A method for degrading organic pollutants by using dissolved black carbon to activate oxidants
Patent Information
- Application Number
- CN202610922579.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-06-25
- Publication Date
- 2026-10-30
AI Technical Summary
然而，现有技术仍存在明显局限性：传统的渗透性反应屏障技术往往受限于固定反应区的位置，难以有效应对污染羽范围的扩大；而化学氧化技术虽然反应迅速，但常因氧化剂传输效率低、与污染物接触不充分等原因导致修复效果不佳
[0017]本发明中溶解态黑碳作为一种天然来源、易于迁移、表面富含活性位点的材料，其稳定的芳香结构确保了在复杂地下水环境中的持久活性，而丰富的表面官能团为高碘酸盐活化提供了多样化的反应位点，有效活化高碘酸盐，产生强氧化性物种，从而高效降解有机污染物。本发明利用绿色、易获取的溶解态黑碳进行活化，避免了外部能量输入或金属催化剂带来的成本与二次污染问题，为地下水有机污染治理提供了一种创新解决方案。
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Figure CN122999656A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of water pollution treatment technology, specifically relating to a method for degrading organic pollutants using dissolved black carbon to activate oxidants. Background Technology
[0002] Groundwater, as a vital source of drinking water and strategic water resources, is facing an increasingly serious threat of organic pollution globally. Currently, groundwater remediation primarily relies on in-situ remediation technologies, which involve removing, transforming, or fixing pollutants directly within the aquifer without extracting the groundwater. Compared to ex-situ remediation, in-situ remediation offers advantages such as less disturbance, higher remediation efficiency, and relatively lower cost. However, existing technologies still have significant limitations: traditional permeable reaction barrier technologies are often limited by the location of the fixed reaction zone, making it difficult to effectively address the expansion of the pollution plume; while chemical oxidation technologies, although reacting rapidly, often suffer from poor remediation results due to low oxidant transport efficiency and insufficient contact with pollutants. The treatment effectiveness of existing technologies is even more limited for aquifers with poor permeability or for non-aqueous liquid pollutants.
[0003] Periodate, as a strong oxidant, has shown significant potential in the field of organic pollution remediation in recent years. Compared with traditional oxidants such as persulfate and hydrogen peroxide, periodate exhibits higher oxidation selectivity, enabling it to specifically degrade organic pollutants containing unsaturated bonds and specific functional groups. However, periodate also faces several challenges in practical applications. Its oxidation rate is relatively slow, especially under conditions of low temperature, neutral pH, or low pollutant concentration, where its degradation efficiency for organic matter decreases significantly. Therefore, activation methods are needed to enhance the oxidation capacity of periodate. Common periodate activation methods include thermal activation, ultraviolet light activation, and transition metal ion activation, but each method has its limitations: thermal activation and ultraviolet light activation require external energy input, increasing operational complexity and cost; transition metal ion activation may lead to catalyst loss, precipitation clogging of aquifers, and other problems, affecting the durability of remediation effects. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides a method for in-situ remediation of organically polluted soil and groundwater using dissolved black carbon, offering a simple, low-cost, and environmentally friendly new approach for the remediation of organic pollution in groundwater.
[0005] The technical solution provided by this invention is as follows:
[0006] This invention provides a method for degrading organic pollutants using dissolved black carbon-activated oxidants, characterized by comprising the following steps: Obtain crop straw, pre-treat the crop straw to obtain biochar; The biochar was ground, sieved, and then added to deionized water. The mixture was then stirred and sonicated to obtain a suspension. The suspension is filtered, the filtrate is collected, and the pH of the filtrate is adjusted to a preset value to obtain a dissolved black carbon solution. The dissolved black carbon solution and oxidant are thoroughly mixed with the water to be treated to achieve the degradation of organic pollutants; wherein the oxidant is periodate.
[0007] Furthermore, the periodate is selected from one or more of sodium periodate, potassium periodate, and ammonium periodate.
[0008] Furthermore, the pretreatment of the crop straw includes: After being crushed, crop straw is passed through a 40-mesh sieve and placed in a muffle furnace for pyrolysis and carbonization under inert gas protection to obtain biochar.
[0009] Furthermore, the pyrolysis and carbonization conditions are as follows: heating from 20°C to 350-500°C at a rate of 5-10°C / min for 3-8 hours.
[0010] Furthermore, the biochar is ground, sieved, and then added to deionized water. The mass-to-volume ratio of the biochar powder obtained after grinding and sieving to the deionized water is 30-50g:480-800mL.
[0011] Furthermore, the sieving is done through a 100-mesh sieve; the ultrasonic treatment power is 100~200 W, and the time is 30~60 min; the filtration uses a 0.45 μm filter membrane.
[0012] Furthermore, the pH of the filtrate is adjusted to a preset value of 6.9 ± 0.1.
[0013] Furthermore, in the process of thoroughly mixing the dissolved black carbon solution and the oxidant with the water to be treated, the concentration of the dissolved black carbon solution is 20~40 mgC / L.
[0014] Furthermore, the crop straw is selected from at least one of corn straw, peanut straw, sorghum straw, and wheat straw.
[0015] Furthermore, the organic pollutants include, but are not limited to, diethyl phthalate.
[0016] Beneficial effects
[0017] In this invention, dissolved black carbon, a naturally sourced, easily migratable material with abundant surface active sites, possesses a stable aromatic structure that ensures sustained activity in complex groundwater environments. Its rich surface functional groups provide diverse reaction sites for periodate activation, effectively activating periodate to generate strong oxidizing species, thereby efficiently degrading organic pollutants. This invention utilizes green and readily available dissolved black carbon for activation, avoiding the costs and secondary pollution problems associated with external energy input or metal catalysts, thus providing an innovative solution for the remediation of organic pollution in groundwater.
[0018] Compared with traditional techniques for activating periodate (thermal activation, ultraviolet light activation, transition metal ion activation), this invention is rapid, simple, low-cost, and environmentally friendly. This invention develops an in-situ groundwater remediation technology based on dissolved black carbon activation of periodate, providing a simple, low-cost, and environmentally friendly new method for the remediation of organic pollution in groundwater. Attached Figure Description
[0019] Figure 1 A schematic diagram is shown below illustrating a method for degrading organic pollutants using dissolved black carbon as an oxidant according to the present invention.
[0020] Figure 2 This is a characterization diagram of the dissolved black carbon structure used in this invention;
[0021] Figure 3 These are the kinetic curves of the degradation of diethyl phthalate by dissolved black carbon activated periodate in Examples 1 to 3 of the present invention;
[0022] Figure 4 This is the free radical detection result of dissolved black carbon activated periodate according to the present invention. Detailed Implementation
[0023] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and should not be used to limit the scope of protection of the present invention.
[0024] This invention provides a method for degrading organic pollutants using dissolved black carbon-activated oxidants, comprising the following steps: Obtain crop straw, pre-treat the crop straw to obtain biochar; The biochar was ground, sieved, and then added to deionized water. The mixture was then stirred and sonicated to obtain a suspension. The suspension is filtered, the filtrate is collected, and the pH of the filtrate is adjusted to a preset value to obtain a dissolved black carbon solution. The dissolved black carbon solution and oxidant are thoroughly mixed with the water to be treated to achieve the degradation of organic pollutants; wherein the oxidant is periodate.
[0025] In this embodiment, the periodate is selected from one or more of sodium periodate, potassium periodate, and ammonium periodate.
[0026] In this embodiment, the pretreatment of the crop straw includes: After being crushed, the crop straw is passed through a 40-mesh sieve and placed in a muffle furnace for pyrolysis and carbonization under inert gas protection to obtain biochar.
[0027] In this embodiment, the pyrolysis and carbonization conditions are as follows: heating from 20°C to 350-500°C at a rate of 5-10°C / min for 3-8 hours.
[0028] In this embodiment, the biochar is ground, sieved, and then added to deionized water. The mass-to-volume ratio of the biochar powder obtained after grinding and sieving to the deionized water is 30-50g:480-800mL.
[0029] In this embodiment, the sieving is done through a 100-mesh sieve; the ultrasonic treatment power is 100~200 W, and the time is 30~60 min; the filtration uses a 0.45 μm filter membrane.
[0030] In this embodiment, the pH of the filtrate is adjusted to a preset value of 6.9±0.1.
[0031] In this embodiment, during the thorough mixing of the dissolved black carbon solution and the oxidant with the water to be treated, the concentration of the dissolved black carbon solution is 20~40 mgC / L.
[0032] In this embodiment, the crop straw is selected from at least one of corn straw, peanut straw, sorghum straw, and wheat straw.
[0033] In this embodiment, the organic pollutant includes, but is not limited to, diethyl phthalate.
