CN107651743A - A kind of nano-magnetic flocculant for magnetic separation technique and preparation method thereof - Google Patents
A kind of nano-magnetic flocculant for magnetic separation technique and preparation method thereof Download PDFInfo
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- CN107651743A CN107651743A CN201711071772.4A CN201711071772A CN107651743A CN 107651743 A CN107651743 A CN 107651743A CN 201711071772 A CN201711071772 A CN 201711071772A CN 107651743 A CN107651743 A CN 107651743A
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- magnetic
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- nanometer
- polyacrylamide
- flocculant
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Classifications
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- 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
- C02F1/54—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
- C02F1/56—Macromolecular compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/48—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
Abstract
The invention discloses a kind of nano-magnetic flocculant for magnetic separation technique and preparation method thereof, the nano-magnetic flocculant is by nanometer Fe3O4, polyacrylamide and PDDA composition, the polyacrylamide and PDDA are in nanometer Fe3O4Surface forms one layer of organic protective film.The nano-magnetic flocculant passes through FeSO4 Prepare Fe（OH）2 Colloid, and pass through Oxidation of Fe（OH）2Colloid obtains epigranular, the nanometer Fe of good dispersion3O4Particle, and the organic functions film formed by polyacrylamide and PDDA is coated, and is made its epigranular, is not easy to reunite, flocculating effect is more preferable.The present invention is using polyacrylamide and PDDA in nanometer Fe3O4Particle surface forms one layer of organic protective film, reaches scattered nanometer Fe3O4Particle, prevent nanometer Fe3O4Particle is oxidized to α Fe2O3Cause magnetic to weaken, make magnetic kind lose can magnetic recovery characteristic.
Description
Technical field
The present invention relates to technical field of heavy metal wastewater treatment, and in particular to a kind of nano-magnetic for magnetic separation technique
Flocculant and preparation method thereof.
Background technology
Magnetic separation technique is a kind of technology that material is carried out to magnetic field processing, and the application of the technology has penetrated into each neck
Domain.Magneto separate is separated using the magnetic of impurity particle in waste water, for non magnetic or weak magnetic particle in water, utilizes magnetic
Property inoculation technique can make them have magnetic.By the effect in external force magnetic field, magnetic suspended solid in waste water is isolated
Come, so as to reach the purpose of purified water.
The technical finesse waste water speed is fast, disposal ability is big, and is not influenceed by natural temperature, difficult to other separation methods
There is very strong separating capacity with the waste water of the superfine suspension and low concentration of removing.The particularly mistake of High-gradient Magnetic filter separator
Filtering velocity degree is 10~30 times of the high-rate fitration machine of general processing, equivalent to 100 times of sedimentation basin.Magnetic separating apparatus volume
It is small, simple in construction, safeguard easily, expense is low, occupations of land is few, can greatly shorten the construction period, and those removable drug resistances with
The very strong pathogenic microorganism of toxicity, bacterium and the organic matter of some difficult degradations, compared with being sterilized with chlorine or chlorinated product, Magneto separate
The organic matter that technology will not produce waste water and be produces haloform (THMs) and other halogenated hydrocarbon compounds with chlorine reaction, these changes
Compound is the virulence factor of a variety of diseases.
At present, the conventional nano-magnetic flocculant of magnetic separation technique uses Fe mostly3O4As magnetic kind, its cost is relatively low, magnetic
Better performances.But use nanometer Fe3O4During as magnetic kind, the α-Fe of generating portion weak magnetic are usually oxidized easily2O3, cause magnetic
Property substantially reduces, make magnetic kind lose can magnetic recovery characteristic.
The content of the invention
The present invention is directed to prior art, there is provided one kind is with nanometer Fe3O4As the nano-magnetic flocculant of magnetic kind, for magnetic
In isolation technics, and in nanometer Fe3O4Particle surface forms one layer of organic protective film, makes nanometer Fe3O4Particle is not easy to be oxidized,
Make nanometer Fe3O4Particle has by the characteristic of magnetic recovery.
