CN115463556A - Mixed matrix membrane based on dual-functional modified GO nanosheets and preparation method and application thereof - Google Patents

Mixed matrix membrane based on dual-functional modified GO nanosheets and preparation method and application thereof Download PDF

Info

Publication number
CN115463556A
CN115463556A CN202211059716.XA CN202211059716A CN115463556A CN 115463556 A CN115463556 A CN 115463556A CN 202211059716 A CN202211059716 A CN 202211059716A CN 115463556 A CN115463556 A CN 115463556A
Authority
CN
China
Prior art keywords
sgo
mixed matrix
pebax
membrane
nanosheets
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202211059716.XA
Other languages
Chinese (zh)
Inventor
郭瑞丽
朱伟芳
刘福
曹珩珩
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shihezi University
Original Assignee
Shihezi University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shihezi University filed Critical Shihezi University
Priority to CN202211059716.XA priority Critical patent/CN115463556A/en
Publication of CN115463556A publication Critical patent/CN115463556A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • B01D69/12—Composite membranes; Ultra-thin membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/22—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by diffusion
    • B01D53/228—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by diffusion characterised by specific membranes
    • 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
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/50—Carbon oxides
    • B01D2257/504—Carbon dioxide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2325/00—Details relating to properties of membranes
    • B01D2325/36—Hydrophilic membranes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
    • Y02C20/00—Capture or disposal of greenhouse gases
    • Y02C20/40—Capture or disposal of greenhouse gases of CO2

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

The invention belongs to the technical field of gas separation membranes, and particularly relates to a mixed matrix membrane based on dual-function modified GO nanosheets, and a preparation method and application thereof. The invention designs the method for efficiently separating CO by combining physical magnetic guidance and chemical functional modification 2 A novel membrane material of the molecule is a Pebax/FSGO mixed matrix membrane. Based on sulfonic acid hydrophilic modification and magnetic modification of graphene oxide nanosheets, the modified nanosheets and Pebax are physically blended and are directionally arranged under the induction of an external magnetic field. Realize to CO 2 The high-efficiency separation is realized. Hydrophilic modification of sulfonic acid groups not only endows GO nanosheets with stronger CO 2 Interaction site, and as a hydrophilic groupCan absorb and retain a large amount of water, form hydrophilic channels in the membrane, and increase CO 2 Adsorption and selectivity of (a). Induced to CO by an external magnetic field 2 The molecules provide a directional transmission path. The prepared Pebax/FSGO mixed matrix membrane has excellent gas separation performance and wide application prospect in the field of gas membrane separation.

Description

Mixed matrix membrane based on difunctional modified GO nanosheets and preparation method and application thereof
Technical Field
The invention belongs to the technical field of gas separation membranes, and particularly relates to a mixed matrix membrane based on dual-function modified GO nanosheets, and a preparation method and application thereof.
Background
The main component of biogas and biogas is methane (CH) 4 ) Belongs to green, environment-friendly and renewable energy sources. High purity biogas CH 4 The purity of the biogas is more than 98%, but a certain amount of carbon dioxide (CO) is usually accompanied in the initial biogas 2 ) A gas. Separating out the CO 2 The gas is important for the purification of biogas because of the CO content 2 The gas not only corrodes the gas pipeline, but also reduces the combustion heat value of the natural gas and reduces the quality of the gas. CO capture commonly used at present 2 The method includes adsorption, absorption, cryogenic separation, etc. However, these methods all have the characteristics of low energy consumption, environmental pollution and the like. The membrane separation method has the advantages of environmental protection, low energy consumption, low investment and the like, so that the method can be used for separating CO 2 The method is a modern high-tech technology and has good development prospect. Among them, the selection of highly efficient membrane materials is the core of membrane separation technology.
The membrane material can be classified into a polymer membrane, an inorganic membrane, and a polymer-inorganic hybrid membrane (mixed matrix membrane). The mixed matrix membrane has attracted wide attention due to the combination of the advantages of good film-forming property and easy modification of an organic membrane, high separation efficiency of an inorganic membrane, good mechanical property and the like, and can effectively overcome the 'trade-off' effect of a polymer membrane, namely the gas permeability and the selectivity of the membrane are in inverse proportion. The inorganic fillers of the mixed matrix membrane range from the original zeolites, metal oxide materials to novel porous materials (e.g., metal organic framework MOFs, covalent organic framework COFs, etc.). Researchers have incorporated these inorganic fillers into polymeric matrices to make mixed matrix membranes. Prior research advances have found that improvement in gas separation performance is limited by relying only on the unique structural characteristics of the inorganic filler itself. The development of inorganic fillers with synergistic functionality is important for the preparation of mixed matrix membranes with high separation performance.
Disclosure of Invention
In view of the above, the invention aims to provide a mixed matrix membrane based on bifunctional modified GO nanosheets, and a preparation method and application thereof. The provided mixed matrix membrane constructs a synergic gas transfer channel in the Pebax polymer matrix, and solves the problem of 'trade-off' effect of the Pebax membrane, namely the permeability and the selectivity of the membrane cannot be improved simultaneously.
In order to realize the purpose of the invention, the invention adopts the following technical scheme:
in a particular embodiment, the invention provides a mixed matrix membrane of bifunctional modified GO nanosheets, comprising Fe grown in situ on two-dimensional SGO nanosheets 3 O 4 Fe (b) of 3 O 4 -SGO nanosheets, with Fe 3 O 4 -SGO nanoplatelets as filler physically blended with polyether-polyamide copolymer (Pebax 1657).
Preferably, the filler comprises 1wt% to 5wt% of the total amount of the entire mixed matrix film. Fe in the mixed matrix film 3 O 4 -SGO nanoplates are in a vertical arrangement.
In a specific embodiment, the invention also provides a preparation method of the mixed matrix membrane of bifunctional modified GO nanosheets, the preparation method comprising the following steps:
(1) Carrying out sulfonic acid group hydrophilic modification on the two-dimensional flaky GO nano sheet to obtain an SGO nano sheet;
(2) FeCl 3 ·6H 2 O and FeCl 2 ·4H 2 Dissolving O in deionized water, and introducing N 2 Protection; adding the SGO nanosheet in the step (1), performing ultrasonic dispersion, and then heating and stirring; gradually adding ammonia water to adjust the pH value, continuously stirring, magnetically attracting and enriching the product, pouring out the supernatant, washing with deionized water until the supernatant is neutral and colorless, and drying in a vacuum drying oven to obtain Fe 3 O 4 -SGO nanoplatelets;
(3) Fe obtained in the step (2) 3 O 4 Physically blending the-SGO nanosheet and the Pebax solution, and stirring at room temperature to obtain a membrane casting solution;
(4) And (4) pouring the casting solution obtained in the step (3) on a clean plane, placing the casting solution in a magnetic field, naturally drying to form a film, and performing vacuum drying to obtain the mixed matrix film of the bifunctional modified GO nanosheets.
Further, the FeCl in the step (2) 3 ·6H 2 O and FeCl 2 ·4H 2 The dosage ratio of O and SGO nano sheets is as follows: 0.6995g:0.2573g: 80-120 mg.
The pH value in the step (2) is 9.5-10.
Fe in the casting solution in the step (3) 3 O 4 The content of the-SGO nanosheet is 1-5 wt%. Preferably, said Fe 3 O 4 The content of-SGO nanoplates was 3wt%.
The mass fraction of the Pebax in the Pebax solution in the step (3) is 4-6 wt%.
And (4) placing the magnetic field in the horizontal or vertical direction.
Preferably, the step (4) is performed by placing in a magnetic field perpendicular to the direction of the magnetic field.
The temperature of the vacuum drying in the step (4) is 40-50 ℃, and the time is 18-24 h.
Furthermore, the invention also provides the mixed matrix membrane prepared by the method in CO 2 Application in the field of separations.
Compared with the prior art, the invention has the following beneficial effects:
