CN112846214A - Method for green synthesis of slow-release nano zero-valent iron by using gleditsia sinensis lam extract and application - Google Patents

Method for green synthesis of slow-release nano zero-valent iron by using gleditsia sinensis lam extract and application Download PDF

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CN112846214A
CN112846214A CN201911178390.0A CN201911178390A CN112846214A CN 112846214 A CN112846214 A CN 112846214A CN 201911178390 A CN201911178390 A CN 201911178390A CN 112846214 A CN112846214 A CN 112846214A
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slow
nano zero
valent iron
release
iron
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林爱军
武会会
杨文杰
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Beijing University of Chemical Technology
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/05—Metallic powder characterised by the size or surface area of the particles
    • B22F1/054—Nanosized particles
    • 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
    • C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
    • C02F1/62—Heavy metal compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
    • B22F2009/245—Reduction reaction in an Ionic Liquid [IL]
    • 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

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  • Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Nanotechnology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Extraction Or Liquid Replacement (AREA)

Abstract

The invention relates to a slow-release environment-repairing material, in particular to a method for green synthesis of slow-release nano zero-valent iron by utilizing a gleditsia sinensis lam extract and application thereof. The preparation method is characterized in that: 1. ultrasonic ethanol extraction method for preparing fructus Gleditsiae Abnormalis extract; 2. preparing a ferrous iron precursor solution; 3. preparing a slow-release nano zero-valent iron suspension; 4. preparing the slow-release nano zero-valent iron material. The slow-release nano zero-valent iron material prepared by the invention has good iron-release controllability while efficiently removing pollutants in water, effectively solves the problems of excessive iron source release at the early stage and insufficient iron release at the later stage, and improves the utilization rate of iron. And the preparation process of the material is simple to operate, and the used raw materials are ecological and environment-friendly, so that the material has a good application prospect.

Description

Method for green synthesis of slow-release nano zero-valent iron by using gleditsia sinensis lam extract and application
Technical Field
The invention relates to an environment-friendly repair material, in particular to a method for synthesizing slow-release nano zero-valent iron by using a gleditsia sinensis lam extract in a green manner and application thereof.
Background
The nanometer zero-valent iron has the advantages of large specific surface area, high reaction activity, strong reduction capability and the like, and is widely applied to removing pollutants such as heavy metals, inorganic anions, halogenated organic matters, antibiotics, pesticides and the like in water. At present, the synthesis of nano zero-valent iron mostly adopts a liquid phase reduction method, and strong reducing agents (such as sodium borohydride, hydrazine hydrate and the like) are generally used, and the reducing agents are generally harmful to human bodies and have high cost, so that a more ideal reducing agent is searched, and the development of a low-cost and environment-friendly stable nano zero-valent iron material is a problem which needs to be solved urgently at present.
The water gleditsia sinensis lam is an annual leguminous plant, namely camellia leaves and senna, contains high pharmacological action and rich bioactive components, is distributed in most places in China, is 10-60 cm high, and has a plurality of dispersing branches. The polyphenol substances extracted from the water honeylocust are natural antioxidants, have strong oxidation resistance and can be theoretically used as reducing agents for synthesizing the nano zero-valent iron; the natural plant components such as saccharides, colloid and the like in the extract can be coated on the surface of the zero-valent iron in the preparation process to form a natural protective layer, the protective layer can prevent the nano zero-valent iron from agglomerating due to Van der Waals force and magnetic force, simultaneously can reduce the rate of passivating the nano zero-valent iron and slow down the release of the core iron source, and plays a role of a slow release agent, so that the nano zero-valent iron is slowly released in a polluted field, the problems of excessive early-stage released iron source and insufficient later-stage released iron source are avoided, and the utilization rate of the iron is improved. And the plant components in the water saponin extract can be degraded and utilized by microorganisms in the environment as nutrient substances, so that the nutrient component proportion in the polluted environment can be adjusted, the degradation of the indigenous microorganisms to pollutants is improved, and the synergistic remediation efficiency is promoted.
The method utilizes the water gleditsia sinensis extract to synthesize the slow-release nano zero-valent iron in an environment-friendly manner, is applied to removing pollutants in the wastewater, exploits the resource utilization of the water gleditsia sinensis, reduces the preparation cost of the nano zero-valent iron, improves the utilization rate of the nano zero-valent iron, and has good application prospect.
Disclosure of Invention
The invention aims to provide a method for green synthesis of slow-release nano zero-valent iron by using a gleditsia sinensis lam extract and application thereof. The preparation method is simple, the raw materials are green and low in price, and the prepared nano zero-valent iron material has the advantages of good pollutant removal effect, strong stability, higher utilization rate and good slow release property.
The technical scheme of the invention is as follows:
a method for green synthesis of slow-release nano zero-valent iron by using a gleditsia sinensis lam extract comprises the following specific preparation steps:
step (1), preparing a gleditsia sinensis extractive solution by an ultrasonic ethanol extraction method: cleaning aerial parts of fructus Gleditsiae Abnormalis, air drying, adding 60% ethanol solution, ultrasonic extracting in 500W ultrasonic cleaner, cooling to room temperature, and vacuum ultrafiltering to obtain fructus Gleditsiae Abnormalis extractive solution;
preparing a ferrous iron precursor solution: dissolving ferric salt solid in deionized water to prepare FeSO4A solution;
preparing a slow-release nano zero-valent iron suspension: FeSO prepared in the step (2)4Adding the solution into a three-neck flask, dropwise adding the water saponin extracting solution obtained in the step (1) in the stirring process, and continuously stirring for 30min to obtain a green synthesized slow-release nano zero-valent iron suspension;
preparing a slow-release nano zero-valent iron material in the step (4): and (4) carrying out centrifugal separation on the green synthesized nano zero-valent iron suspension in the step (3), respectively washing with deionized water and ethanol, and drying the obtained precipitate in a vacuum freeze drying oven for 12 hours to obtain the green synthesized slow-release nano zero-valent iron material.
Wherein, the water honeylocust is added into the mixture in the step (1) according to the solid-liquid ratio of 1: 10, and the mixture is placed into a 500W ultrasonic cleaner for ultrasonic leaching for 20-60 min at the temperature of 30-70 ℃.
Preparing a ferric salt solution in the step (2): dissolving ferric salt solid in deionized water to prepare FeSO with concentration of 0.1mol/L4And (3) solution.
FeSO described in step (3)4The volume ratio of the solution to the water saponin extracting solution is 1: 3.
The whole process of the steps (2) and (3) is carried out in a nitrogen environment.
The invention has the advantages that:
(1) the preparation process is green: the reducing agent used in the preparation method is the gleditsia sinensis lam extract, and has the advantages of low cost, environmental protection, simple preparation process and the like.
(2) The slow release effect is as follows: according to the slow-release nano zero-valent iron prepared by the invention, the slow-release layer on the surface can slow down the release of the core iron source, so that the nano zero-valent iron is slowly released in a polluted environment, the problem that the early-stage release of the iron source is excessive and the later-stage release is insufficient is avoided, and the utilization rate of the iron is improved.
(3) The environmental applicability is strong: the method utilizes the water gleditsia sinensis extract to synthesize the slow-release nano zero-valent iron in a green way, the removal rate of hexavalent chromium under various pH conditions reaches more than 90%, and the method has strong environmental adaptability.
Drawings
FIG. 1 is a graph comparing leaching conditions of common nanometer zero-valent iron and the slow-release nanometer zero-valent iron prepared by the invention.
FIG. 2 is a comparison graph of the effect of removing Cr (VI) from water by using common nano zero-valent iron and the slow-release nano zero-valent iron prepared by the invention.
FIG. 3 shows the effect of the slow-release nanoscale zero-valent iron prepared by the method of the invention on the removal of Cr (VI) in water at different pH values.
FIG. 4 is a comparison graph of the effect of removing TNT from water by using common nano zero-valent iron and the slow-release nano zero-valent iron prepared by the invention.
Detailed Description
The following specific examples further illustrate the present invention, but are only exemplary embodiments of the present invention and are not intended to limit the present invention.
Example 1:
step (1), preparing a gleditsia sinensis extractive solution by an ultrasonic ethanol extraction method: cleaning aerial parts of fructus Gleditsiae Abnormalis, air drying, adding into 60% ethanol solution at a solid-to-liquid ratio of 1: 10, ultrasonic extracting at 40 deg.C for 50min under 500W ultrasonic wave, cooling to room temperature, and vacuum ultrafiltering to obtain fructus Gleditsiae Abnormalis extractive solution;
preparing a ferrous iron precursor solution: dissolving ferric salt solid in deionized water to prepare FeSO with the concentration of 0.1mol/L4A solution;
preparing a slow-release nano zero-valent iron suspension: under stirring, according to FeSO4Dropwise adding the water gleditsia sinensis extractive solution obtained in the step (1) into the solution and the water gleditsia sinensis extractive solution in a volume ratio of 1:3, and continuously stirring for 30min to obtain a green synthetic slow-release nano zero-valent iron suspension;
preparing a slow-release nano zero-valent iron material in the step (4): and carrying out centrifugal separation on the green synthetic nano zero-valent iron suspension, washing by using deionized water and ethanol respectively, and drying the obtained precipitate in a vacuum freeze drying oven for 12 hours to obtain the green synthetic slow-release nano zero-valent iron material.
The whole process of the steps (2) and (3) is carried out in a nitrogen environment.
Compared with the green synthesis of the slow-release nano zero-valent iron by using the common nano zero-valent iron and the gleditsia sinensis lam extract:
the common nano zero-valent iron material and the nano zero-valent iron material prepared by the invention are respectively placed in water, and the difference of material leaching solutions is observed after 48 hours, the slow-release nano zero-valent iron leaching solution prepared by the invention basically has no color change (figure 1), which shows that the slow-release nano zero-valent iron material basically overcomes the problem of poor stability of the common nano zero-valent iron in the environment.
Example 2:
the common nano zero-valent iron and the slow-release nano zero-valent iron material prepared by the invention are subjected to a Cr (VI) comparison removal experiment. Transferring 40mL of Cr (VI) solution with the initial concentration of 100mg/L into each conical flask, respectively adding 0.05g of common nano zero-valent iron and the slow-release nano zero-valent iron material prepared by the invention, placing the conical flasks into a constant-temperature oscillation box at 25 ℃ to oscillate for 6 hours at the condition of 150r/min, sampling at regular time, filtering a water sample by a 0.45-micrometer filter membrane, and measuring the concentration of Cr (VI) by adopting a dibenzoyl dihydrazide spectrophotometry method to obtain a Cr (VI) removal curve graph of different materials. As can be seen from FIG. 2, the removal rate of the slow-release nano zero-valent iron prepared by the invention to Cr (VI) is obviously higher than that of the common nano zero-valent iron, and the action duration is also obviously prolonged due to the slow-release effect.
Example 3:
40mL of Cr (VI) polluted solution with the initial concentration of 100mg/L is transferred into each conical flask, after the pH =3, 4, 5, 6, 7, 8, 9 and 10 are respectively adjusted, 0.05g of the nano zero-valent iron material prepared by the invention is added, and the nano zero-valent iron material is placed into a constant temperature shaking box at the temperature of 25 ℃ and is shaken for 6 hours under the condition of 150 r/min. After the experiment is finished, standing and precipitating to obtain supernatant, and measuring the concentration of Cr (VI) by using a diphenylcarbodihydrazide spectrophotometry method to obtain a graph (figure 3) of the removal effect of the material on the Cr (VI) under different pH values.
Therefore, the method utilizes the gleditsia sinensis lam extract to synthesize the slow-release nano zero-valent iron material in a green way, compared with the common nano zero-valent iron, the source of the raw material is wide, green and environment-friendly, the Cr (VI) in the water body can be efficiently removed, meanwhile, the method has the characteristics of long repair time and good stability, and the problem that the nano zero-valent iron is easy to passivate is effectively solved.
Example 4:
the common nano zero-valent iron and the slow-release nano zero-valent iron material prepared by the invention are subjected to a trinitrotoluene (TNT) contrast removal experiment. Transferring 40mL of TNT polluted solution with the initial concentration of 100mg/L into each conical flask, respectively adding 0.05g of common nano zero-valent iron and the slow-release nano zero-valent iron material prepared by the invention, placing the materials into a constant-temperature oscillation box at 25 ℃, oscillating for 72 hours at 150r/min, sampling at regular time, filtering a water sample by a 0.45-micrometer filter membrane, and determining the residual TNT content by adopting an ultraviolet spectrophotometry (figure 4).

