CN111196621A - Foam for treating metallurgical oily wastewater and preparation method thereof - Google Patents
Foam for treating metallurgical oily wastewater and preparation method thereof Download PDFInfo
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- CN111196621A CN111196621A CN202010064414.6A CN202010064414A CN111196621A CN 111196621 A CN111196621 A CN 111196621A CN 202010064414 A CN202010064414 A CN 202010064414A CN 111196621 A CN111196621 A CN 111196621A
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- Prior art keywords
- foam
- porous matrix
- oil
- oily wastewater
- water
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- 239000006260 foam Substances 0.000 title claims abstract description 53
- 239000002351 wastewater Substances 0.000 title claims abstract description 22
- 238000002360 preparation method Methods 0.000 title abstract description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 27
- 239000011159 matrix material Substances 0.000 claims abstract description 16
- PUVAFTRIIUSGLK-UHFFFAOYSA-M trimethyl(oxiran-2-ylmethyl)azanium;chloride Chemical compound [Cl-].C[N+](C)(C)CC1CO1 PUVAFTRIIUSGLK-UHFFFAOYSA-M 0.000 claims abstract description 9
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 229920000877 Melamine resin Polymers 0.000 claims description 8
- 239000003513 alkali Substances 0.000 claims description 8
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical group NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims description 8
- 239000000758 substrate Substances 0.000 claims description 8
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 238000000034 method Methods 0.000 claims description 6
- 238000004506 ultrasonic cleaning Methods 0.000 claims description 4
- 239000011148 porous material Substances 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 3
- 238000004140 cleaning Methods 0.000 claims description 2
- 239000012153 distilled water Substances 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 238000007781 pre-processing Methods 0.000 claims description 2
- 230000035484 reaction time Effects 0.000 claims description 2
- 238000000926 separation method Methods 0.000 abstract description 17
- 239000000839 emulsion Substances 0.000 abstract description 11
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 239000003921 oil Substances 0.000 description 20
- 235000019198 oils Nutrition 0.000 description 20
- 239000000243 solution Substances 0.000 description 9
- 238000012986 modification Methods 0.000 description 6
- 230000004048 modification Effects 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- 230000007613 environmental effect Effects 0.000 description 3
- 239000010720 hydraulic oil Substances 0.000 description 3
- 239000010687 lubricating oil Substances 0.000 description 3
- 239000002569 water oil cream Substances 0.000 description 3
- NHTMVDHEPJAVLT-UHFFFAOYSA-N Isooctane Chemical compound CC(C)CC(C)(C)C NHTMVDHEPJAVLT-UHFFFAOYSA-N 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- JVSWJIKNEAIKJW-UHFFFAOYSA-N dimethyl-hexane Natural products CCCCCC(C)C JVSWJIKNEAIKJW-UHFFFAOYSA-N 0.000 description 2
- 239000000706 filtrate Substances 0.000 description 2
- 150000007974 melamines Chemical class 0.000 description 2
- 238000005272 metallurgy Methods 0.000 description 2
- 239000003094 microcapsule Substances 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 238000001612 separation test Methods 0.000 description 2
- ITYXXSSJBOAGAR-UHFFFAOYSA-N 1-(methylamino)-4-(4-methylanilino)anthracene-9,10-dione Chemical compound C1=2C(=O)C3=CC=CC=C3C(=O)C=2C(NC)=CC=C1NC1=CC=C(C)C=C1 ITYXXSSJBOAGAR-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000007385 chemical modification Methods 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000009851 ferrous metallurgy Methods 0.000 description 1
- 238000000769 gas chromatography-flame ionisation detection Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000008204 material by function Substances 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000007764 o/w emulsion Substances 0.000 description 1
- 235000019476 oil-water mixture Nutrition 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005289 physical deposition Methods 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 235000010482 polyoxyethylene sorbitan monooleate Nutrition 0.000 description 1
- 229920000053 polysorbate 80 Polymers 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Images
Classifications
-
- 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
- C02F1/40—Devices for separating or removing fatty or oily substances or similar floating material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
- B01D17/02—Separation of non-miscible liquids
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
- Water Treatment By Sorption (AREA)
Abstract
The invention discloses a foam for treating metallurgical oily wastewater, which comprises a porous matrix, wherein the porous matrix is provided with three-dimensional through holes, and the surface of the porous matrix is grafted with 2, 3-epoxypropyl trimethyl ammonium chloride. The second purpose of the invention is to provide a preparation method of the foam. The invention has the beneficial effects that: the prepared foam has the advantages of complete appearance, good mechanical property, high water passing speed, high separation efficiency of the oil-containing emulsion and good repeatability.
Description
Technical Field
The invention belongs to the field of functional materials, and particularly relates to foam for treating metallurgical oily wastewater and a preparation method thereof.
Background
The treatment of oily wastewater is always a difficult problem in the field of environmental protection. Due to the different properties, the oily and aqueous components generally need to be treated separately. With the stricter environmental requirements, the implementation of new national ultra-clean discharge standards becomes a more challenge in treating oily wastewater to reach high discharge standards. In the prior art, some available oil-water separation materials deposit functional particles or coatings or graft functional molecules on the surface of a porous substrate in a physical deposition or chemical bonding mode so as to modify the surface of the substrate and achieve the purpose of changing the surface hydrophilicity and hydrophobicity. However, these materials have one or more disadvantages such as complicated preparation, poor stability, low separation efficiency, and high price, and are difficult to be popularized and used. On the other hand, the production technology of cold-rolled strip steel in the ferrous metallurgy process is continuously developed, the product varieties show diversified trends, the components of cold-rolled oily wastewater are increasingly complex, the treatment difficulty and the treatment cost are continuously increased, and particularly the wastewater of cold-rolled oily wastewater and emulsion is extremely difficult to treat. Therefore, the development of a new oil-water separation material to meet the treatment requirement of the metallurgical oily wastewater has important economic and environmental significance.
Disclosure of Invention
In view of the above, an object of the present invention is to provide a foam for treating oily wastewater in metallurgy. The technical scheme is as follows:
the foam for treating the oily metallurgical wastewater is characterized by comprising a porous matrix, wherein the porous matrix is provided with three-dimensional through holes, and the surface of the porous matrix is grafted with 2, 3-epoxypropyltrimethylammonium chloride.
Preferably, the porous substrate is melamine foam.
Preferably, the porous substrate has an average pore diameter of 50 μm.
The invention also aims to provide a preparation method of the foam for treating the oily wastewater in metallurgy. The technical scheme is as follows:
the preparation method is characterized by comprising the following steps:
firstly, preprocessing the porous matrix to clean the surface of the porous matrix;
step two, immersing the pretreated porous matrix into an alkali solution, adding 2, 3-epoxypropyltrimethylammonium chloride, and stirring for reaction;
and step three, carrying out post-treatment on the porous matrix reacted in the step two to obtain the foam.
Preferably, in the first step, the porous substrate is immersed in an ethanol solution for ultrasonic cleaning, and then taken out and dried.
Preferably, in the second step, the alkali solution is a 7% sodium hydroxide solution.
Preferably, in the second step, the temperature of the alkali solution is maintained at 50 ℃.
Preferably, in the second step, the reaction time is 5 hours.
As a preferable technical scheme, the post-treatment is to remove excessive alkali and 2, 3-epoxypropyltrimethylammonium chloride on the surface of the foam by using distilled water for cleaning.
Compared with the prior art, the invention has the beneficial effects that: the prepared foam has complete appearance and good mechanical property; the water passing speed is high and can reach 95000 L.m-2·h-1(ii) a The separation efficiency of the oil-containing emulsion is high; the repeatability is good, and the oil-water separation efficiency is still higher than 99% after multiple times of separation.
Drawings
FIG. 1 is a reaction formula for surface modification of melamine foam;
FIG. 2 is a schematic structural view of a foam before modification (1a) and after modification (1b) under a scanning electron microscope;
FIG. 3 is an appearance view before and after the separation of the emulsion and a picture under a microscope;
FIG. 4 is a graph showing the change in separation efficiency of the foam after repeated separations.
Detailed Description
The present invention will be further described with reference to the following examples and the accompanying drawings.
Examples
1. Preparation of the foam
A preparation method of foam for treating oily wastewater comprises the following steps:
pretreatment of melamine foam: melamine foam with the thickness of 1-5cm and three-dimensional through holes is selected as a porous base material, and the average pore size of the porous base material is about 50 micrometers. The foam was processed to the desired size and then the different sized foams were sonicated in ethanol solution and subjected to ultrasonic cleaning for 30 minutes. Then taking out the foam, and drying the foam in an oven at 50 ℃;
chemical modification of melamine foam: respectively immersing the dried melamine foams with different sizes into a sodium hydroxide solution with the mass concentration of 7%, keeping the solution temperature at 50 ℃, then adding different amounts of 2, 3-epoxypropyltrimethylammonium chloride (GTMAC) into the sodium hydroxide solution, wherein the mass ratio of the GTMAC to the melamine foam is 1:1, and stirring for 5 hours for reaction, wherein the reaction process of the reaction is shown in figure 1;
subsequently, the foam was taken out and the surface of the foam was washed with clean water for residual sodium hydroxide and 2, 3-epoxypropyltrimethylammonium chloride, and dried to complete the modification.
2. Characterization of foam physical Properties
2.1 morphology
The foam before and after modification was observed under a scanning electron microscope, and the morphology thereof was shown in FIG. 1a and FIG. 1b, respectively. It can be seen that the foam morphology after modification has not changed significantly.
2.2 contact Angle
In the air, the dynamic contact angle of a water drop on the surface of the modified foam is 0 degrees, which shows that the wettability is good; for the organic solvent isooctane, the underwater contact angle of the organic solvent isooctane on the surface of the modified foam is 160 degrees. The pre-wetted foam was placed in the oil and then removed and placed in the water, whereupon the oil was observed to immediately spread from the foam, and no oil droplets were observed to be adsorbed on the surface of the foam to the naked eye.
3. Verification of separation effect
3.1 preparation of an oil-water emulsion
To prepare a surfactant-free oil-water emulsion, 20mL of lubricating oil was added to 180mL of water, and the mixture was sonicated for 30 min. To prepare a surfactant-stabilized oil-in-water emulsion, 0.02g tween 80 was dissolved in 200mL of water, and 2.0mL of lubricating oil (rosen LOSH) antiwear hydraulic oil No. 32, commercial code: 25154759762), and then the mixed solution was vigorously stirred for 3 hours. The emulsion preparation method of other oil (great wall antiwear hydraulic oil L-HM46 rail oil mechanical oil No. 32, commodity No. 51274543333; Meilian brand previtan L-HM46 antiwear hydraulic oil No. 32, commodity No. 52733106796) refers to lubricating oil.
3.2 oil-water separation test
The non-chemically modified melamine foam and the chemically modified melamine foam were each held between two glass containers having a diameter of 34 mm. All of the foams described above were pre-wetted with water prior to the oil-water separation test. The mixed liquid of oil and water is poured into a container and then gravity is relied upon to separate the oil and water. The filtered water was collected, and the content of oil contained therein was detected by gas chromatography-flame ionization [ GC/FID; 5890(HP) and 7890(Agilent) ]. The oil removal rate in the filtrate in surfactant stabilised oil-in-water emulsions was determined by measuring the oil content in the feed and the corresponding filtrate using a UV-Vis spectrophotometer (Evolution 201, Thermo Scientific). Wherein the oil was stained with sudan blue II.
The modified foam can separate oil and water of different kinds of oily wastewater, and the oil content in the separated water is measured to be less than 1 PPM. The modified foam is measured to have an ultra-fast water passing speed which can reach 95000 L.m-2·h-1. Separating 1L of oil-water mixture, and testing through continuous experiments to ensure that the oil content in water is still less than 1PPM and the water passing rate is not obviously changed.
The modified foam also allows for separation of waste water containing oil emulsions. The prepared foam is compressed, the compressed modified foam is fixed in a syringe with the diameter of 19mm, and then the emulsion wastewater with oil content is separated. The size of the separated emulsion is less than 20 μm. After separation, the oil content in the water was less than 3 ppm. As shown in fig. 3, the wastewater of the oil-containing emulsion was milky in appearance, microcapsules were visible under a microscope, the appearance of the separated water was transparent, and no microcapsules were visible under a microscope.
After 1L of the emulsion wastewater was separated, ultrasonic cleaning was performed with ethanol for 20 minutes. Then the separation is repeated for 10 times, and the oil-water separation efficiency is still higher than 99%, as shown in figure 4. After multiple times of separation, the mechanical property, the wettability and the oil-water emulsion separation characteristic of the modified foam are basically unchanged.
Finally, it should be noted that the above-mentioned description is only a preferred embodiment of the present invention, and those skilled in the art can make various similar representations without departing from the spirit and scope of the present invention.
Claims (9)
1. A foam for treating metallurgical oily wastewater, which is characterized in that: the porous substrate is provided with three-dimensional through holes, and the surface of the porous substrate is grafted with 2, 3-epoxypropyltrimethylammonium chloride.
2. The foam for treating metallurgical oily wastewater according to claim 1, which is characterized in that: the porous substrate is melamine foam.
3. The foam for treating metallurgical oily wastewater according to claim 1, which is characterized in that: the porous matrix has an average pore diameter of 50 μm.
4. A process for preparing the foam of claim 2, characterized by the following steps:
firstly, preprocessing the porous matrix to clean the surface of the porous matrix;
step two, immersing the pretreated porous matrix into an alkali solution, adding 2, 3-epoxypropyltrimethylammonium chloride, and stirring for reaction;
and step three, carrying out post-treatment on the porous matrix reacted in the step two to obtain the foam.
5. The method of claim 4, wherein: in the first step, the porous matrix is immersed in an ethanol solution for ultrasonic cleaning, and then taken out and dried.
6. The method of claim 4, wherein: in the second step, the alkali solution is a sodium hydroxide solution with a mass concentration of 7%.
7. The method of claim 6, wherein: in the second step, the temperature of the alkali solution is kept at 50 ℃.
8. The method of claim 7, wherein: in the second step, the reaction time is 5 h.
9. The method of claim 4, wherein: the post-treatment is to remove excessive alkali and 2, 3-epoxypropyltrimethylammonium chloride on the surface of the foam by using distilled water for cleaning.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010064414.6A CN111196621B (en) | 2020-01-20 | 2020-01-20 | Foam for treating metallurgical oily wastewater and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010064414.6A CN111196621B (en) | 2020-01-20 | 2020-01-20 | Foam for treating metallurgical oily wastewater and preparation method thereof |
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| CN111196621A true CN111196621A (en) | 2020-05-26 |
| CN111196621B CN111196621B (en) | 2022-04-22 |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110293374A1 (en) * | 2010-05-27 | 2011-12-01 | Basf Se | Oil-absorbent polyurethane sponges with good mechanical properties |
| CN106589201A (en) * | 2015-10-15 | 2017-04-26 | 中国科学院过程工程研究所 | Hydrophilic modification method of polystyrene material and product thereof |
| CN106955676A (en) * | 2017-03-18 | 2017-07-18 | 华南理工大学 | A kind of temperature-responsive water-oil separating foam and preparation method thereof |
-
2020
- 2020-01-20 CN CN202010064414.6A patent/CN111196621B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110293374A1 (en) * | 2010-05-27 | 2011-12-01 | Basf Se | Oil-absorbent polyurethane sponges with good mechanical properties |
| CN106589201A (en) * | 2015-10-15 | 2017-04-26 | 中国科学院过程工程研究所 | Hydrophilic modification method of polystyrene material and product thereof |
| CN106955676A (en) * | 2017-03-18 | 2017-07-18 | 华南理工大学 | A kind of temperature-responsive water-oil separating foam and preparation method thereof |
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| CN111196621B (en) | 2022-04-22 |
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Application publication date: 20200526 Assignee: GUANGZHOU SHANGTONG ENVIRONMENTAL PROTECTION TECHNOLOGY Co.,Ltd. Assignor: Chongqing University of Science & Technology Contract record no.: X2023980054320 Denomination of invention: A foam used for treating metallurgical oily wastewater and its preparation method Granted publication date: 20220422 License type: Common License Record date: 20240103 Application publication date: 20200526 Assignee: Guangzhou Jinhan Environmental Protection Technology Co.,Ltd. Assignor: Chongqing University of Science & Technology Contract record no.: X2023980054316 Denomination of invention: A foam used for treating metallurgical oily wastewater and its preparation method Granted publication date: 20220422 License type: Common License Record date: 20240103 |
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Application publication date: 20200526 Assignee: Yantai Junyu Energy Conservation and Environmental Protection Equipment Co.,Ltd. Assignor: Chongqing University of Science & Technology Contract record no.: X2024980000522 Denomination of invention: A foam for treating metallurgical oily wastewater and its preparation method Granted publication date: 20220422 License type: Common License Record date: 20240111 |
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