CN114471157A - Preparation method of positively charged acid-resistant nanofiltration membrane and positively charged acid-resistant nanofiltration membrane - Google Patents
Preparation method of positively charged acid-resistant nanofiltration membrane and positively charged acid-resistant nanofiltration membrane Download PDFInfo
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- 239000012528 membrane Substances 0.000 title claims abstract description 157
- 239000002253 acid Substances 0.000 title claims abstract description 92
- 238000001728 nano-filtration Methods 0.000 title claims abstract description 70
- 238000002360 preparation method Methods 0.000 title claims abstract description 19
- 229920002492 poly(sulfone) Polymers 0.000 claims abstract description 54
- 238000000108 ultra-filtration Methods 0.000 claims abstract description 54
- 239000000243 solution Substances 0.000 claims abstract description 33
- 238000000034 method Methods 0.000 claims abstract description 21
- 229920000768 polyamine Polymers 0.000 claims abstract description 20
- 239000002904 solvent Substances 0.000 claims abstract description 20
- 239000007864 aqueous solution Substances 0.000 claims abstract description 17
- YBBRCQOCSYXUOC-UHFFFAOYSA-N sulfuryl dichloride Chemical compound ClS(Cl)(=O)=O YBBRCQOCSYXUOC-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229920002873 Polyethylenimine Polymers 0.000 claims abstract description 15
- 238000010438 heat treatment Methods 0.000 claims abstract description 10
- 238000003618 dip coating Methods 0.000 claims abstract description 9
- 239000011248 coating agent Substances 0.000 claims abstract description 8
- 238000000576 coating method Methods 0.000 claims abstract description 8
- 238000001035 drying Methods 0.000 claims abstract description 8
- 238000004140 cleaning Methods 0.000 claims abstract description 7
- 238000011033 desalting Methods 0.000 claims description 26
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 18
- 239000002250 absorbent Substances 0.000 claims description 16
- 230000002745 absorbent Effects 0.000 claims description 16
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 12
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 claims description 12
- IMNFDUFMRHMDMM-UHFFFAOYSA-N anhydrous n-heptane Natural products CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 claims description 10
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 8
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 claims description 8
- ZBJSGOMTEOPTBH-UHFFFAOYSA-N naphthalene-1,3,6-trisulfonyl chloride Chemical compound ClS(=O)(=O)C1=CC(S(Cl)(=O)=O)=CC2=CC(S(=O)(=O)Cl)=CC=C21 ZBJSGOMTEOPTBH-UHFFFAOYSA-N 0.000 claims description 6
- 239000004745 nonwoven fabric Substances 0.000 claims description 6
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 claims description 5
- 150000001335 aliphatic alkanes Chemical class 0.000 claims description 5
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 4
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 claims description 2
- 239000000835 fiber Substances 0.000 claims description 2
- 229920000728 polyester Polymers 0.000 claims description 2
- 239000012071 phase Substances 0.000 abstract description 40
- 229910021645 metal ion Inorganic materials 0.000 abstract description 17
- 239000008346 aqueous phase Substances 0.000 abstract description 10
- 238000000746 purification Methods 0.000 abstract description 5
- 238000002834 transmittance Methods 0.000 abstract description 2
- 238000010612 desalination reaction Methods 0.000 abstract 1
- 210000004379 membrane Anatomy 0.000 description 60
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 18
- 238000004132 cross linking Methods 0.000 description 10
- 239000000178 monomer Substances 0.000 description 10
- 238000000926 separation method Methods 0.000 description 7
- 238000012695 Interfacial polymerization Methods 0.000 description 6
- 150000003839 salts Chemical class 0.000 description 6
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- 125000003277 amino group Chemical group 0.000 description 4
- 238000006116 polymerization reaction Methods 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 3
- 239000005977 Ethylene Substances 0.000 description 3
- 239000004952 Polyamide Substances 0.000 description 3
- 230000002378 acidificating effect Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 230000004907 flux Effects 0.000 description 3
- 229920002647 polyamide Polymers 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 description 2
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 2
- GLUUGHFHXGJENI-UHFFFAOYSA-N Piperazine Chemical compound C1CNCCN1 GLUUGHFHXGJENI-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 150000001412 amines Chemical class 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012216 screening Methods 0.000 description 2
- 125000000542 sulfonic acid group Chemical group 0.000 description 2
- FZZMTSNZRBFGGU-UHFFFAOYSA-N 2-chloro-7-fluoroquinazolin-4-amine Chemical compound FC1=CC=C2C(N)=NC(Cl)=NC2=C1 FZZMTSNZRBFGGU-UHFFFAOYSA-N 0.000 description 1
- LEEDMQGKBNGPDN-UHFFFAOYSA-N 2-methylnonadecane Chemical compound CCCCCCCCCCCCCCCCCC(C)C LEEDMQGKBNGPDN-UHFFFAOYSA-N 0.000 description 1
- GNFTZDOKVXKIBK-UHFFFAOYSA-N 3-(2-methoxyethoxy)benzohydrazide Chemical compound COCCOC1=CC=CC(C(=O)NN)=C1 GNFTZDOKVXKIBK-UHFFFAOYSA-N 0.000 description 1
- 229910001200 Ferrotitanium Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 150000001263 acyl chlorides Chemical class 0.000 description 1
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 210000002469 basement membrane Anatomy 0.000 description 1
- 239000012267 brine Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000009295 crossflow filtration Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000010406 interfacial reaction Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- -1 iron ions Chemical class 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 1
- 235000019341 magnesium sulphate Nutrition 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- HPALAKNZSZLMCH-UHFFFAOYSA-M sodium;chloride;hydrate Chemical compound O.[Na+].[Cl-] HPALAKNZSZLMCH-UHFFFAOYSA-M 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 125000000472 sulfonyl group Chemical group *S(*)(=O)=O 0.000 description 1
- 239000012085 test solution Substances 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- 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
-
- 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
- B01D67/0088—Physical treatment with compounds, e.g. swelling, coating or impregnation
-
- 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
- B01D67/0095—Drying
-
- 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
- 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
- B01D2325/00—Details relating to properties of membranes
- B01D2325/26—Electrical properties
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Nanotechnology (AREA)
- Water Supply & Treatment (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention relates to a preparation method of a positively charged acid-resistant nanofiltration membrane and the positively charged acid-resistant nanofiltration membrane, the method comprises the steps of dip-coating polyamine aqueous solution on the surface of a polysulfone ultrafiltration base membrane, and removing redundant aqueous phase solution on the surface of the polysulfone ultrafiltration base membrane after standing for a preset first time period; dip-coating an oil phase solution containing polybasic sulfonyl chloride on the surface of the polysulfone ultrafiltration basal membrane, standing for a predetermined second time period, putting the polysulfone ultrafiltration basal membrane into an oven, and heating at 60-90 ℃; cleaning the membrane surface of the heated polysulfone ultrafiltration basal membrane by using the oil phase solvent, and removing the redundant oil phase solvent on the surface of the polysulfone ultrafiltration basal membrane; and (3) coating a polyethyleneimine solution on the polysulfone ultrafiltration base membrane, putting the polysulfone ultrafiltration base membrane into the oven again, and drying the polysulfone ultrafiltration base membrane at the temperature of 80-100 ℃ to obtain an acid-resistant nanofiltration membrane with positive charges on the surface, wherein the desalination layer has a sandwich structure. The positively charged acid-resistant nanofiltration membrane has excellent acid resistance, high acid transmittance and greatly improved metal ion removal rate, and is very suitable for the purification of dilute acid.
Description
Technical Field
The invention relates to the technical field of polymer separation membranes, and particularly relates to a preparation method of a positively charged acid-resistant nanofiltration membrane and the positively charged acid-resistant nanofiltration membrane.
Background
Nanofiltration is the most concerned membrane separation technology in recent years, and can realize efficient and energy-saving liquid separation. The aperture of the nanofiltration membrane is in a nanometer range, so that higher permeation flux can be obtained under lower operation pressure, monovalent and divalent metal ions can be separated, and meanwhile, the organic matters can be precisely screened in a certain molecular weight range, so that the nanofiltration membrane has wide application potential. The main application fields of nanofiltration include dye separation, drug concentration, water softening, organic matter removal and salt separation, nanofiltration has different interception mechanisms for different substances, interception is realized mainly by means of aperture screening of a separation layer for organic matters without charges, and comprehensive effects of aperture screening and charge effects are adopted for organic matters and ions with charges.