the invention designs the method for efficiently separating CO by combining physical magnetic guidance and chemical functional modification 2 A novel membrane material of the molecule is a Pebax/FSGO mixed matrix membrane. Based on sulfonic acid hydrophilic modification and magnetic modification of graphene oxide nanosheets, the obtained Fe 3 O 4 Physical blending is carried out on the-SGO nano sheet and the Pebax, and oriented arrangement is carried out under the induction of an external magnetic field, so that the defect of CO in the existing GO-based mixed matrix membrane is overcome 2 Low permeability, and can realize CO separation 2 The separation is efficient. Sulfonic acid group (-SO) 3 H) The hydrophilic modification not only endows GO nano-sheets with stronger CO 2 Interaction sites and the hydrophilic groups can absorb and retain a large amount of water, hydrophilic channels are constructed in the membrane, and CO is increased 2 Adsorption and selectivity of (a). Induced to CO by an external magnetic field 2 Molecules provide directional transportAnd (4) routing. The prepared Pebax/FSGO mixed matrix membrane has excellent gas separation performance and wide application prospect in the field of gas membrane separation.
Drawings
Fig. 1 is a scanning electron and transmission electron microscope image of GO and SGO nanoplates prepared;
FIG. 2 is Fe prepared 3 O 4 -EDS energy spectrum of SGO nanoplates;
FIG. 3 is a graph showing the comparison of gas separation performance under dry pure gas conditions of mixed matrix membranes of different filler types prepared;
FIG. 4 is a graph comparing gas separation performance under dry pure gas conditions of the prepared mixed matrix membrane with different magnetic field directions;
FIG. 5 is a graph comparing the gas separation performance under dry pure gas conditions for the prepared mixed matrix membranes with different filler contents and pure Pebax membranes;
FIG. 6 is a comparison of gas separation performance of the prepared mixed matrix membranes with different filler contents and pure Pebax membranes in a humidified state;
fig. 7 is a cross-sectional view of the prepared mixed matrix film under a scanning electron microscope.
Detailed Description
The invention will be further illustrated below, these examples being intended to illustrate the invention only and not to limit the scope of the invention; the experimental methods in the examples, which are not indicated for specific conditions, are carried out according to conventional conditions; the reagents and materials used, unless otherwise specified, are commercially available.
Example 1
In this example, mixed matrix membranes of different types of fillers were prepared, the filler content was 3wt%, and the specific preparation method included the following steps:
(1) 115mL of concentrated sulfuric acid (H) was weighed out 2 SO 4 ) Placing into ice water bath (temperature of 0 + -2 deg.C), stirring vigorously, adding 5g graphite powder and 2.5g sodium nitrate (NaNO) while stirring 3 ). Stirring was continued vigorously and 15g of potassium permanganate (KMnO) were added slowly in portions 4 ) And continuously stirring the mixture in an ice-water bath for 2 hours to ensure that the temperature of the solution is kept at about 0 ℃. Transferring the mixed solution into a constant-temperature water bath at 35 +/-LStirring was maintained at 2 ℃ for 30min. 230mL of deionized water was slowly added to the above solution, and the rate of addition of water was controlled so that the temperature of the system did not exceed 100 ℃. After the water is added, the temperature of the water bath is adjusted to 80 ℃, the temperature is kept constant for 3 hours, the reactant is poured into 1L of deionized water for dilution, and 30mL of 30 percent hydrogen peroxide (H) is added 2 O 2 ) And the product was washed well with 5% hydrochloric acid. And (3) centrifugally washing the graphene oxide nano sheet to be neutral by water, and then freezing and drying the graphene oxide nano sheet to obtain a Graphene Oxide (GO) nano sheet. And performing SEM and TEM characterization on the obtained GO nanosheet to determine the two-dimensional sheet structure of the GO nanosheet.
(2) 5mL of 2 percent sodium hydroxide (NaOH) solution and 0.5g of sulfanilic acid are stirred and dissolved in water bath, and the temperature of the water bath is 50-60 ℃ until the sulfanilic acid is fully dissolved. To the above solution was added 0.2g of sodium nitrite (NaNO) at room temperature 2 ) Until dissolved, 10mL of ice water and 1mL of concentrated hydrochloric acid (HCl) were added with stirring and the temperature was maintained at 0 ℃ for 15min. And (2) dropwise adding the obtained mixed solution into a flask containing 50mL of GO solution (10 mg/mL) prepared in the step (1), continuously stirring for 2-4 h under the condition of ice-water bath, and centrifugally washing and drying the solution with water to obtain Sulfonated Graphene Oxide (SGO). And performing SEM and TEM characterization on the obtained SGO nanosheet to determine the two-dimensional sheet structure of the SGO nanosheet. Fig. 1 is a scanning electron and transmission electron microscope image of GO and SGO nanoplates prepared; in the figure, (a), (b) are SEM images of GO nanosheets, and (c) is TEM image of GO nanosheets; (d) The SEM pictures of the SGO nano-sheets, and the TEM pictures of the SGO nano-sheets. As can be seen from FIG. 1, the prepared GO is a two-dimensional sheet material, the surface of the GO is relatively wrinkled, and the thickness of the GO is about 30-40 nm. SGOs also have a two-dimensional sheet structure, but are reduced in size compared to GO. GO and SGO after ultrasonic treatment are both in a sheet shape. Sulfonating the GO nanosheets did not change the structure of GO.
(3) 0.6995g of iron chloride hexahydrate (FeCl) 3 ·6H 2 O) with 0.2573g of ferrous chloride tetrahydrate (FeCl) 2 ·4H 2 O) was dissolved in 200mL of deionized water and N was added 2 Protection; 100mg of SGO obtained in the step (2) was added to the above solution, and after ultrasonic dispersion for 1 hour, the solution was stirred at 50 ℃ for 30min. Then 25wt% ofAmmonia water with the final pH value of 9.5-10, continuously stirring for 30min, enriching the product by a magnet, pouring out the supernatant, adding deionized water, washing until the supernatant is neutral and colorless, and drying in a vacuum drying oven at 70 ℃ for 12h to obtain Fe 3 O 4 -SGO nanoplates. Fe to be prepared 3 O 4 -SGO nanoplates for EDS characterization. FIG. 2 is Fe prepared 3 O 4 -EDS energy spectrum of SGO nanoplates; as can be seen from FIG. 2, fe and S elements are uniformly dispersed in Fe 3 O 4 Surface of SGO nanosheets, thus illustrating Fe 3 O 4 The magnetic modification of the nano particles and the hydrophilic modification of sulfonic acid groups are successful.
(4) Three portions of 0.5269g of polyether-polyamide block copolymer (Pebax) particles are weighed and dissolved in 15mL of absolute ethyl alcohol aqueous solution (the mass fraction ratio of absolute ethyl alcohol to water is 7.
(5) Respectively taking 0.01630g of GO nano-sheet, SGO nano-sheet and Fe with the same mass 3 O 4 Physically blending an-SGO nanosheet serving as a filler with the 4wt% Pebax high molecular solution prepared in the step (4), and stirring for 3 hours at room temperature to respectively obtain a Pebax/GO-3 membrane casting solution, a Pebax/SGO-3 membrane casting solution and a Pebax/Fe 3 O 4 -SGO-3 membrane casting solution; pouring each membrane casting solution on a clean culture dish, naturally drying for 48h at room temperature, removing the membrane, and vacuum drying for 24h in a vacuum drying oven at 40 ℃ to obtain Pebax/GO-3, pebax/SGO-3 and Pebax/Fe 3 O 4 -SGO-3 (Pebax/FSGO-3) mixed matrix membranes.
The pure gas separation performance of the prepared Pebax/GO-3, pebax/SGO-3 and Pebax/FSGO-3 mixed matrix membranes at 25 ℃ and 0.2MPa is tested by a gas permeameter. The permeability coefficient P (Barrer) of each mixed matrix membrane to each gas under the condition of dry pure gas is measured, and the gas selectivity alpha is obtained through the ratio of the permeability coefficients of the two gases. The test results show that the CO corresponding to Pebax/GO-3, pebax/SGO-3 and Pebax/FSGO-3 mixed matrix membranes 2 Permeability and CO 2 /CH 4 The selectivity is 47.76Barrer and 12.05, 48.51B respectivelyarrer and 12.13, 82.57Barrer and 16.74.
FIG. 3 is a graph comparing the gas separation performance under dry pure gas conditions for the mixed matrix membranes of different filler types prepared. As can be seen from FIG. 3, fe 3 O 4 The gas separation performance of the mixed matrix membrane of the SGO nanosheet is obviously higher than that of a Mixed Matrix Membrane (MMMs) taking GO and SGO as fillers, so that the gas separation performance is obviously improved after the GO is subjected to bifunctional modification. Compared with the GO modified with single function, the GO modified with sulfonic acid and magnetic modification has better separation performance, which shows that the physical and chemical double regulation is more effective than the single regulation. The obtained Pebax/FSGO-3 mixed matrix membrane has CO compared with the first two membranes 2 Higher permeability, CO 2 /CH 4 The selectivity is better.
Example 2
In the embodiment, the preparation method of the Pebax/FSGO-3 mixed matrix membrane in different magnetic field directions comprises the following steps:
pouring three parts of the Pebax/FSGO-3 casting solution prepared in the example 1 onto a clean culture dish, respectively placing the culture dish in the middle of a magnet in the horizontal magnetic field direction, in the middle of a magnet in the vertical magnetic field direction and in a non-magnetic field, naturally drying at room temperature for 48h, uncovering the membrane, and performing vacuum drying in a vacuum drying oven at 40 ℃ for 24h to obtain Pebax/Fe with different magnetic field orientations 3 O 4 -SGO-3 mixed matrix membrane. The films in the horizontal, vertical and non-magnetic field directions are respectively denoted as Pebax/FSGO-3 H 、Pebax/FSGO-3 V And Pebax/FSGO-3 R 。
The prepared Pebax/FSGO-3 is tested by the same method as the example 1 R 、Pebax/FSGO-3 H And Pebax/FSGO-3 V The mixed matrix membrane has pure gas separation performance under the conditions of 25 ℃ and 0.2 MPa. After testing, pbax/FeSGO-3 is obtained C 、Pebax/FSGO-3 H And Pebax/FSGO-3 V CO corresponding to mixed matrix membrane 2 Permeability and CO 2 /CH 4 The selectivities were 76.49Barrer and 15.51, 63.43Barrer and 18.92, 82.57Barrer and 16.74, respectively.
FIG. 4 shows the dry state of the prepared mixed matrix membrane with different magnetic field directionsAnd (3) a gas separation performance comparison diagram under the pure gas condition. It can be seen from FIG. 4 that different magnetic field guiding pairs Fe 3 O 4 The impact of the gas separation performance of the SGO-based mixed matrix membrane is different. The vertical magnetic field is more heavily influenced by gas permeability and the horizontal magnetic field is more heavily influenced by gas selectivity. Due to Fe in different magnetic field directions 3 O 4 The induced arrangement of the-SGO nanosheets in the polymer matrix is different, so that Fe 3 O 4 The role played by the-SGO nanoplates in the membrane is also inconsistent. When in a vertical magnetic field, fe 3 O 4 the-SGO nanosheets are vertically arranged, so that the diffusion path of gas molecules is greatly shortened in a high-molecular matrix, and the gas molecules can permeate the nano-sheets. While under a horizontal magnetic field, fe 3 O 4 the-SGO nano sheets are horizontally arranged, a gas transfer channel parallel to the membrane surface is constructed, and the difference of diffusion rates is caused by the difference of gas molecular dynamic diameters, so that the selectivity is favorably improved.
Example 3
This example examines the different contents (1 wt%, 3wt%, 5wt% and 7 wt%) of Fe in the direction of the perpendicular magnetic field 3 O 4 CO of Pebax/FSGO mixed matrix membranes prepared by SGO 2 Permeability and CO 2 /CH 4 And (4) selectivity performance. Meanwhile, pure Pebax films were used as reference for comparison.
0.0053g, 0.01630g, 0.0277g and 0.0396g of Fe prepared in example 1 were respectively taken 3 O 4 Physical blending is carried out on the SGO nanosheet and a Pebax solution with the concentration of 4wt%, stirring is carried out for 3 hours at room temperature to obtain Pebax/FSGO-1, pebax/FSGO-3, pebax/FSGO-5 and Pebax/FSGO-7 membrane casting solutions, the membrane casting solutions are respectively poured onto a clean culture dish, the culture dish is placed in a magnet in the direction of a vertical magnetic field, natural drying is carried out for 48 hours at room temperature, then, after membrane uncovering, vacuum drying is carried out in a vacuum drying oven with the temperature of 40 ℃ for 24 hours, and then the Pebax/FSGO mixed matrix membrane with different filler contents is obtained.
The prepared mixed matrix membrane Pebax/FSGO-1 is respectively tested by the same method as the embodiment 1 V 、Pebax/FSGO-3 V 、Pebax/FSGO-5 V And Pebax/FSGO-7 V Pure gas separation performance at 25 ℃ and 0.2 MPa. Through a processTesting to obtain a mixed matrix membrane Pebax/FSGO-1 V 、Pebax/FSGO-3 V 、Pebax/FSGO-5 V And Pebax/FSGO-7 V Corresponding CO 2 Permeability and CO 2 /CH 4 The selectivities were 57.17Barrer and 12.80, 82.57Barrer and 16.74, 76.44Barrer and 12.40, 59.01Barrer and 8.53, respectively. CO of pure Pebax membranes 2 Permeability and CO 2 /CH 4 The selectivities were 54.26Barrer and 9.71 respectively.
