CN112920808B - CMC-coated NZVI particles for repairing halogenated organic matters in electronic refuse landfill and preparation method thereof - Google Patents

CMC-coated NZVI particles for repairing halogenated organic matters in electronic refuse landfill and preparation method thereof Download PDF

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CN112920808B
CN112920808B CN202110183935.8A CN202110183935A CN112920808B CN 112920808 B CN112920808 B CN 112920808B CN 202110183935 A CN202110183935 A CN 202110183935A CN 112920808 B CN112920808 B CN 112920808B
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孙轶斐
田慧芳
梁莹
朱天乐
王召旭
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Beihang University
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    • C09K17/00—Soil-conditioning materials or soil-stabilising materials
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Abstract

The invention discloses a CMC-coated NZVI particle for repairing halogenated organic matters in an electronic refuse landfill and a preparation method thereof. Adding 20 g-50 g of CMC coated NZVI particles into 1000g of soil polluted by the X-POPs. The repairing temperature is 15-25 ℃, and the repairing reaction time is 24-96 h. The preparation of the CMC-coated NZVI particles is to prepare the coated nano zero-valent iron by using CMC as a high-molecular coating agent under the condition of inert atmosphere and by combining liquid-phase reduction reaction with high-temperature roasting under the atmosphere of reducing atmosphere. The CMC-coated NZVI particles are used for removing PBDEs in an electronic refuse landfill, and have the advantages of simple repair operation, high repair efficiency and low energy consumption. The crystal structure of the nano zero-valent iron is improved, the problems of agglomeration, reduction activity reduction and the like of the nano zero-valent iron in the using process are solved, secondary pollution is avoided in the repairing process, and the removal rate of PBDEs reaches more than 98%.

Description

CMC-coated NZVI particles for repairing halogenated organic matters in electronic refuse landfill and preparation method thereof
Technical Field
The invention relates to the technical field of repairing halogenated organic matters in an electronic refuse landfill, in particular to a method for repairing soil polluted by halogenated organic matters in an electronic refuse landfill by using NZVI particles coated with CMC.
Background
For the definition of soil, ISO (2005) considers the composition and occurrence of soil, considering that soil is "composed of mineral particles, organic matter, moisture, air and living organisms in the form of a stratum, which is the crust surface layer formed by the combined action of weathering and physical, chemical, and biological processes". The soil is the foundation stone of the environment and also the foundation of the life of microorganisms, plants, animals and the like; soil is a big treasury of biodiversity and antibiotics; soil is the basis for most food production in the world; soil is necessary for the production of biomass such as wood, fiber and energy crops; the soil captures carbon, which helps to slow down climate change.
Due to the increasing use of electronic devices, 80% of the electronic waste (e-waste) across the country is being recycled to asian developing countries, 90% of which are being recycled to the china guangdong. Urban electronic pollution sites are important sources of halogenated persistent organic pollutants (X-POPs), and as a typical X-POPs, polybrominated diphenyl ethers (PBDEs) containing 209 homologues are often used as flame retardants in electronic devices and the like. In some electronic waste recycling areas in China, the electronic waste contains high-content PBDEs, and the electronic waste is subjected to irregular disassembly, so that a large amount of PBDEs substances are exposed to the environment, and the soil, water and atmospheric environment pollution is caused. The national environmental protection administration sets out and formally implements the 'method for preventing and controlling the environment polluted by electronic wastes' in 2008 and 2 months, provides very clear laws, regulations and regulations for the whole process from the generation, transportation, disassembly, treatment and recovery of the electronic wastes, limits the import of the electronic wastes abroad in China, and reduces the pollution of the electronic wastes to heavy metals and brominated flame retardants brought by China. In recent years, as the interest of PBDEs has increased, research on the contamination of PBDEs has also increased. The detection research of the PBDEs concentration in domestic soil starts from 2005, and mainly focuses on areas polluted by electronic waste.
Currently, PBDEs degradation is mainly studied in sewage, sludge and sediment media, while less research is done on degradation in soil media. Biodegradation and photodegradation are the main methods for the degradation of PBDEs in soil, but PBDEs are difficult to be utilized by microorganisms due to hydrophobicity, and the degradation time is long. The photodegradation treatment cost is high, and the method is not suitable for engineering. Due to the reasons of sensitivity of detection instruments and the like, experimental support is lacked, and in-situ treatment in soil is difficult to implement, so other faster, more economic, more green and more efficient PBDEs-polluted soil remediation methods are sought.
