WO1992011081A1 - Membrane pour la separation de melanges gazeux, procede pour sa fabrication, ainsi que son utilisation - Google Patents

Membrane pour la separation de melanges gazeux, procede pour sa fabrication, ainsi que son utilisation Download PDF

Info

Publication number
WO1992011081A1
WO1992011081A1 PCT/EP1991/002395 EP9102395W WO9211081A1 WO 1992011081 A1 WO1992011081 A1 WO 1992011081A1 EP 9102395 W EP9102395 W EP 9102395W WO 9211081 A1 WO9211081 A1 WO 9211081A1
Authority
WO
WIPO (PCT)
Prior art keywords
polymer
membrane
carrier
membrane according
side chain
Prior art date
Application number
PCT/EP1991/002395
Other languages
German (de)
English (en)
Inventor
Hans-Dieter Lehmann
Original Assignee
Nmi Naturwissenschaftliches Und Medizinisches Institut An Der Universität Tübingen In Reutlingen
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nmi Naturwissenschaftliches Und Medizinisches Institut An Der Universität Tübingen In Reutlingen filed Critical Nmi Naturwissenschaftliches Und Medizinisches Institut An Der Universität Tübingen In Reutlingen
Publication of WO1992011081A1 publication Critical patent/WO1992011081A1/fr

Links

Classifications

    • 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
    • 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
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06—Organic material
    • B01D71/08—Polysaccharides
    • B01D71/12—Cellulose derivatives
    • B01D71/22—Cellulose ethers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F251/00—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof
    • C08F251/02—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof on to cellulose or derivatives thereof

Definitions

  • the invention relates to a membrane for separating gas mixtures, a process for their production and their use for the selective separation of gas mixtures.
  • a polymer which is to be used for the production of gas separation membranes must not only have a high permeability but also a high selectivity for individual components of a gas mixture. It should be able to be processed into very thin layers with high mechanical strength.
  • the permeability is high when the free volume in the molecular chain structure of the polymer is high, e.g. B. when bulky groups and movable chain segments are present.
  • examples of such polymers are silicones and trimethylsilyl-substituted polyacetylenes (cf. Y. Icharaku, SA Stern, An Investigation of the High Gas Permeability of Poly (1-trimethylsilyl-l-propylene), J. Membr. Sei. , Vol. 34 (1987), p. 5). In these membranes of high permeability made from such polymers, however, the selectivity is insufficient.
  • Polymers based on natural and renewable raw materials that have a wide range of industrial uses are increasingly being used in industry. It is enough e.g. in the case of cellulose from the manufacture of membranes for medical and technical applications to the use of liquid crystalline solutions of cellulose derivatives in the optical industry.
  • Certain polysaccharide derivatives have liquid-crystalline properties due to the stiffness of the main polymer chain ("rigid polymer"). They can therefore be used, for example, in the field of optics; cellulose derivatives with side chains (ethers or esters of organic and inorganic acids) are compiled by DG Gray (Liquid Crystalline Cellulose Derivatives, J. Appl. Pol. Sei., Appl. Pol. Symp., Vol. 37 (1983), p. 179).
  • DG Gray Liquid Crystalline Cellulose Derivatives, J. Appl. Pol. Sei., Appl. Pol. Symp., Vol. 37 (1983), p. 179).
  • Composite membranes are known as gas separation membranes. These composite membranes consist of a basic membrane and a coating.
  • the basic membrane is built integrally-asymmetrically, i.e.
  • a porous, flat support structure with a layer thickness of approx. 100-200 ⁇ m has pores on one side, which taper towards the other side in such a way that there is a relatively dense, approx. 0.1 - approx. 0 ⁇ m thin skin (“Skin”) is formed.
  • This "skin” represents the separating layer, which selects the properties of the base membrane when separating mixtures of liquid media e.g. with the help of reverse osmosis or ultrafiltration.
  • the "skin" of the base membrane for sealing the pin-holes be additionally coated with a thin coating, e.g. made of silicone or a silicone copoly eren.
  • This very thin coating does not perform any mechanically stabilizing function, but prevents convective gas transport through the pin holes in the "skin" of the integral-asymmetrical basic membrane.
  • the present invention is therefore based on the object (the technical problem) of providing new membranes with high permeability and, at the same time, high selectivity for the separation of gas mixtures and a simple process for their production.
  • the invention thus relates to a membrane for separating gas mixtures, comprising
  • both the side chains of the polymer (A) and the support (B) are preferably hydrophobic.
  • long side chain means a side chain which has more than 4 atoms without branching, but can also have additional branches.
  • An important advantage of the membrane according to the invention is on the one hand the high selectivity in the separation of gas mixtures and on the other hand the high permeability for the component to be separated or for the undesired components of the gas mixture. This advantage is based in particular on the synergistic effect which comes about according to the invention through the interaction of the polymer (A) and the carrier (B).
  • a thick film consisting only of polymer (A) is anisotropic according to the results of the X-ray scattering (flat chamber). Since the side chains may serve as a fixed solvent for the desired gas component, the properties of these gas separating membranes can be adjusted both by the degree of orientation and by modifying the inner surfaces with the aid of non-volatile additives.
  • the selectivity of the membrane according to the invention can be adapted to the component of the gas mixture to be selected by a suitable choice of the movable side chain and / or the type of modification thereof.
  • the membrane according to the invention can contain additives to improve the solubility of the gas component to be separated, for example amines when CO 2 is removed or fluorine-containing compounds when oxygen is removed.
  • the carrier (B) forms the major part of the layer thickness of the resulting membrane according to the invention in relation to polymer (A). In the small layer thicknesses present in the membrane according to the invention, the polymer (A) only makes a minor contribution to the mechanical strength of the membrane.
  • the thickness of the membrane according to the invention is preferably approximately 5 to 100 ⁇ m, more preferably approximately 10 to 50 ⁇ m and most preferably approximately 25 ⁇ m.
  • the layer thickness of the separating layer made of polymer (A) is in the range up to approximately 5 ⁇ m, preferably up to approximately 1 ⁇ m and most preferably approximately 0.1 ⁇ m.
  • the lower limit for the layer thickness of the separating layer is determined by the size of the pore diameter in the carrier.
  • the layer thickness should be selected so that all pores of the support are sealed and the membrane no longer has any pin holes.
  • a preferred embodiment according to the invention is a symmetrical membrane in which the polymer (A) is a polysaccharide derivative with longer side chains, more preferably a cellulose derivative with unsubstituted or substituted alkyl or arylalkyl ether side chains.
  • the carrier (B) preferably consists of a polyalkene homo- or copolymer, more preferably of a polyolefin homo- or copolymer of monomers having 2 to 8 carbon atoms and most preferably of polypropylene.
  • the carrier can be designed in different forms, e.g. flat or in the form of hollow threads. These carriers can be made by known methods or are commercially available.
  • the porosity of the support (B) should be as high as possible with a pore size distribution that is as uniform as possible.
  • a porosity of around 40% can be achieved.
  • the membrane according to the invention comprises cyanoethyl alkyl cellulose ethers, such as cyanoethyl propyl cellulose ether, as polymer (A) and gas-permeable polypropylene as carrier (B).
  • Another object of the invention is a method for producing the membrane according to the invention, comprising the steps
  • the polymer is preferably applied in a thin layer to both sides of the support used according to the invention. This will e.g. achieved by immersing the carrier in a solution of the polymer.
  • the membrane obtained in this way can additionally be subjected to a normal corona discharge or plasma treatment in order to reduce the solubility or swellability of the membrane in solvents.
  • such a polymer can be produced by introducing the movable side chains into a chain-rigid polymer.
  • the polymer (A) is reacted by reacting an ⁇ , ⁇ -unsaturated compound, such as Acrylonitrile or methacrylonitrile, as a functional group on a side chain of the rigid polymer, such as hydroxyalkyl cellulose, is prepared in tert-butanol as a solvent. In this way, groups with anchoring effect are introduced into the rigid polymer.
  • an ⁇ , ⁇ -unsaturated compound such as Acrylonitrile or methacrylonitrile
  • hydroxyalkyl celluloses such as hydroxyethyl or hydroxypropyl cellulose
  • high molecular weight cellulose derivatives are available which can be used according to the invention.
  • they are water-soluble and therefore not suitable for the production of hydrophobic membranes.
  • ⁇ , ⁇ -unsaturated compounds such as acrylonitrile or methacrylonitrile
  • polymers which are good in organic solvents, such as acetone or tetrahydrofuran (THF), but are not soluble in water.
  • the polymers produced in this way are capable of self-organization 11 , ie they can form a specific molecular structure under certain conditions. For example, such self-organization takes place in the production of layers of polymer (A) by evaporation of solutions on the invention used according to the carrier (B) instead.
  • the invention furthermore relates to the use of the membranes according to the invention for the selective separation of gas mixtures, in particular gas mixtures which contain at least two gases from the group N 2 , 0 2 , C0 2 , H 2 , noble gases, methane and other low-boiling hydrocarbons .
  • the examples illustrate the invention without restricting it. Unless otherwise specified, the percentages in the examples relate to percentages by weight.
  • the indicated molecular weights are number average of the molecular weight (Mn).
  • the product thus obtained is used as polymer (A) in the production of the membrane according to the invention.
  • Microporous sheet carriers made of polypropylene (Celgard * ⁇ Type 2400 from Hoechst-Celanese, thickness 25 ⁇ m, porosity 38%, specified pore size 0.04 ⁇ m) were immersed in acetone solutions of the product according to production example 1.1. At a concentration of 0.6% of polymer (A) in the solution, pore-free membranes were obtained, which proved to be tight in the bubble test using a differential pressure of 3 ⁇ 10 5 Pa, although the weight gain was only approx Was 2.5%.
  • Microporous flat supports made of polypropylene (Celgard® 2400) were immersed in 0.8% THF solutions of the reaction product according to preparation example 1.2, dense, pore-free membranes being obtained in the bubble test.
  • Membranes according to the invention according to production example 2.1 or 2.2 were treated with cold plasma (H 2 , N 2 , 0- > or CH 4 ) at 133 Pa. This made their surfaces insoluble in organic solvents.
  • the unit Barrer is defined as cm 3 (STP) x cm / cm 2 xsx (cm Hg) multiplied by the factor 10 ⁇ 10 , where STP means standard state for pressure and temperature (ie 101325 Pa and 273.15 K). 4. Comparative examples
  • Comparative Example 4.1 shows that a polymer used in accordance with only the dung OF INVENTION ⁇ (A) produced film has no selectivity in the separation of gas mixtures.
  • Comparative Examples 4.2 and 4.3 show that no Mem ⁇ membranes for the selective separation of gas mixtures were obtained, hydrophobic if either the polymer (A) hydrophilic and the carrier (B) or hydrophobic polymer (A) and the carrier (B) are hydrophilic .
  • Comparative example 4.4 shows that when chain-rigid polymers with a chain length of less than 5 atoms are used in the unbranched side chain (for example cellulose triacetate, which is prepared as described above for tion of known integral-asymmetric gas separation membranes) is used as the polymer (A), membranes are obtained which have a low selectivity only at low transmembrane pressure differences.
  • chain-rigid polymers with a chain length of less than 5 atoms for example cellulose triacetate, which is prepared as described above for tion of known integral-asymmetric gas separation membranes

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

La présente invention se rapporte à des membranes pour la séparation de mélanges gazeux et au procédé pour sa fabrication, les membranes comportant un polymère à chaîne rigide avec des chaînes latérales mobiles et un support perméable aux gaz. La séparation sélective des mélanges gazeux au moyen des membranes selon l'invention se base en particulier sur un effet synergique qui se produit, selon l'invention, par le concours du polymère modifié à chaîne rigide et du support perméable aux gaz.
PCT/EP1991/002395 1990-12-17 1991-12-12 Membrane pour la separation de melanges gazeux, procede pour sa fabrication, ainsi que son utilisation WO1992011081A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4040363A DE4040363A1 (de) 1990-12-17 1990-12-17 Polymere fuer die herstellung von folien, membranen, formkoerpern und funktionalisierten oberflaechen auf basis von polysacchariden
DEP4040363.7 1990-12-17

Publications (1)

Publication Number Publication Date
WO1992011081A1 true WO1992011081A1 (fr) 1992-07-09

Family

ID=6420583

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1991/002395 WO1992011081A1 (fr) 1990-12-17 1991-12-12 Membrane pour la separation de melanges gazeux, procede pour sa fabrication, ainsi que son utilisation

Country Status (2)

Country Link
DE (1) DE4040363A1 (fr)
WO (1) WO1992011081A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5997815A (en) * 1997-02-14 1999-12-07 Huels Aktiengesellschaft Article with antimicrobial coating

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19910466C2 (de) * 1999-03-10 2001-03-15 Geesthacht Gkss Forschung Verfahren zur Herstellung einer hydrophilen Hohlfadenkompositmembran

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0094226A2 (fr) * 1982-05-07 1983-11-16 Pall Corporation Systèmes de filtration
JPS62237904A (ja) * 1986-04-08 1987-10-17 Ube Ind Ltd 多孔質中空糸膜
EP0257635A2 (fr) * 1986-08-27 1988-03-02 Dow Danmark A/S Membrane polymère poreuse et perméable à propriétés hydrophiles, sa méthode de fabrication et son emploi
WO1988002653A1 (fr) * 1986-10-20 1988-04-21 Brunswick Corporation Membranes a film mince d'ultrafiltration
US4871378A (en) * 1987-12-11 1989-10-03 Membrane Technology & Research, Inc. Ultrathin ethylcellulose/poly(4-methylpentene-1) permselective membranes

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0094226A2 (fr) * 1982-05-07 1983-11-16 Pall Corporation Systèmes de filtration
JPS62237904A (ja) * 1986-04-08 1987-10-17 Ube Ind Ltd 多孔質中空糸膜
EP0257635A2 (fr) * 1986-08-27 1988-03-02 Dow Danmark A/S Membrane polymère poreuse et perméable à propriétés hydrophiles, sa méthode de fabrication et son emploi
WO1988002653A1 (fr) * 1986-10-20 1988-04-21 Brunswick Corporation Membranes a film mince d'ultrafiltration
US4871378A (en) * 1987-12-11 1989-10-03 Membrane Technology & Research, Inc. Ultrathin ethylcellulose/poly(4-methylpentene-1) permselective membranes

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Band 12, Nr. 110 (C-486)[2957] 8. April 1988, & JP, A, 62237904 (UBE IND. LTD) 17. Oktober 1987, siehe Zusammenfassung *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5997815A (en) * 1997-02-14 1999-12-07 Huels Aktiengesellschaft Article with antimicrobial coating

Also Published As

Publication number Publication date
DE4040363A1 (de) 1992-06-25

Similar Documents

Publication Publication Date Title
DE2703587C2 (de) Verfahren zur Herstellung von semipermeablen Membranen
DE2539408C3 (de) Membrane, Verfahren zu ihrer Herstellung und ihre Verwendung zur umgekehrten Osmose und Ultrafiltration
EP2695668B1 (fr) Procédé de fabrication d'une membrane de filtration thermosensible et membrane de filtration thermosensible
EP1712270B1 (fr) Matériau composite, en particulier membrane composite et son procédé de fabrication
EP0162964B1 (fr) Procédé de fabrication d'une membrane asymétrique
EP3003538B1 (fr) Membrane de polyfluorure de vinylidène microporeuse
WO2008034487A1 (fr) Membrane isoporeuse et son procédé de fabrication
DE3525235C1 (de) Verfahren zur Herstellung und Erhoehung der Selektivitaet einer integralasymmetrischen Membran
DE3716916A1 (de) Verfahren zur herstellung einer integralasymmetrischen membran
DE3415624A1 (de) Verbundmembran zur gastrennung
DE3936997A1 (de) Semipermeable membran aus polyetherketonen
WO1992011081A1 (fr) Membrane pour la separation de melanges gazeux, procede pour sa fabrication, ainsi que son utilisation
WO1991009669A1 (fr) Membrane composite, son procede de fabrication et son utilisation
DE3421833A1 (de) Membran zur abtrennung von gasen aus gasgemischen und verfahren zu ihrer herstellung
DE2942763A1 (de) Verfahren zur herstellung einer polyacrylnitril-umkehrosmosemembran
DE19511361C1 (de) Verfahren zur Herstellung von Polymermembranen auf der Basis von Polyetheretherketon und ihre Verwendung
EP2292317B1 (fr) Membrane composite
DE19821309C2 (de) Kompositmembran sowie ein Verfahren zu ihrer Herstellung
WO2000074828A1 (fr) Membrane composite pour deshydrater des solutions organiques
DE10326354A1 (de) Trennaktives Kompositmaterial für die Stofftrennung, Kompositmembran, Verwendung und Verfahren zu ihrer Herstellung
DE69822912T2 (de) Verfahren zur Herstellung einer Membran
WO1991009670A1 (fr) Membrane composite, son procede de fabrication et son utilisation
DE10042119B4 (de) Verfahren zur Herstellung von Polymermembranen und Polymermembran
EP0488018A2 (fr) Membrane capillaire de séparation de gaz
DE19902517A1 (de) Verbundmembran, Verfahren zu ihrer Herstellung und Verwendung zur Gastrennung

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU MC NL SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase