CN107213796A - A kind of preparation method of the novel polyetherimide NF membrane containing modified graphene oxide - Google Patents
A kind of preparation method of the novel polyetherimide NF membrane containing modified graphene oxide Download PDFInfo
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- CN107213796A CN107213796A CN201710668163.0A CN201710668163A CN107213796A CN 107213796 A CN107213796 A CN 107213796A CN 201710668163 A CN201710668163 A CN 201710668163A CN 107213796 A CN107213796 A CN 107213796A
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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
- B01D67/0079—Manufacture of membranes comprising organic and inorganic components
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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
- 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
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/58—Other polymers having nitrogen in the main chain, with or without oxygen or carbon only
- B01D71/62—Polycondensates having nitrogen-containing heterocyclic rings in the main chain
- B01D71/64—Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/02—Details relating to pores or porosity of the membranes
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- Separation Using Semi-Permeable Membranes (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Abstract
The invention discloses a kind of modified graphene oxide based on polyethylene glycol and applied to the preparation method for preparing novel polyetherimide NF membrane.The present invention first passes through poly ethyldiol modified graphene oxide and obtains modified graphene oxide, then modified graphene oxide is added in PEI preparation liquid by novel polyetherimide NF membrane of the submergence phase inversion preparation containing modified graphene oxide.It is an advantage of the invention that improving the pore structure of PEI using the reticulated porous structures of modified graphene oxide, the fluid duct that solvent is passed through is conducive to the large scale solute molecule in effectively catching organic solution and increasing in film.When the adding proportion of modified graphene oxide is 1.0 wt%, the permeation flux and rejection that NF membrane can be achieved are improved simultaneously.
Description
Technical field
The present invention relates to a kind of novel polyetherimide NF membrane containing modified graphene oxide is prepared, high selectivity is realized
Separating property.The novel polyetherimide NF membrane of the present invention, is increased using the nanometer porous structure of modified graphene oxide
The porosity of polyetherimde films is added, with the large scale solute molecule in effectively catching solution and has increased and be conducive to solvent in film
The fluid duct of transmission, realizes that the permeation flux and rejection of NF membrane are improved simultaneously.
Background technology
In field of waste water treatment of today, membrane separation technique is still a kind of important technology, and have a wide range of applications city
Field and prospect.Membrane separation technique mainly include micro-filtration, ultrafiltration, nanofiltration, counter-infiltration, positive infiltration, liquid film separation, gaseous jet simulation,
Electrodialysis etc..Wherein, nanofiltration is the new membrane separation technique between ultrafiltration and counter-infiltration, and molecular cut off is in 200-1000
In the range of dalton.Compared with milipore filter and reverse osmosis membrane, NF membrane has height due to possessing under relatively low operating pressure
Water flux and high rejection advantage, therefore nanofiltration is widely used in valuable feed separation, wastewater treatment, drinks
The fields such as Water warfare.
PEI（Polyetherimide, PEI, Ultem1000）It is a kind of aromatic thermoplastic of function admirable
The presence of ether assigns its polymer chain considerable flexibility in polymeric material, structure.This material has been widely used for
In the membrane separating process such as pervaporation and gas separation.Also it is reported that PEI is one that anisotropic membrane is prepared with phase inversion
Suitable material is planted, and is applied in aqueous phase.
Graphene is a kind of two dimensional crystal material tightly packed by carbon atom, excellent because it has unique structure
The performances such as different electricity, mechanics, optics, chemistry and calorifics turn into the focus that many people study.And the oxidation with layer structure
Graphene is characterised by the hydroxyl on surface, carboxyl and epoxy-functional.GO has very strong mechanical strength, special heat
Performance, the excellent specific property such as high surface area ratio.Due to its two-dimentional hierarchy, oxygen-containing functional group and high surface area and extensive life
Required low cost can make it in water process and wastewater treatment as outstanding adsorbent during production functionalization GO.Therefore,
Graphene oxide is considered the appropriate component that polymer and inorganic particle are combined.