Disclosure of Invention
On one hand, in order to realize the remediation of halogenated persistent organic pollutants (X-POPs) in soil caused by electronic refuse landfill and on the other hand improve the debromination efficiency of the soil polluted by the X-POPs, the invention designs the CMC-coated NZVI particles.
It is another object of the present invention to provide a method for preparing CMC coated NZVI particles. The preparation method is simple to operate and cheap in raw materials. The prepared CMC-coated NZVI particles have the characteristic of high reactive active sites.
The third purpose of the invention is that the CMC coated NZVI particles are applied to the soil polluted by halogenated persistent organic pollutants (X-POPs), and the debromination efficiency of the PBDEs polluted soil can be obviously improved.
The invention repairs the soil polluted by the halogenated organic matters in the electronic refuse landfill, and is characterized in that: the CMC-coated NZVI particles are added to the soil contaminated with X-POPs. Adding 20 g-50 g of CMC coated NZVI particles into 1000g of soil polluted by the X-POPs. The repairing temperature is 15-25 ℃, and the repairing reaction time is 24-96 h.
The preparation method of the CMC-coated NZVI particles for repairing halogenated organic matters in the electronic refuse landfill comprises the following steps:
step A, preparing a ferric salt mixed solution;
dissolving ferrous salt and sodium carboxymethylcellulose (CMC) in a deionized water solution under the atmosphere of inert gas nitrogen at a reaction temperature of 15-25 ℃; continuously stirring for 10-60 min under the condition of nitrogen ventilation to prepare a first reaction solution;
the dosage is as follows: the molar ratio of the iron ions of the ferrous salt to the CMC is 1: 1-10.
The nitrogen purity was 99.5% (volume content of nitrogen) and the nitrogen flow was 0.005m3/s～0.02m3/s。
The stirring speed is 60 r/s-120 r/s.
The ferrous salt is ferrous sulfate heptahydrate (FeSO)4·7H2O) or ferrous nitrate heptahydrate (Fe (NO)3)O2·7H2O)。
B, reduction reaction of iron ions;
stopping introducing air, and adding the borohydride alkaline solution into the first reaction solution at the reaction temperature of 15-25 ℃;
continuously stirring for 30-150 min under the condition of nitrogen ventilation, and standing for precipitation to prepare a second reaction solution;
the dosage is as follows: the molar ratio of iron ions of the ferrous salt to boron ions in the borohydride is 1: 2.0-3.0;
the nitrogen purity was 99.5% (volume content of nitrogen) and the nitrogen flow was 0.005m3/s～0.02m3/s。
The stirring speed is 60 r/s-120 r/s.
The borohydride alkaline solution is formed by mixing borohydride and alkaline aqueous solution, wherein the borohydride is sodium borohydride (NaBH)4) Or potassium borohydride (KBH)4). OH of borohydride alkaline solution-The concentration is 0.01 mol/L-0.02 mol/L.
Step C, centrifugally separating and taking out precipitate;
step C1, carrying out centrifugal separation on the second reaction solution for 5-30 min under the condition that the rotating speed is 2000-3500 r/min, and obtaining a precipitate;
in the present invention, the precipitate is black.
Step C2, placing the precipitate in a vacuum drying oven, and vacuumizing to 1 × 10－4Pa～1×10－2Pa, drying at 50-80 ℃ for 24-48 h to obtain dry precipitate particles;
d, calcining and sintering the CMC-coated NZVI particles at high temperature;
step D1, putting the dried precipitate particles into a corundum boat, and then putting the corundum boat into a tube furnace;
step D2, filling nitrogen and discharging air in the tube furnace;
step D3, setting the calcining temperature to be 450-550 ℃ and the calcining time to be 240-360 min;
and D4, calcining at high temperature under the condition of hydrogen atmosphere to generate the sodium carboxymethylcellulose-coated nano zero-valent iron particles, namely the CMC-coated NZVI particles.
In the invention, hydrogen is introduced as a reducing agent in the high-temperature calcination process, and the oxidized iron is highly reduced at high temperature to prepare the iron metal with higher zero-valent iron component.
Performance analysis of CMC coated NZVI particles
The CMC-coated NZVI particles prepared by the method have the single crystals with the grain size of 15 nm-50 nm and the crystal spacing of 0.22 nm-0.34 nm. The Fe metal is a monocrystal with the same arrangement rule and consistent lattice phase.