The present invention also provides a kind of preparation method of the nano-magnetic flocculant for magnetic separation technique, using FeSO4It is molten
Liquid precipitate is into Fe (OH)2Colloid is reoxidized as nanometer Fe3O4Particle, its nanometer Fe prepared3O4Grain graininess is small, size distribution is equal
It is even.
A kind of nano-magnetic flocculant for magnetic separation technique provided by the invention, by nanometer Fe3O4, polyacrylamide
Formed with PDDA.The polyacrylamide and PDDA are in nanometer
Fe3O4 surfaces form one layer of organic protective film.The nanometer Fe3O4, polyacrylamide and PDDA
Mass ratio is：20:0.1:0.1~20:0.3:0.3.
Preferably, the nanometer Fe3O4, poly amic acid and PDDA mass ratio be：10:
0.1:0.1。
A kind of preparation method of nano-magnetic flocculant for magnetic separation technique is：
(1) FeSO is prepared with deionized water4Solution, polyacrylamide is configured to the solution that mass fraction is 30%, gathered
Dimethyl diallyl ammonium chloride is configured to 30% solution, standby after being well mixed；
(2) under the conditions of 70 DEG C, deionized water is slowly dropped to FeSO4In solution, Fe (OH) is obtained2Colloid suspension；
(3) Fe (OH) obtained in step (2)2Cushioning liquid is added in colloid suspension, by Fe (OH)2Colloid is suspended
Liquid pH value is adjusted to 9~10, and oxygen is filled with according to 100~400mL/h speed, and is stirred, and makes Fe (OH)2Colloidal silica generates
Nanometer Fe3O4Particle；
(4) by the polyacrylamide solution of configuration and PDDA solution in step (1) according to institute
State nanometer Fe_3O_4：Poly amic acid：The mass ratio of PDDA is 10:0.1:0.1 ratio, slowly
Add the nanometer Fe that step (2) obtains3O4In particle, N is passed through2Gas shielded, and under the conditions of 40~50 DEG C, high-speed stirred；
(5) by after the complete reactant acetone precipitation of reaction, washing in step (4), 60 DEG C are dried to obtain finished product.
Further, the cushioning liquid is that the mass fraction that ammonium persulfate and sodium hydrogensulfite are prepared is 0.5%
Mixed solution.
The nano-magnetic flocculant can also use simultaneously with other flocculants and flocculation aid, increase flocculating effect, carry
Discharge water quality after the efficiency of high wastewater treatment and processing.
The application method of nano-magnetic flocculant provided by the invention is：
After nano-magnetic flocculant is dispersed into suspension by dispersant or nano material dispersion device, pass through chemicals dosing plant
It is added to according to 150mg/L~300mg/L nano-magnetic flocculant addition in pending enterprise wastewater, and passes through mixing
Device, nano-magnetic flocculant is set to evenly spread in waste water.After nano-magnetic flocculant is dispersed, nano-magnetic flocculant
Under the collective effect of flocculation aid, tiny flocculation group is formed, and enter magnetic separating device, in more than 2000Gs high-intensity magnetic field, shape
Into the micro- floc sedimentation of magnetic salvaged by disk or sludge retracting device, realize the separation of micro- magnetic floc sedimentation and water body, water outlet
Directly discharge or reuse.The micro- magnetic floc sedimentation separated by disk or sludge retracting device realizes magnetisable material through magnetic recovery system
With the separation of non magnetic sludge, and by high-speed shearing device by magnetisable material shearing refinement after recycling.
During the high-speed shearing device shearing, nanometer Fe is not destroyed3O4Particle surface organic functions film.
Nanometer Fe is prepared using ferrous sulfate3O4Particle, and coated using organic functions film, nanometer can be improved
Fe3O4The activity and micronized particles of particle, prevent nanometer Fe3O4Particle agglomeration and being oxidized causes that flocculating property weakens, magnetic subtracts
It is weak.
The polyacrylamide can serve as a kind of macromolecule water treatment flocculant product in itself, can specially adsorb water
In suspended particulate, play link bridging action between particles, fine grained is formed bigger floc sedimentation, and accelerate precipitation
Speed.The PDDA is strong cationic polyelectrolytes, and water stability is good, is used frequently as mixing
Solidifying agent.
Polyacrylamide and PDDA are in nanometer Fe3O4Particle surface be wrapped to form one layer it is organic
Functional membrane, that is, reach scattered nanometer Fe3O4Particle, avoid nanometer Fe3O4Particle is oxidized to α-Fe2O3, coagulation can be used as again
Agent, accelerate the flocculating effect of useless impurities in water, reduce the use of coagulant.
After the magnetic separating apparatus, fine filtering device can also be set to filter, make the waste water handled by magnetic separation technique
Refined filtration, draining water quality is further improved, reaches daily life quality of water standard.
Beneficial effects of the present invention：
(1) a kind of nano-magnetic flocculant for magnetic separation technique provided by the invention uses polyacrylamide and poly- two
Methyl diallyl ammonium chloride is in nanometer Fe3O4Particle surface forms one layer of organic protective film, reaches scattered nanometer Fe3O4Particle,
Prevent nanometer Fe3O4Particle is oxidized to α-Fe2O3Cause magnetic to weaken, make magnetic kind lose can magnetic recovery characteristic.
(2) polyacrylamide and poly- diformazan in a kind of nano-magnetic flocculant for magnetic separation technique provided by the invention
Base diallyl ammonium chloride is also used as coagulant, reduces the use of coagulant.
(3) a kind of preparation method of nano-magnetic flocculant for magnetic separation technique provided by the invention passes through FeSO4
Prepare Fe (OH)2Colloid, and pass through Oxidation of Fe (OH)2Colloid obtains epigranular, the nanometer Fe of good dispersion3O4Particle, and lead to
Cross the organic functions film that polyacrylamide and PDDA are formed to be coated, make its epigranular, no
Easily reunite, flocculating effect is more preferable.
Embodiment
The present invention is described in further detail with reference to embodiment, but the implementation of the present invention is not limited to this.
A kind of nano-magnetic flocculant for magnetic separation technique provided by the invention and preparation method thereof, for Magneto separate
In technology, the nano-magnetic flocculant is by nanometer Fe3O4, polyacrylamide and PDDA composition, and
In nanometer Fe3O4Particle surface forms one layer of organic protective film, makes nanometer Fe3O4Particle is not easy to be oxidized, and makes nanometer Fe3O4Particle
With by the characteristic of magnetic recovery.
The nanometer Fe3O4, polyacrylamide and PDDA mass ratio be：20:0.1:0.1
~20:0.3:0.3.
The preparation method of the nano-magnetic flocculant comprises the following steps：
(1) FeSO is prepared with deionized water4Solution, polyacrylamide is configured to the solution that mass fraction is 30%, gathered
Dimethyl diallyl ammonium chloride is configured to 30% solution, standby after being well mixed；
(2) under the conditions of 70 DEG C, deionized water is slowly dropped to FeSO4In solution, Fe (OH) is obtained2Colloid suspension；
(3) Fe (OH) obtained in step (2)2Cushioning liquid is added in colloid suspension, by Fe (OH)2Colloid is suspended
Liquid pH value is adjusted to 9~10, and oxygen is filled with according to 100~400mL/h speed, and is stirred, and makes Fe (OH)2Colloidal silica generates
Nanometer Fe3O4Particle；
(4) by the polyacrylamide solution of configuration and PDDA solution in step (1) according to institute
State nanometer Fe3O4：Poly amic acid：The mass ratio of PDDA is 10:0.1:0.1 ratio, slowly add
Enter the nanometer Fe that step (2) obtains3O4In particle, N is passed through2Gas shielded, and under the conditions of 40~50 DEG C, high-speed stirred；
(5) by after the complete reactant acetone precipitation of reaction, washing in step (4), 60 DEG C are dried to obtain finished product.
Embodiment 1
A kind of nano-magnetic flocculant for magnetic separation technique provided by the invention and preparation method thereof, for Magneto separate
In technology, the nano-magnetic flocculant is by nanometer Fe3O4, polyacrylamide and PDDA composition, and
In nanometer Fe3O4Particle surface forms one layer of organic protective film.The nanometer Fe3O4, polyacrylamide and the allyl of poly dimethyl two
The mass ratio of ammonium chloride is：20:0.1:0.1.
After nano-magnetic flocculant is dispersed into suspension by dispersant or nano material dispersion device, pass through chemicals dosing plant
Nano-magnetic flocculant addition according to 180mg/L is added in pending Mineral Processing Enterprises waste water, and by mixing arrangement,
Nano-magnetic flocculant is set to evenly spread in waste water.After nano-magnetic flocculant is dispersed, nano-magnetic flocculant is helping
Under the collective effect of solidifying agent, tiny flocculation group is formed, and enter magnetic separating device, in 2000Gs high-intensity magnetic field, the magnetic of formation
The recovery of micro- floc sedimentation, realizes the separation of micro- magnetic floc sedimentation and water body, and by the micro- floc sedimentation of the magnetic of recovery by high-speed shearing device by magnetic
Property material shearing refinement after recycling.
Embodiment 2
A kind of nano-magnetic flocculant for magnetic separation technique provided by the invention and preparation method thereof, for Magneto separate
In technology, the nano-magnetic flocculant is by nanometer Fe3O4, polyacrylamide and PDDA composition, and
In nanometer Fe3O4Particle surface forms one layer of organic protective film.The nanometer Fe3O4, polyacrylamide and the allyl of poly dimethyl two
The mass ratio of ammonium chloride is：20:0.3:0.3.
After nano-magnetic flocculant is dispersed into suspension by dispersant or nano material dispersion device, pass through chemicals dosing plant
Nano-magnetic flocculant addition according to 280mg/L is added in pending Mineral Processing Enterprises waste water, and by mixing arrangement,
Nano-magnetic flocculant is set to evenly spread in waste water.After nano-magnetic flocculant is dispersed, nano-magnetic flocculant is helping
Under the collective effect of solidifying agent, tiny flocculation group is formed, and enter magnetic separating device, in 2000Gs high-intensity magnetic field, the magnetic of formation
The recovery of micro- floc sedimentation, realizes the separation of micro- magnetic floc sedimentation and water body, and by the micro- floc sedimentation of the magnetic of recovery by high-speed shearing device by magnetic
Property material shearing refinement after recycling.
Embodiment 3
A kind of nano-magnetic flocculant for magnetic separation technique provided by the invention and preparation method thereof, for Magneto separate
In technology, the nano-magnetic flocculant is by nanometer Fe3O4, polyacrylamide and PDDA composition, and
In nanometer Fe3O4Particle surface forms one layer of organic protective film.The nanometer Fe3O4, polyacrylamide and the allyl of poly dimethyl two
The mass ratio of ammonium chloride is：10:0.1:0.1.
After nano-magnetic flocculant is dispersed into suspension by dispersant or nano material dispersion device, pass through chemicals dosing plant
Nano-magnetic flocculant addition according to 250mg/L is added in pending Mineral Processing Enterprises waste water, and by mixing arrangement,
Nano-magnetic flocculant is set to evenly spread in waste water.After nano-magnetic flocculant is dispersed, nano-magnetic flocculant is helping
Under the collective effect of solidifying agent, tiny flocculation group is formed, and enter magnetic separating device, in 2000Gs high-intensity magnetic field, the magnetic of formation
The recovery of micro- floc sedimentation, realizes the separation of micro- magnetic floc sedimentation and water body, and by the micro- floc sedimentation of the magnetic of recovery by high-speed shearing device by magnetic
Property material shearing refinement after recycling.
Waste water removal effect is as shown in table 1：
Table 1
It is described above, be only presently preferred embodiments of the present invention, any formal limitation not done to the present invention, it is every according to
Any simply modification, the equivalent variations made according to the technical spirit of the present invention to above example, each fall within the protection of the present invention
Within the scope of.
Claims (5)
1. a kind of nano-magnetic flocculant for magnetic separation technique, it is characterised in that the nano-magnetic flocculant is by nanometer
Fe3O4, polyacrylamide and PDDA composition, the polyacrylamide and poly dimethyl allyl
Ammonium chloride is in nanometer Fe3O4Surface forms one layer of organic protective film.
A kind of 2. nano-magnetic flocculant for magnetic separation technique according to claim 1, it is characterised in that：It is described to receive
Rice Fe3O4, polyacrylamide and PDDA mass ratio be：20:0.1:0.1~20:0.3:0.3.
A kind of 3. nano-magnetic flocculant for magnetic separation technique according to claim 1, it is characterised in that：It is described to receive
Rice Fe3O4, poly amic acid and PDDA mass ratio be：10:0.1:0.1.
4. a kind of preparation method of nano-magnetic flocculant for magnetic separation technique according to claim 3, its feature
It is, comprises the following steps：
（1）FeSO is prepared with deionized water4Solution, polyacrylamide is configured to the solution that mass fraction is 30%, poly dimethyl
Diallyl ammonium chloride is configured to 30% solution, standby after being well mixed；
（2）Under the conditions of 70 DEG C, deionized water is slowly dropped to FeSO4In solution, Fe is obtained（OH）2Colloid suspension；
（3）In step（2）In obtained Fe（OH）2Cushioning liquid is added in colloid suspension, by Fe（OH）2Colloid suspension pH
Value regulation is filled with oxygen to 9 ~ 10 according to 100 ~ 400mL/h speed, and stirs, and makes Fe（OH）2Colloidal silica generates nanometer
Fe3O4Particle；
（4）By step（1）The polyacrylamide solution and PDDA solution of middle configuration are received according to described
Rice Fe3O4：Poly amic acid：The mass ratio of PDDA is 10:0.1:0.1 ratio, it is slowly added to walk
Suddenly（2）Obtained nanometer Fe3O4In particle, N is passed through2Gas shielded, and under the conditions of 40 ~ 50 DEG C, high-speed stirred；
（5）By step（4）After the complete reactant acetone precipitation of middle reaction, washing, 60 DEG C are dried to obtain finished product.
5. a kind of preparation method of nano-magnetic flocculant for magnetic separation technique according to claim 4, its feature
It is：The cushioning liquid is the mixed solution that the mass fraction that ammonium persulfate and sodium hydrogensulfite are prepared is 0.5%.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114249485A (en) * | 2021-12-27 | 2022-03-29 | 上海电气电站环保工程有限公司 | Process for treating sludge in domestic sewage |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102432153A (en) * | 2011-11-18 | 2012-05-02 | 江苏大学 | Preparation method of magnetic deep sludge dehydration composite modifier |
| CN106495305A (en) * | 2016-11-14 | 2017-03-15 | 淮海工学院 | A kind of cationic composite magnetic flocculant and its application in the treatment of waste water |
-
2017
- 2017-11-03 CN CN201711071772.4A patent/CN107651743A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102432153A (en) * | 2011-11-18 | 2012-05-02 | 江苏大学 | Preparation method of magnetic deep sludge dehydration composite modifier |
| CN106495305A (en) * | 2016-11-14 | 2017-03-15 | 淮海工学院 | A kind of cationic composite magnetic flocculant and its application in the treatment of waste water |
Non-Patent Citations (1)
| Title |
|---|
| 程建辉: "可控粒径与形貌Fe3O4的制备及性能研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114249485A (en) * | 2021-12-27 | 2022-03-29 | 上海电气电站环保工程有限公司 | Process for treating sludge in domestic sewage |
| CN114249485B (en) * | 2021-12-27 | 2024-02-20 | 上海电气电站环保工程有限公司 | Treatment process of sludge in domestic sewage |
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Application publication date: 20180202 |