Polyethylene glycol can be as pore former, if carried out with polyethylene glycol to graphene oxide in the forming process of film
It is modified to prepare modified graphene oxide, it is used to prepare new PEI NF membrane as additive.So, it is sharp
Increase the porosity of polyetherimde films with the nanometer porous structure of modified graphene oxide, with big in effectively catching solution
Size solute molecule simultaneously increases the fluid duct for being conducive to solvent to pass through in film, realizes that the permeation flux and rejection of NF membrane are same
Shi Tigao.
The content of the invention
It is an object of the invention to provide a kind of preparation of the novel polyetherimide NF membrane containing modified graphene oxide
Method, by adding finely dispersed PEG-GO in preparation liquid, utilizes its nanometer porous structural improvement polyetherimde films
Pore structure, the fluid bore that solvent is passed through is conducive to the large scale solute molecule in effectively catching organic solution and increasing in film
Road, improves the selective performance of NF membrane.
In order to achieve the above object, the invention provides a kind of preparation method based on the PEG-GO NF membranes being modified, its
Comprise the following steps：
1）PEG-GO synthesis
By a certain amount of graphene oxide（GO）Add in deionized water and add a certain amount of poly- second two after ultrasonic a period of time
Alcohol（PEG）, stir the mixture for being freeze-dried after a period of time, finally give modified novel oxidized graphene（PEG-
GO）；
2）The preparation of preparation liquid
Under normal temperature, PEI high polymer material is dried in baking oven constant temperature stirring in organic solvent is dissolved in after certain time
Certain density organic phase solution is configured to being completely dissolved, the PEG-GO of synthesis is scattered in polyetherimide according to a certain percentage
Amine organic phase solution, is well mixed it, stands overnight to remove the bubble in preparation liquid；
3）PEG-GO Modified Membranes
The mixing preparation liquid stood is equably poured on dry, clean, smooth substrate, certain thickness is spread to doctor
Wet film and substrate, are together put into the min of coagulation bath 15, turn through abundant phase by the wet film of degree after stop certain time in atmosphere
Change obtains primary membrane.Gained primary membrane is soaked in deionized water again dries certain time in atmosphere after 24 h, after drying
Primary membrane post-processed with chemical crosslink technique, finally give the PEI NF membrane containing modified graphene oxide.
As preferred：
The step 1）In, ultrasonic time is 2 ~ 5 min, and polyethylene glycol used in the synthesis of modified graphene oxide is polyethylene glycol
200 ~ 2000 one kind, graphene oxide and polyethylene glycol addition mass ratio be：1:10~1:30.
The step 1）In, mixture mixing speed is 100 ~ 800 r/min, and mixing time is 12 ~ 24 h, freeze-drying
Temperature is -20 to -100 DEG C, and cooling time is 24 ~ 48 h.
The step 2）In, PEI drying time is 2 ~ 12 h, and the concentration of polyphenyl sulfolane solution is 5 ~ 35 wt%.
The step 2）In, organic solvent is 1-METHYLPYRROLIDONE（NMP）, DMF（DMF）And N,
N- dimethyl acetamides（DMAc）One kind；The adding proportion for adding the organic phase solution of modified graphene oxide is 0.05 ~ 2.0
wt%。
The step 3）In, the residence time is 0 ~ 5 min to wet film in atmosphere, and coagulation bath is ethanol, the one of deionized water
Plant or mixture；Wet-film thickness is 150 ~ 300 μm, and drying time is 12 ~ 24 h.
The step 3）In, the crosslinked fluid for being crosslinked primary membrane is 1,6- hexamethylene diamines, one kind of ethylenediamine, crosslinking time
For 12 ~ 24 h.
Beneficial effect：
Reticulated porous structures based on PEG-GO, its fill the inorganic salts that polyetherimde films can be in the effectively catching aqueous solution or its
Its solute molecule.With reference to PEG-GO and the advantage of polyetherimde films, new PEG-GO filling polyetherimides prepared by the present invention
The dye molecule that amine film is used in nanofiltration water separating membrane solution, can show high selectivity and high flux.The film work of the present invention
Skill is simple, the separating property lifting of made PEG-GO fillings polyetherimde films, the separative efficiency of nanofiltration can be improved, with very big
Development potentiality.
