CN108159891A - A kind of N- sulfenamides based polyamide water softens loose reverse osmosis composite membrane and preparation method thereof - Google Patents

A kind of N- sulfenamides based polyamide water softens loose reverse osmosis composite membrane and preparation method thereof Download PDF

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CN108159891A
CN108159891A CN201810024861.1A CN201810024861A CN108159891A CN 108159891 A CN108159891 A CN 108159891A CN 201810024861 A CN201810024861 A CN 201810024861A CN 108159891 A CN108159891 A CN 108159891A
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composite membrane
reverse osmosis
amine
water
preparation
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牛青山
胡平
郭鑫
徐泽文
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China University of Petroleum East China
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0002—Organic membrane manufacture
    • B01D67/0006—Organic membrane manufacture by chemical reactions
    • 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
    • B01D69/10—Supported membranes; Membrane supports
    • 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
    • B01D69/125—In situ manufacturing by polymerisation, polycondensation, cross-linking or chemical reaction
    • 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
    • B01D71/56—Polyamides, e.g. polyester-amides
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C02F1/441—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by reverse osmosis
    • 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
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A20/00—Water conservation; Efficient water supply; Efficient water use
    • Y02A20/124—Water desalination
    • Y02A20/131—Reverse-osmosis

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

The invention discloses a kind of loose reverse osmosis composite membranes of N sulfenamides based polyamide and preparation method thereof, belong to macromolecule member material technical field.The composite membrane is on porous support membrane, it is formed by the monomer by the structure of sulfenamide containing N or polymer with Primary Fatty race amine monomers through interfacial polymerization, its surface lotus has low electronegativity or electroneutral, and surface roughness is low, therefore is shown in performance to divalent and polyvalent cation with excellent rejection effect and good resistance tocrocking.In addition, the composite membrane of the preparation is not only good to conventional water softening effect, but also to being rich in SO4 2‑High-salt wastewater still have good water softening power.Therefore, the water treatment fields such as water softening, the separation of dyestuff/salt, sea water desalination and bitter pretreatment be can be widely used in.

Description

A kind of N- sulfenamides based polyamide water softens loose reverse osmosis composite membrane and its preparation Method
Technical field
The present invention relates to membrane for water treatment field of material technology, and in particular to a kind of N- sulfonamidos for water softening are new Loose reverse osmosis composite membrane of type polyamide and preparation method thereof.
Background technology
Hard water refers to the water containing more solubility calcium magnesium compound, mainly including tap water, underground well water, spring, hardship Salt water, seawater and boiler feed water etc..Drink population up to 38,000,000 people of bitter in China, high-content calcium-magnesium ratio in drinking water The health of the mankind can be threatened by closing the presence of object.In the industry calcium salt, magnesium salts precipitation can cause bird nest, interfere heat transfer, Industrially every year because the tens million of members of cost are wanted in equipment, the repair of pipeline and replacement.The concentrated seawater generated in desalting process because Rich in calcium ions and magnesium ions, the bottleneck of concentrated seawater batch production salt making technology restrict.Therefore the development of water softening is extremely urgent, especially exists Soften the fields such as drinking water, seawater desalinization pretreatment, middle low-pressure boiler water and recirculated water make-up water.Industrial conventional softening Method is soda ash method and ion-exchange.The former reagent is cheap but limited to the removal ability of hardness ions, and effluent quality It is not easy to control；And the latter needs frequent regeneration, consumes a large amount of regenerative agents, and generates a large amount of regenerated environmental pollution by water.Embrane method water Softening process have need not regeneration, it is pollution-free generate, go completely oil removal and organic matter, effluent quality it is excellent, it is easy to operate, account for The advantages that ground area is few has significant Social benefit and economic benefit.
At present, the water softening composite membrane used in embrane method water softening process is mostly commercialized polyamide composite nanofiltration membrane, They pass through the 1,3,5- pyromellitic trimethylsilyl chlorides monomer (TMC) of oil phase and the piperazine monomer (PIP) or m-phenylene diamine (MPD) of water phase mostly Monomer (MPD) interfacial polymerization is prepared.For PIP-TMC polyamide nanofiltration membranes, due to the water of acid chloride groups in oil phase monomer Solution forms carboxyl and so that the composite film surface bear prepared is electrical.And in practical water softening process, according to the road of NF membrane Southern effect, the electronegative characteristic of surface lotus are unfavorable for Ca in hard water2+/Mg2+Removal.In addition, the active carboxylic acid of composite film surface Group easily with Ca in hard water2+Form calcium bridge, enhance the active force of organic pollutant and film surface, so cause fouling membrane and Membrane separating property declines.And for the loose reverse osmosis composite membrane of MPD-TMC polyamide, because it is dissolved by MPD-flooding mechanism controlled System, the film surface roughness of preparation is very big, and antifouling property is poor.
Therefore, the preparation of high-performance water softening composite membrane becomes the research hotspot of water treatment field in recent decades.Mainly Be divided into two class strategies, one kind be regulate and control the lotus electropositive of composite film surface with according to charged repelling effect improve divalent metal sun from The retention of son, the methods of such as utilizing the monomer doping with polyamine group, surface graft modification, be graft-polymerized.In these researchs Mainly simply mono-salt (CaCl2/MgCl2) rejection or mixed salt (with Cl-As coexisting ion) in (Ca2+/Mg2+)/ (Na+) the index selectively as evaluating combined film water softening power, however there are a large amount of divalent the moon in practical hard water Ion such as SO4 2-, content is up to 2500ppm (seawater) from 100ppm (surface water).When handling high-salt wastewater, these divalent are cloudy Ion can be by electrostatic interaction and the positive charge of film surface can even cause transformation or the electron screening of film surface charge Effect also can seriously weaken the electrostatic repulsion ability of charged film surface.Another kind of is layer by layer from group using crosslinked polyelectrolyte The aperture size of dress method regulation and control composite membrane and distribution are to retain all bivalent cations, but polyelectrolyte self assembly layer by layer Technique is cumbersome, poor by electrostatic force combination membrane stability.Therefore, the new water phase and an oil phase monomer with specific structure is prepared, is changed Become the membrane formation mechanism of interfacial polymerization, the composite membrane of preparation is allow to cooperate with aperture screening and road south repelling effect, is contained in retention During high mixed salt solution, excellent Ca can be embodied2+、Mg2+Rejection, meanwhile, low surface is presented in the composite film surface of preparation Roughness has excellent stain resistance, is the new approaches for preparing high-performance antipollution water softening composite membrane.Thus the present invention with It is starting point to research and develop high performance composite membrane new material, develops new monomer, regulates and controls the charge and pore-size distribution of composite film surface, Antipollution high-performance water is prepared by interfacial polymerization techniques and appropriate aftertreatment technology and softens composite membrane.
Invention content
The purpose of the present invention is to provide a kind of loose reverse osmosis composite membrane of N- sulfenamides based polyamide and its preparation sides Method softens composite membrane film because causing Ca during film surface negatively charged to solve existing water2+/Mg2+Wait divalent metals retention Rate it is relatively low and because film surface roughness greatly caused by anti-fouling performance it is poor the problem of.
The technical solution that the present invention solves above-mentioned technical problem is as follows：
A kind of preparation method of the loose reverse osmosis composite membrane of N- sulfenamides based polyamide, including：
(1) will through ultrafiltration supporting layer pretreatment under conditions of normal pressure, room temperature, relative humidity are not higher than 70% in water 60-300s is impregnated in phase amine monomers aqueous solution, forms water phase liquid layer；Wherein, water phase amine monomers be primary aliphatic amine monomers, water A concentration of 0.5-2.0wt% of phase amine monomers；
(2) the water phase liquid layer with the organic solvent solution containing organic phase activated monomer is in contact, is gathered by interface It closes reaction and generates aramid layer in ultrafiltration support layer surface, the interfacial polymerization time is 10s-300s, and N- sulfonamidos are made and gather The loose reverse osmosis composite membrane of amide；
Wherein, organic phase activated monomer is the fragrance at least one amido protecting group and at least two acid chloride groups Race or alicyclic organic matter, protected amino be N- sulfonamidos, a concentration of 0.005- of organic phase activated monomer 0.3wt%.
The present invention regulates and controls the charge and pore-size distribution of composite film surface, passes through interface by preparing new oil phase monomer Polymerization technique and appropriate aftertreatment technology prepare antipollution high-performance water softening composite membrane.Prepared by the present invention has specific structure New oil phase monomer, change the membrane formation mechanism in interfacial polymerization process, the composite membrane of preparation can cooperate with aperture to sieve and road Southern effect contains there are many during zwitterion mixed solution in retention, can embody excellent Ca2+、Mg2+Rejection, meanwhile, system Low surface roughness is presented in standby composite film surface, has excellent stain resistance.
Specifically, the loose reverse osmosis composite membrane of N- sulfenamide based polyamides of the invention by N- sulfonamidos monomer with Primary Fatty race amine monomers are generated through interface polymerization reaction.On the one hand, after being hydrolyzed because of the acyl chlorides monomer of the group containing amido protecting Structure is：
Monomer structure after being hydrolyzed with 1,3,5- pyromellitic trimethylsilyl chlorides monomer (TMC)：
It compares, formation-NH after being deprotected because of N- sulfuryl amine groups2Influence, in structure-PKa of COOH group Larger, the ability of acid protonation is weak.On the other hand, N- sulfenamides group acts on forming-NH through deprotection2, reduce film The quantity of surface-active-COOH group.Therefore, it can be changed after the acyl chlorides monomer of the sulfuryl amine group containing N- is reacted with amine monomers compound The charged negativity of film surface, according to road south repelling effect, the composite membrane containing this class formation has excellent Ca2+With Mg2+It is contour Valency cation rejection.
The composite membrane of the present invention is mainly by N- sulfonamidos monomer and primary aliphatic amine monomers through interface polymerization reaction Generation both can be mixed into oil phase monomer solution and all kinds of water phase level-one fat by N- sulfonamidos monomer and TMC monomer molecules Fat amine monomers solution reaction also can individually be reacted by N- sulfonamidos monomer molecule with Primary Fatty race amine monomers, such Reaction can be carried out by interfacial polymerization, can also be carried out by LBL self-assembly (solvent method or spin-coating method) mode, can also be passed through gas Phase depositional mode carries out, and the film thickness that the present invention generates on porous ultrafiltration supporting layer has excellent between 20-200nm Divalent metal rejection and good stain resistance.
Further, in preferred embodiments of the present invention, above-mentioned preparation method further includes：(3) it is obtained to step (2) Product is post-processed, and post-processing step includes：The product is handled into 2-10min at 50-90 DEG C, then with n-hexane, One or more combinations in pure water and water phase additive aqueous solution are cleaned.
Further, in preferred embodiments of the present invention, in step (1), the ultrafiltration supporting layer is located in advance Reason the specific steps are：Ultrafiltration supporting layer with isopropanol and deionized water is cleaned successively, then removes surface with air knife Extra water layer；After the ultrafiltration supporting layer is impregnated in water phase amine monomers aqueous solution, purged with air knife, remove surface excess Water phase amine monomers aqueous solution.
Further, in preferred embodiments of the present invention, above-mentioned primary aliphatic monomer is d-glucosamine, hyperbranched poly Aziridine, 1,4- cyclohexanediamine, 1,2- cyclohexanediamine, 1,3- cyclohexanediamine, three (2- amino-ethyls) amine, three (2- amino first Base) amine, three (2- aminopropyls) amine, N, N- bis- (amino-ethyl) ethylenediamine, ethylenediamine, 1,3- propane diamine, diethylenetriamines, One kind in trien and 1,4- butanediamine.It is highly preferred that primary aliphatic monomer is hyperbranched polyethyleneimine, 1, 4 cyclohexanediamine, three (2- amino-ethyls) amine, ethylenediamine, 1,3 propane diamine or diethylenetriamine.
Wherein, the molecular structure of hyperbranched polyethyleneimine：
The molecular structure of 1,4 cyclohexanediamine is：
The molecular structure of three (2- amino-ethyls) amine is：
The molecular structure of ethylenediamine is：
The molecular structure of 1,3 propane diamine is：
The molecular structure of diethylenetriamine is：
Further, in preferred embodiments of the present invention, above-mentioned organic phase activated monomer is (the N- sulfenamides of 1,3- bis- Base) two N- sulfenamides of equal benzoyl chloride, 5- (N- sulfonamidos) m-phthaloyl chlorides or 1,3- isophthalic.
Wherein, the molecular structural formula of 1,3- bis- (N- sulfonamidos) benzoyl chlorides is：
The molecular structural formula of 5- (N- sulfonamidos) m-phthaloyl chloride is：
The molecular structural formula of two N- sulfenamides of 1,3- isophthalic is：
Further, in preferred embodiments of the present invention, in step (1), the water phase additive that uses for organic sulfonic acid, One or more combinations in organic amine, alcohol, organophosphor, dimethyl sulfoxide (DMSO), acetone and quaternary ammonium salt.
Further, in preferred embodiments of the present invention, in step (2), the organic solvent used is n-hexane, hexamethylene One or more combinations in alkane, normal heptane, toluene, benzene and isoparaffin organic solvent.
Further, in preferred embodiments of the present invention, above-mentioned ultrafiltration supporting layer by polysulfones, polyether sulfone, polyimides, One or more in the derivative of Kynoar and polyacrylonitrile and these polymer are prepared.It is it is highly preferred that super Filter supporting layer is prepared by polysulfones and/or polyether sulfone.
The loose reverse osmosis composite membrane of N- sulfenamide based polyamides that above-mentioned preparation method is prepared.
Further, in preferred embodiments of the present invention, the thickness of above-mentioned N- sulfonamidos polyamide composite film is 20-200nm.The N- sulfonamido polyamide composite film surface roughnesses are low, the low electronegativity of surface lotus or electroneutral.
The invention has the advantages that：
The present invention using the monomer of sulfonamido containing N- mixing TMC monomers or the monomer molecule of sulfonamido containing N- with it is all kinds of Primary Fatty race amine monomers reaction generation polyamide composite film film, thickness have relatively low surface roughness in 20-200nm, Preferable antifouling property.
Due to the deprotection effect generation-NH of N- sulfenamide groups2The product reacted with amine monomers has high pKa Value, film surface elecrtonegativity reduce so that the loose reverse osmosis membrane of polyamide of preparation embodies divalent and polyvalent cation excellent Rejection.
Structure of composite membrane prepared by the present invention is comparatively dense, right according to aperture screening with the repulsion of road south by influencing In high concentration SO4 2-The water softening power of hard water with high salt existing for ion is still fine.It can be widely used in Ca2+、Mg2+Etc. divalent The water softening process of cation removing, such as household water filter, sea water desalination and bitter pretreatment field.
Specific embodiment
The principle of the present invention and feature are described with reference to embodiments, the given examples are served only to explain the present invention, It is not intended to limit the scope of the present invention.The person that is not specified actual conditions in embodiment suggests according to normal condition or manufacturer Condition carries out.Reagents or instruments used without specified manufacturer is the conventional products that can be obtained by commercially available purchase.For Facilitate description, in the statement of following embodiment, composite membrane to the permeant flux unit LMH of feedstock solution be rise/square metre/it is small When.In test pressure 1.0MPa, 25 DEG C of system temperature control, the test of the cross-flow method of operation, raw water flow control under conditions of 7LPM After precompressed 2h, the prepared loose reverse osmosis composite membrane of polyamide is tested to 2000ppm MgSO4、2000ppm CaCl2And The salt rejection rate and flux of 2000ppm NaCl.Mixed salt is tested, 13500ppm mixed salts are carried out under test pressure 1.5MPa Test (mixed salt stoste composition such as table 1).Rejection (R) of the present invention is defined as：Under certain condition, feeding liquid concentration (Cf) with oozing Concentration difference (C in transparent liquidp), then divided by feeding liquid concentration R=(Cf-Cp)/Cf.Salt-mixture intermediate ion concentration of the present invention by from Sub- chromatography detection.
The preparation condition of the embodiment of the present invention is：Normal pressure, room temperature, relative humidity are not higher than 70%.
Embodiment 1：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, aqueous phase solution, 5- are done with Isosorbide-5-Nitrae-cyclohexanediamine aqueous solution The hexamethylene toluene mixed solution of (N- sulfenamides) m-phthaloyl chloride does organic phase solution, and polyamides is prepared by interfacial polymerization The loose reverse osmosis composite membrane of amine.It is as follows：
1) 0.75wt%1,4- cyclohexanediamine aqueous solution impregnate polyether sulfone ultrafiltration supporting layer, after impregnating 120s, use air knife The Isosorbide-5-Nitrae of ultrafiltration supporting layer surplus-cyclohexanediamine aqueous solution is removed, is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.1wt%5- (N- sulfenamides) m-phthaloyl chloride The hexane solution of benzene is in contact 60s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2) using n-hexane is rinsed, 180s is then heat-treated under the conditions of 60 DEG C, prepared Obtain the loose reverse osmosis composite membrane of polyamide.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 99.76%, CaCl2It is de- Salt rate is that 99.05%, NaCl salt rejection rates are 70.70%, permeant flux 54.65LMH；It is to being rich in SO4 2-Ion it is with high salt hard The water softening power of water such as table 2.
Embodiment 2：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, aqueous phase solution, 5- are done with Isosorbide-5-Nitrae-cyclohexanediamine aqueous solution The hexamethylene toluene mixed solution of (N- sulfenamides) m-phthaloyl chloride does organic phase solution, and polyamides is prepared by interfacial polymerization The loose reverse osmosis composite membrane of amine.It is as follows：
1) 0.5wt%1,4- cyclohexanediamine aqueous solution impregnate polyether sulfone ultrafiltration supporting layer, will using air knife after impregnating 120s The Isosorbide-5-Nitrae of ultrafiltration supporting layer surplus-cyclohexanediamine aqueous solution removes, and is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.1wt%5- (N- sulfenamides) m-phthaloyl chloride The hexane solution of benzene is in contact 60s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2) using n-hexane is rinsed, 180s is then heat-treated under the conditions of 60 DEG C, prepared Obtain the loose reverse osmosis composite membrane of polyamide.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 99.02%, CaCl2It is de- Salt rate is that 98.3%, NaCl salt rejection rates are 67.8%, permeant flux 58.03LMH.
Embodiment 3：
In the present embodiment, using polysulphone super-filter membrane as supporting layer, aqueous phase solution, 5- (N- are done with Isosorbide-5-Nitrae-cyclohexanediamine aqueous solution Sulfenamide) the hexamethylene toluene mixed solution of m-phthaloyl chloride does organic phase solution, polyamide is prepared by interfacial polymerization Loose reverse osmosis composite membrane.It is as follows：
1) by 1.0wt%1,4- cyclohexanediamine aqueous solution dipping polysulfones ultrafiltration supporting layer, will using air knife after impregnating 120s The Isosorbide-5-Nitrae of ultrafiltration supporting layer surplus-cyclohexanediamine aqueous solution removes, and is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.10wt%5- (N- sulfenamides) m-phthaloyl chloride The hexane solution of benzene is in contact 60s, and by interface polymerization reaction, aramid layer is generated in polysulfones ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 180s under the conditions of 60 DEG C, is prepared into To polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 98.96%, CaCl2Desalination Rate is that 97.25%, NaCl salt rejection rates are 56.77%, permeant flux 43.5LMH.
Embodiment 4：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, aqueous phase solution is done with three (2- amino-ethyls) amine aqueous solutions, The hexamethylene toluene mixed solution of 5- (N- sulfenamides) m-phthaloyl chloride does organic phase solution, is prepared by interfacial polymerization poly- Amide composite membrane.It is as follows：
1) 1.0wt% tri- (2- amino-ethyls) amine aqueous solution is impregnated into polyether sulfone ultrafiltration supporting layer, after impregnating 120s, used Air knife removes three (2- amino-ethyls) amine aqueous solutions of ultrafiltration supporting layer surplus, is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.15wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 30s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 180s under the conditions of 60 DEG C, is prepared into To polyamide reverse osmosis composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 99.77%, CaCl2It is de- Salt rate is that 99.61%, NaCl salt rejection rates are 84.2%, permeant flux 44.41LMH；It is to being rich in SO4 2-Ion it is with high salt hard The water softening power of water such as table 2.
Embodiment 5：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, aqueous phase solution is done with three (2- amino-ethyls) amine aqueous solutions, The hexamethylene toluene mixed solution of 5- (N- sulfenamides) m-phthaloyl chloride does organic phase solution, is prepared by interfacial polymerization poly- Amide composite membrane.It is as follows：
1) 1.0wt% tri- (2- amino-ethyls) amine aqueous solution is impregnated into polyether sulfone ultrafiltration supporting layer, after impregnating 120s, used Air knife removes three (2- amino-ethyls) amine aqueous solutions of ultrafiltration supporting layer surplus, is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.15wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 10s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 180s under the conditions of 60 DEG C, is prepared into To polyamide reverse osmosis composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 99.26%, CaCl2It is de- Salt rate is that 98.44%, NaCl salt rejection rates are 80.54%, permeant flux 46.02LMH.
Embodiment 6：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, aqueous phase solution is done with three (2- amino-ethyls) amine aqueous solutions, The hexamethylene toluene mixed solution of 5- (N- sulfenamides) m-phthaloyl chloride does organic phase solution, is prepared by interfacial polymerization poly- Amide composite membrane.It is as follows：
1) 2.0wt% tri- (2- amino-ethyls) amine aqueous solution is impregnated into polyether sulfone ultrafiltration supporting layer, after impregnating 120s, used Air knife removes three (2- amino-ethyls) amine aqueous solutions of ultrafiltration supporting layer surplus, is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.3wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 10s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 60s under the conditions of 90 DEG C, is prepared into To polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 99.14%, CaCl2It is de- Salt rate is that 98.65%, NaCl salt rejection rates are 90.13%, permeant flux 22.32LMH.
Embodiment 7：
In the present embodiment, using polysulphone super-filter membrane as supporting layer, aqueous phase solution, 5- are with three (2- amino-ethyls) amine aqueous solutions The hexamethylene toluene mixed solution of (N- sulfenamides) m-phthaloyl chloride does organic phase solution, and polyamides is prepared by interfacial polymerization The loose reverse osmosis composite membrane of amine.It is as follows：
1) 1.5wt% tri- (2- amino-ethyls) amine aqueous solution is impregnated into polysulfones ultrafiltration supporting layer, after impregnating 120s, uses wind Knife removes three (2- amino-ethyls) amine aqueous solutions of ultrafiltration supporting layer surplus, is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.15wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 60s, and by interface polymerization reaction, aramid layer is generated in polysulfones ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 180s under the conditions of 60 DEG C, is prepared into To polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 96.71%, CaCl2Desalination Rate is that 98.74%, NaCl salt rejection rates are 76.55%, permeant flux 24.03LMH.
Embodiment 8：
In the present embodiment, using polysulphone super-filter membrane as supporting layer, aqueous phase solution, 5- are with three (2- amino-ethyls) amine aqueous solutions The hexamethylene toluene mixed solution of (N- sulfenamides) m-phthaloyl chloride does organic phase solution, and polyamides is prepared by interfacial polymerization The loose reverse osmosis composite membrane of amine.It is as follows：
1) 1.0wt% tri- (2- amino-ethyls) amine aqueous solution is impregnated into polysulfones ultrafiltration supporting layer, after impregnating 120s, uses wind Knife removes three (2- amino-ethyls) amine aqueous solutions of ultrafiltration supporting layer surplus, is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.15wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 60s, and by interface polymerization reaction, aramid layer is generated in polysulfones ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 90s under the conditions of 90 DEG C, is prepared into To polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 99.23%, CaCl2Desalination Rate is that 99.01%, NaCl salt rejection rates are 87.21%, permeant flux 17.23LMH.
Embodiment 9：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, it is molten that water phase is done with polyethyleneimine (MW70000) aqueous solution Liquid, the hexamethylene toluene mixed solution of 5- (N- sulfenamides) m-phthaloyl chloride does organic phase solution, by interfacial polymerization system The loose reverse osmosis composite membrane of standby polyamide.It is as follows：
1) 1.0wt% aq. polyethyleneimines are impregnated into polyether sulfone ultrafiltration supporting layer, it, will using air knife after impregnating 300s The aq. polyethyleneimine of ultrafiltration supporting layer surplus removes, and is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.15wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 300s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 120s under the conditions of 60 DEG C, is prepared into To polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 98.07%, CaCl2Desalination Rate is that 97.61%, NaCl salt rejection rates are 34.5%, permeant flux 45.81LMH.
Embodiment 10：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, aqueous phase solution, 5- (N- Asias sulphurs are done with 1,3 propane diamine solution Amide) the hexamethylene toluene mixed solution of m-phthaloyl chloride does organic phase solution, and it is loose to prepare polyamide by interfacial polymerization Reverse osmosis composite membrane.It is as follows：
1) by 1.5wt%1,3 propane diamine aqueous solutions dipping polyether sulfone ultrafiltration supporting layer, will using air knife after impregnating 120s The aq. polyethyleneimine of ultrafiltration supporting layer surplus removes, and is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.15wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 30s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 180s under the conditions of 60 DEG C, is prepared into To polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 99.12%, CaCl2Desalination Rate is that 98.91%, NaCl salt rejection rates are 78.5%, permeant flux 22.32LMH.
Embodiment 11：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, it is molten that water phase is done with polyethyleneimine (MW70000) aqueous solution Liquid, the hexamethylene toluene mixed solution of 5- (N- sulfenamides) m-phthaloyl chloride does organic phase solution, by interfacial polymerization system The loose reverse osmosis composite membrane of standby polyamide.It is as follows：
1) 0.75wt% aq. polyethyleneimines are impregnated into polyether sulfone ultrafiltration supporting layer, after impregnating 300s, uses air knife The aq. polyethyleneimine of ultrafiltration supporting layer surplus is removed, is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.05wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 300s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, 10min is then heat-treated under the conditions of 50 DEG C, prepared Obtain polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 96.21%, CaCl2Desalination Rate is that 94.02%, NaCl salt rejection rates are 33.1%, permeant flux 48.25LMH.
Embodiment 12：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, aqueous phase solution is done with diethylenetriamine solution, (N- is sub- by 5- Sulfonamide) the hexamethylene toluene mixed solution of m-phthaloyl chloride does organic phase solution, and preparing polyamide by interfacial polymerization dredges Loose reverse osmosis composite membrane.It is as follows：
1) 1.0wt% diethylenetriamines aqueous solution is impregnated into polyether sulfone ultrafiltration supporting layer, it, will using air knife after impregnating 120s The aq. polyethyleneimine of ultrafiltration supporting layer surplus removes, and is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.15wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 30s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 120s under the conditions of 60 DEG C, is prepared into To polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 98.7%, CaCl2Salt rejection rate It is 83.41% for 97.11%, NaCl salt rejection rates, permeant flux 14.2LMH.
Embodiment 13：
In the present embodiment, using poly (ether-sulfone) ultrafiltration membrane as supporting layer, aqueous phase solution, 5- (N- sulfenyls are done with ethylenediamine solution Amine) the hexamethylene toluene mixed solution of m-phthaloyl chloride does organic phase solution, and it is loose anti-to prepare polyamide by interfacial polymerization Osmosis composite membrane.It is as follows：
1) 2.0wt% ethylenediamine solutions are impregnated into polyether sulfone ultrafiltration supporting layer, after impregnating 120s, using air knife by ultrafiltration The aq. polyethyleneimine of supporting layer surplus removes, and is formed on its surface water phase liquid layer；
2) by the water phase liquid layer and the first containing 1.0wt% containing 0.1wt%5- (N- sulfenamides) m-phthaloyl chloride The cyclohexane solution of benzene is in contact 30s, and by interface polymerization reaction, aramid layer is generated in polyether sulfone ultrafiltration support layer surface；
3) composite membrane prepared by step 2 using n-hexane is rinsed, is then heat-treated 180s under the conditions of 60 DEG C, is prepared into To polyamide composite film.
Separation test, MgSO are carried out to polyamide composite film obtained above4Salt rejection rate is 98.12%, CaCl2Desalination Rate is that 97.23%, NaCl salt rejection rates are 85.15%, permeant flux 10.32LMH.
The property of high-salt wastewater used in 1 evaluating combined film water softening performance of table
With the loose reverse osmosis composite membrane of polyamide prepared by embodiment 1 and embodiment 4 under test pressure 1.5MPa into The test (mixed salt stoste composition such as table 1) of row 13500ppm mixed salts, test result is shown in Table 2.
Table 2 is to the water softening performance test result of mixed salt
From table 2 it can be seen that embodiment 1 and embodiment 3 also show mixed salt excellent softening power, wherein to solid Content, Ca2+And Mg2+Removal efficiency up to up to more than 99%.Thus illustrate, pass through N- sulfoamido acyl chlorides monomers and one The loose reverse osmosis composite membrane of polyamide prepared by grade aliphatic amine monomer, in charge efficiency and hole into the collective effect of sieve effect Under, to being rich in SO4 2-High-salt wastewater still have good water softening power.
The foregoing is merely presently preferred embodiments of the present invention, is not intended to limit the invention, it is all the present invention spirit and Within principle, any modification, equivalent replacement, improvement and so on should all be included in the protection scope of the present invention.

Claims (10)

1. a kind of preparation method of the loose reverse osmosis composite membrane of N- sulfenamides based polyamide, which is characterized in that including：
(1) will through ultrafiltration supporting layer pretreatment under conditions of normal pressure, room temperature, relative humidity are not higher than 70% in water phase amine 60-300s is impregnated in monomer solution, forms water phase liquid layer；Wherein, water phase amine monomers be primary aliphatic amine monomers, water phase amine A concentration of 0.5-2.0wt% of monomer；
(2) the water phase liquid layer with the organic solution containing organic phase activated monomer is in contact, is existed by interface polymerization reaction Ultrafiltration support layer surface generates aramid layer, and the interfacial polymerization time is 10s-300s, and it is loose that N- sulfenamide based polyamides are made Reverse osmosis composite membrane；
Wherein, organic phase activated monomer for at least one amido protecting group and at least two acid chloride groups aromatic series or Alicyclic organic matter, protected amino be N- sulfonamidos, a concentration of 0.005-0.3wt% of organic phase activated monomer.
2. the preparation method of the loose reverse osmosis composite membrane of N- sulfenamides based polyamide according to claim 1, feature It is, the preparation method further includes：
(3) product made from step (2) is post-processed, post-processing step includes：The product is handled at 50-90 DEG C Then 2-10min is cleaned with one or more combinations in n-hexane, pure water and water phase additive aqueous solution.
3. the preparation method of the loose reverse osmosis composite membrane of N- sulfenamides based polyamide according to claim 1, feature It is, in step (1),
To the ultrafiltration supporting layer pre-processed the specific steps are：Ultrafiltration supporting layer is used into isopropanol and deionized water successively It is cleaned, then removes excess surface water layer with air knife；
After the ultrafiltration supporting layer is impregnated in water phase amine monomers aqueous solution, the water phase amine for removing surface excess is purged with air knife Monomer solution.
4. according to the preparation side of the loose reverse osmosis composite membrane of claim 1-3 any one of them N- sulfenamide based polyamides Method, which is characterized in that the primary aliphatic monomer is d-glucosamine, hyperbranched polyethyleneimine, Isosorbide-5-Nitrae-cyclohexanediamine, 1,2- Cyclohexanediamine, 1,3- cyclohexanediamine, three (2- amino-ethyls) amine, three (2- amino methyls) amine, three (2- aminopropyls) amine, N, N- In two (amino-ethyl) ethylenediamines, ethylenediamine, 1,3- propane diamine, diethylenetriamines, trien and 1,4- butanediamine One kind.
5. according to the preparation side of the loose reverse osmosis composite membrane of claim 1-3 any one of them N- sulfenamide based polyamides Method, which is characterized in that the organic phase activated monomer is 1,3- bis- (N- sulfonamidos) benzoyl chloride, 5- (N- sulfenamides Base) two N- sulfenamides of m-phthaloyl chloride or 1,3- isophthalic.
6. according to the preparation side of the loose reverse osmosis composite membrane of claim 1-3 any one of them N- sulfenamide based polyamides Method, which is characterized in that in step (1), the water phase additive used is sub- for organic sulfonic acid, organic amine, alcohol, organophosphor, dimethyl One or more combinations in sulfone, acetone and quaternary ammonium salt.
7. according to the preparation side of the loose reverse osmosis composite membrane of claim 1-3 any one of them N- sulfenamide based polyamides Method, which is characterized in that in step (2), the organic solvent used is n-hexane, hexamethylene, normal heptane, toluene, benzene and isomeric alkane One or more combinations in hydrocarbon organic solvent.
8. according to the preparation side of the loose reverse osmosis composite membrane of claim 1-3 any one of them N- sulfenamide based polyamides Method, which is characterized in that the ultrafiltration supporting layer by polysulfones, polyether sulfone, polyimides, Kynoar and polyacrylonitrile and this One or more in the derivative of a little polymer are prepared.
It is loose reverse osmosis compound that 9. N- sulfenamide based polyamides are prepared in claim 1-8 any one of them preparation methods Film.
10. the loose reverse osmosis composite membrane of N- sulfenamides based polyamide according to claim 9, which is characterized in that described The separation layer thickness of N- sulfonamido polyamide composite films is 20-200nm.
CN201810024861.1A 2018-01-11 2018-01-11 A kind of N- sulfenamides based polyamide water softens loose reverse osmosis composite membrane and preparation method thereof Withdrawn CN108159891A (en)

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CN109289543A (en) * 2018-10-26 2019-02-01 中国石油大学(华东) One kind is from micropore high-flux nanofiltration composite membrane and preparation method thereof
CN111821865A (en) * 2019-04-22 2020-10-27 苏州苏瑞膜纳米科技有限公司 Composite membrane with separation function and vapor deposition preparation method thereof
CN112316752A (en) * 2020-11-04 2021-02-05 天津工业大学 Sulfonamide micromolecule surface modified polyamide composite membrane and preparation method thereof
CN112973449A (en) * 2019-12-12 2021-06-18 南京理工大学 Polyester composite reverse osmosis membrane with chlorine resistance and preparation method and application thereof
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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109289543A (en) * 2018-10-26 2019-02-01 中国石油大学(华东) One kind is from micropore high-flux nanofiltration composite membrane and preparation method thereof
CN111821865A (en) * 2019-04-22 2020-10-27 苏州苏瑞膜纳米科技有限公司 Composite membrane with separation function and vapor deposition preparation method thereof
CN111821865B (en) * 2019-04-22 2022-09-23 苏州苏瑞膜纳米科技有限公司 Composite membrane with separation function and vapor deposition preparation method thereof
CN112973449A (en) * 2019-12-12 2021-06-18 南京理工大学 Polyester composite reverse osmosis membrane with chlorine resistance and preparation method and application thereof
CN112973449B (en) * 2019-12-12 2022-06-10 南京理工大学 Polyester composite reverse osmosis membrane with chlorine resistance as body and preparation method and application thereof
CN112316752A (en) * 2020-11-04 2021-02-05 天津工业大学 Sulfonamide micromolecule surface modified polyamide composite membrane and preparation method thereof
CN114849501A (en) * 2022-05-30 2022-08-05 沃顿科技股份有限公司 Preparation method of nanofiltration membrane and nanofiltration membrane prepared by same
WO2024174089A1 (en) * 2023-02-21 2024-08-29 万华化学集团股份有限公司 Polyamide composite membrane and preparation method therefor

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