D in a nitrogen atmosphere at 700°C for 2 h at a heating rate of 5°C / min. After cooling naturally, the target catalyst EPOA-1-A was obtained.

[0044] 7. Apply EPOA-1-A to the removal of refractory pollutants in actual water, in order to further reduce effluent COD, improve effluent water quality, and ensure effluent safety and compliance with discharge standards.

[0045] Example 2

[0046] An embodiment of the EPOA technology of the present invention, a method for preparing the EPOA-1-B catalyst in this embodiment, includes the following steps.

[0047] 1. Collect pigeon droppings and dry them at 80℃ until the moisture content is less than 10%. This is recorded as Precursor A.

[0048] 2. Calcinate solid A at 300°C with a heating rate of 10°C / min, and obtain solid B after natural cooling.

[0049] 3. Weigh solid B, diatomaceous earth, and dopamine in a fixed ratio of 1:0.1:0.1, mix thoroughly, and ball-mill to obtain solid C.

[0050] 4. Weigh aluminum chloride and copper chloride in a mass ratio of 0.3:0.2:1 to solid B; dissolve the two metal salts in water to form impregnation solution A.

[0051] 5. Use ammonia solution to adjust the pH of the impregnation solution A to 8.5, add solid C, fully impregnate, and place in an oven at 100°C for aging for 2 hours to obtain solid D.

[0052] 6. Calcinate solid D in a nitrogen atmosphere at 600°C for 2 h at a heating rate of 5°C / min. After cooling naturally, the target catalyst EPOA-1-B was obtained.

[0053] 7. Apply EPOA-1-B to the removal of refractory pollutants in actual water, in order to further reduce effluent COD, improve effluent water quality, and ensure effluent safety and compliance with discharge standards.

[0054] Example 3

[0055] An embodiment of the EPOA technology of the present invention, a method for preparing the EPOA-1-C catalyst in this embodiment, includes the following steps.

[0056] 1. Collect pigeon droppings and dry them at 80℃ until the moisture content is less than 10%. This is recorded as Precursor A.

[0057] 2. Calcinate solid A at 300°C with a heating rate of 10°C / min, and obtain solid B after natural cooling.

[0058] 3. Weigh solid B, diatomaceous earth, and dopamine in a fixed ratio of 1:0.1:0.1, mix thoroughly, and ball-mill to obtain solid C.

[0059] 4. Weigh copper chloride and solid B in a mass ratio of 0.1:1; dissolve copper chloride in water to form impregnation solution A.

[0060] 5. Use ammonia solution to adjust the pH of the impregnation solution A to 8.5, add solid C, fully impregnate, and place in an oven at 60°C for aging for 2 hours to obtain solid D.

[0061] 6. Calcinate solid D in a nitrogen atmosphere at 600°C for 2 h at a heating rate of 5°C / min. After cooling naturally, the target catalyst EPOA-1-C was obtained.

[0062] 7. Apply EPOA-1-C to the removal of refractory pollutants in actual water, in order to further reduce effluent COD, improve effluent water quality, and ensure effluent safety and compliance with discharge standards. Specific application examples

[0063] Any one of the EPOA catalysts (this patent takes EPOA-1-C prepared in Example 3 as an example) is selected and applied to the deep treatment of actual municipal sewage biochemical effluent.

[0064] Figure 1 (left) shows an SEM image of EPOA-1-C prepared in the examples. At a microscopic scale of 200 nm, it can be seen that the surface pore structure of the pigeon manure biochar EPOA-1-C was successfully manipulated through in-situ doping and surface complexation, resulting in a well-developed porous structure. Furthermore, EPOA-1-C is primarily composed of regularly shaped, blocky particles with numerous nanoscale particles formed on its surface. This is due to the metal-organic complex formed by the introduction of active metal components onto the catalyst surface, which facilitates the formation of multiple active sites on the EPOA-1-C surface.

[0065] Application Example 1

[0066] my country is the world's largest producer and consumer of antibiotics, and large quantities of incompletely degraded antibiotics are released into the environment annually. Data from 2013 show that China consumed approximately 162,000 tons of antibiotics, of which approximately 52% was used for veterinary medicine. The vast majority of these antibiotics are not absorbed by organisms and are instead released into the environment unchanged, posing a potential threat to aquatic ecosystems and human health. This study evaluated the effectiveness of EPOA-1-C in treating emerging antibiotic contaminants in water under ambient temperature and pressure by preparing aqueous solutions containing 10 mg / L of the new contaminants tetracycline hydrochloride (TC), sulfadiazine (SDZ), and ciprofloxacin (CIP). The reaction system was set up as follows: 0.5 g of EPOA-1-C was weighed and added to 50 mL of the contaminant solution. The solution was then placed in a 35°C constant temperature water bath for testing. Water samples were collected after 5, 15, 30, and 60 minutes of reaction time to determine the contaminant concentrations. As shown in Figure 2, in the EPOA-1-C reaction system, SDZ can be rapidly degraded within 15 minutes, TC removal rate within 60 minutes is as high as 98%, and ciprofloxacin removal rate is also above 80%. This system does not require external energy assistance or oxidant consumption, and completely utilizes the electrons and energy of endogenous pollutants in water to drive the activation of dissolved oxygen, generating oxidative hydroxyl radicals ( • OH), superoxide radicals (O2 •- ) and other species to oxidize and degrade pollutants.