Claims (5)

1. A method for green synthesis of slow-release nano zero-valent iron by using a gleditsia sinensis lam extract comprises the following steps:
step (1), preparing a gleditsia sinensis extractive solution by an ultrasonic ethanol extraction method: cleaning aerial parts of fructus Gleditsiae Abnormalis, air drying, adding 60% ethanol solution, ultrasonically heating in 500W ultrasonic wave, cooling to room temperature, and vacuum ultrafiltering to obtain fructus Gleditsiae Abnormalis extractive solution;
preparing a ferrous iron precursor solution: dissolving ferric salt solid in deionized water to prepare FeSO4A solution;
preparing a slow-release nano zero-valent iron suspension: FeSO prepared in the step (2)4Adding the solution into a three-neck flask, dropwise adding the water saponin extracting solution obtained in the step (1) in the stirring process, and continuously stirring for 30min to obtain a green synthesized slow-release nano zero-valent iron suspension;
preparing a slow-release nano zero-valent iron material in the step (4): and (4) carrying out centrifugal separation on the green synthesized nano zero-valent iron suspension in the step (3), respectively washing with deionized water and ethanol, and drying the obtained precipitate in a vacuum freeze drying oven for 12 hours to obtain the green synthesized slow-release nano zero-valent iron material.
2. The method for green synthesis of the slow-release nano zero-valent iron by utilizing the gleditsia sinensis lam extract according to claim 1, is characterized in that: adding the water saponin into the water saponin in the step (1) according to the solid-liquid ratio of 1: 10, placing the mixture into a 500W ultrasonic cleaner, and performing ultrasonic leaching for 20-60 min at the temperature of 30-70 ℃.
3. The method for green synthesis of the slow-release nano zero-valent iron by utilizing the gleditsia sinensis lam extract according to claim 1, is characterized in that: preparing a ferrous iron precursor solution: dissolving ferric salt solid in deionized water to prepare FeSO with concentration of 0.1mol/L4And (3) solution.
4. The method for green synthesis of the slow-release nano zero-valent iron by utilizing the gleditsia sinensis lam extract according to claim 1, is characterized in that: FeSO described in step (3)4The volume ratio of the solution to the water saponin extracting solution is 1: 3.
5. The method for green synthesis of the slow-release nano zero-valent iron by utilizing the gleditsia sinensis lam extract according to claim 1, is characterized in that: the whole process of the steps (2) and (3) is carried out in a nitrogen environment.
CN201911178390.0A 2019-11-27 2019-11-27 Method for green synthesis of slow-release nano zero-valent iron by using gleditsia sinensis lam extract and application Pending CN112846214A (en)

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CN107321972A (en) * 2017-06-23 2017-11-07 广州润方环保科技有限公司 A kind of store method of green syt nano zero valence iron sill
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Patent Citations (5)

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Publication number Priority date Publication date Assignee Title
WO2014209850A1 (en) * 2013-06-26 2014-12-31 Corning Incorporated Methods and apparatus for synthesis of stabilized zero valent nanoparticles
CN105251995A (en) * 2015-11-05 2016-01-20 北京化工大学 Preparation method for slow-release-type nanometer zero-valent iron particles
CN106180755A (en) * 2016-08-15 2016-12-07 华南师范大学 A kind of method utilizing Herba Eichhorniae extracting solution green syt nano zero valence iron and application
CN107321972A (en) * 2017-06-23 2017-11-07 广州润方环保科技有限公司 A kind of store method of green syt nano zero valence iron sill
CN107838433A (en) * 2017-10-17 2018-03-27 北京化工大学 A kind of crape myrtle fruit prepares the method with slow releasing function nano zero valence iron

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Application publication date: 20210528