Fig. 5 is a graph comparing the gas separation performance under dry pure gas conditions for the prepared mixed matrix membranes with different filler contents and pure Pebax membranes. As can be seen from FIG. 5, as the filler content increases, the CO of the matrix film is mixed 2 Permeability and CO 2 /CH 4 The selectivity shows the trend of increasing first and then decreasing. When the content of the filler is 1 to 5 weight percent, the Pebax/FSGO-3 V Has better gas separation performance, and Pebax/FSGO-3 when the content of the filler is 3wt percent V The best gas separation performance is achieved. CO of the membrane at this time 2 Permeability and CO 2 /CH 4 The selectivity was improved by 52% and 72% respectively compared to pure Pebax membranes. However, when the content of the nanoplatelets exceeds 3wt%, the filler agglomerates, resulting in a Pebax/FSGO mixed matrix membrane CO 2 The separation performance is degraded. When the filler content reaches 7wt%, the selectivity of the membrane is lower than that of a pure membrane because the nanosheets are heavily agglomerated and interface defects occur.
Example 4
In this embodiment, the gas separation device is used to measure the permeability coefficient P of each mixed matrix membrane to each gas under the humidified mixed gas condition, and the gas selectivity α is obtained from the ratio of the permeability coefficients of the two gases. Measuring Pebax/FSGO-1 V 、Pebax/FSGO-3 V 、Pebax/FSGO-5 V And Pebax/FSGO-7 V CO corresponding to mixed matrix membrane 2 Permeability and CO 2 /CH 4 The selectivities were 378.75Barrer and 28.14, 564.63Barrer and 38.84, 448.12Barrer and 30.74, 332.35Barrer and 26.88, respectively. CO of pure Pebax membranes 2 Permeability and CO 2 /CH 4 The selectivities were 204.75Barrer and 28.71, respectively.
FIG. 6 shows different fillers withComparative gas separation performance of the mixed matrix membrane and pure Pebax membrane in a humidified state. As can be seen from fig. 6, the performance of the membrane in the humidified state is greatly improved. On the one hand, the polymer chains swell in water, facilitating the transfer of gas molecules. In addition, the water molecules themselves can accelerate CO 2 And (4) transferring molecules. Results of gas separation Performance indicate Fe 3 O 4 -SGO nanosheet has a hydrophilic sulfonic acid group and a metal oxide group, both of which may be CO 2 The molecule provides a large number of affinity sites for CO 2 Infiltration and selection of.
The Pebax/FSGO mixed matrix membrane can be obviously seen in CO in a wet state 2 The permeability and the selectivity are improved compared with the pure membrane. CO 2 2 Permeability and CO 2 /CH 4 The selectivity was increased by 52% and 72% respectively compared to pure Pebax membranes. Shows that the Pebax/FSGO mixed matrix membrane provided by the invention is applied to CO 2 Has excellent separation performance in permeation and selection.
FIG. 7 is a sectional view of each of the mixed matrix films prepared by scanning electron microscopy; as can be seen in FIG. 7, the Pebax/GO membranes contain-SO in comparison 3 The H-modified SGO nanosheet and the polymer matrix have better compatibility, the section of the Pebax/SGO membrane becomes smoother, and the wrinkles are obviously reduced. In addition, compared with Pebax/SGO, the filler is subjected to oriented arrangement under different magnetic fields after magnetic modification. In the absence of magnetic field, the prepared Pebax/Fe 3 O 4 -SGO-3 R Are arranged in disorder in the membrane. Under the horizontal magnetic field, the prepared Pebax/Fe 3 O 4 -SGO-3 H Tending to align horizontally within the membrane. Under the vertical magnetic field, the prepared Pebax/Fe 3 O 4 -SGO-3 V Tending to align vertically within the film. This indicates that Fe can be effectively controlled by magnetic field steering 3 O 4 -arrangement of SGO nanoplates within the membrane.
Example 5
0.6995g of FeCl 3 ·6H 2 O with 0.2573g FeCl 2 ·4H 2 O was dissolved in 300mL of deionized water and N was added 2 Protection; adding 120mg SGO into the solution, dispersing for 1.2h with ultrasound, dissolvingStirring the solution at 60 deg.C for 20min; then dropwise adding 25wt% of ammonia water, keeping the final pH value at 9.5, continuously stirring for 20min, enriching the product by a magnet, pouring out the supernatant, adding deionized water, washing until the supernatant is neutral and colorless, and drying in a vacuum drying oven at 60 ℃ for 15h to obtain Fe 3 O 4 -SGO nanoplates.
0.01630g of Fe is taken 3 O 4 Physically blending an SGO nanosheet serving as a filler with 6wt% of Pebax high polymer solution, and stirring at room temperature for 4 hours to obtain a membrane casting solution; and pouring the membrane casting solution on a clean utensil, putting the utensil in the middle of a magnet perpendicular to the magnetic field direction, naturally drying for 36 hours at room temperature, and after removing the membrane, drying in a vacuum drying oven at 45 ℃ for 20 hours to obtain the Pebax/FSGO mixed matrix membrane.
Example 6
0.6995g of FeCl 3 ·6H 2 O with 0.2573g FeCl 2 ·4H 2 O was dissolved in 180mL of deionized water and N was added 2 Protection; adding 80mg of SGO into the solution, performing ultrasonic dispersion for 1.5h, and stirring the solution at 50 ℃ for 20min; then dropwise adding 25wt% ammonia water, keeping the pH value at 10, continuously stirring for 30min, enriching the product by a magnet, pouring out the supernatant, adding deionized water, washing until the supernatant is neutral and colorless, and drying in a vacuum drying oven at 80 ℃ for 10h to obtain the Fe 3 O 4 -SGO nanoplates.
0.01630g of Fe is taken 3 O 4 Physically blending an SGO nanosheet serving as a filler with 5wt% of Pebax high molecular solution, and stirring at room temperature for 5 hours to obtain a membrane casting solution; and pouring the casting solution on a clean vessel, putting the vessel in the middle of a magnet in the horizontal magnetic field direction, naturally drying for 42h at room temperature, and after removing the membrane, drying in a vacuum drying oven at 50 ℃ for 18h in vacuum to obtain the Pebax/FSGO mixed matrix membrane.
The invention designs the method for efficiently separating CO by combining physical magnetic guidance and chemical functional modification 2 The novel molecular membrane material constructs a synergic transfer channel in a high-molecular matrix, and has wide application prospect in the field of gas membrane separation.
While embodiments of the invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the invention, and that various embodiments or examples and features of various embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Claims (10)