[0067] Furthermore, to evaluate the adaptability of EPOA-1-C in complex saline media, the present invention systematically evaluated the effects of different salt ions on the TC removal performance of the EPOA-1-C system. Salt is one of the most significant environmental factors affecting the efficiency of conventional water treatment processes, and is difficult to overcome even with the consumption of large amounts of oxidants or energy. Encouragingly, in the present invention's system, the addition of salt ions at concentrations as high as 100 mM not only had no effect on TC removal, but actually accelerated water purification ( Figure 3). The system shows excellent adaptability to a variety of complex salt media. This is due to the regulation of the distribution of electronic polarization on the catalyst surface proposed by the present invention, which induces the preferential adsorption of pollutant molecules and dissolved oxygen molecules in water. The salt anions, due to their affinity for water molecules, will confine water molecules locally on the catalyst surface through intermolecular forces, causing the hydrogen bond network of water molecules to distort, which is conducive to more effective contact between pollutants and dissolved oxygen molecules and active sites. It also drives oxygen activation through surface electron transfer, generating oxidative free radicals to accelerate pollutant removal, thereby achieving high-efficiency and low-energy water purification under natural mild conditions.

[0068] Application Example 2

[0069] To evaluate the effectiveness of EPOA-1-C catalyst in actual wastewater purification, the present invention conducted experiments on wastewater from a rural river. The reaction system was set up as follows: 0.5g of EPOA-1-C was weighed and added to 50mL of wastewater. The reaction was carried out in a 35°C constant temperature water bath. Water samples were taken after 5, 15, 30, and 60 minutes of reaction to measure changes in ammonia nitrogen and COD in the wastewater. Figure 4 As shown, the wastewater COD was approximately 46 mg / L and ammonia nitrogen was approximately 22.5 mg / L. High ammonia nitrogen and organic matter content are the direct causes of river eutrophication. However, after treatment with the EPOA-1-C system, COD and ammonia nitrogen gradually decreased with increasing reaction time. Within 60 minutes, COD was reduced to 32 mg / L and ammonia nitrogen to 12.8 mg / L, significantly reducing the level of river water pollution. This successful application of the new EPOA technology in actual eutrophic river wastewater has important guiding significance for the development of new low-carbon, low-energy water treatment processes.

[0070] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing biochar with surface electron polarization distribution, characterized in that: The following steps are involved: Step 1: Collect pigeon droppings and dry them at a constant temperature of 50-100°C to make the moisture content less than 10%, which is recorded as precursor A; Step 2: calcining solid A at 250-600 °C for 1-3 h at a heating rate of 5-10 °C / min, and then cooling naturally to obtain solid B; Step 3: Solid B, diatomaceous earth, and dopamine were weighed in a fixed ratio of 1:(0-1):(0-1), mixed thoroughly, and ball-milled to obtain solid C; Step 4: Weigh a fixed ratio of metal aluminum salt, cobalt salt, copper salt, etc., alone or in combination, and dissolve them in water to form an impregnation solution A; Step 5: Use an alkaline reagent to adjust the pH of the impregnation solution A to neutral to alkaline, add solid C, fully impregnate, and place in an oven at 50-120°C for 1-2 hours to obtain solid D; Step 6: Calcine and carbonize the solid D in a non-oxidizing inert atmosphere, including but not limited to nitrogen or argon. After natural cooling, the target catalyst EPOA-1 is obtained. Step 7: Apply EPOA-1 to the removal of refractory pollutants in actual water, in order to further reduce the effluent COD, improve the effluent water quality, and ensure the safety of the effluent and meet the discharge standards.

2. The method for preparing biochar with surface electron polarization distribution according to claim 1, characterized in that: The drying temperature in step 1 is preferably 60°C.

3. The method for preparing biochar with surface electron polarization distribution according to claim 1, characterized in that: In step 2, the calcination temperature is preferably 300° C., the heating rate is 5° C. / min, and the calcination time is preferably 2 h.

4. The method for preparing biochar with surface electron polarization distribution according to claim 1, characterized in that: In step 3, the mass ratio of the solid B, diatomaceous earth and dopamine is 1:0.2:0.

1.

5. The method for preparing biochar with surface electron polarization distribution according to claim 1, characterized in that: In step 4, the metal salts contained in the impregnation solution A are selected from one of sulfate (aluminum / cobalt / copper), chloride (aluminum / cobalt / copper) or nitrate (aluminum / cobalt / copper); further, chloride (aluminum / cobalt / copper) is preferred; further, preferably, the mass ratio of the added amount of aluminum, cobalt, and copper salts to the solid B is: (0-1): (0-1): (0-1):

1.

6. The method for preparing biochar with surface electron polarization distribution according to claim 1, characterized in that: The alkaline reagent in step 5 includes but is not limited to Na2HPO4·12H2O, K2HPO4, ammonia, NaOH, KOH, etc. or a combination thereof; further, the pH of the impregnation solution A is adjusted preferably to the range of 8.5-9.

7. The method for preparing biochar with surface electron polarization distribution according to claim 1, characterized in that: In step 5, the drying temperature is preferably 80° C.; and the aging time is preferably 2 hours.

8. The method for preparing biochar with surface electron polarization distribution according to claim 1, characterized in that: The carbonization process in step 6 is carried out by calcining in a nitrogen atmosphere at a temperature of 400-900° C. for 1-3 hours; further, the heating rate is preferably 5-10° C. / min, and the calcination is carried out for 2 hours.

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