Embodiment
The present invention provides a kind of PEG-GO for nanofiltration separation aqueous dye solutions and fills polyetherimde films and its preparation
Method.Synthesize PEG-GO first, then PEG400, PEG1500, PEG-GO added into the system of PEI by a certain percentage respectively
It is post-treated to obtain the composite membrane in film liquid.
Synthesis：0.05 g GO are dissolved in ultrasonic 5 min in 2 mL deionized waters and obtain GO solution, and 1.0 g PEG400 are added
Enter GO solution；Under normal temperature, mixed solution is obtained into new PEG400-GO with the 300 r/min h of speed magnetic agitation 24 and disperseed
Liquid, the h of freeze-drying PEG400-GO dispersion liquids 24 can obtain powdered PEG400-GO under -50 °C.
Synthesis：The PEG1500-GO same PEG400-GO of synthetic method.
Separating property is evaluated and tested：PEG-GO filling PEI water separating membranes are determined using Flat Membrane performance evaluating apparatus molten
The nanofiltration separation performance of liquid system：Feed concentration is the 20 ppm Congo red aqueous solution, 25 °C of operation temperature, nanofiltration operation pressure difference
For 1.2 MPa；
The permeation flux and rejection of the evaluation of nanofiltration separation performance, i.e. film；
1）Permeation flux（J）, permeability of the membrane is reacted, its definition is：J = M / (A · t) orJ = V / (A · t)
In formula,MWithV distinguishesTo penetrate the penetrating fluid quality of film（kg）And volume（m3）；AFor membrane area, m2；tDuring for operation
Between, h；
2）Rejection（R）, the selectivity of reaction film, its definition is：R = (C f – C p ) / C f × 100%
In formula,C f WithC p Respectively concentration of the solute component in feed liquid and penetrating fluid.
Comparative example
Polyetherimde films：Under normal temperature, by PEI（PEI）High polymer material is dissolved in N, N- after drying 4 h in baking oven
Dimethyl acetamide（DMAc）Middle constant temperature is stirred to the preparation liquid for being completely dissolved into 22 wt%, and overnight stand is to remove in preparation liquid
Bubble.The PEI preparation liquids stood are equably poured on dry, clean, smooth stainless-steel sheet, with straight, light
Sliding and two ends are tied with the glass bar of adhesive tape and spread in certain thickness film, air is put into deionized water after stagnant empty 30 s
In, after its film forming and after coming off from steel plate after 15 min, then film is put into deionized water soaks 24 h and remained in removing
Solvent in film, obtains PEI nanofiltration primary membrane after spontaneously drying in atmosphere, and primary membrane is soaked in isopropanol
Steep 1 h, after by film transfer into crosslinked fluid 15 h, then be immersed in 1 h in isopropanol, most at last film in regulation liquid overnight
After take out, polyetherimde films are dried to obtain in atmosphere.
Embodiment 1 ~ 2
PEG-GO adds NF membrane：Appropriate PEG400-GO and PEG1500-GO is weighed respectively adds in DMAc ultrasonic disperse extremely
Uniformly, it is that 1.0 wt% are added in PEI preparation liquid by addition by PEG-GO dispersion liquids, phase is used for after stirring
Conversion method prepares the polyetherimde films of PEG-GO modifications.Other film preparation steps are identical with comparative example 1.Separating property is shown in Table 1,
PEG400-GO and PEG1500-GO addition can realize that polyetherimde films are same to the flux and rejection of the Congo red aqueous solution
Shi Tigao.
The separating property of the PEG-GO modified polyetherimide films of table 1
Claims (7)
1. a kind of preparation of the novel polyetherimide NF membrane containing modified graphene oxide, preparation method comprises the following steps：
The synthesis of modified graphene oxide, by a certain amount of graphene oxide（GO）Add in deionized water after ultrasonic a period of time
Add a certain amount of polyethylene glycol（PEG）, stir the mixture for being freeze-dried after a period of time, finally give modified
Novel oxidized graphene（PEG-GO）；
The preparation of preparation liquid, by PEI（PEI）Be dissolved in constant temperature in organic solvent stir to be completely dissolved be configured to it is certain
The PEI solution of concentration, PEI solution is scattered in by the novel oxidized graphene of synthesis according to a certain percentage, is made through ultrasound and stirring
Graphene oxide is uniformly dispersed, and gained preparation liquid stands overnight to remove bubble；
PEG-GO Modified Membranes, the mixing preparation liquid stood is equably poured on dry, clean, smooth substrate, with scraping
Ink knife spreads to certain thickness wet film, is in atmosphere together put into wet film and substrate in coagulation bath after stop certain time,
Primary membrane is obtained through abundant inversion of phases, gained primary membrane is dried after soaking in deionized water again, dried primary membrane is used
Chemical crosslink technique is post-processed, and finally gives the PEI NF membrane containing modified graphene oxide.
2. the synthesis of modified graphene oxide according to claim 1, it is characterised in that：Ultrasonic time is 2 ~ 5 min, modified
Polyethylene glycol used in the synthesis of graphene oxide is one kind of polyethylene glycol 200 ~ 2000, graphene oxide and polyethylene glycol addition
Mass ratio be：1:10~1:30.
3. the synthesis of modified graphene oxide according to claim 1, it is characterised in that：Mixture mixing speed be 100 ~
800 r/min, mixing time is 12 ~ 24 h, and freeze-drying temperature is -20 to -100 DEG C, and cooling time is 24 ~ 48 h.
4. the configuration of preparation liquid according to claim 1, it is characterised in that：The concentration of PEI solution is 5 ~ 35 wt%, You Jirong
Agent is 1-METHYLPYRROLIDONE（NMP）, DMF（DMF）And DMAC N,N' dimethyl acetamide（DMAc）One kind.
5. the preparation method of the PEI NF membrane according to claim 1 containing modified graphene oxide, its feature
It is：The adding proportion for adding the PEI solution of modified graphene oxide is 0.05 ~ 2.0 wt%, and coagulation bath is ethanol, deionization
One kind or mixture of water.
6. the preparation method of the PEI NF membrane according to claim 1 containing modified graphene oxide, its feature
It is：Wet-film thickness is 150 ~ 300 μm, and the residence time is 0 ~ 5 min to wet film in atmosphere, and drying time is 12 ~ 24 h.
7. the preparation method of the PEI NF membrane according to claim 1 containing modified graphene oxide, its feature
It is：Crosslinked fluid for being crosslinked primary membrane is 1,6- hexamethylene diamines, and one kind of ethylenediamine, crosslinking time is 12 ~ 24 h.
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Cited By (4)
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| CN108676461A (en) * | 2018-05-04 | 2018-10-19 | 砺剑防务技术集团有限公司 | Poly- silicon ceramic high-temperature resistant anticorrosive paint and preparation method thereof |
| CN111073500A (en) * | 2019-12-16 | 2020-04-28 | 苏州普希环保科技有限公司 | Film and method for producing same |
| CN112755821A (en) * | 2020-12-15 | 2021-05-07 | 上海应用技术大学 | PMIA mixed matrix ultrafiltration membrane with high flux and anti-pollution performance and preparation application thereof |
| CN112791697A (en) * | 2020-12-16 | 2021-05-14 | 华南理工大学 | Elastic super-hydrophobic graphene gel sphere and preparation method and application thereof |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108676461A (en) * | 2018-05-04 | 2018-10-19 | 砺剑防务技术集团有限公司 | Poly- silicon ceramic high-temperature resistant anticorrosive paint and preparation method thereof |
| CN111073500A (en) * | 2019-12-16 | 2020-04-28 | 苏州普希环保科技有限公司 | Film and method for producing same |
| CN112755821A (en) * | 2020-12-15 | 2021-05-07 | 上海应用技术大学 | PMIA mixed matrix ultrafiltration membrane with high flux and anti-pollution performance and preparation application thereof |
| CN112791697A (en) * | 2020-12-16 | 2021-05-14 | 华南理工大学 | Elastic super-hydrophobic graphene gel sphere and preparation method and application thereof |
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