The desalting layer of the existing commercial nanofiltration membrane is polyamide formed by interfacial polymerization reaction of polyamine and polybasic acyl chloride, and amide bonds in the polyamide are easy to hydrolyze under acidic or alkaline conditions, so the commercial nanofiltration membrane has short service life under acidic or alkaline conditions, and cannot treat acidic or alkaline wastewater.
At present, the prior art discloses a polysulfonamide nanofiltration membrane prepared by polymerizing polyamine and polybasic sulfonyl chloride, and a polysulfonamide desalting layer has better acid resistance. CN 102120149A discloses a preparation method of an acid-resistant nanofiltration membrane, which adopts an interfacial polymerization method to prepare polysulfonamide on a porous substrate by interfacial polymerization with piperazine as a water-phase monomer and 1,3, 6-naphthalene trisulfonyl chloride as an oil-phase monomer. CN 103260731A discloses a preparation method of a polysulfonamide membrane, wherein an aqueous phase monomer is aliphatic ammonia, and an oil phase monomer is a compound containing sulfonyl groups.
In the prior art, the polysulfonamide nanofiltration membranes are prepared by interfacial polymerization between polyamine and polybasic sulfonyl chloride. The reaction speed between the polybasic ammonia and the polybasic sulfonyl chloride is slow, a loose nascent-state polysulfonamide desalting layer is formed firstly through interfacial reaction, a large number of sulfonyl chloride groups are remained in the nascent-state desalting layer, particularly the side close to an oil phase solvent in interfacial polymerization, and the sulfonyl chloride is finally hydrolyzed to generate sulfonic acid groups with negative electricity. Due to the loose desalting layer with a cross-linked structure and a negative electric desalting layer, the rejection rate of the membrane to metal ions is reduced under the attraction action of polyvalent metal ions and sulfonic acid groups on the desalting layer. For the reason, the acid-resistant nanofiltration membrane has low removal rate of metal ions in the waste acid, so that the application of the acid-resistant nanofiltration membrane is influenced, particularly the resource utilization of the waste acid is influenced, and no commercial polysulfonamide nanofiltration membrane sold on a large scale is available on the market.
In the production of titanium dioxide and steel rolling, a large amount of dilute acid containing high-concentration iron ions is generated, the dilute acid cannot be used after the concentration of metal ions in the dilute acid is accumulated to a certain degree, and the dilute acid needs to be treated. The traditional method adopts a neutralization method for treatment, generates a large amount of high-concentration brine and needs further treatment, and the treatment cost is extremely high. The acid-resistant nanofiltration membrane which has higher removal rate on metal ions with more than two valences and high transmittance on acid is adopted to physically separate the acid, so that the acid-resistant nanofiltration membrane is the best choice for treating the dilute acid, the metal ions can be removed by the acid-resistant nanofiltration membrane at lower operating pressure to realize the purification of the acid, the acid can be recycled, the use and disposal cost of the acid is greatly reduced, and the method is a green treatment technology. With the increasing attention of our country to environmental protection, the resource treatment of waste acid generated in the industrial production process becomes an urgent need, so that the development of an acid-resistant nanofiltration membrane with ultrahigh acid and metal ion separation rate, which can be industrialized, is imperative.
Disclosure of Invention
Therefore, the embodiment of the invention provides a preparation method of a positively charged acid-resistant nanofiltration membrane and the positively charged acid-resistant nanofiltration membrane, and solves the problems that the desalting layer of the acid-resistant nanofiltration membrane is low in crosslinking degree, the surface of the acid-resistant nanofiltration membrane is negatively charged and the removal rate of metal ions is low.
In order to achieve the above object, the embodiments of the present invention provide the following technical solutions: a preparation method of a positively charged acid-resistant nanofiltration membrane comprises the following steps:
(1) dip-coating polyamine aqueous solution on the surface of the polysulfone ultrafiltration basal membrane, standing for a preset first time period, and removing the redundant aqueous solution on the surface of the polysulfone ultrafiltration basal membrane;
(2) dip-coating an oil phase solution containing multi-element sulfonyl chloride on the membrane surface of the polysulfone ultrafiltration basal membrane, standing for a preset second time period, putting the polysulfone ultrafiltration basal membrane into an oven, and heating at 60-90 ℃;
(3) cleaning the membrane surface of the heated polysulfone ultrafiltration basal membrane by using an oil phase solvent, and removing the redundant oil phase solvent on the surface of the polysulfone ultrafiltration basal membrane;
(4) and coating a polyethyleneimine solution on the membrane surface of the polysulfone ultrafiltration membrane, putting the membrane into the oven again, and drying at 80-100 ℃ to obtain the acid-resistant nanofiltration membrane with the surface being positively charged.
As a preferred scheme of the preparation method of the positively charged acid-resistant nanofiltration membrane, the polysulfone ultrafiltration base membrane is a polysulfone flat ultrafiltration membrane taking polyester fiber non-woven fabric or PP non-woven fabric as a supporting layer.
As a preferable scheme of the preparation method of the positively charged acid-resistant nanofiltration membrane, in the step (1), the polyamine adopted in the polyamine aqueous solution is one or a mixture of more of ethylenediamine, diethyltriamine, triethyltetramine, tetraethylpentamine and polyethyleneimine, and the concentration of the polyamine is 0.5-4 wt%.
As a preferred scheme of the preparation method of the positively charged acid-resistant nanofiltration membrane, in the step (1), the polyamine aqueous solution contains an acid absorbent, the acid absorbent is one or more of sodium hydroxide, potassium hydroxide, sodium carbonate and triethylamine, and the concentration of the acid absorbent is 0.01-1% by weight.
As a preferred scheme of the preparation method of the positively charged acid-resistant nanofiltration membrane, in the step (1), standing is carried out for a predetermined first time period of 1-10 min, and after standing, an air knife or a rubber roller is adopted to remove redundant aqueous solution.
As a preferable scheme of the preparation method of the positively charged acid-resistant nanofiltration membrane, in the step (2), the polybasic sulfonyl chloride in the oil phase solution is 1,3, 6-naphthalene trisulfonyl chloride, and the concentration of the 1,3, 6-naphthalene trisulfonyl chloride in the oil phase solution is 0.1-1% by weight;
in the step (2), the solvent of the oil phase solution is ISOPAR G, cyclohexane, normal hexane, heptane or 12 alkane;
in the step (2), standing for a preset second time period of 1-5 min;
and (2) heating in an oven at 60-90 ℃ for 2-6 min, and controlling the air quantity to prevent the membrane surface oil phase solution of the polysulfone ultrafiltration membrane from being dried.
As a preferred scheme of the preparation method of the positively charged acid-resistant nanofiltration membrane, in the step (3), the adopted oil phase solvent is ISOPAR G, cyclohexane, n-hexane, heptane or 12 alkane;
in the step (3), after cleaning, redundant oil phase solvent droplets are removed by using an air knife or a rubber roller.
As a preferred scheme of the preparation method of the positively charged acid-resistant nanofiltration membrane, in the step (4), the membrane is placed in the oven again for drying for 2-6 min; the concentration of the used polyethyleneimine is 0.1 wt% -4 wt%;
as a preferable scheme of the preparation method of the positively charged acid-resistant nanofiltration membrane, in the step (4), the aqueous solution of polyethyleneimine contains an acid absorbent, wherein the acid absorbent is one or more of sodium hydroxide, potassium hydroxide, sodium carbonate and triethylamine, and the concentration of the acid absorbent is 0.01-1% by weight.
The invention also provides a positively charged acid-resistant nanofiltration membrane which is prepared by adopting the preparation method of the positively charged acid-resistant nanofiltration membrane and is provided with a desalting layer with a sandwich structure on the surface.
The method comprises the steps of dip-coating polyamine aqueous solution on the surface of a polysulfone ultrafiltration basal membrane, standing for a preset first time period, and removing the redundant aqueous solution on the surface of the polysulfone ultrafiltration basal membrane; dip-coating an oil phase solution containing polybasic sulfonyl chloride on the surface of the polysulfone ultrafiltration basal membrane, standing for a predetermined second time period, putting the polysulfone ultrafiltration basal membrane into an oven, and heating at 60-90 ℃; cleaning the membrane surface of the heated polysulfone ultrafiltration basal membrane by using the oil phase solvent, and removing the redundant oil phase solvent on the surface of the polysulfone ultrafiltration basal membrane; and (3) coating a polyethyleneimine solution on the polysulfone ultrafiltration base membrane, putting the polysulfone ultrafiltration base membrane into the oven again, and drying the polysulfone ultrafiltration base membrane at the temperature of 80-100 ℃ to obtain the acid-resistant nanofiltration membrane with positive charges on the surface. According to the invention, the surface of the primary desalting layer is coated with the aqueous phase solution, and the interface polymerization reaction is carried out again, so that the residual sulfonyl chloride group on the surface of the primary desalting layer is further consumed, the sulfonyl chloride group is prevented from being hydrolyzed into sulfonic acid, and the crosslinking degree of the desalting layer is increased; because part of amine groups on water phase molecules participate in the crosslinking reaction, the residual amine groups can lead the surface of the membrane to be positively charged, and the phenomenon of positive charge is particularly obvious because the water phase monomer adopts polyethyleneimine, thereby greatly improving the removal of metal ions; the method overcomes the defects of low surface cross-linking density and negative surface charge of the polysulfonamide nanofiltration membrane prepared by the traditional interface polymerization method, low final metal ion removal rate and low final acid purification efficiency.
Detailed Description
The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.
The embodiment of the invention provides a positively charged acid-resistant nanofiltration membrane, the surface of which is provided with a desalting layer with a sandwich structure.
Specifically, the positively charged acid-resistant nanofiltration membrane comprises: the device comprises a non-woven fabric supporting layer, a polysulfone ultrafiltration base membrane and a desalting layer with a sandwich structure. The polysulfone ultrafiltration basal membrane is connected with the non-woven fabric supporting layer; the desalting layer is connected with the polysulfone ultrafiltration basal membrane. In the invention, the polysulfone ultrafiltration basal membrane is coated in the order of water phase-oil phase-water phase, so that the upper surface and the lower surface of the desalting layer are respectively provided with positive charges and have a sandwich-like structure.
The residual sulfonyl chloride group on the surface of the primary polysulfonamide desalting layer reacts with the water-phase monomer coated on the surface of the desalting layer, so that the crosslinking density is further improved. The crosslinking density of the desalting layer is increased, and the positive charge of the surface gives higher metal ion removal rate to the acid-resistant nanofiltration membrane. The positively charged acid-resistant nanofiltration membrane overcomes the defects of low surface cross-linking density and negative surface charge of a polysulfonamide nanofiltration membrane prepared by the traditional interfacial polymerization method, low final metal ion removal rate and low final acid purification efficiency.
The preparation method of the positively charged acid-resistant nanofiltration membrane provided by the embodiment of the invention specifically comprises the following steps:
a) dissolving 0.5-4 wt% of polyamine and 0.01-1 wt% of acid absorbent in pure water to prepare a No. 1 aqueous phase solution, wherein the polyamine is preferably 3 ethylene 4 amine, 4 ethylene 5 amine or 5 ethylene 6 amine, and the acid absorbent is preferably sodium hydroxide;
b) preparing 0.1-1 wt% of 1,3, 6-naphthalene trisulfonyl chloride oil phase solvent into an oil phase solution, wherein the oil phase solvent can be ISOPAR G, cyclohexane, n-hexane, heptane or 12 alkane and liquid isoparaffin, preferably ISOPAR G;
c) dissolving 0.5-4 wt% of polyamine or polyethyleneimine concentration and 0.01-1 wt% of acid absorbent in pure water to prepare a No. 2 aqueous phase solution. The polyamine is preferably polyethyleneimine with the molecular weight of 5000-2000 daltons, and the acid absorbent is preferably sodium hydroxide;
d) coating the No. 1 aqueous phase solution on a polysulfone ultrafiltration basement membrane, standing for 1-10 min, and removing droplets on the membrane surface by using an air knife or a rubber roller after pouring the aqueous phase;
e) d, coating the oil phase solution on the polysulfone ultrafiltration base membrane coated with the water phase in the step d, standing for 1-5 min, and removing droplets on the membrane surface by using an air knife or a rubber roller after the oil phase is poured;
f) and e, transferring the membrane obtained in the step e into a drying oven with the temperature of 60-90 ℃ for heating for 2-6 minutes, controlling the air quantity to prevent the oil phase solution on the membrane surface from being dried, and promoting the water phase monomer and the oil phase monomer to react at a water-oil interface by heating to produce a primary desalting layer.
g) And taking the membrane out of the oven, washing the membrane surface with an oil phase solvent, removing residual oil phase monomers, and removing the redundant oil phase solution on the membrane surface with an air knife or a rubber roller.
h) And g, coating the 2# aqueous phase solution on the surface of the membrane obtained in the step g, standing for 1-10 min, pouring the aqueous phase solution, and removing droplets on the membrane surface by using an air knife or a rubber roller.
i) And (5) transferring the diaphragm obtained in the step h to an oven with the temperature of 80-100 ℃ for heating for 2-6 min, and controlling the air quantity to dry the diaphragm.
Therefore, the positively charged polyamide acid-resistant nanofiltration membrane with the sandwich-structure desalting layer can be prepared, the method is simple, the consumed time is short, the industrial continuous production is facilitated, and the obtained positively charged nanofiltration membrane is high in flux, high in metal ion removal rate and excellent in performance.
In order to test the performance of the composite desalting layer acid-resistant nanofiltration membrane, a 1% sulfuric acid solution is adopted to soak the membrane at 25 ℃ for 24 hours, and then the membrane is rinsed by pure water to be tested.
And (3) evaluating the performance of the positively charged polysulfonamide nanofiltration membrane: the membrane is evaluated in a cross-flow filtration mode, a 2000ppm magnesium sulfate solution is used as a test solution, the pH value is 7-8, and the water flux and the salt rejection rate of the membrane are tested under the pressure of 1.0 MPa.
Salt rejection rate R: salt concentration (C) in influent water under certain test conditionsf) With the salt concentration (C) in the produced waterp) The difference is divided by the salt concentration of the feed water:
water flux-the water yield per unit membrane area per unit time (L/m) under certain test conditions2.h)。
The following specific examples and test results:
in conclusion, the polyamine aqueous solution is dip-coated on the surface of the polysulfone ultrafiltration basal membrane, and after the polysulfone ultrafiltration basal membrane is kept still for a preset first time period, the redundant aqueous solution on the surface of the polysulfone ultrafiltration basal membrane is removed; dip-coating an oil phase solution containing polybasic sulfonyl chloride on the surface of the polysulfone ultrafiltration basal membrane, standing for a predetermined second time period, putting the polysulfone ultrafiltration basal membrane into an oven, and heating at 60-90 ℃; cleaning the membrane surface of the heated polysulfone ultrafiltration basal membrane by using the oil phase solvent, and removing the redundant oil phase solvent on the surface of the polysulfone ultrafiltration basal membrane; and (3) coating a polyethyleneimine solution on the polysulfone ultrafiltration base membrane, putting the polysulfone ultrafiltration base membrane into the oven again, and drying the polysulfone ultrafiltration base membrane at the temperature of 80-100 ℃ to obtain the acid-resistant nanofiltration membrane with positive charges on the surface. According to the invention, the surface of the primary desalting layer is coated with the aqueous phase solution, and the interface polymerization reaction is carried out again, so that the residual sulfonyl chloride group on the surface of the primary desalting layer is further consumed, the sulfonyl chloride group is prevented from being hydrolyzed into sulfonic acid, and the crosslinking degree of the desalting layer is increased; because part of amine groups on water phase molecules participate in the crosslinking reaction, the residual amine groups can lead the surface of the membrane to be positively charged, and the phenomenon of positive charge is particularly obvious because the water phase monomer adopts polyethyleneimine, thereby greatly improving the removal of metal ions; the method overcomes the defects of low surface cross-linking density and negative surface charge of the polysulfonamide nanofiltration membrane prepared by the traditional interface polymerization method, low final metal ion removal rate and low final acid purification efficiency.
Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (10)
1. The preparation method of the positively charged acid-resistant nanofiltration membrane is characterized by comprising the following steps of:
(1) dip-coating polyamine aqueous solution on the surface of the polysulfone ultrafiltration basal membrane, standing for a preset first time period, and removing the redundant aqueous solution on the surface of the polysulfone ultrafiltration basal membrane;
(2) dip-coating an oil phase solution containing multi-element sulfonyl chloride on the membrane surface of the polysulfone ultrafiltration basal membrane, standing for a preset second time period, putting the polysulfone ultrafiltration basal membrane into an oven, and heating at 60-90 ℃;
(3) cleaning the membrane surface of the heated polysulfone ultrafiltration basal membrane by using an oil phase solvent, and removing the redundant oil phase solvent on the surface of the polysulfone ultrafiltration basal membrane;
(4) and coating a polyethyleneimine solution on the membrane surface of the polysulfone ultrafiltration membrane, putting the membrane into the oven again, and drying at 80-100 ℃ to obtain the acid-resistant nanofiltration membrane with the surface being positively charged.
2. The method for preparing a positively charged acid-resistant nanofiltration membrane according to claim 1, wherein the polysulfone ultrafiltration membrane is a polysulfone flat ultrafiltration membrane using polyester fiber non-woven fabric or PP non-woven fabric as a support layer.
3. The method for preparing a positively charged acid resistant nanofiltration membrane according to claim 1, wherein in the step (1), the polyamine used in the polyamine aqueous solution is one or more of ethylenediamine, diethyltriamine, triethyltetramine, tetraethylpentamine and polyethyleneimine, and the concentration of the polyamine is 0.5-4 wt%.
4. The method for preparing a positively charged acid-resistant nanofiltration membrane according to claim 2, wherein in the step (1), the polyamine aqueous solution contains an acid absorbent, the acid absorbent is one or more of sodium hydroxide, potassium hydroxide, sodium carbonate and triethylamine, and the concentration of the acid absorbent is 0.01-1% by weight.
5. The method for preparing a positively charged acid-resistant nanofiltration membrane according to claim 1, wherein in the step (1), the membrane is kept still for a predetermined first time period of 1-10 min, and an air knife or a rubber roller is used for removing excess aqueous solution after the membrane is kept still.
6. The method for preparing a positively charged acid-resistant nanofiltration membrane according to claim 1, wherein in the step (2), the polybasic sulfonyl chloride in the oil phase solution is 1,3, 6-naphthalene trisulfonyl chloride, and the concentration of the 1,3, 6-naphthalene trisulfonyl chloride in the oil phase solution is 0.1-1% by weight;
in the step (2), the solvent of the oil phase solution is ISOPAR G, cyclohexane, normal hexane, heptane or 12 alkane;
in the step (2), standing for a preset second time period of 1-5 min;
and (2) heating in an oven at 60-90 ℃ for 2-6 min, and controlling the air quantity to prevent the membrane surface oil phase solution of the polysulfone ultrafiltration membrane from being dried.
7. The method for preparing the positively charged acid resistant nanofiltration membrane according to claim 1, wherein in the step (3), the oil phase solvent is ISOPAR G, cyclohexane, n-hexane, heptane or 12 alkane;
in the step (3), after cleaning, redundant oil phase solvent droplets are removed by using an air knife or a rubber roller.
8. The method for preparing the positively charged acid-resistant nanofiltration membrane according to claim 1, wherein in the step (4), the membrane is placed in the oven again for drying for 2-6 min; the concentration of the polyethyleneimine is 0.1 wt% to 4 wt%.
9. The method for preparing a positively charged acid-resistant nanofiltration membrane according to claim 8, wherein in the step (4), the aqueous solution of polyethyleneimine contains an acid absorbent, wherein the acid absorbent is one or more of sodium hydroxide, potassium hydroxide, sodium carbonate and triethylamine, and the concentration of the acid absorbent is 0.01-1% by weight.
10. A positively charged acid-resistant nanofiltration membrane prepared by the method for preparing a positively charged acid-resistant nanofiltration membrane according to any one of claims 1 to 9, wherein the surface of the positively charged acid-resistant nanofiltration membrane is provided with a desalting layer with a sandwich structure.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115043466A (en) * | 2022-08-10 | 2022-09-13 | 杭州水处理技术研究开发中心有限公司 | High-salt high-concentration organic wastewater treatment device |
| CN115364687A (en) * | 2022-08-18 | 2022-11-22 | 天津工业大学 | High-performance nanofiltration membrane and preparation method and application thereof |
| CN115608176A (en) * | 2022-11-11 | 2023-01-17 | 中国科学院赣江创新研究院 | Structure of high-performance polysulfonamide acid-resistant nanofiltration membrane and preparation method thereof |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102120149A (en) * | 2011-01-30 | 2011-07-13 | 杭州方然滤膜技术有限公司 | Method for preparing acid-proof polysulfonamide nanofiltration composite film |
| US20160009759A1 (en) * | 2013-02-26 | 2016-01-14 | Agency For Science, Technology And Research | Protein purification in the presence of nonionic organic polymers and electropositive surfaces |
| CN109200823A (en) * | 2018-08-28 | 2019-01-15 | 浙江工业大学 | A kind of preparation method and application for the ecosystem positively charged nanofiltration membranes that polyethyleneimine is amine-modified |
| CN109999665A (en) * | 2019-04-30 | 2019-07-12 | 中国科学院生态环境研究中心 | Lotus positive electricity anti-acid nanofiltration membrane, preparation method and application |
| CN111437736A (en) * | 2020-04-09 | 2020-07-24 | 浙江美易膜科技有限公司 | Organic composite membrane containing graphene oxide and preparation method thereof |
| CN112642305A (en) * | 2021-01-12 | 2021-04-13 | 天津工业大学 | Acid-resistant composite nanofiltration membrane and preparation method thereof |
| CN112717712A (en) * | 2020-12-15 | 2021-04-30 | 中国科学院过程工程研究所 | Acid-resistant nanofiltration membrane and preparation method and application thereof |
| CN112844046A (en) * | 2021-01-19 | 2021-05-28 | 恩泰环保科技（常州）有限公司 | Positively charged nanofiltration membrane and preparation method thereof |
| WO2021215484A1 (en) * | 2020-04-21 | 2021-10-28 | 東レ株式会社 | Method for recovering rare metal salt |
-
2022
- 2022-01-24 CN CN202210082294.1A patent/CN114471157A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102120149A (en) * | 2011-01-30 | 2011-07-13 | 杭州方然滤膜技术有限公司 | Method for preparing acid-proof polysulfonamide nanofiltration composite film |
| US20160009759A1 (en) * | 2013-02-26 | 2016-01-14 | Agency For Science, Technology And Research | Protein purification in the presence of nonionic organic polymers and electropositive surfaces |
| CN109200823A (en) * | 2018-08-28 | 2019-01-15 | 浙江工业大学 | A kind of preparation method and application for the ecosystem positively charged nanofiltration membranes that polyethyleneimine is amine-modified |
| CN109999665A (en) * | 2019-04-30 | 2019-07-12 | 中国科学院生态环境研究中心 | Lotus positive electricity anti-acid nanofiltration membrane, preparation method and application |
| CN111437736A (en) * | 2020-04-09 | 2020-07-24 | 浙江美易膜科技有限公司 | Organic composite membrane containing graphene oxide and preparation method thereof |
| WO2021215484A1 (en) * | 2020-04-21 | 2021-10-28 | 東レ株式会社 | Method for recovering rare metal salt |
| CN112717712A (en) * | 2020-12-15 | 2021-04-30 | 中国科学院过程工程研究所 | Acid-resistant nanofiltration membrane and preparation method and application thereof |
| CN112642305A (en) * | 2021-01-12 | 2021-04-13 | 天津工业大学 | Acid-resistant composite nanofiltration membrane and preparation method thereof |
| CN112844046A (en) * | 2021-01-19 | 2021-05-28 | 恩泰环保科技（常州）有限公司 | Positively charged nanofiltration membrane and preparation method thereof |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115043466A (en) * | 2022-08-10 | 2022-09-13 | 杭州水处理技术研究开发中心有限公司 | High-salt high-concentration organic wastewater treatment device |
| CN115043466B (en) * | 2022-08-10 | 2022-12-09 | 杭州水处理技术研究开发中心有限公司 | High-salt high-concentration organic wastewater treatment device |
| CN115364687A (en) * | 2022-08-18 | 2022-11-22 | 天津工业大学 | High-performance nanofiltration membrane and preparation method and application thereof |
| CN115608176A (en) * | 2022-11-11 | 2023-01-17 | 中国科学院赣江创新研究院 | Structure of high-performance polysulfonamide acid-resistant nanofiltration membrane and preparation method thereof |
| CN115608176B (en) * | 2022-11-11 | 2023-11-10 | 中国科学院赣江创新研究院 | Structure of high-performance polyamide acid-resistant nanofiltration membrane and preparation method thereof |
| CN115646212A (en) * | 2022-12-27 | 2023-01-31 | 湖南沁森高科新材料有限公司 | Nanofiltration membrane and preparation method thereof |
| CN115646212B (en) * | 2022-12-27 | 2023-03-10 | 湖南沁森高科新材料有限公司 | Nanofiltration membrane and preparation method thereof |
| 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 |
| CN118045493A (en) * | 2024-02-21 | 2024-05-17 | 中国石油大学(华东) | Acid-resistant composite membrane with high desalination performance |
| CN119236707A (en) * | 2024-12-05 | 2025-01-03 | 山东海化集团有限公司 | Preparation method of a high-pressure and high-salt concentration composite nanofiltration membrane and nanofiltration membrane thereof |
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