The invention has the advantages that:
(1) the preparation method of the CMC-coated NZVI particles has the advantages of simple process operation, cheap and easily-obtained raw materials, short synthesis process period, high preparation active components, small particle size and certain industrial value.
(2) The CMC-coated NZVI particles are used for repairing the soil polluted by the halogenated organic matters in the electronic refuse landfill at normal temperature, and secondary pollution is avoided in the repairing process.
(3) The CMC-coated NZVI is applied to repair the in-situ electronic refuse landfill, so that the transportation cost is reduced, the debromination of 42 PBDEs in the soil can be improved in a short time, and the practical application of the PBDEs is facilitated. Therefore, the home-made CMC coated NZVI particle in-situ electronic landfill site repair method provided by the invention has important application value. The prepared CMC-coated NZVI particles are applied to the PBDEs electronic refuse landfill site repairing process, and the debromination efficiency of the PBDEs-polluted soil can be obviously improved to more than 98%.
(4) The CMC-coated NZVI particles are directly applied to the soil polluted by halogenated persistent organic pollutants (X-POPs), and the soil can be repaired more by the characteristics of rapidness, high efficiency, in-situ repair and the like because the temperature environment is normal temperature when the soil is repaired.
Drawings
FIG. 1 is a XRD representation of the product of example 1 obtained by the process of the invention.
FIG. 2 is a TEM representation of the product of example 1 obtained by the process of the invention.
FIG. 3 is a HR-TEM characterization of the product of example 1 obtained by the process of the present invention.
FIG. 4 is an XPS characterization of the product of example 1 made by the method of the present invention.
FIG. 5 is a graph showing the degradation effect of the product of example 1 on dibromo-to nonabromo-BDEs.
FIG. 5A is a graph showing the effect of the product of example 1 on the degradation of decabromoBDEs by the process of the present invention.
FIG. 6 is a gas chromatogram of 42 PBDEs measured by GC-MS.
Detailed Description
The present invention will be further illustrated with reference to specific examples, but the present invention is not limited to the following examples.
Measuring parameters of PBDEs of X-POPs contaminated soil
Soil (polluted soil for short) of electronic waste landfill sites in the first Shanxi province of Guangdong province of China is selected for measurement.
The contaminated Soil was measured using Method 1614 branched Diphenyl Ethers in water Soil, section and Tissue by HRGC/HRMS, August 2007, pages 73-74. Measuring to obtain PBDEs (PBDEs) extracting solution, and performing qualitative and quantitative analysis on the obtained PBDEs extracting solution by GC-MS-MS (Shimadzu TQ-8040), wherein the peak time of 42 PBDEs detected by GC-MS-MS in the invention is shown in figure 6, and the total concentration of the PBDEs in the polluted soil obtained by the test is 166 ng/g. Wherein the content of the decabromodiphenyl ether (BDE-209) is the highest, and the concentration is 92.47 ng/g.
Example 1
(one) preparation of CMC-coated NZVI particles
Step A, preparing a ferric salt mixed solution;
0.03mol of ferrous nitrate heptahydrate (Fe (NO) is added at a reaction temperature of 22 DEG C3)O2·7H2O) and 0.03mol of sodium carboxymethylcellulose (CMC) are dissolved in 150mL of deionized water solution; continuously stirring for 30min under the condition of nitrogen ventilation to prepare a first reaction solution;
the nitrogen purity was 99.5% (volume content of nitrogen) and the nitrogen flow rate was 0.01m3/s。
The stirring speed is 100 r/s.
The sodium carboxymethyl cellulose (CMC) is added in the invention, and the action of the CMC is to change the agglomeration of the nano metal particles, which is beneficial to improving the contact area of the metal particles and reactants, thereby improving the reaction activity of the CMC.
B, reduction reaction of iron ions;
stopping the aeration, reacting at 22 ℃ and adding 0.072mol of potassium borohydride (KBH)4) Adding the mixture into the first reaction solution;
continuously stirring for 50min under the condition of nitrogen ventilation, standing and precipitating to prepare a second reaction solution;
the nitrogen purity was 99.5% (volume content of nitrogen) and the nitrogen flow rate was 0.01m3/s。
The stirring speed is 100 r/s.