1. A mixed matrix membrane of dual-functional modified GO nano-sheets is characterized in that the mixed matrix membrane contains Fe grown in situ on two-dimensional SGO nano-sheets 3 O 4 Fe (b) of 3 O 4 -SGO nanoplatelets in Fe 3 O 4 -SGO nanoplatelets as filler physically blended with polyether-polyamide copolymer.
2. The mixed matrix membrane according to claim 1, wherein the filler accounts for 1 to 5wt% of the total amount of the mixed matrix membrane. Fe in the mixed matrix film 3 O 4 -SGO nanoplates are in a vertical arrangement.
3. A preparation method of a mixed matrix membrane of difunctional modified GO nanosheets is characterized by comprising the following steps:
(1) Carrying out sulfonic acid group hydrophilic modification on a two-dimensional flaky GO nanosheet to obtain an SGO nanosheet;
(2) FeCl is added 3 ·6H 2 O and FeCl 2 ·4H 2 Dissolving O in deionized water, and introducing N 2 Protection; adding the SGO nanosheet in the step (1), performing ultrasonic dispersion, and then heating and stirring; gradually adding ammonia water to adjust the pH value, continuously stirring, magnetically attracting and enriching the product, pouring out the supernatant, washing with deionized water until the supernatant is neutral and colorless, and drying in a vacuum drying oven to obtain Fe 3 O 4 -SGO nanoplates;
(3) Fe obtained in the step (2) 3 O 4 Physically blending the SGO nanosheet and the Pebax solution, and stirring at room temperature to obtain a membrane casting solution;
(4) And (4) pouring the casting solution obtained in the step (3) on a clean plane, placing the casting solution in a magnetic field, naturally drying the casting solution to form a film, and performing vacuum drying to obtain the mixed matrix film of the bifunctional modified GO nanosheets.
4. The method according to claim 3, wherein the FeCl is prepared in the step (2) 3 ·6H 2 O and FeCl 2 ·4H 2 The dosage ratio of O and SGO nano sheets is as follows: 0.6995g:0.2573g: 80-120 mg.
5. The method according to claim 3, wherein the pH in the step (2) is 9.5 to 10.
6. The production method according to claim 3, wherein Fe in the casting solution in step (3) 3 O 4 The content of the-SGO nanosheet is 1 to 5wt%.
7. The method according to claim 3, wherein the mass fraction of Pebax in the Pebax solution in step (3) is 4 to 6wt%.
8. The method according to claim 3, wherein the step (4) is performed in a manner that the magnetic field is horizontally or vertically disposed.
9. The method according to claim 3, wherein the temperature of the vacuum drying in the step (4) is 40 to 50 ℃ and the time is 18 to 24 hours.
10. The mixed matrix membrane of claim 1 in CO 2 Application in the field of separations.
CN202211059716.XA 2022-08-30 2022-08-30 Mixed matrix membrane based on dual-functional modified GO nanosheets and preparation method and application thereof Pending CN115463556A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211059716.XA CN115463556A (en) 2022-08-30 2022-08-30 Mixed matrix membrane based on dual-functional modified GO nanosheets and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211059716.XA CN115463556A (en) 2022-08-30 2022-08-30 Mixed matrix membrane based on dual-functional modified GO nanosheets and preparation method and application thereof

