CN112516964B - Nitrogen-doped biochar and preparation method and application thereof - Google Patents
Nitrogen-doped biochar and preparation method and application thereof Download PDFInfo
- Publication number
- CN112516964B CN112516964B CN202011280144.9A CN202011280144A CN112516964B CN 112516964 B CN112516964 B CN 112516964B CN 202011280144 A CN202011280144 A CN 202011280144A CN 112516964 B CN112516964 B CN 112516964B
- Authority
- CN
- China
- Prior art keywords
- nitrogen
- doped
- biochar
- bicarbonate
- paper
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
- B01J20/20—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising free carbon; comprising carbon obtained by carbonising processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/24—Nitrogen compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/281—Treatment of water, waste water, or sewage by sorption using inorganic sorbents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/283—Treatment of water, waste water, or sewage by sorption using coal, charred products, or inorganic mixtures containing them
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/725—Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
Abstract
The invention discloses nitrogen-doped biochar and a preparation method and application thereof, wherein the preparation method of the nitrogen-doped biochar comprises the following steps: and putting a part of the regenerated paper into a mixed solution of the nitrogen-doped precursor and the bicarbonate, standing, removing the regenerated paper soaked in the solution and not soaked by the solution, calcining, washing and drying the obtained regenerated paper adsorbed with the nitrogen-doped precursor and the bicarbonate to obtain the nitrogen-doped biochar. The nitrogen-doped biochar has the advantages of low cost, good adsorption performance, high catalytic activity, good stability and the like, is a novel biochar material, can realize efficient degradation of organic pollutants, has good recycling performance, can be recycled for many times, has great advantages in removing organic pollutants in water, and has high use value and good application prospect. The preparation method has the advantages of simple process, convenient operation, low requirements on equipment and reaction parameters and the like, is suitable for large-scale preparation, and is beneficial to industrial application.
Description
Technical Field
The invention belongs to the technical field of materials and the field of advanced oxidation treatment of organic pollutants, relates to nitrogen-doped biochar, and a preparation method and application thereof, and particularly relates to nitrogen-doped biochar prepared from regenerated paper and application of the nitrogen-doped biochar in activating persulfate to degrade organic matters in a water body.
Background
With the rapid development of industrial and agricultural industries and urban economy in modern society, a large amount of organic pollutants enter a sewage treatment plant along with the discharge of industrial wastewater and domestic sewage, and the treatment load of the sewage treatment plant is greatly increased. However, some organic pollutants migrate and are enriched in the natural water environment along with rainwater or surface runoff through pesticides and fertilizers used in agricultural production, and pose a great threat to the natural water ecological environment. Taking 2, 4-dichlorophenol as an example, the compound is mainly used for producing pesticides such as linear phosphorus, herbicide oxadiazon, methyl ester weedicide and the like in the pesticide industry, and is widely applied as an important chemical raw material in the pharmaceutical industry. However, 2, 4-dichlorophenol itself has toxicity, denatures proteins to inactivate cells, and thus seriously impairs human functions. In general, organic pollutants enriched in water environment can enter human bodies through various ways, so that human body dysfunction is caused, and human body health is seriously threatened. Therefore, in the field of environmental remediation, the removal of organic pollutants in water bodies has become an important task. However, many organic pollutants are difficult to be removed by common water treatment technologies, and therefore, the development of water treatment technologies with strong oxidation capability and treatment efficiency is an important requirement in the field of organic pollution removal of water bodies at present.
The adsorption and catalytic oxidation repair technology of organic pollutants in water has been studied deeply at home and abroad, wherein the persulfate advanced oxidation technology has great advantages in the aspect of efficiently degrading organic matters due to the characteristics of high treatment efficiency, low cost, easy operation and the like. A great deal of research shows that the persulfate advanced oxidation technology can efficiently remove various organic matters which are difficult to degrade, such as volatile organic matters, endocrine disruptors, medicines, personal care products, perfluorinated compounds and the like. In general, persulfate is difficult to directly oxidize organic matters, but can generate strong-oxidizing sulfate radicals and hydroxyl radicals after being activated, so that most organic pollutants are degraded and completely mineralized. The main current activation methods are mainly classified into physical methods and chemical methods. The physical method mainly comprises ultraviolet irradiation, heating, ultrasound and the like; the chemical method mainly comprises alkali, phenols, transition metal ions, transition metal oxide activation method and the like. The physical method has high energy consumption, but the transition metal oxide has poor reusability and is easy to cause secondary pollution. From the sustainable development point of view, an environmentally friendly non-metallic catalyst would be a good choice. The non-metal catalyst, especially the carbon material, can completely avoid the problem of secondary pollution of metal ions, and has the advantages of easy separation, environmental friendliness and high stability, and the use of the non-metal catalyst in the activation of persulfate to degrade organic pollutants in water is a good choice, but the catalytic performance of common carbon materials such as graphene, carbon nanotubes and the like still needs to be improved, and the recycling capability is not strong. Therefore, the development of a novel functional carbon material having high catalytic activity and high stability has been promoted.