Step C, centrifugally separating and taking out precipitate;
step C1, carrying out centrifugal separation on the second reaction solution for 30min under the condition that the rotating speed is 3000r/min to obtain black precipitates;
step C2, placing the black precipitate in a vacuum drying oven, and vacuumizing to 1 × 10－2Pa, drying at 50 ℃ for 48 hours to obtain dry precipitate particles;
d, calcining and sintering the CMC-coated NZVI particles at high temperature;
step D1, putting the dried precipitate particles into a corundum boat, and then putting the corundum boat into a tube furnace;
step D2, filling nitrogen and discharging air in the tube furnace;
step D3, setting the calcining temperature at 500 ℃ and the calcining time at 300 min;
and (3) under the condition of hydrogen atmosphere, calcining at high temperature until the calcination is finished, cooling, and taking out to generate the highly-reduced sodium carboxymethylcellulose-coated nano zero-valent iron particles, namely the CMC-coated NZVI particles.
In the invention, the prepared particles are calcined at high temperature in a reducing atmosphere, which is beneficial to reducing the metal oxidation rate and improving the reduction performance of metal.
Performance analysis of CMC coated NZVI particles
X-ray of the CMC-coated NZVI particles prepared in example 1Line diffraction characterization (XRD), shown in FIG. 1, zero valent iron (Fe) in 2 θ at 44.7 ° (PDF- #06-0696) and 65.7 ° (PDF-PDF #65-4899)0) 34.671 ° (PDF- #88-2357), iron oxide peaks occurred, the presence of iron oxide being due to Fe during the test0Due to surface oxidation, Fe0The oxide film of the oxide on the surface forms a protective layer which helps to prevent Fe0Thereby maintaining Fe0Activity of (2).
The CMC coated NZVI particles prepared in example 1 were analyzed by Transmission Electron Microscopy (TEM) and high resolution transmission electron microscopy (HR-TEM). The CMC-coated NZVI particulate matter is shown in a figure 2, wherein the macroscopic morphology characteristics (15-50 nm) of the CMC-coated NZVI particulate matter are in a spherical shape with different sizes, the figure 3 is a high-resolution image of Fe metal, the Fe crystal spacing is 0.2nm, the Fe metal is single crystals with the same arrangement rule and the same crystal lattice phase.
The CMC-coated NZVI particles prepared in example 1 were subjected to X-ray photoelectron spectroscopy (XPS) analysis, and as shown in fig. 4, the prepared material consisted mainly of Fe, O and C elements, and by analyzing the Fe element, Fe existed mainly in the form of zero-valent iron and iron oxide.
(II) remediation of PBDEs-containing soils
1000g of soil polluted by X-POPs is added with 30g of CMC coated NZVI particles, the repairing temperature is 22 ℃, and the repairing reaction time is 96 hours.
The selected CMC-coated NZVI has low manufacturing cost and simple operation, not only saves the cost, but also can not cause secondary pollution to the soil by the metal ions generated by adding the CMC-coated NZVI into the soil, and can realize the safe utilization of the soil.
(III) Performance testing after remediation of contaminated soil
Referring to fig. 5 and 5A, after the CMC coated NZVI in example 1 is analyzed by GC-MS, 42 PBDEs in soil are repaired at the same time, and after the reaction, the debromination efficiency of the soil polluted by 1-10 bromo-BDEs can reach more than 98%. Di-in the figure represents dibromo, and Tri-represents tribromo; tetra-represents tetrabromo; peta-represents pentabromo; hexa-represents hexabromo; hepta-represents heptabromo; octabromo-represents; nona-represents nonabromo; deca-represents decabromo.
The CMC coats the NZVI to degrade Di-Nona-BDEs and reacts for 0-48 h, the debromination rate of the high-brominated BDEs of the soil sample is high, and the debromination rate of the total PBDEs reaches more than 98%; the Br content of BDEs with bromization shows a descending trend along with the reaction time, and the debromination effect of the CMC coated NZVI is as follows: high bromination → low bromination; low bromination and simultaneous debromination.
Example 2
(one) preparation of CMC-coated NZVI particles
Step A, preparing a ferric salt mixed solution;
0.04mol of ferrous sulfate heptahydrate (FeSO) is added at a reaction temperature of 22 DEG C4·7H2O) and 0.1mol of sodium carboxymethylcellulose (CMC) are dissolved in 150mL of deionized water solution; continuously stirring for 30min under the condition of nitrogen ventilation to prepare a first reaction solution;
the nitrogen purity was 99.5% (volume content of nitrogen) and the nitrogen flow rate was 0.015m3/s。
The stirring speed is 100 r/s.