Publications (1)

Publication Number Publication Date
CN115463556A true CN115463556A (en) 2022-12-13

Family

ID=84368696

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211059716.XA Pending CN115463556A (en) 2022-08-30 2022-08-30 Mixed matrix membrane based on dual-functional modified GO nanosheets and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN115463556A (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3709841A (en) * 1969-04-30 1973-01-09 Rhone Poulenc Sa Sulfonated polyarylethersulfones
CN104028125A (en) * 2014-06-27 2014-09-10 天津大学 Double-functional graphene oxide filled hybrid membrane as well as preparation method and application thereof
CN105478078A (en) * 2015-11-25 2016-04-13 蚌埠学院 Preparation method and use of highly dispersed magnetic graphene nanometer adsorbent
US20170087519A1 (en) * 2014-03-17 2017-03-30 Washington University Composite nanostructures having a crumpled graphene oxide shell
CN107281941A (en) * 2017-06-23 2017-10-24 江南大学 A kind of magnetic graphene mixed substrate membrane containing nano-grade molecular sieve and preparation method thereof
CN111266019A (en) * 2020-01-23 2020-06-12 天津大学 Preparation method and application of vertically-oriented magnetic nanosheet/sodium alginate composite membrane
CN113318604A (en) * 2021-06-29 2021-08-31 中海油天津化工研究设计院有限公司 Preparation method of sulfonated graphene oxide/polymer mixed matrix membrane for gas separation