Biochar is a carbon material derived from biomass as a raw material, and has a very strong application prospect in the aspect of removing environmental pollutants due to the characteristics of wide biomass source, low cost, simple preparation and the like. At present, the catalytic capability of the biochar material in a persulfate advanced oxidation system is weak, which severely limits the wide application of the biochar material. Research shows that heteroatom (such as nitrogen) doping can effectively adjust the catalytic performance of the biochar and enable the biochar to have higher activity, so that the selection of proper raw materials for heteroatom doping modification is an important strategy for developing novel biochar materials. Recycled paper is one kindWaste paperThe paper is produced by the raw materials through more than ten working procedures of sorting, purifying, pulping, papermaking and the like, and is a resource which is visible anywhere in life and is used in large quantity, such as a paper box used in large quantity, a paper tube core of roll paper and the like. A large amount of recycled paper is discarded and recycled every day, so it is a good cheap resource for preparing biochar. The functional biochar material made of the recycled paper accords with the concept of waste resource utilization in the current times. To date, no report on the preparation of biochar by using recycled paper is found.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the defects of the prior art, provide a nitrogen-doped biochar with good adsorption performance, high catalytic activity and good stability and a preparation method thereof, and also provide an application of the nitrogen-doped biochar in removing organic pollutants in a water body.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
a preparation method of nitrogen-doped biochar comprises the following steps:
s1, putting a part of the regenerated paper into a mixed solution of the nitrogen-doped precursor and the bicarbonate, standing, and removing the regenerated paper which is soaked in the solution and is not soaked by the solution to obtain regenerated paper adsorbed with the nitrogen-doped precursor and the bicarbonate;
and S2, calcining, washing and drying the regenerated paper adsorbing the nitrogen-doped precursor and the bicarbonate obtained in the step S1 to obtain the nitrogen-doped biochar.
In the above preparation method, further improvement is provided, in step S1, the mass ratio of the nitrogen-doped precursor to the bicarbonate in the mixed solution of the nitrogen-doped precursor and the bicarbonate is 1: 1; the concentration of the nitrogen-doped precursor in the mixed solution of the nitrogen-doped precursor and the bicarbonate is 50 g/L-70 g/L; the concentration of the bicarbonate in the mixed solution of the nitrogen-doped precursor and the bicarbonate is 50 g/L-70 g/L.
In a further improvement of the above preparation method, in step S1, the nitrogen-doped precursor is thiourea and/or urea; the bicarbonate is at least one of sodium bicarbonate, potassium bicarbonate and ammonium bicarbonate.
In a further improvement of the above preparation method, in step S1, the recycled paper further includes the following steps before use: cutting the recycled paper into strip-shaped paper strips with the width of 1-3 cm, sequentially washing for 2-4 times by using ethanol and water respectively, and drying; the recycled paper is a packaging paper box and/or a paper tube.
In the above preparation method, further improvement is provided, in step S1, the standing time is 15min to 60 min.
In a further improvement of the above preparation method, in step S2, the calcination is performed in a nitrogen atmosphere; the heating rate in the calcining process is 5-8 ℃/min; the calcining temperature is 600-900 ℃; the calcining time is 2-3 h; the washing is 2-4 times by sequentially adopting ethanol and water.
As a general technical concept, the present invention also provides a nitrogen-doped biochar, which is prepared by the above-described preparation method.
As a general technical concept, the invention also provides an application of the nitrogen-doped biochar in removing organic pollutants in a water body.
The application is further improved, and comprises the following steps: mixing nitrogen-doped biochar with water containing organic pollutants, stirring, adding persulfate to perform an oxidative degradation reaction, and removing the organic matters in the water; the mass ratio of the nitrogen-doped biochar to organic pollutants in the water body is 1-8: 1; the mass ratio of the persulfate to the organic pollutants in the water body is 1-20: 1.
In the above applications, further improvement, the persulfate is sodium peroxodisulfate or potassium peroxomonosulfate; the pH value of the water body containing the organic pollutants is 2-11; the organic pollutants in the water body containing the organic pollutants are phenolic pollutants, antibiotic pollutants or dye pollutants; the phenolic pollutant is at least one of bisphenol A, phenol and 2, 4-dichlorophenol; the antibiotic pollutants are tetracycline hydrochloride and/or norfloxacin; the dye pollutant is rhodamine B and/or methyl orange; the rotating speed in the stirring process is 150-300 rpm; the temperature in the stirring process is 15-35 ℃; the stirring time is 60 min-120 min; the temperature in the oxidative degradation treatment process is 15-35 ℃; the time of the oxidative degradation treatment is 60-140 min.