The sodium carboxymethyl cellulose (CMC) is added in the invention, and the action of the CMC is to change the agglomeration of the nano metal particles, which is beneficial to improving the contact area of the metal particles and reactants, thereby improving the reaction activity of the CMC.
B, reduction reaction of iron ions;
the aeration is stopped, and 0.08mol of sodium borohydride (NaBH) is added at the reaction temperature of 22 DEG C4) Adding the mixture into the first reaction solution;
continuously stirring for 70min under the condition of nitrogen ventilation, standing and precipitating to prepare a second reaction solution;
the nitrogen purity was 99.5% (volume content of nitrogen) and the nitrogen flow rate was 0.015m3/s。
The stirring speed is 100 r/s.
Step C, centrifugally separating and taking out precipitate;
step C1, performing centrifugal separation on the second reaction solution for 25min at the rotating speed of 3200r/min to obtain black precipitate;
step C2, placing the black precipitate in a vacuum drying oven, and vacuumizing to 1 × 10－3Pa, drying at 60 ℃ for 36h to obtain dry precipitate particles;
d, calcining and sintering the CMC-coated NZVI particles at high temperature;
step D1, putting the dried precipitate particles into a corundum boat, and then putting the corundum boat into a tube furnace;
step D2, filling nitrogen and discharging air in the tube furnace;
step D3, setting the calcining temperature at 500 ℃ and the calcining time at 330 min;
and (3) under the condition of hydrogen atmosphere, calcining at high temperature until the calcination is finished, cooling, and taking out to generate the highly-reduced sodium carboxymethylcellulose-coated nano zero-valent iron particles, namely the CMC-coated NZVI particles.
In the invention, the prepared particles are calcined at high temperature in a reducing atmosphere, which is beneficial to reducing the metal oxidation rate and improving the reduction performance of metal.
Performance analysis of CMC coated NZVI particles
X-ray diffraction characterization (XRD) of the CMC-coated NZVI particles prepared in example 2 revealed the appearance of zero-valent iron (Fe) in 2 theta at 44.7 ° (PDF- #06-0696) and 65.7 ° (PDF-PDF #65-4899)0) 34.671 ° (PDF- #88-2357), iron oxide peaks occurred, the presence of iron oxide being due to Fe during the test0Due to surface oxidation, Fe0The oxide film of the oxide on the surface forms a protective layer which helps to prevent Fe0Thereby maintaining Fe0Activity of (2).
The CMC coated NZVI particles prepared in example 2 were analyzed by Transmission Electron Microscopy (TEM) and high resolution transmission electron microscopy (HR-TEM). The CMC-coated NZVI particulate matter has macroscopic morphology characteristics (15-50 nm) and presents spherical shapes with different sizes, the high resolution image of Fe metal is obtained, the Fe crystal spacing is 0.25nm, and the Fe metal is a single crystal with the same arrangement rule and the same crystal lattice phase.
The CMC-coated NZVI particles prepared in example 2 were subjected to X-ray photoelectron spectroscopy (XPS) analysis, and the prepared material consisted mainly of Fe, O and C elements, and by analyzing the Fe element, Fe was mainly present in the form of zero-valent iron and further contained a small amount of iron oxide.
(II) remediation of PBDEs-containing soils
Adding 50g of CMC coated NZVI particles into 1000g of soil polluted by X-POPs, wherein the repairing temperature is 20 ℃, and the repairing reaction time is 72 hours.
The selected CMC-coated NZVI has low manufacturing cost and simple operation, not only saves the cost, but also can not cause secondary pollution to the soil by the metal ions generated by adding the CMC-coated NZVI into the soil, and can realize the safe utilization of the soil.
(III) Performance testing after remediation of contaminated soil
The GC-MS-MS is used for analysis, the CMC coated NZVI in the embodiment 2 simultaneously repairs 42 PBDEs in the soil, and after reaction, the debromination efficiency of the soil polluted by 1-10 bromo BDEs can reach more than 95%.
The CMC coats the NZVI to degrade Di-Nona-BDEs and reacts for 0-48 h, the debromination rate of the high-brominated BDEs of the soil sample is high, and the debromination rate of the total PBDEs reaches more than 95%; the Br content of BDEs with bromization shows a descending trend along with the reaction time, and the debromination effect of the CMC coated NZVI is as follows: high bromination → low bromination; low bromination and simultaneous debromination.