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3709841A (en) * 1969-04-30 1973-01-09 Rhone Poulenc Sa Sulfonated polyarylethersulfones
US20170087519A1 (en) * 2014-03-17 2017-03-30 Washington University Composite nanostructures having a crumpled graphene oxide shell
CN104028125A (en) * 2014-06-27 2014-09-10 天津大学 Double-functional graphene oxide filled hybrid membrane as well as preparation method and application thereof
CN105478078A (en) * 2015-11-25 2016-04-13 蚌埠学院 Preparation method and use of highly dispersed magnetic graphene nanometer adsorbent
CN107281941A (en) * 2017-06-23 2017-10-24 江南大学 A kind of magnetic graphene mixed substrate membrane containing nano-grade molecular sieve and preparation method thereof
CN111266019A (en) * 2020-01-23 2020-06-12 天津大学 Preparation method and application of vertically-oriented magnetic nanosheet/sodium alginate composite membrane
CN113318604A (en) * 2021-06-29 2021-08-31 中海油天津化工研究设计院有限公司 Preparation method of sulfonated graphene oxide/polymer mixed matrix membrane for gas separation

Similar Documents

Publication Publication Date Title
Chen et al. PIM-based mixed-matrix membranes containing MOF-801/ionic liquid nanocomposites for enhanced CO2 separation performance
Lin et al. Gradiently distributed iron oxide@ graphene oxide nanofillers in quaternized polyvinyl alcohol composite to enhance alkaline fuel cell power density
Yun et al. Crosslinked sulfonated poly (vinyl alcohol)/sulfonated multi-walled carbon nanotubes nanocomposite membranes for direct methanol fuel cells
Wang et al. Anti-bacterial and super-hydrophilic bamboo charcoal with amidoxime modified for efficient and selective uranium extraction from seawater
CN104779400B (en) A kind of preparation method of the modified carbon nano-tube for PEM
Zhu et al. Introducing hydrophilic ultra-thin ZIF-L into mixed matrix membranes for CO 2/CH 4 separation
CN106750440A (en) ZIF@CNT modified polymer hybrid PEM and preparation method thereof
Kumar et al. Synergistic role of graphene oxide-magnetite nanofillers contribution on ionic conductivity and permeability for polybenzimidazole membrane electrolytes
CN105390721B (en) A kind of preparation method of boron phosphate enveloped carbon nanometer tube compound proton exchange membrane
Zhu et al. Mixed matrix membrane containing metal oxide nanosheets for efficient CO2 separation
Zheng et al. 3D hollow CoNi-LDH nanocages based MMMs with low resistance and CO2-philic transport channel to boost CO2 capture
Pazani et al. Engineered graphene-based mixed matrix membranes to boost CO2 separation performance: Latest developments and future prospects
Ni et al. LDH nanosheets anchored on bacterial cellulose-based composite anion exchange membranes for significantly enhanced strength and ionic conductivity
Bavasso et al. Sulfonated Fe3O4/PES nanocomposites as efficient separators in microbial fuel cells
CN111617645A (en) Preparation method of low-resistance high-selectivity mixed matrix membrane based on hollow MOFs (metal-organic frameworks) material
Zhao et al. Fabricating Leaf-like hierarchical ZIF-67 as Intra-Mixed matrix membrane microarchitecture for efficient intensification of CO2 separation
CN113506904B (en) Proton exchange membrane and preparation method and application thereof
CN108744991B (en) Preparation method and application of organic-inorganic mixed matrix membrane doped with zeolite imidazole ester framework porous carbon nano material
CN115463556A (en) Mixed matrix membrane based on dual-functional modified GO nanosheets and preparation method and application thereof
Luo et al. From 0D to 3D nanomaterial-based composite membranes for CO2 capture: Recent advances and perspectives
Qian et al. High-performance ZIF-302 mixed-matrix membranes for efficient CO2 capture
CN113828170A (en) Mixed matrix membrane and preparation method and application thereof
CN103641101A (en) Two-dimensional structural carbon nanomaterial and preparation method thereof
Liu et al. Mixed‐matrix membranes based on Li1. 6Mn1. 6O4 (LMO) ultrathin nanosheet for high‐performance CO2 separation
CN115888632A (en) Silica aerogel solid-liquid composite CO 2 Adsorbent, preparation method and application

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination