CN109499384A - A kind of method that hot water post-processing prepares high-flux nanofiltration membrane with pH regulation - Google Patents
A kind of method that hot water post-processing prepares high-flux nanofiltration membrane with pH regulation Download PDFInfo
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- CN109499384A CN109499384A CN201811393605.6A CN201811393605A CN109499384A CN 109499384 A CN109499384 A CN 109499384A CN 201811393605 A CN201811393605 A CN 201811393605A CN 109499384 A CN109499384 A CN 109499384A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/02—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
- B01D61/027—Nanofiltration
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
- B01D67/0006—Organic membrane manufacture by chemical reactions
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0081—After-treatment of organic or inorganic membranes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0081—After-treatment of organic or inorganic membranes
- B01D67/0083—Thermal after-treatment
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/48—Influencing the pH
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- Inorganic Chemistry (AREA)
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- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention belongs to macromolecular nano filtering technical field of membrane, provide a kind of method that hot water post-processing prepares high-flux nanofiltration membrane with pH regulation.The invention reside in during preparation nanofiltration membrane function separating layer, hot water post-processing is carried out to the nascent function separating layer after interfacial polymerization and carries out the cross-linked polymeric degree of adjusting function separating layer using pH, has obtained the high-flux nanofiltration membrane that sodium sulphate salt rejection rate is greater than 97%.In operating pressure 0.5MPa, under the conditions of operation temperature is 25 DEG C, the nanofiltration membrane that the hydrothermal solution through pH 14 is handled, flux has reached 201.7L/ (m2H), sodium sulphate rejection 97.2%.The present invention have it is easy to operate, low in raw material price and be easy to technique amplification the advantages of.It can be applied not only in nanofiltration membrane preparation process, the post-processing and regulation that can also react for other membrane fussions provide new approach.
Description
Technical field
The invention belongs to macromolecular nano filtering technical field of membrane, and in particular to a kind of post-processing of hot water and pH regulation preparation high pass
The method for measuring nanofiltration membrane.
Background technique
Nanofiltration is the pressure-actuated novel membrane separation technique of one kind to grow up since the 1980s.It receives
For the characteristic of filter membrane between reverse osmosis membrane and ultrafiltration membrane, but compared with the former, nanofiltration membrane has high pass at lower pressures
The advantages of amount and high retention, therefore in the softening of hard water, the separation of small organic molecule, the removal of heavy metal and bio-pharmaceuticals row
The purification of industry and concentration etc. have a wide range of applications.
Currently, commercially general polyamide nanofiltration membrane is a kind of composite membrane being made of supporting layer and separating layer, lead to
Amount is generally in 10L/ (m2Hbar) left and right.Supporting layer mainly makes film have certain mechanical strength, and separating layer is film hair
The core of its centrifugation is waved, therefore also becomes the emphasis of nanofiltration membrane research.In general, separating layer mainly passes through interfacial polymerization shape
At aperture be 1 ran, thin layer of the thickness in dozens to a few hundred nanometers.In order to promote the performance of nanofiltration membrane, many researchs
Persons focus mainly on the selection to separating layer polymerized monomer, the addition of nano material and how to make separating layer is thinner to grind
Study carefully.
While keeping high retention, the flux for constantly promoting nanofiltration membrane is an important directions of nanofiltration membrane development.
Wang etc. (Nature.Communications.9 (2018) 1-9) be prepared for it is a kind of using nanoparticle as sacrifice template lure
The ultra-thin separating layer nanofiltration membrane with a large amount of pleated structures of building is led, ultra-thin separating layer is effectively promoted in these pleated structures
Effective filtration area, reduce water by resistance, to greatly improve the separation flux of nanofiltration membrane.This is novel
Nanofiltration membrane significantly improves the separation flux of nanofiltration membrane, reaches 53L/ while keeping to 95% or more divalent ion retention
(m2It hbar), is 5-8 times of traditional nanofiltration membrane considerably beyond traditional nanofiltration membrane.
Chinese patent " ultra-high throughput nanofiltration membrane and preparation method thereof " (publication number CN106139922A) by piperazine and
On the basis of the mix monomer of fluorochemical monomer, adds sodium hypochlorite and sodium hydroxide and oxidation pre-treatment is carried out to aqueous phase solution, with
And oxidative work-up is carried out to the nanofiltration membrane of the nascent state obtained after interfacial polymerization, in the premise for guaranteeing sodium sulphate salt rejection rate
Under, having obtained pure water flux can achieve 22L/ (m2Hbar), the nanofiltration membrane of sodium sulphate salt rejection rate 90.7%, the nanofiltration membrane
And there is certain chlorine resistance.Chinese patent " using the chlorine-resistant nanofiltration membrane and preparation method thereof of hybrid diamine monomer " (publication number
CN105771700A a kind of preparation method of chlorine-resistant nanofiltration membrane using hybrid diamine monomer) is disclosed comprising six will be contained
Monomer 2,2 '-two (trifluoromethyl -2,2,2 1- hydroxyl -1-,-trifluoroethyl) -4,4 '-methylenes of fluorine isopropyl alcohol groups nanofiltration membrane
Base dianil and piperazine are hybridly prepared into aqueous phase solution, by the interfacial polymerization on the counterdie of ultrafiltration membrane, and through Overheating Treatment and
Oxidation processes have obtained the nanofiltration membrane of high-throughput, high retention, high chlorine resistance.
Researchers seldom pay close attention to the heat treatment stages after interfacial polymerization at present, are usually all to carry out hot place by baking oven
Reason.For the nanofiltration membrane for preparing while having high-throughput and height to retain, the heat treatment after interfacial polymerization is studied in detail,
Propose a kind of method that hot water post-processing prepares high-flux nanofiltration membrane with pH regulation.
Summary of the invention
The present invention for overcome the deficiencies in the prior art, provides a kind of new interfacial polymerization heat treatment method, and in heat
During water post-processes, is regulated and controled using aqueous solution pH, be prepared for the nanofiltration membrane of high flux and high retention.This method relative to
Traditional baking oven heat treatment, there is heat transfer to stablize, uniform feature, it is most important that provide possibility for the regulation of pH.
Technical solution of the present invention:
A kind of preparation method of high throughput high desalination nanofiltration membrane includes the hot water post-processing and benefit of interface polymerization reaction
It is carried out regulating and controlling further polymerization with pH, specific steps include:
(1) it is for the aqueous phase monomers solution of 0.01-3%w/v and uniform by ultrasonic mixing to prepare piperazine content；
(2) it is for the organic phase monomer solution of 0.02-1%w/v and equal by ultrasonic mixing to prepare pyromellitic trimethylsilyl chloride content
It is even；
(3) solution of pH0-14 is prepared with all kinds of soda acids such as hydrochloric acid, nitric acid, sulfuric acid, sodium hydroxide respectively, and be heated to
10-80℃；
(4) polyether sulfone basement membrane is fixed on plastic ring, aqueous phase solution is poured on membrane surface, basement membrane is completely covered, it is quiet
After setting 0.2-10 minutes, extra water phase is outwelled and uses compressed air purging membrane surface to surface without water droplet, then will be organic
Phase solution is poured on membrane surface, and after standing 0.2-10 minutes, extra organic phase is outwelled；
(5) when the remaining organic phase of film surface vapors away, it is 10-80 DEG C that film, which is immersed temperature, the aqueous solution of pH0-14
In, stand 1-15 minutes；
(6) film is taken out, after being rinsed with deionized water, film is immersed in deionized water.
A kind of method that hot water post-processing and pH regulation according to the present invention prepare high-flux nanofiltration membrane, the step
(2) the aqueous solution pH in for hot water post-processing is 0-14.
A kind of method that hot water post-processing and pH regulation according to the present invention prepare high-flux nanofiltration membrane, the step
(3) basement membrane in is the materials such as polyether sulfone, polysulfones, polyvinyl chloride.
A kind of method that hot water post-processing and pH regulation according to the present invention prepare high-flux nanofiltration membrane, the step
(1) organic phase in is one of n-hexane, toluene, benzene, isoparaffin IsoparG etc. or several mixtures, reactive amines
For one of piperazine, m-phenylene diamine (MPD), polyethyleneimine etc. or several mixtures, Active Chlorine is pyromellitic trimethylsilyl chloride, isophthalic
One of dimethyl chloride, paraphthaloyl chloride etc. or several mixtures.
A kind of method that hot water post-processing and pH regulation according to the present invention prepare high-flux nanofiltration membrane, further,
The activity of the reactive amines aqueous phase solution for preparing mass concentration 0.2%-1% respectively and 0.1%-0.25% in the step (1)
Acyl chlorides organic phase solution.
A kind of method that hot water post-processing and pH regulation according to the present invention prepare high-flux nanofiltration membrane, further,
The optimum condition that hot water post-processes in the step (4) are as follows: 30-70 DEG C of temperature, pH0-14, time 3-8 minute.
Compared with traditional baking oven heat treatment, present invention has an advantage that the specific heat capacity of hot water post-processing water is big, has and pass
Thermostabilization, uniform feature, while water easily form moisture subchannel in the separating layer that interfacial polymerization is formed as medium, prevent
Only separating layer structure collapses, and in addition also provides possibility for the regulation of pH；In addition have it is easy to operate, low in raw material price and
The advantages of being easy to technique amplification.