[0034] Example 1
[0035] After being crushed and passed through a 40-mesh sieve, the corn stalks were placed in a muffle furnace and pyrolyzed and carbonized under the protection of an inert gas (N2). The pyrolysis and carbonization conditions were as follows: the temperature was increased from 20°C to 400°C at a rate of 5°C / min and maintained at this temperature for 3 hours to obtain corn biochar.
[0036] Corn biochar was ground and passed through a 100-mesh sieve to obtain corn biochar powder. 50 g of corn biochar powder was added to 800 mL of deionized water, stirred, and then ultrasonically treated in a water bath ultrasonic instrument at a power of 100 W for 30 min to obtain a suspension.
[0037] The suspension was filtered through a 0.45 μm filter membrane, and the pH of the filtrate was adjusted to 6.9 ± 0.1 to obtain the corn dissolved carbon solution (Corn DBC). The TOC of the corn dissolved carbon solution was determined. The corn dissolved carbon solution needed to be stored in the dark at 4°C before the experiment. During the experiment, its concentration was adjusted to 20 mg C / L.
[0038] An aqueous solution containing 10 ppm diethyl phthalate was prepared as the treatment target for pollutant degradation experiments. The reaction was initiated in a 50 mL Erlenmeyer flask containing a 20 mg / L corn black carbon solution, followed by the addition of 2 mM sodium periodate. Stirring (or other mixing methods) was then performed. All experiments were conducted at room temperature (25 ± 1 °C). Different sampling times were set during the experiments, and the concentration of diethyl phthalate at each sampling time was determined using high-performance liquid chromatography (HPLC).
[0039] Example 2
[0040] After being crushed and passed through a 40-mesh sieve, peanut straw was placed in a muffle furnace and pyrolyzed and carbonized under the protection of an inert gas (N2). The pyrolysis and carbonization conditions were as follows: the temperature was increased from 20°C to 400°C at a rate of 5°C / min and maintained at this temperature for 3 hours to obtain peanut biochar.
[0041] Peanut biochar was ground and passed through a 100-mesh sieve to obtain peanut biochar powder. 50 g of peanut biochar powder was added to 800 mL of deionized water, stirred, and then ultrasonically treated in a water bath ultrasonic instrument at a power of 100 W for 30 min to obtain a suspension.
[0042] The suspension was filtered through a 0.45 μm filter membrane, and the pH of the filtrate was adjusted to 6.9 ± 0.1 to obtain the peanut dissolved carbon solution (Peanut DBC). The TOC of the peanut dissolved carbon solution was determined using TOC. The peanut dissolved carbon solution needed to be stored in the dark at 4°C before the experiment. During the experiment, its concentration was adjusted to 40 mg C / L.
[0043] An aqueous solution containing 10 ppm diethyl phthalate was prepared as the treatment target for pollutant degradation experiments. The reaction was initiated in a 50 mL Erlenmeyer flask containing a peanut black carbon solution containing 40 mg C / L, followed by the addition of 1 mM sodium periodate to start the reaction. Stirring (or other mixing methods) was then performed. All experiments were conducted at room temperature (25 ± 1 °C). Different sampling times were set during the experiments, and the concentration of diethyl phthalate at each sampling time was determined using high-performance liquid chromatography (HPLC).
[0044] Example 3
[0045] After being crushed and passed through a 40-mesh sieve, sorghum stalks were placed in a muffle furnace and pyrolyzed and carbonized under the protection of an inert gas (N2). The pyrolysis and carbonization conditions were as follows: the temperature was increased from 20°C to 400°C at a rate of 5°C / min and maintained at this temperature for 3 hours to obtain sorghum biochar.
[0046] Sorghum biochar was ground and passed through a 100-mesh sieve to obtain sorghum biochar powder. 50 g of sorghum biochar powder was added to 800 mL of deionized water, stirred, and then ultrasonically treated in a water bath ultrasonic instrument at a power of 100 W for 30 min to obtain a suspension.
[0047] The suspension was filtered through a 0.45 μm filter membrane, and the pH of the filtrate was adjusted to 6.9 ± 0.1 to obtain the sorghum dissolved carbon solution (Sorghum DBC). The TOC of the sorghum dissolved carbon solution was determined. The sorghum dissolved carbon solution needed to be stored in the dark at 4°C before the experiment. During the experiment, its concentration was adjusted to 30 mg C / L.
[0048] An aqueous solution containing 10 ppm diethyl phthalate was prepared as the treatment target for pollutant degradation experiments. The reaction was initiated in a 50 mL Erlenmeyer flask containing a 30 mg / L corn black carbon solution, followed by the addition of 2 mM sodium periodate. Stirring (or other mixing methods) was then performed. All experiments were conducted at room temperature (25 ± 1 °C). Different sampling times were set during the experiments, and the concentration of diethyl phthalate at each sampling time was determined using high-performance liquid chromatography (HPLC).
[0049] Comparative Example 1
[0050] An aqueous solution containing 10 ppm diethyl phthalate was prepared as the treatment target for pollutant degradation experiments. The solution was added to a 50 mL Erlenmeyer flask, followed by the addition of 2 mM sodium periodate to initiate the reaction. Stirring (or other homogenization methods) was then employed. All experiments were conducted at room temperature (25 ± 1 °C). Different sampling times were set during the experiments, and the concentration of diethyl phthalate at each sampling time was determined using high-performance liquid chromatography (HPLC).
[0051] Figure 1 The diagram shows the activation of periodate by dissolved black carbon to degrade DEP. Dissolved black carbon can activate periodate to generate reactive oxygen species. Figure 4 The EPR test showed obvious characteristic peaks of hydroxyl radicals, indicating that the degradation process follows the free radical pathway and that hydroxyl radicals are the main reactive oxygen species. Figure 2 The image shows the infrared spectrum and FTICR MS image of the dissolved black carbon prepared in this invention. According to the infrared spectrum, various dissolved black carbons can be found to have significant oxygen- and carbon-containing functional groups. According to the FTICR MS composition diagram, it has abundant lignin and other substances. Figure 3 As shown, compared with Comparative Example 1 which only contained periodate, the solution containing periodate and DBC showed a significantly faster DEP removal efficiency. After 2 hours of reaction, the DEP removal efficiency increased by nearly 50%.
[0052] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive technical essence shall still fall within the protection scope of the present invention.
Claims
1. A method for degrading organic pollutants using dissolved black carbon to activate oxidants, characterized in that, Includes the following steps: Obtain crop straw, pre-treat the crop straw to obtain biochar; The biochar was ground, sieved, and then added to deionized water. The mixture was then stirred and sonicated to obtain a suspension. The suspension is filtered, the filtrate is collected, and the pH of the filtrate is adjusted to a preset value to obtain a dissolved black carbon solution. The dissolved black carbon solution and oxidant are thoroughly mixed with the water to be treated to achieve the degradation of organic pollutants; wherein the oxidant is periodate.
2. The method for degrading organic pollutants using dissolved black carbon activated oxidant according to claim 1, characterized in that, The periodate is selected from one or more of sodium periodate, potassium periodate, and ammonium periodate.
3. The method for degrading organic pollutants using dissolved black carbon activated oxidant according to claim 1, characterized in that, The pretreatment of the crop straw includes: After being crushed, crop straw is passed through a 40-mesh sieve and placed in a muffle furnace for pyrolysis and carbonization under inert gas protection to obtain biochar.
4. The method for degrading organic pollutants using dissolved black carbon activated oxidant according to claim 3, characterized in that, The pyrolysis and carbonization conditions are as follows: heating from 20℃ to 350-500℃ at a rate of 5-10℃ / min for 3-8 hours.
5. The method for degrading organic pollutants using dissolved black carbon activated oxidant according to claim 1, characterized in that, The biochar is ground, sieved, and then added to deionized water. The mass-to-volume ratio of the biochar powder obtained after grinding and sieving to the deionized water is 30-50g:480-800mL.
6. The method for degrading organic pollutants using dissolved black carbon activated oxidant according to claim 1, characterized in that, The sieving is done through a 100-mesh sieve; the ultrasonic treatment power is 100~200 W, and the time is 30~60 min; the filtration uses a 0.45 μm filter membrane.
7. The method for degrading organic pollutants using dissolved black carbon activated oxidant according to claim 1, characterized in that, The pH of the filtrate is adjusted to a preset value of 6.9 ± 0.
1.
8. The method for degrading organic pollutants using dissolved black carbon activated oxidant according to claim 1, characterized in that, In the process of thoroughly mixing the dissolved black carbon solution and the oxidant with the water to be treated, the concentration of the dissolved black carbon solution is 20~40 mgC / L.
9. The method for degrading organic pollutants using dissolved black carbon activated oxidant according to claim 1, characterized in that, The crop straw is selected from at least one of corn straw, peanut straw, sorghum straw, and wheat straw.
10. The method for degrading organic pollutants using dissolved black carbon-activated oxidants according to claim 1, characterized in that, The organic pollutants include, but are not limited to, diethyl phthalate.