CN104310566A - Organic wastewater treatment method based on polyaniline coated nanometer zero-valent iron - Google Patents
Organic wastewater treatment method based on polyaniline coated nanometer zero-valent iron Download PDFInfo
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- CN104310566A CN104310566A CN201410604044.5A CN201410604044A CN104310566A CN 104310566 A CN104310566 A CN 104310566A CN 201410604044 A CN201410604044 A CN 201410604044A CN 104310566 A CN104310566 A CN 104310566A
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- polyaniline
- waste water
- nano zero
- valence iron
- zero valence
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Abstract
The invention discloses an organic wastewater treatment method based on polyaniline coated nanometer zero-valent iron. The organic wastewater treatment method comprises the following steps: taking the polyaniline coated nanometer zero-valent iron as a catalyst, taking air or oxygen as an oxidizing agent, meanwhile adding a redox mediator, activating oxygen to form active oxygen in situ, and degrading organic pollutants in the water. The polyaniline coated nanometer zero-valent iron is high in catalytic activity, capable of directly utilizing oxygen in air, low in cost, environment-friendly, easy to recycle, and capable of being recycled; the method is simple in equipment, convenient to operate, and capable of efficiently degrading the organic pollutants in the water within a wider pH value range, and has a bright application prospect.
Description
Technical field
The invention belongs to field of waste water treatment, be specifically related to a kind of method based on polyaniline-coated type nano zero valence iron process organic waste water.
Background technology
In recent years, based on Zero-valent Iron/O
2the high-level oxidation technology of oxidation system receives extensive concern both domestic and external, and this technology effectively can process Some Organic Pollutants in water (as halohydrocarbon, agricultural chemicals and dyestuff etc.).In this system, it is that Zero-valent Iron is by bielectron bang path and O that the Forming Mechanism of active oxygen mainly contains two kinds: one
2reaction produces H
2o
2; Two is Fe that Zero-valent Iron oxidation generates
2+by single electron bang path and O
2reaction produces H
2o
2.Then, the Fe of generation
2+and H
2o
2by Fenton reaction generate hydroxyl radical free radical (
.oH).Zero-valent Iron catalytic activation molecular oxygen is a complicated heterogeneous reaction process, is subject to the impact of the factors such as pH, dissolved oxygen concentration, Zero-valent Iron specific surface area and consumption, coexisting substances and temperature of reaction.
Utilize ZVI/O
2the process of system activate molecular oxygen is difficult to biodegradable organic waste water, is a kind of ideal technology.Because reaction conditions is gentle, product is nontoxic, just can realize the feature of degrading at normal temperatures and pressures, makes it compare conventional treatment process and present obvious superiority in process pollutent.But due to the physico-chemical property that nano zero valence iron is special, make it there is following problem in actual applications: (1), because nano zero valence iron granularity is little, specific surface area is large, surface energy is large and self exists magnetic, is thus easy to reunite; (2) very easily oxidized in atmosphere, form passivation layer and reduce activity; (3) because nano material has certain bio-toxicity, in actual applications, nano zero valence iron difficulty reclaims, and can form potential secondary pollution.In order to address these problems, increasing nano zero valence iron modification technology arises at the historic moment.By modifying nano particle, effectively can suppress to reunite, increasing specific surface area, reduce the negative impact that the ecosystem is caused.
Carrying out Surface coating to nano zero valence iron is a kind of effective anti-oxidation method, and can effectively prevent particle growth and reunion.By carrying out suitable Surface coating process to Zero-valent Iron, the dispersiveness of particle and the surfactivity of particle can be improved, making particle surface obtain new physics, chemistry, mechanical property and new function; Also can improve the consistency between particle and other materials.
Polyaniline is a kind of high molecular synthetic material, be commonly called as conductive plastics, it is a class special type function material, has the density of plastics, there is again the electroconductibility of metal and the workability of plastics, all serve many purposes in electronic industry, information engineering, defence engineering etc.Polyaniline is also a kind of Surface coating material of good performance, not only can solve the problem of the oxidizable and easy reunion of nano zero valence iron, and play its conductivity, be conducive to ZVI/O for clad nano Zero-valent Iron
2transfer transport in system, promotes the formation of active oxygen.
Redox mediators is as electron transit mediator, and the circulation conversion by its oxidation state and reduction-state accelerates electronics by the transmission of primary electron donor to final electron acceptor(EA), thus makes speed of reaction improve one to several order of magnitude.Natural organic matter, polyoxometallate, gac and quinones substance etc. all as redox mediators, can be successfully applied to oxidative degradation organic pollutants.Wherein quinones substance has the advantages such as electron transfer rate is fast, good reversibility, effectively improves the oxidation efficiency of reaction.
The present invention is using polyaniline-coated type nano zero valence iron as catalyzer, and activate molecular oxygen original position forms H
2o
2, in this system, add redox mediators simultaneously, build stable, efficient organic waste water oxidative degradation system.
Summary of the invention
The object of the invention is to solve the deficiencies in the prior art, a kind of method based on polyaniline-coated type nano zero valence iron process organic waste water is provided.Method of the present invention has the advantages such as equipment is simple, easy to operate, with low cost, non-selectivity, applicable pH value a wider range (pH is 3.0 ~ 11.0).
Technical scheme of the present invention is: a kind of method based on polyaniline-coated type nano zero valence iron process organic waste water, it is characterized in that: in organic waste water, add a certain amount of polyaniline-coated type nano zero valence iron as catalyzer, simultaneously, add a certain amount of redox mediators, and pass into air or oxygen, by activate molecular oxygen under room temperature, original position produces H
2o
2, with the Fe generated
2+form Fenton reaction, the organic pollutant in water is degraded.
The pH value of described organic waste water is 3.0 ~ 11.0.
Described organic waste water Middle molecule oxygen concn is 2.0 ~ 8.0mg/L.
Described redox mediators comprises anthraquinone-2-sodium, anthraquinone-1-sulfonic acid sodium, anthraquinone-2,6-disulfonic acid, riboflavin, cobalami, bromamine acid, Resorcinol, poly-Resorcinol, humic acid, 1-aminoanthraquinone and 2-aminoanthraquinone etc., in reaction system, the concentration of redox mediators is 10 ~ 200mg/L.
When described organic waste water concentration is 1.0 ~ 30.0mg/L, it is 0.5 ~ 10.0g/L that polyaniline-coated type nano zero valence iron optimizes consumption.
Described polyaniline-coated type nano zero valence iron is spherical, and its preparation method is: prepared by (1) Zero-valent Iron.At room temperature, by a certain amount of FeSO
47H
2o adds (volume ratio) in ethanol and deionized water, and ultrasonic 10min makes it be scattered in solution.In proportion by the sodium borohydride of 2.5mol/L or solution of potassium borohydride (mol ratio of sodium borohydride or POTASSIUM BOROHYDRIDE and iron ion is 3:1) with 2 speed instillations per second wherein, magnetic agitation 30min, make its complete reaction, carry out Magneto separate, and use washing with alcohol product, vacuum-drying 12h at 60 DEG C; (2) polyaniline preparation.At room temperature, a certain amount of distilled aniline and p-methyl benzenesulfonic acid are dissolved in deionized water, in ice-water bath, drip ammonium persulfate solution under magnetic agitation subsequently, drip and terminate rear continuation stirring 6h, use acetone suction filtration, washing subsequently, vacuum-drying 12h at 60 DEG C; (3) polyaniline/Zero-valent Iron preparation.A certain proportion of Zero-valent Iron and polyaniline are dissolved in DMF, stir, vacuum-drying at 60 DEG C.
In described polyaniline-coated type nano zero valence iron, the mass ratio of polyaniline and nano zero valence iron is 1:(5 ~ 20).
Usefulness of the present invention is mainly reflected in:
(1) at the composite catalyst that Zero-valent Iron Surface coating polyaniline is formed, both there is higher catalytic activity, overcome again the agglomeration of Zero-valent Iron thus the utilization ratio of raising Zero-valent Iron;
(2) polyaniline is a kind of high molecular synthetic material, has very strong adsorptive power, by Adsorption of Organic to surface, can improve speed of reaction, reduce the reaction times; And the stability of nano zero valence iron is too increased with polyaniline-coated Zero-valent Iron;
(3) polyaniline is a kind of conductive polymers, is conducive to Zero-valent Iron and O
2transfer transport between molecule, the formation of active oxygen in Promotion system, meanwhile, adding of redox mediators, also effectively promotes the transfer of electronics.
(4) utilize molecular oxygen as oxygenant, without the need to additional hydrogen peroxide, there is with low cost, the advantage such as environmental friendliness, wide material sources;
(5) reaction conditions is gentle, the organic pollutant within the scope of wider pH efficiently, fast in degradation water, non-secondary pollution;
(6) catalyst preparation process is simple, and cost is low, and catalyzer has magnetic, is easy to reclaim, and can reuse, environmental friendliness, have a good application prospect.
Accompanying drawing explanation
The x-ray diffraction pattern (XRD) of polyaniline-coated type nano zero valence iron in Fig. 1 embodiment of the present invention 1
The infrared spectrogram (FTIR) (wherein a is polyaniline-coated type nano zero valence iron, and b is polyaniline) of polyaniline-coated type nano zero valence iron in Fig. 2 embodiment of the present invention 1
In Fig. 3 embodiment of the present invention 1, polyaniline-coated type nano zero valence iron recycles the design sketch of rhodamine B degradation.
Embodiment
Below in conjunction with embodiment, the specific embodiment of the present invention is further explained, but the scope of protection of present invention is not limited in this.
embodiment 1
Compound concentration is the rhdamine B waste water 10mL of 2.5mg/L, and with HCl or NaOH adjust ph for 3.3, and pass into air, water Middle molecule oxygen concn is made to be 3.0mg/L, add 20.0mg polyaniline-coated type nano zero valence iron (mass ratio of polyaniline and nano zero valence iron is 1:10) and 1.0mg anthraquinone-2-sulfonic acid sodium salt, room temperature lower magnetic force stirs.After 120min, rhodamine B degradation rate is 88.5%.
Under same experimental conditions, add 18.0mg nano zero valence iron and 1.0mg anthraquinone-2-sulfonic acid sodium salt in 10mL rhdamine B waste water, after reaction 120min, rhodamine B degradation rate is 39.2%.
embodiment 2
Compound concentration is the rhdamine B waste water 10mL of 30.0mg/L, and with HCl or NaOH adjust ph for 6.5, and pass into oxygen, water Middle molecule oxygen concn is made to be 8.0mg/L, add 20.0mg polyaniline-coated type nano zero valence iron (mass ratio of polyaniline and nano zero valence iron is 1:10) and 1.0mg cobalami, room temperature lower magnetic force stirs.After 120min, rhodamine B degradation rate is 72.4%.
Under same experimental conditions, add 18.0mg nano zero valence iron and 1.0mg cobalami in 10mL rhdamine B waste water, after reaction 120min, rhodamine B degradation rate is 31.7%.
embodiment 3
Compound concentration is the 2-chlordiphenyl waste water 10mL of 1.0mg/L, and with HCl or NaOH adjust ph for 3.0, and pass into air, water Middle molecule oxygen concn is made to be 2.0mg/L, add 100.0mg polyaniline-coated type nano zero valence iron (mass ratio of polyaniline and nano zero valence iron is 1:5) and 0.1mg anthraquinone-2-sulfonic acid sodium salt, room temperature lower magnetic force stirs.After 120min, 2-chlordiphenyl degradation rate is 70.8%.
Under same experimental conditions, in 10mL 2-chlordiphenyl waste water, add 80.0mg nano zero valence iron and 0.1mg anthraquinone-2-sulfonic acid sodium salt, after reaction 120min, 2-chlordiphenyl degradation rate is 33.5%.
embodiment 4
Compound concentration is 2 of 2.0mg/L, 4-Dichlorophenol waste water 10mL, and with HCl or NaOH adjust ph for 11.0, and pass into air, water Middle molecule oxygen concn is made to be 3.0mg/L, add 5.0mg polyaniline-coated type nano zero valence iron (mass ratio of polyaniline and nano zero valence iron is 1:20) and 2.0mg anthraquinone-2-sulfonic acid sodium salt, room temperature lower magnetic force stirs.After 120min, 2,4-Dichlorophenol degradation rate is 55.7%.
Under same experimental conditions, in 10mL 2,4-Dichlorophenol waste water, add 4.8mg nano zero valence iron and 2.0mg anthraquinone-2-sulfonic acid sodium salt, after reaction 120min, 2,4-Dichlorophenol degradation rates are 26.1%.
embodiment 5
Compound concentration is the nitrobenzene waste water 10mL of 5.0mg/L, and with HCl or NaOH adjust ph for 4.2, and pass into air, water Middle molecule oxygen concn is made to be 3.0mg/L, add 30.0mg polyaniline-coated type nano zero valence iron (mass ratio of polyaniline and nano zero valence iron is 1:10) and 1.0mg Resorcinol, room temperature lower magnetic force stirs.After 120min, nitrobenzene degradation rate is 86.2%.
Under same experimental conditions, add 27.0mg nano zero valence iron and 1.0mg Resorcinol in 10mL nitrobenzene waste water, after reaction 120min, nitrobenzene degradation rate is 36.9%.
Claims (5)
1. the method based on polyaniline-coated type nano zero valence iron process organic waste water, it is characterized in that: in organic waste water, add a certain amount of polyaniline-coated type nano zero valence iron as catalyzer, simultaneously, add a certain amount of redox mediators, and pass into air or oxygen, by activate molecular oxygen under room temperature, original position produces H
2o
2, with the Fe generated
2+form Fenton reaction, the organic pollutant in water is degraded.
2. a kind of method based on polyaniline-coated type nano zero valence iron process organic waste water according to claim 1, is characterized in that: in described polyaniline-coated type nano zero valence iron, polyaniline and nanometer zero mass are than being 1:(5 ~ 20).
3. a kind of method based on polyaniline-coated type nano zero valence iron process organic waste water according to claim 1, it is characterized in that: when described organic waste water concentration is 1.0 ~ 30.0mg/L, it is 0.5 ~ 10.0g/L that polyaniline-coated type nano zero valence iron optimizes consumption.
4. a kind of method based on polyaniline-coated type nano zero valence iron process organic waste water according to claim 1, it is characterized in that: described redox mediators comprises anthraquinone-2-sodium, anthraquinone-1-sulfonic acid sodium, anthraquinone-2,6-disulfonic acid, riboflavin, cobalami, bromamine acid, Resorcinol, poly-Resorcinol, humic acid, 1-aminoanthraquinone and 2-aminoanthraquinone etc., in reaction system, the concentration of redox mediators is 10 ~ 200mg/L.
5. a kind of method based on polyaniline-coated type nano zero valence iron process organic waste water according to claim 1, is characterized in that: described organic waste water Middle molecule oxygen concn is 2.0 ~ 8.0mg/L.
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Cited By (8)
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| CN104944564A (en) * | 2015-06-19 | 2015-09-30 | 四川师范大学 | Method for preparing reducing agent for removing nitrate in water |
| CN105502627A (en) * | 2015-12-07 | 2016-04-20 | 西安建筑科技大学 | Method for degrading printing and dyeing wastewater by anthraquinone matter |
| CN106565010A (en) * | 2016-10-18 | 2017-04-19 | 哈尔滨工业大学 | Method for treating organic pollutants in water |
| CN106854021A (en) * | 2015-12-08 | 2017-06-16 | 天津工业大学 | A kind of humic acid strengthens the new method of reduction pretreatment industrial wastewater |
| CN110668545A (en) * | 2019-10-17 | 2020-01-10 | 江苏环保产业技术研究院股份公司 | Water treatment agent based on nano system and preparation method thereof |
| CN111320986A (en) * | 2020-03-27 | 2020-06-23 | 浙江易承环境科研有限公司 | Soil remediation technology |
| CN112408527A (en) * | 2020-10-21 | 2021-02-26 | 西安交通大学 | Method for heating and cooling monatomic fluid to cooperatively treat wastewater |
| CN114146709A (en) * | 2021-12-17 | 2022-03-08 | 南京大学 | Iron/polydopamine/carbon composite catalyst with reduction and oxidation dual performance and preparation method and application thereof |
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Cited By (11)
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| CN104944564A (en) * | 2015-06-19 | 2015-09-30 | 四川师范大学 | Method for preparing reducing agent for removing nitrate in water |
| CN105502627A (en) * | 2015-12-07 | 2016-04-20 | 西安建筑科技大学 | Method for degrading printing and dyeing wastewater by anthraquinone matter |
| CN105502627B (en) * | 2015-12-07 | 2018-01-12 | 西安建筑科技大学 | A kind of method of anthraquinones degraded dyeing waste water |
| CN106854021A (en) * | 2015-12-08 | 2017-06-16 | 天津工业大学 | A kind of humic acid strengthens the new method of reduction pretreatment industrial wastewater |
| CN106565010A (en) * | 2016-10-18 | 2017-04-19 | 哈尔滨工业大学 | Method for treating organic pollutants in water |
| CN110668545A (en) * | 2019-10-17 | 2020-01-10 | 江苏环保产业技术研究院股份公司 | Water treatment agent based on nano system and preparation method thereof |
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| CN111320986B (en) * | 2020-03-27 | 2021-11-09 | 浙江易承环境科研有限公司 | Soil remediation technology |
| CN112408527A (en) * | 2020-10-21 | 2021-02-26 | 西安交通大学 | Method for heating and cooling monatomic fluid to cooperatively treat wastewater |
| CN112408527B (en) * | 2020-10-21 | 2021-09-07 | 西安交通大学 | Method for heating and cooling monatomic fluid to cooperatively treat wastewater |
| CN114146709A (en) * | 2021-12-17 | 2022-03-08 | 南京大学 | Iron/polydopamine/carbon composite catalyst with reduction and oxidation dual performance and preparation method and application thereof |
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