CN111111612B - Preparation and use method of magnetic porous biochar for removing chromium in water - Google Patents

Preparation and use method of magnetic porous biochar for removing chromium in water Download PDF

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CN111111612B
CN111111612B CN201911319646.5A CN201911319646A CN111111612B CN 111111612 B CN111111612 B CN 111111612B CN 201911319646 A CN201911319646 A CN 201911319646A CN 111111612 B CN111111612 B CN 111111612B
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water
biochar
chromium
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adsorbent
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CN111111612A (en
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孙奇娜
刘欣超
贾清川
张庆瑞
韩梦星
牛一卉
李才才
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Yanshan University
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    • 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
    • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
    • B01J20/28002—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their physical properties
    • B01J20/28009—Magnetic properties
    • 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
    • B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
    • B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
    • 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
    • C02F1/48—Treatment of water, waste water, or sewage with magnetic or electric fields
    • C02F1/488—Treatment of water, waste water, or sewage with magnetic or electric fields for separation of magnetic materials, e.g. magnetic flocculation
    • 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
    • C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
    • 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
    • B01J2220/00—Aspects relating to sorbent materials
    • B01J2220/40—Aspects relating to the composition of sorbent or filter aid materials
    • B01J2220/48—Sorbents characterised by the starting material used for their preparation
    • B01J2220/4875—Sorbents characterised by the starting material used for their preparation the starting material being a waste, residue or of undefined composition
    • B01J2220/4881—Residues from shells, e.g. eggshells, mollusk shells
    • 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
    • C02F2101/10—Inorganic compounds
    • C02F2101/20—Heavy metals or heavy metal compounds
    • C02F2101/22—Chromium or chromium compounds, e.g. chromates
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/10—Biofuels, e.g. bio-diesel

Abstract

The invention discloses a preparation and use method of magnetic porous biochar for removing chromium in water, which is characterized in that Fe (III) is used as a magnetic precursor, and through a method of slow pyrolysis after impregnation and loading and in-situ carbon reduction, artemia egg shells are prepared into the magnetic porous biochar which can be used for removing Cr (VI) and Cr (III) in water.

Description

Preparation and use method of magnetic porous biochar for removing chromium in water
Technical Field
The invention relates to an adsorbent for removing heavy metal in water, in particular to magnetic porous biochar for removing chromium, and belongs to a water body heavy metal pollution treatment technology.
Background
As chromium salt production, tanning, electroplating, wood preservation, dye printing and dyeing and industrial production activities of rubber and ceramics are carried out, a large amount of chromium-containing wastewater is generated, wherein chromium mainly exists in the form of chromate and dichromate. Cr (vi) enters the human body through skin contact, the respiratory system and the digestive system, and is transported to organs such as liver and kidney through blood to cause toxic accumulation, damage to kidney function, DNA damage and canceration. Cr (III) has certain toxicity to aquatic organisms, and can also show toxic reaction to human cells under high dosage.
The technology for removing chromium from water mainly comprises an ion exchange method, a membrane separation method, an adsorption method, a chemical precipitation method, a photocatalysis method and the like. The adsorption method is simple to operate and is already applied to chromium removal. However, since cr (vi) and cr (iii) have opposite charges in water, the effect of the adsorbent on removing two types of chromium ions simultaneously needs to be improved.
The biochar is mainly obtained by a method of pyrolyzing biomass at high temperature in a low-oxygen or oxygen-free environment, mainly consists of aromatic hydrocarbon and simple substance carbon or carbon with a graphite structure, and has lower cost compared with other synthetic adsorbents. Phosphoric acid is used as an activator to synthesize mango seed biochar with the Cr (VI) adsorption amount of 7.8mg/g, phosphoric acid is used as an activator, and FeCl3、AlCl3、MnCl2The adsorption capacity of the biochar synthesized by using the apple peel as an auxiliary activator is increased to 24mg/g, and the adsorption capacity of the biochar synthesized by using the apple peel as a raw material can reach 36.01mg/g, but the adsorption capacity of the biochar on chromium is not high on the whole[1-3]。
Artemia cysts are the shells of dormant eggs laid by artemia by oviposition and are discarded as waste in aquaculture. The artemia cysts have a unique tapered pore passage structure, and the inner layer pore passage is a nano hole, so that the distribution of nano particles can be promoted, and the artemia cysts have a microporous nano template effect; the pore canal of the outer layer is a macropore, which greatly improves the absorption mass transfer efficiency and has macropore reinforced mass transfer effect[4]. The egg shell is directly modified or loaded with nano particles, and can be used as an adsorbent for separating phosphate radicals and heavy metal cations in water[4,5]. The special pore structure of the egg shell can be carbonized to prepare the super capacitor and other electrochemical materials[6-9]After carbonization, the stability of the egg shell in a high-alkaline environment can be improved. However, no disclosure is available for preparing biochar from egg shellsA technique for separating chromium from water.
The application of the iron element in the field of treating chromium pollution of water has been reported. The iron oxide has certain adsorption capacity to Cr (VI)[10](ii) a The iron is loaded on the carrier in a cation form, which is favorable for improving the surface potential of the carrier material and promoting the electrostatic adsorption of Cr (VI) in water[11](ii) a In particular to nano zero-valent iron, which has been one of the research hotspots for removing chromium in recent years, the excellent effect of removing Cr (VI) can be attributed to adsorption and reduction[12]. However, the preparation of the nano zero-valent iron usually needs additional reducing agent, and the finished product has active chemical property, is easy to agglomerate and inactivate and is difficult to recover.
Reference documents:
[1]RAI M K, SHAHI G, MEENA V, et al. Removal of hexavalent chromium Cr(VI) using activated carbon prepared from mango kernel activated with H3PO4[J]. Resource-Efficient Technologies, 2016, 2: S63-S70.
[2]SUN Y, YUE Q, MAO Y,et al. Enhanced adsorption of chromium onto activated carbon by microwave-assisted H3PO4mixed with Fe/Al/Mn activation[J]. J Hazard Mater, 2014, 265:191-200.
[3]ENNIYA I, RGHIOUI L, JOURANI A. Adsorption of hexavalent chromium in aqueous solution on activated carbon prepared from apple peels[J]. Sustainable Chemistry and Pharmacy, 2018, 7:9-16.
[4] Manchu-Yingqi-carrying zirconia biological composite material preparation and phosphate adsorption performance research [ D ], Yanshan university, 2014.
[5] Study on characteristics of heavy metals in deep purified water by zirconium-based biological nano material [ D ], Yanshan university 2015.
[6] Ran Wei, preparation of carbon materials based on artemia cysts and study of electrochemical properties of supercapacitors [ D ], Yanshan university, 2014.
[7]ZHAO Y, HE Y, HE J, et al. Hierarchical porous TiO2templated from natural Artemia cyst shells for photocatalysis applications[J]. RSC Adv, 2014, 4(39): 20393-7.
[8]ZHAO Y, RAN W, HE J, et al. High-performance asymmetric supercapacitors based on multilayer MnO2 /graphene oxide nanoflakes and hierarchical porous carbon with enhanced cycling stability [J]. Small, 2015, 11(11): 1310-9.
[9]ZHAO Y, RAN W, HE J, et al.Oxygen-rich hierarchical porous carbon derived from artemia cyst shells with superior electrochemical performance [J]. ACS Appl Mater Interfaces, 2015, 7(2): 1132-9.
[10] Zhengchao, Pengliptin, Yangjiwen, etc. the nano ferric oxide catalyzes citric acid to reduce Cr (VI) and the significance of the soil environment [ J ]. environmental chemistry, 2016 (11): 2370-6.
[11] Liu Rui, Fe-C-Zeolite for treating groundwater pollution [ D ], Liaoning university, 2018.
[12] Duncaoqiang, green tea extract synthesized charcoal loaded with nano zero-valent iron to repair hexavalent chromium polluted groundwater [ D ], Taiyuan university, 2018.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a preparation and application method of magnetic porous biochar for removing chromium in water, wherein the biochar is prepared from aquatic industry wastes and can coexist with ions (Cl)-、NO3 -Or SO4 2-) Separating Cr (VI) and Cr (III) from the water under the interference of (1).
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
a preparation method of magnetic porous biochar for removing chromium in water takes Fe (III) as a magnetic precursor, and prepares artemia cysts into the magnetic porous biochar by a method of slow pyrolysis and in-situ carbon reduction after impregnation and loading.
The technical scheme of the invention is further improved as follows: the biomass raw material of the biochar is artemia cysts; the magnetism is derived from nano Fe3O4The particle and the precursor are Fe (III), nano Fe3O4The average particle size of the particles is 70nm and the particles are uniformly distributed in a microscopic multilevel pore channel structure with the pore diameter of 200nm-2 mu m.
The technical scheme of the invention is further improved as follows: the method comprises the following specific steps:
A. cleaning artemia egg shell with ethanol solution, drying, and soaking in FeCl3Stirring the solution for 24 hours at 25 ℃, filtering and taking out the solid, and drying the solid at 60 ℃;
B. putting the dried solid in a tubular furnace, introducing nitrogen for protection, and heating for slow pyrolysis and in-situ carbon reduction;
C. and cooling the material subjected to pyrolysis reduction to room temperature, grinding, washing with deionized water to remove impurities, and drying at 60 ℃ to obtain the magnetic porous biochar.
The technical scheme of the invention is further improved as follows: FeCl in the step A3The concentration of the solution is 1mol/L, the artemia egg shell and FeCl3The ratio of the solutions was 1 g: 40 mL.
The technical scheme of the invention is further improved as follows: and the temperature rise rate in the step B is 12.5 ℃/min, the pyrolysis temperature is 450 ℃, and the time is 5 h.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the use method of the magnetic porous biochar for removing chromium from water is characterized in that the magnetic porous biochar can be reused and can remove Cr (VI) and Cr (III) in water.
The technical scheme of the invention is further improved as follows: the method comprises the following specific steps:
firstly, putting a certain amount of magnetic porous biochar serving as an adsorbent into chromium-containing water, and oscillating and adsorbing for a period of time;
separating the adsorbent;
thirdly, the separated adsorbent is placed in NaOH solution for regeneration for a period of time and then can be used for removing chromium in water again.
The technical scheme of the invention is further improved as follows: in the step I, 0.5g of adsorbent is added into 1.0L of chromium-containing water, the water temperature is controlled to be 20-60 ℃, the pH value is controlled to be 1-7, and the oscillation adsorption time is 24 hours.
The technical scheme of the invention is further improved as follows: the separation method of the adsorbent in the step (II) is magnetic separation or standing precipitation.
The technical scheme of the invention is further improved as follows: in the third step, the concentration of NaOH is 0.1mol/L, and the regeneration time is 24 h.
Due to the adoption of the technical scheme, the invention has the technical progress that:
1. the biomass raw material for preparing the biochar is the artemia cysts which are broken after hatching, belongs to waste in the aquatic product industry, is low in cost, and can realize waste utilization; the magnetism of the biochar is derived from nano Fe3O4The precursor is Fe (III) salt, part of Fe (III) is reduced to Fe (II) by the generated carbon in situ in the slow pyrolysis process of the egg shell, other reducing agents are not required to be additionally added, and the preparation method is simple.
2. Multilevel pore channel structure, carbon skeleton, surface functional group and nano Fe of magnetic porous biochar3O4The synergistic effect between the two components makes the adsorbent to coexist with ions (Cl)-、NO3 -Or SO4 2-) The method can efficiently remove chromium in water under the interference, improve the problems of low chromium adsorption capacity and poor selectivity of carbon materials, and enable the adsorbent to be easily separated:
1) the multilevel pore channel structure ensures that the magnetic nano Fe3O4The particles are uniformly dispersed in the material, the mass transfer of target pollutants is promoted, and more effective sites are provided for chromium removal;
2) magnetic nano Fe3O4Besides the electrostatic adsorption effect on Cr (VI), the particles can also improve the surface potential of the material, are beneficial to the enrichment of Cr (VI) on the adsorption surface, and can provide a complexing site for Cr (III) to promote the removal of Cr (III);
3) in a neutral environment, Cr (III) and Fe (III) generate difficultly soluble hydroxide through coprecipitation;
4) during the chromium removal process, carbon and Fe (II) in the adsorbent are used as electron donors and can reduce Cr (VI) into Cr (III), so that the toxicity is reduced, and the Cr (III) continuously acts with the adsorbent to be removed from the aqueous solution.
Drawings
FIG. 1 is a surface topography of a magnetic porous biochar obtained in one embodiment of the invention;
FIG. 2 shows the nano Fe on the magnetic porous charcoal obtained in the first embodiment of the present invention3O4Characteristic diffraction peak of XRD.
Detailed Description
The present invention is further illustrated in detail below with reference to examples:
a preparation method of magnetic porous biochar for removing chromium in water takes Fe (III) as a magnetic precursor, and prepares artemia cysts into the magnetic porous biochar by a method of slow pyrolysis and in-situ carbon reduction after impregnation and loading.
The biomass raw material of the biochar is artemia cysts, belongs to waste in the aquatic product industry, is low in cost, and can realize waste utilization; magnetic source is nano Fe3O4Particles of nano Fe3O4The average particle size of the shell is about 70nm, the precursor of the shell is Fe (III), part of Fe (III) is reduced to Fe (II) in situ by the generated carbon in the slow pyrolysis process of the egg shell, other reducing agents do not need to be additionally added, and the preparation method is simple;
the porous structure is a microscopic multilevel pore channel structure with the pore diameter of 200nm-2 mu m and nano Fe3O4The particles are uniformly distributed in the multilevel pore canal. Multilevel pore canal structure, carbon skeleton, surface functional group and nano Fe of magnetic porous biochar3O4The synergistic effect between the two makes the adsorbent efficiently remove chromium in water under the interference of coexisting ions, improves the problems of low chromium adsorption capacity and poor selectivity of the carbon material, and makes the adsorbent easy to separate:
1) the multilevel pore channel structure ensures that the magnetic nano Fe3O4The particles are uniformly dispersed in the material, the mass transfer of target pollutants is promoted, and more effective sites are provided for chromium removal;
2) magnetic nano Fe3O4Besides the electrostatic adsorption effect on Cr (VI), the particles can also improve the surface potential of the material, are beneficial to the enrichment of Cr (VI) on the adsorption surface, and can provide complexing sites for Cr (III) and promote the enrichment of Cr (II)I) Removing;
3) in a neutral environment, Cr (III) and Fe (III) generate difficultly soluble hydroxide through coprecipitation;
4) during the chromium removal process, the carbon and Fe (II) in the adsorbent are used as electron donors to reduce Cr (VI) into Cr (III), so that the toxicity is reduced, and the Cr (III) continues to act with the adsorbent to be removed from the aqueous solution.
The preparation method comprises the following specific steps:
A. cleaning artemia egg shell with ethanol solution, drying, and soaking in 1mol/L FeCl3In solution, artemia cysts and FeCl3The ratio of the solutions was 1 g: 40mL, stirring for 24 hours at 25 ℃, filtering, taking out the solid, and drying at 60 ℃;
B. placing the dried solid in a tubular furnace, introducing nitrogen for protection, heating for slow pyrolysis and in-situ carbon reduction, wherein the heating rate is 12.5 ℃/min, the pyrolysis temperature is 450 ℃, and the time is 5 h;
C. and cooling the material subjected to pyrolysis reduction to room temperature, grinding, washing with deionized water to remove impurities, and drying at 60 ℃ to obtain the magnetic porous biochar.
The magnetic porous biochar can be reused and can remove Cr (VI) and Cr (III) in water, and the using method comprises the following specific steps:
firstly, putting a certain amount of magnetic porous biochar serving as an adsorbent into chromium-containing water, controlling the water temperature at 20-60 ℃, controlling the pH at 1-7, and oscillating for 24 hours for adsorption;
wherein the adding amount of the adsorbent is 0.5g of the adsorbent added into 1.0L of chromium-containing water;
secondly, separating the adsorbent by a magnetic separation or standing precipitation method;
thirdly, the separated adsorbent is placed in 0.1mol/L NaOH solution for regeneration for 24 hours, and then the adsorbent can be used for removing chromium in water again.
The first embodiment is as follows:
weighing 5g of artemia cysts washed by ethanol solution, and soaking in 200mL of 1mol/L FeCl3The solution was stirred at 25 ℃ for 24h, after which the solid was filtered off and dried at 60 ℃.
And (3) putting the dried solid in a tubular furnace, introducing nitrogen for protection, heating to 450 ℃ at the heating rate of 12.5 ℃/min, keeping the temperature for 5 hours, and stopping heating to finish the processes of slow pyrolysis and in-situ carbon reduction.
And after the material is cooled to room temperature, grinding and washing with deionized water, and drying at 60 ℃ to obtain the magnetic porous biochar.
As shown in figure 1, the magnetic porous biochar keeps a complete multi-stage pore channel structure, nanoparticles are uniformly distributed in the pore channels, and iron is reduced on the surface of the biochar by Fe through slow pyrolysis and in-situ carbon reduction3O4The form exists, and the XRD characteristic diffraction peak is shown in figure 2.
Example two:
taking 0.025 g of the magnetic porous biochar prepared in the first example, adding K with the initial concentration of Cr (VI) of 50mg/L2Cr2O7In solution, the volume of the solution was 50 mL, and the pH was adjusted to 2.0 with NaOH and HCl. The system was shaken at 160rpm for 24h at 25 ℃. After the reaction is finished, magnetically separating the biochar, and measuring the concentration of the residual chromium ions in the liquid phase by using a diphenylcarbodihydrazide spectrophotometry to obtain that the adsorption quantity of Cr (VI) is 143.89mg/g and the removal rate is 94.26 percent respectively.
Example three:
taking 0.025 g of the magnetic porous biochar prepared in the first example, adding K with the initial concentration of Cr (VI) of 50mg/L2Cr2O7In solution, the volume of the solution was 50 mL, and the pH was adjusted to 5.0 with NaOH and HCl. The system was shaken at 160rpm for 24h at 25 ℃. After the reaction is finished, the biochar is magnetically separated, the concentration of the residual chromium ions in the liquid phase is measured by a diphenylcarbodihydrazide spectrophotometry, the adsorption quantity of Cr (VI) is calculated to be 68.78mg/g, and the removal rate is 66.95%.
Example four:
taking 0.025 g of the magnetic porous biochar prepared in the first example, adding K with the initial concentration of Cr (VI) of 50mg/L2Cr2O7In solution, the volume of the solution was 50 mL, and the pH was adjusted to 7.0 with NaOH and HCl. The above system is operated at a speed of 160rpm at 25 DEG CAnd oscillating for 24 hours. After the reaction is finished, standing until the biochar naturally sinks to the bottom, and measuring the concentration of the residual chromium ions in the liquid phase by using a diphenylcarbodihydrazide spectrophotometry to obtain the adsorption quantity of Cr (VI) of 33.67mg/g and the removal rate of 34.73 percent.
Example five:
taking 0.025 g of the magnetic porous biochar prepared in the first example, adding K with the initial concentration of Cr (VI) of 50mg/L2Cr2O7KCl mixed solution with initial concentration molar ratio of Cr (VI) to Cl-=1:64, solution volume 50 mL, and pH adjusted to 2.0 with NaOH and HCl. The system was shaken at 160rpm for 24h at 25 ℃. After the reaction is finished, the biochar is magnetically separated, the concentration of the residual chromium ions in the liquid phase is measured by a diphenylcarbodihydrazide spectrophotometry, the adsorption quantity of Cr (VI) is calculated to be 129.75 mg/g, and the removal rate is 86.07%.
Example six:
taking 0.025 g of the magnetic porous biochar prepared in the first example, adding K with the initial concentration of Cr (VI) of 50mg/L2Cr2O7、K2SO4The initial molar ratio of Cr (VI) to SO in the mixed solution4 2-=1:64, solution volume 50 mL, and pH adjusted to 2.0 with NaOH and HCl. The system was shaken at 160rpm for 24h at 25 ℃. After the reaction is finished, magnetically separating the biochar, and measuring the concentration of the residual chromium ions in the liquid phase by using a diphenylcarbodihydrazide spectrophotometry to obtain that the adsorption quantity of Cr (VI) is 89.78mg/g and the removal rate is 74.96 percent respectively.
Example seven:
taking 0.025 g of the magnetic porous biochar prepared in the first example, adding K with the initial concentration of Cr (VI) of 50mg/L2Cr2O7、KNO3The initial molar ratio of Cr (VI) to NO in the mixed solution3 -=1:64, solution volume 50 mL, and pH adjusted to 2.0 with NaOH and HCl. The system was shaken at 160rpm for 24h at 25 ℃. After the reaction is finished, standing until the biochar naturally sinks to the bottom, measuring the concentration of the residual chromium ions in the liquid phase by using a diphenylcarbazide spectrophotometry, and calculating to obtain the adsorption quantity of Cr (VI) of 121.75 mg/g and the removal rateThe content was 83.85%.
Example eight:
the separated magnetic porous biochar in example II was put into 50 mL of 0.1mol/L NaOH solution and shaken at 160rpm at 25 ℃ for 24 hours. Standing until the biochar naturally settles to the bottom, then pouring out supernatant, and drying the residual mixture at 60 ℃ to obtain regenerated magnetic porous biochar.
Example nine:
taking 0.020g of magnetic porous biochar after the eight examples are regenerated, adding K with the initial concentration of Cr (VI) of 50mg/L2Cr2O7In solution, the volume of the solution was 40mL, and the pH was adjusted to 2.0 with NaOH and HCl. The system is characterized in that the residual rotating speed of the liquid phase is measured by diphenylcarbodihydrazide spectrophotometry for 24h at the temperature of 25 ℃ and the rpm of the charcoal. After the reaction is finished, magnetically separating the biochar, and measuring the concentration of the residual chromium ions in the liquid phase by using a diphenylcarbodihydrazide spectrophotometry to calculate that the removal rate of Cr (VI) is 67.69%. Thus, it can be seen that: the magnetic porous biochar prepared by the invention can be repeatedly used, but the removal effect of the regenerated magnetic porous biochar is reduced, and compared with the two examples, the removal rate of the regenerated biochar to Cr (VI) is 71.83% of that before regeneration.

Claims (6)

1. A preparation method of magnetic porous biochar for removing chromium in water is characterized by comprising the following steps: fe (III) is used as a magnetic precursor, and artemia cysts are prepared into magnetic porous biochar by a method of slow pyrolysis and in-situ carbon reduction after impregnation and loading;
the biomass raw material of the biochar is artemia cysts; the magnetism is derived from nano Fe3O4The particle and the precursor are Fe (III), nano Fe3O4The average particle size of the particles is 70nm and the particles are uniformly distributed in a microscopic multistage pore channel structure with the pore diameter of 200nm-2 mu m;
the method comprises the following specific steps:
A. cleaning artemia egg shell with ethanol solution, drying, and soaking in FeCl3Stirring the solution for 24 hours at 25 ℃, filtering and taking out the solid, and drying the solid at 60 ℃;
B. putting the dried solid in a tubular furnace, introducing nitrogen for protection, and heating for slow pyrolysis and in-situ carbon reduction;
C. cooling the material subjected to pyrolysis reduction to room temperature, grinding, washing with deionized water to remove impurities, and drying at 60 ℃ to obtain magnetic porous biochar;
FeCl in the step A3The concentration of the solution is 1mol/L, the artemia egg shell and FeCl3The ratio of the solutions was 1 g: 40 mL;
and the temperature rise rate in the step B is 12.5 ℃/min, the pyrolysis temperature is 450 ℃, and the time is 5 h.
2. The use method of the magnetic porous biochar prepared by the preparation method according to claim 1 is characterized in that: the magnetic porous biochar can be repeatedly used and can coexist with Cl ions-、NO3 -Or SO4 2-The Cr (VI) and the Cr (III) in the water can be efficiently removed at the same time under the condition of 64 times of concentration.
3. Use according to claim 2, characterized in that: the method comprises the following specific steps:
firstly, putting a certain amount of magnetic porous biochar serving as an adsorbent into chromium-containing water, and oscillating and adsorbing for a period of time;
separating the adsorbent;
thirdly, the separated adsorbent is placed in NaOH solution for regeneration for a period of time and then can be used for removing chromium in water again.
4. Use according to claim 3, characterized in that: in the step I, 0.5g of adsorbent is added into 1.0L of chromium-containing water, the water temperature is controlled to be 20-60 ℃, the pH value is controlled to be 1-7, and the oscillation adsorption time is 24 hours.
5. Use according to claim 3, characterized in that: the separation method of the adsorbent in the step (II) is magnetic separation or standing precipitation.
6. Use according to claim 3, characterized in that: in the third step, the concentration of NaOH is 0.1mol/L, and the regeneration time is 24 h.
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CN113134340B (en) * 2021-04-26 2023-05-16 江苏东方维德环保科技有限公司 Chromium ion adsorbent, preparation method, application and regeneration method thereof, and treatment method of chromium in leather tail water
CN113926845A (en) * 2021-09-30 2022-01-14 中山大学 Application of magnetic biochar-based iron carbide material in heavy metal contaminated soil remediation
CN114477683B (en) * 2022-01-25 2023-08-18 安徽工程大学 Pigment sludge treatment method
CN114768761A (en) * 2022-04-15 2022-07-22 广东省科学院生态环境与土壤研究所 Preparation of biochar containing high-durability free radicals and application of biochar in removing heavy metals
CN115385436B (en) * 2022-08-27 2023-12-29 西南石油大学 Method for treating sewage by uniformly loading zero-valent iron catalytic particles of core-shell graphene oxide
CN115501856A (en) * 2022-09-20 2022-12-23 燕山大学 Specific fluorine-absorbing agent and preparation method and application method thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102000552A (en) * 2010-12-06 2011-04-06 河海大学 Novel heavy metal adsorbent mainly prepared from shrimp shells and preparation method thereof
CN105771899A (en) * 2016-04-28 2016-07-20 农业部沼气科学研究所 Efficient phosphorus and heavy metal removal biochar, and preparation method and application thereof
CN110102265A (en) * 2019-04-04 2019-08-09 浙江树人学院（浙江树人大学） For the load zirconium biology compound adsorbent and regeneration method of removing fluor in water and application

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103007910B (en) * 2012-11-30 2014-06-11 燕山大学 TiO2-loaded biocomposite, preparation technology and applications
US9579635B2 (en) * 2012-12-13 2017-02-28 Basf Corporation Carbon bodies and ferromagnetic carbon bodies
CN103301809B (en) * 2013-07-01 2015-04-15 湖南大学 Magnetic carrier iron ordered mesoporous carbon, preparation method and application thereof
CN103566883A (en) * 2013-10-17 2014-02-12 复旦大学 Preparation method of hydrothermal liquefied biochar-based porous carbon and magnetic carbon material and applications of porous carbon and magnetic carbon material
CN105536700A (en) * 2015-12-22 2016-05-04 国家海洋局天津海水淡化与综合利用研究所 Method for preparing magnetic biochar from straw
CN106378105A (en) * 2016-11-21 2017-02-08 武汉理工大学 Preparation method of magnetic chitosan compound adsorbent
CN109225135A (en) * 2018-10-23 2019-01-18 山东省科学院生态研究所 A kind of modification biological charcoal adsorbent material and preparation method thereof with to Pb in water body2+Removal application
CN110357169A (en) * 2019-07-31 2019-10-22 蚌埠学院 A kind of preparation method of the magnetic mesoporous silica composite nanoparticle of yolk-eggshell structure
CN110508246A (en) * 2019-08-30 2019-11-29 华中农业大学 A kind of magnetic composite and its application based on cow dung charcoal

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102000552A (en) * 2010-12-06 2011-04-06 河海大学 Novel heavy metal adsorbent mainly prepared from shrimp shells and preparation method thereof
CN105771899A (en) * 2016-04-28 2016-07-20 农业部沼气科学研究所 Efficient phosphorus and heavy metal removal biochar, and preparation method and application thereof
CN110102265A (en) * 2019-04-04 2019-08-09 浙江树人学院（浙江树人大学） For the load zirconium biology compound adsorbent and regeneration method of removing fluor in water and application

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Highly Efficient and Rapid Lead(Ⅱ)Scavenging by the Natural Artemia Cyst Shell with Unique Three-Dimensional Porous Structure and Srong Sorption Affinity;Bo Wang et al.;《ACS Sustainable Chemistry & Engineering》;20180601;1343-1351 *

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