Compared with the prior art, the invention has the advantages that:
(1) the invention provides a preparation method of nitrogen-doped biochar, which is characterized in that regenerated paper is used as a raw material, a nitrogen-doped precursor and bicarbonate are adsorbed into the regenerated paper by utilizing the capillary action of the regenerated paper, wherein the bicarbonate is used as a complexing connector and can complex the nitrogen-doped precursor to the surface of pores of a regenerated paper sheet, and on the basis, the regenerated paper adsorbed with the nitrogen-doped precursor and the bicarbonate is calcined to realize carbonization and nitrogen doping of the regenerated paper, so that the nitrogen-doped biochar is prepared. According to the invention, the pores of the recycled paper can be prevented from being excessively blocked in the nitrogen doping process by utilizing the capillary action, and the catalytic performance is favorably improved. In the invention, the bicarbonate also has the function of corroding the surface of the material, which is beneficial to improving the specific surface area and the electric conductivity of the biochar and is beneficial to successfully doping nitrogen and improving the catalytic performance of the material. The nitrogen-doped biochar prepared by the preparation method has a rough surface and a lamellar structure, has rich nitrogen-doped sites and edge defects due to introduction of nitrogen atoms, such as pyridine nitrogen, pyrrole nitrogen, graphite nitrogen and the like, and can provide rich active sites for adsorption and catalytic degradation of organic matters, so that the nitrogen-doped biochar has high catalytic activity on persulfate, and can realize effective degradation of organic pollutants. The nitrogen-doped biochar has the advantages of low cost, good adsorption performance, high catalytic activity, good stability and the like, is a novel biochar material, can realize efficient degradation of organic pollutants, has good recycling performance, can be recycled for many times, has great advantages in removing organic pollutants in water, and has high use value and good application prospect.
(2) The preparation method of the nitrogen-doped biochar takes the recycled paper as the raw material, has very low cost and accords with the concept of utilization of waste resources, and meanwhile, the preparation method has the advantages of simple process, convenience in operation, low requirements on equipment and reaction parameters and the like, is suitable for large-scale preparation, and is beneficial to industrial application.
(3) The invention also provides application of the nitrogen-doped biochar in removing organic pollutants in water, and particularly relates to the degradation of the organic pollutants in the water by activating persulfate through the nitrogen-doped biochar, the organic pollutants are efficiently adsorbed by utilizing the larger specific surface area of the nitrogen-doped biochar and a plurality of nitrogen-containing and oxygen-containing functional groups, the degradation of the organic pollutants is carried out through the activation effect of the nitrogen-doped biochar on the persulfate, the degradation is carried out through the free radical reaction which is dominated by hydroxyl free radicals generated by activating the persulfate, and singlet oxygen participates in promoting the degradation, so that the degradation of the organic pollutants is fast, and the high-efficiency degradation removal of various organic matters can be realized. Taking 2, 4-dichlorophenol as an example, the adsorption removal rate of the nitrogen-doped biochar on 100mg/L of 2, 4-dichlorophenol can reach 35% within 60min, and the removal rate of the nitrogen-doped biochar on 100mg/L of 2, 4-dichlorophenol can reach 95.7% within 140min after sodium peroxodisulfate is activated. Meanwhile, the method for removing the organic pollutants in the water body has a wide pH application range and has good efficiency in the range of pH 2-11. In addition, for the advanced oxidation technology of general persulfate, the catalyst is easy to deactivate after being used, and when the nitrogen-doped biochar is used as the catalyst in the invention, the removal effect on pollutants can still be kept at 90% after being recycled for 3 times, which is far superior to other technologies. The application method has the advantages of simple operation, high degradation efficiency, short operation period and the like, can efficiently degrade organic pollutants in the water body, and has very important significance for effectively removing toxic and harmful pollutants in the environment.
Drawings
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention.
Fig. 1 is a scanning electron microscope image of nitrogen-doped biochar prepared in example 1 of the present invention.
Fig. 2 is a raman spectrum of the nitrogen-doped biochar prepared in example 1 of the present invention.
Fig. 3 is an X-ray high resolution photoelectron spectrum of N1s of the nitrogen-doped biochar prepared in example 1 of the present invention.
FIG. 4 is a graph showing the degradation effect of sodium peroxodisulfate activated by nitrogen-doped biochar prepared at different temperatures in example 4 of the present invention on 2, 4-dichlorophenol.
FIG. 5 is a graph showing the degradation effect of nitrogen-doped biochar on 2, 4-dichlorophenol in a water body when sodium peroxodisulfate and potassium peroxomonosulfate are respectively activated in example 5 of the present invention.
FIG. 6 is a graph showing the effect of sodium peroxodisulfate activated by nitrogen-doped biochar at different pH values on the degradation of 2, 4-dichlorophenol in a water body according to example 6 of the present invention.
FIG. 7 is a graph showing the effect of sodium peroxodisulfate repeatedly activated by nitrogen-doped biochar on the degradation of 2, 4-dichlorophenol according to example 7 of the present invention.
FIG. 8 is a graph showing the degradation effect of sodium peroxodisulfate activated by nitrogen-doped biochar on 2, 4-dichlorophenol, rhodamine B, methyl orange, and tetracycline hydrochloride in example 8 of the present invention.
Detailed Description
The invention is further described below with reference to the drawings and specific preferred embodiments of the description, without thereby limiting the scope of protection of the invention.
The starting materials and equipment used in the following examples are commercially available. In the following examples, unless otherwise specified, the data obtained are the average of three or more repeated experiments.
Example 1:
a preparation method of nitrogen-doped biochar takes recycled paper as a raw material, bicarbonate as a complexing connector and a nitrogen-doped precursor as a nitrogen source, and the method is prepared by calcining and comprises the following steps:
(1) firstly, cutting a waste paper cylinder in the roll paper into paper strips with the width of 1.5cm, respectively washing the paper strips for 3 times by using ethanol and ultrapure water, and drying the paper strips at 60 ℃ for later use.
(2) A mixed solution was prepared by dissolving 0.9g of urea and 0.9g of sodium hydrogencarbonate in 15mL of ultrapure water (the concentrations of both urea and sodium hydrogencarbonate were 60 g/L). Immersing the lower end of the paper strip in the step (1) for about 1cm in the solution for half an hour, and enabling the solution to be adsorbed to the surface of the paper fiber through capillary force. After the adsorption is completed, the part soaked in the solution is discarded (in the invention, the part soaked in the solution can block the pore structure of the regenerated paper per se, so that the specific surface area and the catalytic performance of the biochar are reduced), and the part wetted by the capillary force at the upper section is collected (the part not wetted at the top end is discarded), namely the regenerated paper adsorbed with the urea and the sodium bicarbonate.
(3) And (3) calcining the regenerated paper obtained in the step (2) in a tubular furnace at the temperature rise rate of 5 ℃/min to 700 ℃ for 2h in the nitrogen atmosphere, respectively washing the ground material with ethanol and ultrapure water for three times, and drying at the temperature of 60 ℃ to obtain the nitrogen-doped biochar.
Scanning Electron Microscope (SEM) imaging observation was performed on the nitrogen-doped biochar prepared in example 1 of the present invention, and the results are shown in fig. 1. The nitrogen-doped biochar has a sheet layer stacking structure and a rough surface, and can provide a large number of attachment sites for adsorption and catalysis of the biochar.
Raman spectrum analysis was performed on the nitrogen-doped biochar prepared in example 1 of the present invention, and the result is shown in fig. 2. In 1360cm-1And 1604cm-1Two distinct peaks are observed, corresponding to the D and G peaks in the carbon material, respectively. The D peak is derived from the disordered structure of the carbon material, while the G peak represents the graphitized sp2 carbon network. The presence of these two peaks indicates that the material is predominantly carbon material. And the strength of the G peak is greater than that of the G peak, which shows that the nitrogen-doped biochar prepared by the invention has higher graphitization degree.
The nitrogen-doped biochar prepared in example 1 of the present invention was subjected to X-ray high resolution photoelectron spectroscopy analysis using N1s, and the results are shown in fig. 3. The high resolution spectrum of N1s can be clearly divided into four peaks corresponding to the four nitrogen species pyridine nitrogen, pyrrole nitrogen, graphite nitrogen and nitrogen oxide at 398.5eV, 400.5eV, 401.6eV and 407.4eV respectively. The abundant nitrogen species show that nitrogen elements are successfully doped into the carbon network of the biochar, namely the preparation method of the nitrogen-doped biochar is effective and feasible, and the abundant nitrogen-containing functional groups can provide a large number of active sites, so that the adsorption and catalytic activity of the biochar are greatly enhanced, and the application of the biochar in the field of environment is facilitated.
Example 2:
a method for preparing nitrogen-doped biochar, which is basically the same as the embodiment 1, and is different from the method only in that: the temperature of calcination in example 2 was 600 ℃.
Example 3:
a method for preparing nitrogen-doped biochar, which is basically the same as the embodiment 1, and is different from the method only in that: the temperature of calcination in example 3 was 800 ℃.
Example 4:
an application of nitrogen-doped biochar in removing organic pollutants in a water body, in particular to a method for degrading 2, 4-dichlorophenol in the water body by activating sodium peroxodisulfate by using nitrogen-doped biochar prepared at different calcining temperatures, which comprises the following steps:
according to the mass ratio of the nitrogen-doped biochar to the 2, 4-dichlorophenol in the solution of 2: 1, the nitrogen-doped biochar prepared in the examples 1-3 is respectively added into 100 mg/L2, 4-dichlorophenol solution, the mixed solution is subjected to adsorption treatment at the oscillation rate of 200rpm for 60min at 25 ℃, after adsorption equilibrium is reached, the sodium peroxodisulfate is added according to the mass ratio of the sodium peroxodisulfate to the 2, 4-dichlorophenol of 20: 1, and the mixed solution is continuously subjected to oxidative degradation treatment at the oscillation rate of 200rpm at 25 ℃ for 140 min. After the treatment is finished, separating the nitrogen-doped biochar from the solution, realizing the recovery of the catalyst and finishing the degradation of the organic 2, 4-dichlorophenol.
In this embodiment, the concentration of the remaining 2, 4-dichlorophenol in the mixed solution is measured by sampling at 0min and 60min of the adsorption reaction and 10min, 20min, 40min, 60min, 80min, 100min, 120min, and 140min of the oxidative degradation reaction, and the removal rates corresponding to different times are calculated.
FIG. 4 is a graph showing the degradation effect of sodium peroxodisulfate activated by nitrogen-doped biochar prepared at different temperatures in example 4 of the present invention on 2, 4-dichlorophenol. As can be seen from fig. 4, the removal rates of 2, 4-dichlorophenol from the nitrogen-doped biochar obtained at the calcination temperatures of 600 ℃, 700 ℃ and 800 ℃ after 60min adsorption and 140min oxidative degradation are 94.3%, 95.7% and 92.8%, respectively, which indicates that the nitrogen-doped biochar obtained by the preparation method of the present invention has a strong catalytic effect on organic matters, and also indicates that the nitrogen-doped biochar prepared by the present invention at different calcination temperatures has high catalytic performance, i.e., has no strict requirement on the temperature during the preparation process, and is beneficial to large-scale production.
Example 5:
an application of nitrogen-doped biochar in removing organic pollutants in a water body, in particular to a method for degrading 2, 4-dichlorophenol in the water body by using nitrogen-doped biochar activated persulfate (sodium peroxodisulfate, potassium peroxomonosulfate), which comprises the following steps:
adding the nitrogen-doped biochar prepared in example 1 into 100 mg/L2, 4-dichlorophenol solution according to the mass ratio of 2: 1 of the nitrogen-doped biochar to 2, 4-dichlorophenol in the solution, carrying out adsorption treatment on the mixed solution at 25 ℃ at an oscillation rate of 200rpm for 60min, respectively adding persulfate (sodium persulfate and potassium hydrogen persulfate) according to the mass ratio of 20: 1 of the persulfate to 2, 4-dichlorophenol after adsorption equilibrium is reached, and continuously carrying out oxidative degradation treatment on the mixed solution at 25 ℃ at the oscillation rate of 200rpm for 140 min. After the treatment is finished, separating the nitrogen-doped biochar from the solution, realizing the recovery of the catalyst and finishing the degradation of the organic 2, 4-dichlorophenol.
In this embodiment, the concentration of the remaining 2, 4-dichlorophenol in the mixed solution is measured by sampling at 0min and 60min of the adsorption reaction and 10min, 20min, 40min, 60min, 80min, 100min, 120min, and 140min of the oxidative degradation reaction, and the removal rates corresponding to different times are calculated. .
FIG. 5 is a graph showing the degradation effect of nitrogen-doped biochar on 2, 4-dichlorophenol in a water body when sodium peroxodisulfate and potassium peroxomonosulfate are respectively activated in example 5 of the present invention. As can be seen from FIG. 5, the removal rate of 2, 4-dichlorophenol is 85.8% within 140min when potassium monopersulfate is activated, and the removal rate is 95.7% within 140min when sodium peroxodisulfate is activated, indicating that the nitrogen-doped biochar of the present invention can effectively activate various persulfates and can achieve effective degradation of organic pollution.
Example 6:
an application of nitrogen-doped biochar in removing organic pollutants in a water body, in particular to a method for degrading 2, 4-dichlorophenol in the water body by activating sodium peroxodisulfate under different pH conditions by using the nitrogen-doped biochar, which comprises the following steps:
according to the mass ratio of the nitrogen-doped biochar to the 2, 4-dichlorophenol in the solution of 2: 1, the nitrogen-doped biochar prepared in example 1 is respectively added into 2, 4-dichlorophenol solutions with pH values of 2.05, 4.03, 6.08, 8.03 and 11.00 (the concentrations of the solutions are all 100mg/L), the mixed solution is subjected to adsorption treatment at 25 ℃ at an oscillation rate of 200rpm for 60min, after adsorption equilibrium is reached, sodium peroxodisulfate is added according to the mass ratio of the sodium peroxodisulfate to the 2, 4-dichlorophenol of 20: 1, and the mixed solution is continuously subjected to oxidative degradation treatment at 25 ℃ at an oscillation rate of 200rpm for 140 min. After the treatment is finished, separating the nitrogen-doped biochar from the solution, realizing the recovery of the catalyst and finishing the degradation of the organic 2, 4-dichlorophenol.
In this embodiment, the concentration of the remaining 2, 4-dichlorophenol in the mixed solution is measured by sampling at 0min and 60min of the adsorption reaction and 10min, 20min, 40min, 60min, 80min, 100min, 120min, and 140min of the oxidative degradation reaction, and the removal rates corresponding to different times are calculated.
FIG. 6 is a graph showing the effect of sodium peroxodisulfate activated by nitrogen-doped biochar at different pH values on the degradation of 2, 4-dichlorophenol in a water body according to example 6 of the present invention. As can be seen from fig. 6, the removal rate of 2, 4-dichlorophenol under acidic conditions was high, and the removal rates of 2, 4-dichlorophenol at pH 2.05, 4.03, and 6.08 were 85.2%, 87.0%, and 95.7%, respectively, within 140 min. Although the removal rate under the alkaline condition is lower than that under the acidic condition, the overall removal rate is still better, when the pH values are respectively 8.03 and 11.00, the removal rates of 2, 4-dichlorophenol within 140min are respectively 76.6 percent and 59 percent, which shows that compared with the traditional Fenton oxidation technology, the method for degrading organic matters in water by activating persulfate through nitrogen-doped biochar has a wide pH application range and is more favorable for application in practical water.
Example 7:
the reusability of the nitrogen-doped biochar is inspected, and specifically comprises the following steps: the method for degrading 2, 4-dichlorophenol in water by repeatedly activating sodium peroxydisulfate by using nitrogen-doped biochar comprises the following steps:
(1) adding the nitrogen-doped biochar prepared in example 1 into a 2, 4-dichlorophenol solution with the concentration of 100mg/L according to the mass ratio of 2: 1 of the nitrogen-doped biochar to 2, 4-dichlorophenol in the solution, carrying out adsorption treatment on the mixed solution at 25 ℃ at the oscillation rate of 200rpm for 60min, after reaching adsorption equilibrium, adding sodium peroxodisulfate according to the mass ratio of 20: 1 of the sodium peroxodisulfate to 2, 4-dichlorophenol, and continuously carrying out oxidative degradation treatment on the mixed solution at 25 ℃ at the oscillation rate of 200rpm for 140 min. After the treatment is finished, separating the nitrogen-doped biochar from the solution, realizing the recovery of the catalyst and finishing the degradation of the organic 2, 4-dichlorophenol.
(2) And (2) filtering the nitrogen-doped biochar in the step (1) to separate the nitrogen-doped biochar from the solution, washing the biochar with ethanol and ultrapure water for three times respectively, and drying the biochar in vacuum at the temperature of 60 ℃. And (3) repeating the process in the step (1) and the process in the step (2) on the dried nitrogen-doped biochar, so as to realize the recycling and utilization of the nitrogen-doped biochar.
In this example, the concentration of the remaining 2, 4-dichlorophenol in the mixed solution was measured by sampling at 0min and 60min of the adsorption reaction and 10min, 20min, 40min, 60min, 80min, 100min, 120min, and 140min of the oxidative degradation reaction, and the removal rate of 2, 4-dichlorophenol corresponding to different times was calculated.
FIG. 7 is a graph showing the effect of sodium peroxodisulfate repeatedly activated by nitrogen-doped biochar on the degradation of 2, 4-dichlorophenol according to example 7 of the present invention. As can be seen from fig. 7, the degradation rates of 2,4 dichlorophenol were 95.7%, 92.8% and 90.0% for the first, second and third uses, respectively. Even if the catalyst is recycled for three times, the catalytic performance of the nitrogen-doped biochar is reduced by 5.7 percent, which shows that the nitrogen-doped biochar prepared by the method has strong repeatability and usability in the persulfate activation process, and the cost in practical application can be greatly saved.
Example 8:
an application of nitrogen-doped biochar in removing organic pollutants in a water body, in particular to a method for degrading various organic matters (2, 4-dichlorophenol, rhodamine B, methyl orange and tetracycline hydrochloride) in the water body by activating sodium peroxydisulfate by using the nitrogen-doped biochar, which comprises the following steps:
adding the nitrogen-doped biochar prepared in example 1 into 100 mg/L2, 4-dichlorophenol solution, 50mg/L rhodamine B solution, 50mg/L methyl orange solution and 50mg/L tetracycline hydrochloride solution respectively according to the mass ratio of the nitrogen-doped biochar to organic matters in the solution of 2: 1, carrying out adsorption treatment on the mixed solution at 25 ℃ at an oscillation rate of 200rpm for 60min, adding sodium peroxodisulfate according to the mass ratio of the sodium peroxodisulfate to the 2, 4-dichlorophenol of 20: 1 after reaching adsorption balance, and continuing carrying out oxidative degradation treatment on the mixed solution at 25 ℃ at the oscillation rate of 200rpm for 140 min. After the treatment is finished, separating the nitrogen-doped biochar from the solution, realizing the recovery of the catalyst and finishing the degradation of the organic 2, 4-dichlorophenol.
In this embodiment, the concentration of the remaining organic matter in the mixed solution is sampled and measured at 0min and 60min of the adsorption reaction and 10min, 20min, 40min, 60min, 80min, 100min, 120min, and 140min of the oxidative degradation reaction, and the removal rates of the organic matter corresponding to different times are calculated.
FIG. 8 is a graph showing the degradation effect of sodium peroxodisulfate activated by nitrogen-doped biochar on 2, 4-dichlorophenol, rhodamine B, methyl orange, and tetracycline hydrochloride in example 8 of the present invention. As can be seen from FIG. 8, the nitrogen-doped biochar activated sodium peroxodisulfate has a good removal effect on various organic matters such as phenols, dyes and antibiotics, and within 140min, the removal rates on 2, 4-dichlorophenol, rhodamine B, methyl orange and tetracycline hydrochloride are respectively 95.7%, 67.5%, 85.3% and 78%. Meanwhile, as can be seen from fig. 8, rhodamine B removal is mainly achieved by adsorption of nitrogen-doped biochar, and methyl orange and tetracycline hydrochloride removal is mainly achieved by oxidative degradation after sodium peroxodisulfate is added. Although the removal effect of different organic pollutants is different, the overall efficiency is very high, which shows that the method for removing the organic pollutants in the water body by using the nitrogen-doped biochar has universality for various organic matters.
The above examples are merely preferred embodiments of the present invention, and the scope of the present invention is not limited to the above examples. All technical schemes belonging to the idea of the invention belong to the protection scope of the invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention, and such modifications and embellishments should also be considered as within the scope of the invention.
Claims (7)
1. The preparation method of the nitrogen-doped biochar is characterized by comprising the following steps of:
s1, putting a part of the regenerated paper into the mixed solution of the nitrogen-doped precursor and the bicarbonate, standing for 15-60 min, and removing the regenerated paper which is soaked in the solution and not soaked by the solution to obtain the regenerated paper adsorbed with the nitrogen-doped precursor and the bicarbonate; the recycled paper further comprises the following treatments before use: cutting the recycled paper into strip-shaped paper strips with the width of 1-3 cm, sequentially washing for 2-4 times by using ethanol and water respectively, and drying; the recycled paper is a packaging paper box and/or a paper tube; the bicarbonate is sodium bicarbonate; the mass ratio of the nitrogen-doped precursor to the bicarbonate in the mixed solution of the nitrogen-doped precursor and the bicarbonate is 1: 1; the nitrogen-doped precursor is thiourea and/or urea;
and S2, calcining, washing and drying the regenerated paper adsorbing the nitrogen-doped precursor and the bicarbonate obtained in the step S1 to obtain the nitrogen-doped biochar.
2. The method according to claim 1, wherein in step S1, the concentration of the nitrogen-doped precursor in the mixed solution of the nitrogen-doped precursor and the bicarbonate is 50 to 70 g/L; the concentration of the bicarbonate in the mixed solution of the nitrogen-doped precursor and the bicarbonate is 50 g/L-70 g/L.
3. The production method according to claim 1 or 2, characterized in that, in step S2, the calcination is performed under a nitrogen atmosphere; the heating rate in the calcining process is 5-8 ℃/min; the calcining temperature is 600-900 ℃; the calcining time is 2-3 h; the washing is 2-4 times by sequentially adopting ethanol and water.
4. A nitrogen-doped biochar, which is prepared by the preparation method of any one of claims 1-3.
5. Use of the nitrogen-doped biochar of claim 4 in removing organic contaminants from a body of water.
6. Use according to claim 5, characterized in that it comprises the following steps: mixing nitrogen-doped biochar with water containing organic pollutants, stirring, adding persulfate to perform an oxidative degradation reaction, and removing the organic matters in the water; the mass ratio of the nitrogen-doped biochar to organic pollutants in the water body is 1-8: 1; the mass ratio of the persulfate to the organic pollutants in the water body is 1-20: 1.
7. Use according to claim 6, wherein the persulfate is sodium peroxodisulfate or potassium peroxomonosulfate; the pH value of the water body containing the organic pollutants is 2-11; the organic pollutants in the water body containing the organic pollutants are phenolic pollutants, antibiotic pollutants or dye pollutants; the phenolic pollutant is at least one of bisphenol A, phenol and 2, 4-dichlorophenol; the antibiotic pollutants are tetracycline hydrochloride and/or norfloxacin; the dye pollutant is rhodamine B and/or methyl orange; the rotating speed in the stirring process is 150-300 rpm; the temperature in the stirring process is 15-35 ℃; the stirring time is 60 min-120 min; the temperature in the oxidative degradation treatment process is 15-35 ℃; the time of the oxidative degradation treatment is 60-140 min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011280144.9A CN112516964B (en) | 2020-11-16 | 2020-11-16 | Nitrogen-doped biochar and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011280144.9A CN112516964B (en) | 2020-11-16 | 2020-11-16 | Nitrogen-doped biochar and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112516964A CN112516964A (en) | 2021-03-19 |
| CN112516964B true CN112516964B (en) | 2022-04-26 |
Family
ID=74981444
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011280144.9A Active CN112516964B (en) | 2020-11-16 | 2020-11-16 | Nitrogen-doped biochar and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112516964B (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113967462A (en) * | 2021-06-10 | 2022-01-25 | 南通大学 | Preparation method and application of waste paperboard biochar |
| CN113578269A (en) * | 2021-08-30 | 2021-11-02 | 南通大学 | Waste paperboard biochar for treating rhodamine B dye wastewater and preparation method and application thereof |
| CN113979435A (en) * | 2021-11-17 | 2022-01-28 | 厦门理工学院 | Biochar and application thereof in catalyzing sodium persulfate to degrade 4-chlorophenol |
| CN114570331A (en) * | 2022-03-31 | 2022-06-03 | 陕西科技大学 | Nitrogen-doped porous nano biochar, and preparation method and application thereof |
| CN114950521B (en) * | 2022-04-12 | 2023-10-13 | 湖南大学 | Mn-N-C site-containing algae-based carbon catalyst and preparation method and application thereof |
| CN114768766B (en) * | 2022-05-24 | 2024-01-19 | 浙江树人学院 | Preparation method and application of nitrogen-doped carbon nanotube coated cobalt-iron-manganese nanoparticle modified biochar |
| CN115400778A (en) * | 2022-08-19 | 2022-11-29 | 中国科学院山西煤炭化学研究所 | Porous magnetic iron-nitrogen carbon and preparation method and application thereof |
| CN115414958A (en) * | 2022-09-26 | 2022-12-02 | 吉林大学 | Melamine-doped biochar material and application thereof |
| CN115837288B (en) * | 2022-11-18 | 2024-04-23 | 南京林业大学 | Preparation and application of nitrogen-doped porous bowl-shaped carbon catalyst with ultrahigh active site exposure rate |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105271227A (en) * | 2015-11-25 | 2016-01-27 | 江苏大学 | Preparation method for porous carbon material with high specific surface area |
| CN106356517A (en) * | 2016-10-28 | 2017-01-25 | 华南理工大学 | Plant biomass carbon doped sulfur-nitrogen composite material of cathode of sodium ion battery and lithium ion battery and preparation method of plant biomass carbon doped sulfur-nitrogen composite material |
| CN106732361A (en) * | 2016-12-21 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the sludge base charcoal of the paper powder that adulterates |
| CN106784704A (en) * | 2016-12-27 | 2017-05-31 | 陕西科技大学 | A kind of preparation method of N doping charcoal carbon negative pole material |
| CN106865540A (en) * | 2017-03-24 | 2017-06-20 | 桂林电子科技大学 | A kind of N doping loose structure carbon material and its preparation method and application |
| CN109767927B (en) * | 2019-01-17 | 2020-05-08 | 中南大学 | Preparation method of high-performance nitrogen-doped biomass porous carbon for supercapacitor |
| CN110483018A (en) * | 2019-09-24 | 2019-11-22 | 南京路通工程科技有限公司 | A kind of preparation method of bed mud haydite |
| CN110743588A (en) * | 2019-10-10 | 2020-02-04 | 西安建筑科技大学 | Nitrogen-doped biochar catalytic material as well as preparation method and application thereof |
| CN110668438A (en) * | 2019-11-28 | 2020-01-10 | 长江师范学院 | Novel porous carbon electrode material for capacitive deionization technology and application thereof |
| CN112023879A (en) * | 2020-08-04 | 2020-12-04 | 中山大学 | Preparation method and application of porous carbon material |
-
2020
- 2020-11-16 CN CN202011280144.9A patent/CN112516964B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112516964A (en) | 2021-03-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112516964B (en) | Nitrogen-doped biochar and preparation method and application thereof | |
| CN112121766B (en) | Ramie fiber-based biochar and preparation method and application thereof | |
| CN106076335B (en) | A kind of preparation method and application of heterogeneous Fenton catalyst | |
| CN110743588A (en) | Nitrogen-doped biochar catalytic material as well as preparation method and application thereof | |
| CN112516963B (en) | Sesame core charcoal and preparation method and application thereof | |
| CN112441659A (en) | Method for degrading and treating organic pollutants by activating persulfate through multi-stage mesoporous biochar material | |
| CN110606539B (en) | Method for treating organic wastewater by utilizing sludge resource | |
| CN104084185A (en) | Modified activated carbon as well as preparation method and application thereof | |
| CN115007208B (en) | Preparation method and application of graphene/cellulose aerogel-based composite photocatalyst | |
| Yang et al. | Polyaniline derived carbon membrane and its in-situ membrane fouling mitigation performance in MBR based on metal-free electro-Fenton | |
| CN112387271B (en) | Carbon-coated manganous-manganic oxide composite material and preparation method and application thereof | |
| CN113441142A (en) | Preparation method and application of oxygen vacancy-rich graphene-loaded porous nano ferroelectric oxide catalyst | |
| CN116174009B (en) | Nitrogen-sulfur doped porous carbon catalyst and application thereof | |
| CN113134347A (en) | Preparation method and application of heteroatom porous carbon | |
| CN116078797A (en) | Method for recycling biogas residues | |
| CN112915990B (en) | Coal gangue in-situ carbon activation material and preparation method and application thereof | |
| CN115041166A (en) | Heterogeneous persulfate catalyst and preparation method and application thereof | |
| CN114272895A (en) | Nitrogen-sulfur-phosphorus co-doped ordered porous biochar and preparation method and application thereof | |
| CN116920853A (en) | Wet oxidation catalyst and preparation method and application thereof | |
| CN103030243A (en) | Method for treating methyl naphthol waste water by ferric-carbon micro-electrolysis and TiO2/gamma-Al2O3 catalyst | |
| CN108046381B (en) | Electro-catalytic permeable wall reaction device for industrial wastewater treatment | |
| CN110282703A (en) | A kind of preparation of self-supporting MnOx/LSC three-dimensional combination electrode and its application in mineralising persistent organic pollutants | |
| CN114229984B (en) | Two-stage Fenton-like treatment method for landfill leachate | |
| CN108126726B (en) | Flexible large-area Ta3N5Nano-rod array carbon fiber cloth and preparation method thereof | |
| CN107162097B (en) | Selective photoelectrocatalysis removal method of low-concentration 17 beta-estradiol in coexisting system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |