CN1583233A - Polyamide reverse osmosis composite membrane and preparing method thereof - Google Patents
Polyamide reverse osmosis composite membrane and preparing method thereof Download PDFInfo
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- CN1583233A CN1583233A CN 200410025245 CN200410025245A CN1583233A CN 1583233 A CN1583233 A CN 1583233A CN 200410025245 CN200410025245 CN 200410025245 CN 200410025245 A CN200410025245 A CN 200410025245A CN 1583233 A CN1583233 A CN 1583233A
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Abstract
A reverse-osmosis composite polyamide membrane features that a super-thin functional aromatic polyamid layer is attached on a porous supporting membrane. Its preparing process features its single-surface polymerizing reaction on modified polybasic acyl chloride solution.
Description
Technical field
The present invention relates to a kind of water separation technology, specifically is a kind of novel polyamide reverse osmosis composite membrane and preparation method thereof.
Background technology
Reverse osmosis composite membrane is that one deck ultrathin functional layer is deposited to suitable micropore support membrane surface, aperture, and depositional mode mainly contains surface-coated, interfacial polycondensation and in-situ polymerization etc.Composite membrane has many advantages than asymmetric membrane: it can make every layer to reach optimum performance by cutting out.Ultrathin functional layer can be optimized to desirable selection permeability, and support membrane can reach best intensity and pressure tightness.In addition, composite membrane can make the material that is difficult to form asymmetric membrane form ultrathin membrane, as because solvent limitation and crosslinking polymer can form composite membrane by in-situ polymerization or interfacial polycondensation.
US Patent4 in 1981 such as Cadotte, 277,344 adopt interface polycondensation to pass through the compound one deck aromatic polyamides of interfacial polycondensation film on the polysulfones support membrane, this film is that the polysulfones support membrane is immersed in the buffer solution of m-phenylene diamine (MPD), after extracting, pyromellitic trimethylsilyl chloride solution in the covering, reaction a period of time post rinse, and carry out post processing.This film ultrathin functional layer is mainly crosslinked aromatic polyamides, and its chemical structural formula can be expressed as:
Uemura etc. were at US Patent4 in 1988, adopting interface polycondensation in 761,234 is crosslinking agent with equal benzene triamine, reacts compound one deck aromatic polyamides film with m-phthaloyl chloride on support membrane, salt rejection rate is greater than 99%, but its used equal benzene triamine is difficult to obtain.The chemical structural formula of aromatic polyamides can be expressed as in its compound ultrathin functional layer:
In addition, US Patent5,576,057, US Patent 5,989,426, US Patent 6,162, and 358, USPatent 6,464, patents such as 873 also are that the polysulfones support membrane is immersed in the polyamine aqueous solution, immerse polynary solution of acid chloride after extracting again, and reaction a period of time post rinse also carries out post processing and obtains product.
Above-mentioned technology one is that raw material ratio is rareer, and is mostly support membrane is carried out two-sided polymerization in its preparation, and two-sided rinsing causes the waste of a face polymeric material, has also prolonged preparation time.
Summary of the invention
The technical issues that need to address of the present invention are, the composite membrane ultrathin functional layer except contain the acid amides functional group (CO-NH-), also contain the urea functional group (NH-CO-NH-) or the amido formate functional group (OCO-NH-), the hydrophily of ultrathin functional layer is improved.In addition, on the aromatic ring of polyamine, substituting group is arranged, be beneficial to the chlorine resistance that strengthens ultrathin functional layer.
Another technical problem that the present invention need solve is to save polymeric material and preparation time.
Novel polyamide reverse osmosis composite membrane of the present invention, it is characterized in that being compounded with one deck aromatic polyamides ultrathin functional layer by containing the polynary acyl chlorides interfacial polycondensation of substituent aromatic polyamine and modified aromatic on the aromatic rings on the porous support membrane, its chemical structural formula can be expressed as:
In the formula X be-NH-CO-NH-or-OCO-NH-; Y corresponds to-NH
2Or-OH, or-COOH; Z is-Cl or-NO
2Or-CH
3
The preparation method of novel polyamide reverse osmosis composite membrane of the present invention is characterized in that the polysulfones support membrane directly is immersed in the polyamines solution, behind squeegee roll extrusion support membrane surface, carries out the single face interface polymerization reaction with the modified multicomponent solution of acid chloride; The interface polymerization reaction that generates polyamide active layer only carries out on polysulfones support membrane surface, and composite membrane dries in the shade in air, and again through heat treatment, rinsing obtains reverse osmosis composite membrane;
The weight ratio that contains substituent aromatic polyamine and the polynary acyl chlorides of described modified aromatic on the described aromatic rings is 0.1～40: 1.
Wherein modified multicomponent acyl chlorides organic solvent can be a trifluorotrichloroethane, n-hexane, a kind of in the heptane.
As preferably, the weight ratio that contains substituent aromatic polyamine and the polynary acyl chlorides of described modified aromatic on the described aromatic rings is 1～40: 1.
Contain substituent aromatic polyamine on the described aromatic rings and comprise 4-chlorine m-phenylene diamine (MPD) at least, 4-nitro m-phenylene diamine (MPD) and 2, in the 4-diaminotoluene one.
The polynary acyl chlorides of described modified aromatic comprises 5-isocyanates-isophthaloyl chlorine at least, 5-oxygen formyl chloride-isophthaloyl chlorine, in the m-phthaloyl chloride one.
This novel polyamide reverse osmosis composite membrane also can be prepared into hollow-fibre membrane.
Novel polyamide reverse osmosis composite membrane of the present invention, its salt rejection rate and water flux are not less than prior art, also have raw material and are easy to get, can be according to self-controls such as Chinese patent literature 200410016957.1 and 200410017732.8, the preparation method is reasonable, and the time shortens, the advantage that material is relatively saved.
Specific implementation method
Following examples provide the explanation of novel reverse osmosis composite membrane and their desalting performance.Yet these embodiment only provide as an illustration rather than limit the present invention.
The present invention is the UDEL PS3500 polysulfones with 16%, 0.3% water and 0.1% surfactant are dissolved in N, the N-dimethylacetylamide is coated with and scrapes on polyester non-woven fabric, immerses then in the water to remove that to obtain molecular cut off (MWCO) after desolvating be about 20,000 support membrane.Wherein surfactant comprises alkyl phenol polyoxy Acetoxon acid esters at least, a kind of in dodecyl sodium sulfate and the alkyl phenol polyoxy Acetoxon hydrochlorate.
The polysulfones support membrane single face of hygrometric state is immersed in the polyamine solution, after extracting with squeegee roll extrusion support membrane surface, contacts with modified multicomponent solution of acid chloride single face and to carry out interface polymerization reaction.Composite membrane dried in the shade in air 2 minutes, and again through two step heat treatments: the first step is to handle 3～5 minutes down at 40～70 ℃, and second step was to handle 3～5 minutes down at 70～110 ℃.Then carry out two step rinsings again: the first step is to be rinsing 10～40 minutes in 15% the aqueous solution at 30～60 ℃ methyl alcohol part by weight, and second step was rinsing 10～40 minutes in 30～60 ℃ water.The composite membrane performance of this method preparation obviously is better than the conventional composite membrane that immerses the interfacial polymerization preparation, and easilier in rinse cycle washes out unnecessary polyamine.
Embodiment 1-3.UDEL PS3500 polysulfones with 16%, 0.3% water and 0.1% polyoxyethylene nonyl phenyl Acetoxon acid esters are dissolved in N, and dinethylformamide is coated with and scrapes on polyester non-woven fabric, immerse then in the water to remove and obtain the support membrane that molecular cut off is 1-2 ten thousand after desolvating, hygrometric state is preserved standby.
It is (to be followed successively by 4-chlorine m-phenylene diamine (MPD) in 2% the aqueous solution that the polysulfones support membrane single face of hygrometric state is immersed in the polyamine part by weight, 4-nitro m-phenylene diamine (MPD) or 2,4-two amido toluene) 2 minutes, after extracting with squeegee roll extrusion support membrane surface, be that 0.1～0.15% organic solution single face contacts and carried out interface polymerization reaction 20～40 seconds with 5-isocyanates-isophthaloyl chlorine (ICIC) part by weight.Composite membrane dried in the shade in air 2 minutes, and again through two step heat treatments: the first step is to handle 3～5 minutes down at 40～70 ℃, and second step was to handle 3～5 minutes down at 70～110 ℃.Then carry out two step rinsings again: the first step is to be rinsing 10～40 minutes in 15% the aqueous solution at 30～60 ℃ methyl alcohol part by weight, and second step was rinsing 10～40 minutes in 30～60 ℃ water, composite membrane.The composite membrane of preparation is kept in the water, and at the sodium-chloride water solution of 2000ppm, operating pressure is 225psi, and operating temperature is its desalting performance of test under 25 ℃ the condition.
The polynary acyl chlorides solvent flux of embodiment polyamine (l/m
2.d) salt rejection rate
1 4-chlorine m-phenylene diamine (MPD) (2%) ICIC (0.1%) trifluorotrichloroethane 45.6 95.81
2 4-nitro m-phenylene diamine (MPD) (2%) ICIC (0.12%) n-hexanes 35.8 98.58
32,4-diaminotoluene (2%) ICIC (0.15%) heptane 34.2 98.40
Embodiment 4-6.Embodiment as the front, as stated above, employing polyamine part by weight is 2% the aqueous solution (4-chlorine m-phenylene diamine (MPD) or 4-nitro m-phenylene diamine (MPD) or 2,4-two amido toluene), 5-isocyanates-isophthaloyl chlorine part by weight be 0.05～0.1% and m-phthaloyl chloride (IPC) part by weight be that 0.05% organic solution prepares reverse osmosis composite membrane.These several embodiment investigate to add the influence of m-phthaloyl chloride to film properties.
The polynary acyl chlorides solvent flux of embodiment polyamine (l/m
2.d) salt rejection rate
4 4-chlorine m-phenylene diamine (MPD) (2%) ICIC (0.05%)/trifluorotrichloroethane 47.6 94.78
IPC(0.05％)
5 4-nitro m-phenylene diamine (MPD) (2%) ICIC (0.08%)/n-hexane 36.2 98.50
IPC(0.05％)
62,4-diaminotoluene (2%) ICIC (0.10%)/heptane 34.7 97.24
IPC(0.05％)
Embodiment 7-9.Embodiment as the front, as stated above, employing polyamine part by weight is 2% the aqueous solution (4-chlorine m-phenylene diamine (MPD) or 4-nitro m-phenylene diamine (MPD) or 2,4-two amido toluene), 5-oxygen formyl chloride-isophthaloyl chlorine (CFIC) part by weight is that 0.15～0.2% organic solution prepares reverse osmosis composite membrane.
The polynary acyl chlorides solvent flux of embodiment polyamine (l/m
2.d) salt rejection rate
7 4-chlorine m-phenylene diamine (MPD) (2%) CFIC (0.15%) trifluorotrichloroethanes 41.2 98.78
8 4-nitro m-phenylene diamine (MPD) (2%) CFIC (0.17%) normal hexanes 34.5 99.40
92,4-diaminotoluene (2%) CFIC (0.20%) heptane 32.3 99.24
Embodiment 10-12.Embodiment as the front, as stated above, employing polyamine part by weight is 2% the aqueous solution (4-chlorine m-phenylene diamine (MPD) or 4-nitro m-phenylene diamine (MPD) or 2,4-two amido toluene), 5-oxygen formyl chloride-isophthaloyl chlorine part by weight be 0.1～0.15% and m-phthaloyl chloride chlorine part by weight be that 0.05% organic solution prepares reverse osmosis composite membrane.These several embodiment investigate to add the influence of m-phthaloyl chloride to film properties.
The polynary acyl chlorides solvent flux of embodiment polyamine (l/m
2.d) salt rejection rate
10 4-chlorine m-phenylene diamine (MPD) (2%) CFIC (0.10%)/trifluorotrichloroethane 43.5 98.12
IPC(0.05％)
11 4-nitro m-phenylene diamine (MPD) (2%) CFIC (0.13%)/normal hexane 35.7 99.15
IPC(0.05％)
12 2,4-diaminotoluene (2%) CFIC (0.15%)/heptane 33.3 97.24
IPC(0.05％)
Claims (5)
1, a kind of novel polyamide reverse osmosis composite membrane, it is characterized in that being compounded with one deck aromatic polyamides ultrathin functional layer by containing the polynary acyl chlorides interfacial polycondensation of substituent aromatic polyamine and modified aromatic on the aromatic rings on the porous support membrane, its chemical structural formula can be expressed as:
In the formula X be-NH-CO-NH-or-OCO-NH-; Y corresponds to-NH
2Or-OH, or-COOH; Z is-Cl or-NO
2Or-CH
3
2, a kind of preparation method of novel polyamide reverse osmosis composite membrane is characterized in that the polysulfones support membrane directly is immersed in the polyamine solution, behind squeegee roll extrusion support membrane surface, carries out the single face interface polymerization reaction with the modified multicomponent solution of acid chloride; The interface polymerization reaction that generates polyamide active layer only carries out on polysulfones support membrane surface, and composite membrane dries in the shade in air, and again through heat treatment, rinsing obtains reverse osmosis composite membrane; The weight ratio that contains substituent aromatic polyamine and the polynary acyl chlorides of described modified aromatic on the described aromatic rings is 0.1～40: 1.
3, the preparation method of reverse osmosis composite membrane according to claim 2, the weight ratio that it is characterized in that containing on the described aromatic rings substituent aromatic polyamine and the polynary acyl chlorides of described modified aromatic is 1～40: 1.
4,, it is characterized in that containing on the described aromatic rings substituent aromatic polyamine and comprise 4-chlorine m-phenylene diamine (MPD) at least, 4-nitro m-phenylene diamine (MPD) and 2, in the 4-diaminotoluene one according to the preparation method of claim 2 or 3 described reverse osmosis composite membranes.
5,, it is characterized in that the polynary acyl chlorides of described modified aromatic comprises 5-isocyanates-isophthaloyl chlorine at least, 5-oxygen formyl chloride-isophthaloyl chlorine, in the m-phthaloyl chloride one according to the preparation method of claim 2 or 3 described reverse osmosis composite membranes.
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008025259A1 (en) * | 2006-08-25 | 2008-03-06 | Vontron Membrane Technology Co., Ltd. | Oxidation-resistant composite reverse osmosis membrane |
| CN101502763B (en) * | 2009-02-10 | 2011-06-22 | 杭州水处理技术研究开发中心有限公司 | Novel biological contamination-resistant ultrathin compound film and preparation method thereof |
| CN102133507A (en) * | 2011-02-28 | 2011-07-27 | 浙江理工大学 | High-desalination reverse osmosis composite membrane |
| CN102380257A (en) * | 2010-09-02 | 2012-03-21 | 财团法人工业技术研究院 | Filtration material for desalination |
| US8567611B2 (en) | 2009-03-02 | 2013-10-29 | Industrial Technology Research Institute | Filtration material |
| CN103764264A (en) * | 2011-08-31 | 2014-04-30 | 陶氏环球技术有限责任公司 | Composite polyamide membrane derived from monomer including amine-reactive and phosphorous-containing functional groups |
| CN104470627A (en) * | 2012-07-19 | 2015-03-25 | 陶氏环球技术有限责任公司 | Composite polyamide membrane |
| CN105163837A (en) * | 2013-05-03 | 2015-12-16 | 陶氏环球技术有限责任公司 | Composite polyamide membrane derived from aliphatic acyclic tertiary amine compound |
| CN105358238A (en) * | 2013-07-04 | 2016-02-24 | 巴斯夫欧洲公司 | Multiple channel membranes |
| CN105457494A (en) * | 2014-09-09 | 2016-04-06 | 贵阳时代沃顿科技有限公司 | Nanostructure high-flux reverse osmosis membrane for seawater desalination and preparation method therefor |
-
2004
- 2004-06-12 CN CN 200410025245 patent/CN1263535C/en not_active Expired - Fee Related
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008025259A1 (en) * | 2006-08-25 | 2008-03-06 | Vontron Membrane Technology Co., Ltd. | Oxidation-resistant composite reverse osmosis membrane |
| CN101502763B (en) * | 2009-02-10 | 2011-06-22 | 杭州水处理技术研究开发中心有限公司 | Novel biological contamination-resistant ultrathin compound film and preparation method thereof |
| US8567611B2 (en) | 2009-03-02 | 2013-10-29 | Industrial Technology Research Institute | Filtration material |
| CN102380257A (en) * | 2010-09-02 | 2012-03-21 | 财团法人工业技术研究院 | Filtration material for desalination |
| CN102380257B (en) * | 2010-09-02 | 2013-11-06 | 财团法人工业技术研究院 | Filtration material for desalination |
| CN102133507A (en) * | 2011-02-28 | 2011-07-27 | 浙江理工大学 | High-desalination reverse osmosis composite membrane |
| CN103764264A (en) * | 2011-08-31 | 2014-04-30 | 陶氏环球技术有限责任公司 | Composite polyamide membrane derived from monomer including amine-reactive and phosphorous-containing functional groups |
| CN103764264B (en) * | 2011-08-31 | 2016-11-16 | 陶氏环球技术有限责任公司 | It is derived from the composite polyamide membranes of the monomer comprising amine reactive functional groups and phosphorous functional group |
| CN104470627A (en) * | 2012-07-19 | 2015-03-25 | 陶氏环球技术有限责任公司 | Composite polyamide membrane |
| CN104470627B (en) * | 2012-07-19 | 2018-05-11 | 陶氏环球技术有限责任公司 | Composite polyamide membranes |
| CN105163837A (en) * | 2013-05-03 | 2015-12-16 | 陶氏环球技术有限责任公司 | Composite polyamide membrane derived from aliphatic acyclic tertiary amine compound |
| CN105163837B (en) * | 2013-05-03 | 2017-05-10 | 陶氏环球技术有限责任公司 | Composite polyamide membrane derived from aliphatic acyclic tertiary amine compound |
| CN105358238A (en) * | 2013-07-04 | 2016-02-24 | 巴斯夫欧洲公司 | Multiple channel membranes |
| CN105457494A (en) * | 2014-09-09 | 2016-04-06 | 贵阳时代沃顿科技有限公司 | Nanostructure high-flux reverse osmosis membrane for seawater desalination and preparation method therefor |
| CN105457494B (en) * | 2014-09-09 | 2018-02-13 | 贵阳时代沃顿科技有限公司 | A kind of nanostructured high flux seawater desalination reverse osmosis film and preparation method thereof |
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| CN1263535C (en) | 2006-07-12 |
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Assignee: HANGZHOU BEIDOUXING MEMBRANE Co.,Ltd. Assignor: HANGZHOU WATER TREATMENT TECHNOLOGY DEVELOPMENT CENTER Co.,Ltd. Contract record no.: 2011330000897 Denomination of invention: Polyamide reverse osmosis composite membrane and preparing method thereof Granted publication date: 20060712 License type: Exclusive License Open date: 20050223 Record date: 20110705 |
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