Detailed description of the invention
Fig. 1 is the scanning electron microscope (SEM) photograph (front) of the gained film after step (1) to (5) of embodiment 1；
Fig. 2 is the scanning electron microscope (SEM) photograph (section) of the gained film after step (1) to (5) of embodiment 1；
Fig. 3 is the scanning electron microscope (SEM) photograph (front) of the gained film after step (1) to (5) of embodiment 6；
Fig. 4 is the scanning electron microscope (SEM) photograph (section) of the gained film after step (1) to (5) of embodiment 6；
Specific embodiment
The calculation formula of membrane flux is such as shown in (1)
Wherein J is the flux (L/ (m of film2H)), V is the volume (L) for the permeate being collected into, and A is the effective area of film
(m2), T is the time (h) required for being collected into the permeate of volume.
The cutoff performance calculation method of film is such as shown in (2).
Wherein R is the rejection of film, CpFor the concentration through side, CfFor the concentration of feed side.
The concentration of electrolyte solution uses conductivity meter measurement to penetrate the conductivity of side and feed side first, then passes through electricity
The standard curve of electrolyte solution is fitted to calculating its concentration, and then finds out its rejection.All films measure 3 times,
It is averaged to obtain result.
Embodiment 1
Polyether sulfone basement membrane is fixed on plastic ring, the aqueous phase solution containing 1% piperazine is poured on membrane surface, is completely covered
Extra water phase is outwelled after standing 3 minutes and uses compressed air purging membrane surface to surface without water droplet, then will contained by basement membrane
The hexane solution of 0.15% pyromellitic trimethylsilyl chloride is poured on membrane surface, after standing 15 seconds, extra organic phase is outwelled, film is worked as
When organic phase solution remained on surface vapors away, it is 50 DEG C that film, which is immersed temperature, after carrying out hot water in the aqueous solution that pH is 7
Reason stands 5 minutes, takes out and obtains nanofiltration membrane, the nanofiltration membrane of preparation is immersed to be measured in deionized water.
Under the conditions of 25 DEG C of operation temperature and operating pressure 0.5MPa, its section is tested with the aqueous sodium persulfate solution of 2000ppm
Stay performance.The pure water flux of nanofiltration membrane is 54.1L/ (m2H), sodium sulphate salt rejection rate is 97.7%.
Embodiment 2~5
Other than the pH of hot water post-processing is respectively adopted 9,11,13 and 14, other steps are same as Example 1, operating
25 DEG C of temperature, under the conditions of operating pressure 0.5MPa, are tested its cutoff performance with 2000ppm aqueous sodium persulfate solution.The result is shown under
Table:
Embodiment 6~10
Other than the pH of hot water post-processing is respectively adopted 0,0.3,1,3 and 5, other steps are same as Example 1, operating
25.0 DEG C of temperature, under the conditions of operating pressure 0.5MPa, are tested its cutoff performance with 2000ppm aqueous sodium persulfate solution.The result is shown in
Following table:
In addition to aqueous phase solution piperazine concentration is 0.5%, the pH of hot water post-processing is other steps and 1 phase of embodiment outside 0
Together, under the conditions of 25.0 DEG C of operation temperature and operating pressure 0.5MPa, its rejection is tested with 2000ppm aqueous sodium persulfate solution
Energy.The pure water flux of nanofiltration membrane is 191.0L/ (m2H), sodium sulphate salt rejection rate is 97.4%.
Embodiment 11
In addition to aqueous phase solution piperazine concentration is 0.5%, the pH of hot water post-processing is other steps and 1 phase of embodiment outside 14
Together, under the conditions of 25 DEG C of operation temperature and operating pressure 0.5MPa, its cutoff performance is tested with 2000ppm aqueous sodium persulfate solution.
The pure water flux of nanofiltration membrane is 201.7L/ (m2Hbar), sodium sulphate salt rejection rate is 97.2%.
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
Member further can also be retouched and be improved to the present invention under the premise of not departing from design of the invention, these improvement
It also should be considered as in protection scope of the present invention with retouching.
Claims (6)
1. a kind of method that hot water post-processing and pH regulation prepare high-flux nanofiltration membrane, which comprises the following steps:
(1) the reactive amines aqueous phase solution of mass concentration 0.01%-3% and the active acyl chloride organic phase of 0.02%-1% are prepared respectively
Solution；
(2) aqueous solution of pH0-14 is prepared with all kinds of soda acids such as hydrochloric acid, nitric acid, sulfuric acid, sodium hydroxide respectively；
(3) polysulfones basement membrane is fixed on plastic ring first, aqueous phase solution is poured on membrane surface, basement membrane is completely covered, stood
0.2-10 minutes, extra water phase is outwelled and uses compressed air purging membrane surface to surface without water droplet；It mixes again by organic
Liquid is poured on membrane surface, and after standing 0.2-10 minutes, extra organic phase is outwelled；
(4) when the remaining organic phase of film surface vapors away, film is immersed in the aqueous solution of 10-80 DEG C of temperature and pH0-14, it is quiet
It sets 1-15 minutes；
(5) film is taken out, after being rinsed with deionized water, film is immersed in deionized water.
2. the method that a kind of hot water post-processing according to claim 1 and pH regulation prepare high-flux nanofiltration membrane, feature
It is, the aqueous solution pH in the step (2) for hot water post-processing is 0-14.
3. the method that a kind of hot water post-processing according to claim 1 and pH regulation prepare high-flux nanofiltration membrane, feature
It is, the basement membrane in the step (3) is the materials such as polyether sulfone, polysulfones, polyvinyl chloride.
4. the preparation method of high throughput high desalination nanofiltration membrane according to claim 1, which is characterized in that the step (1)
In organic phase be one of n-hexane, toluene, benzene, isoparaffin IsoparG etc. or several mixtures, reactive amines are piperazine
One of piperazine, m-phenylene diamine (MPD), polyethyleneimine etc. or several mixtures, Active Chlorine are pyromellitic trimethylsilyl chloride, isophthalic diformazan
One of acyl chlorides, paraphthaloyl chloride etc. or several mixtures.
5. the preparation method of high throughput high desalination nanofiltration membrane according to claim 1, which is characterized in that the step (1)
In the active acyl chloride of the reactive amines aqueous phase solution and 0.1%-0.25% for preparing mass concentration 0.2%-1% respectively organic mix
Liquid.
6. the preparation method of high throughput high desalination nanofiltration membrane according to claim 1, which is characterized in that the step (4)
The optimum condition of middle hot water post-processing are as follows: 30-70 DEG C of temperature, pH0-14, time 3-8 minute.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114870645A (en) * | 2022-03-17 | 2022-08-09 | 浙江理工大学 | Method for improving flux of composite reverse osmosis membrane prepared by interfacial polymerization method |
| CN117065575A (en) * | 2023-10-16 | 2023-11-17 | 蓝星（杭州）膜工业有限公司 | Nanofiltration membrane and preparation method and application thereof |
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| JPS63287507A (en) * | 1987-05-20 | 1988-11-24 | Toray Ind Inc | Production of semipermeable composite membrane |
| CN107349804A (en) * | 2017-07-13 | 2017-11-17 | 中国科学院生态环境研究中心 | A kind of preparation method of high flux anti-acid NF membrane |
| CN107899437A (en) * | 2017-11-21 | 2018-04-13 | 贵阳时代沃顿科技有限公司 | A kind of high-performance water-oil separationg film based on interfacial polymerization and preparation method thereof |
| WO2018192549A1 (en) * | 2017-04-19 | 2018-10-25 | The University Of Hong Kong | Thin film composite membrane with nano-sized bubbles having enhanced membrane permeability, preparation methods and uses thereof |
-
2018
- 2018-11-21 CN CN201811393605.6A patent/CN109499384A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63287507A (en) * | 1987-05-20 | 1988-11-24 | Toray Ind Inc | Production of semipermeable composite membrane |
| WO2018192549A1 (en) * | 2017-04-19 | 2018-10-25 | The University Of Hong Kong | Thin film composite membrane with nano-sized bubbles having enhanced membrane permeability, preparation methods and uses thereof |
| CN107349804A (en) * | 2017-07-13 | 2017-11-17 | 中国科学院生态环境研究中心 | A kind of preparation method of high flux anti-acid NF membrane |
| CN107899437A (en) * | 2017-11-21 | 2018-04-13 | 贵阳时代沃顿科技有限公司 | A kind of high-performance water-oil separationg film based on interfacial polymerization and preparation method thereof |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114870645A (en) * | 2022-03-17 | 2022-08-09 | 浙江理工大学 | Method for improving flux of composite reverse osmosis membrane prepared by interfacial polymerization method |
| CN117065575A (en) * | 2023-10-16 | 2023-11-17 | 蓝星（杭州）膜工业有限公司 | Nanofiltration membrane and preparation method and application thereof |
| CN117065575B (en) * | 2023-10-16 | 2024-01-30 | 蓝星（杭州）膜工业有限公司 | Nanofiltration membrane and preparation method and application thereof |
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Application publication date: 20190322 |