Claims (1)

1. A method for repairing soil polluted by halogenated organic matters in an electronic refuse landfill is characterized by comprising the following steps: adding CMC coated NZVI particles into the soil polluted by X-POPs; adding 20 g-50 g of CMC coated NZVI particles into 1000g of soil polluted by X-POPs; the repairing temperature is 15-25 ℃, and the repairing reaction time is 24-96 h; the pollution of the X-POPs is 42 kinds of 1-10 brominated polybrominated diphenyl ethers;
the preparation steps of the CMC-coated NZVI particles are as follows:
step A, preparing a ferric salt mixed solution;
dissolving ferrous salt and sodium carboxymethylcellulose in deionized water solution under the atmosphere of inert gas nitrogen at the reaction temperature of 15-25 ℃; continuously stirring for 10-60 min under the condition of nitrogen ventilation to prepare a first reaction solution; the dosage is as follows: the molar ratio of iron ions of the ferrous salt to the sodium carboxymethyl cellulose is 1: 1-10; the nitrogen purity was 99.5% by volume, and the nitrogen flow was 0.005m3/s～0.02m3S; the stirring speed is 60 r/s-120 r/s; the ferrous salt is ferrous sulfate heptahydrate or ferrous nitrate heptahydrate;
b, reduction reaction of iron ions;
stopping introducing air, and adding the borohydride alkaline solution into the first reaction solution at the reaction temperature of 15-25 ℃; continuously stirring for 30-150 min under the condition of nitrogen ventilation, and standing for precipitation to prepare a second reaction solution; the dosage is as follows: the molar ratio of iron ions of the ferrous salt to boron ions in the borohydride is 1: 2.0-3.0; the nitrogen purity was 99.5% by volume, and the nitrogen flow was 0.005m3/s～0.02m3S; the stirring speed is 60 r/s-120 r/s; the borohydride alkaline solution is formed by mixing borohydride and an alkaline aqueous solution, wherein the borohydride is sodium borohydride or potassium borohydride; OH of borohydride alkaline solution-The concentration is 0.01 mol/L-0.02 mol/L;
step C, centrifugally separating and taking out precipitate;
step C1, carrying out centrifugal separation on the second reaction solution for 5-30 min under the condition that the rotating speed is 2000-3500 r/min, and obtaining a precipitate; the precipitate was black;
step C2, placing the precipitate in a vacuum drying oven, and vacuumizing to 1 × 10－4Pa～1×10－2Pa, drying at 50-80 ℃ for 24-48 h to obtain dry precipitate particles;
d, calcining and sintering the CMC-coated NZVI particles at high temperature;
step D1, putting the dried precipitate particles into a corundum boat, and then putting the corundum boat into a tube furnace;
step D2, filling nitrogen and discharging air in the tube furnace;
step D3, setting the calcining temperature to be 450-550 ℃ and the calcining time to be 240-360 min;
d4, calcining at high temperature under the condition of hydrogen atmosphere to generate sodium carboxymethylcellulose-coated nano zero-valent iron particles, namely CMC-coated NZVI particles;
the grain size of the prepared CMC-coated NZVI particles is 15 nm-50 nm, the grain spacing is 0.22 nm-0.34 nm, and the Fe metal is a single crystal with the same arrangement rule and consistent lattice phase.
CN202110183935.8A 2020-02-20 2021-02-10 CMC-coated NZVI particles for repairing halogenated organic matters in electronic refuse landfill and preparation method thereof Active CN112920808B (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102179524A (en) * 2011-04-18 2011-09-14 景德镇陶瓷学院 Method for preparing coated nano zero valent iron by rheological phase reaction method, and prepared product thereof
CN102701297A (en) * 2012-05-29 2012-10-03 华南师范大学 Mesoporous silicon dioxide microsphere-loaded zero-valent iron nanoparticle (SiO2@ FeOOH@ Fe) and preparation method and application thereof
CN106984640A (en) * 2017-05-08 2017-07-28 湖南大学 The method of nano zero valence iron restoration of soil polluted by heavy metal

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102179524A (en) * 2011-04-18 2011-09-14 景德镇陶瓷学院 Method for preparing coated nano zero valent iron by rheological phase reaction method, and prepared product thereof
CN102701297A (en) * 2012-05-29 2012-10-03 华南师范大学 Mesoporous silicon dioxide microsphere-loaded zero-valent iron nanoparticle (SiO2@ FeOOH@ Fe) and preparation method and application thereof
CN106984640A (en) * 2017-05-08 2017-07-28 湖南大学 The method of nano zero valence iron restoration of soil polluted by heavy metal

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