DE4231762A1 - Gas separation membrane with improved selectivity and permeability - has separating layer based on inter-penetrating network contg. hairy-rod type polymer and bridged macrocyclic metal complex - Google Patents

Gas separation membrane with improved selectivity and permeability - has separating layer based on inter-penetrating network contg. hairy-rod type polymer and bridged macrocyclic metal complex

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Publication number
DE4231762A1
DE4231762A1 DE19924231762 DE4231762A DE4231762A1 DE 4231762 A1 DE4231762 A1 DE 4231762A1 DE 19924231762 DE19924231762 DE 19924231762 DE 4231762 A DE4231762 A DE 4231762A DE 4231762 A1 DE4231762 A1 DE 4231762A1
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Germany
Prior art keywords
polymers
membrane
hairy
network
gas
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
DE19924231762
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German (de)
Inventor
Hans-Dieter Dr Lehmann
Michael Prof Dr Hanack
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NATURWISSENSCHAFTLICHES und ME
NMI Naturwissenschaftliches und Medizinisches Institut
Original Assignee
NATURWISSENSCHAFTLICHES und ME
NMI Naturwissenschaftliches und Medizinisches Institut
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Priority to DE19924231762 priority Critical patent/DE4231762A1/en
Publication of DE4231762A1 publication Critical patent/DE4231762A1/en
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/22—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by diffusion
    • B01D53/228—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by diffusion characterised by specific membranes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/14—Dynamic membranes
    • B01D69/141—Heterogeneous membranes, e.g. containing dispersed material; Mixed matrix membranes
    • B01D69/142—Heterogeneous membranes, e.g. containing dispersed material; Mixed matrix membranes with "carriers"
    • 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
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
    • C01B13/02—Preparation of oxygen
    • C01B13/0229—Purification or separation processes
    • C01B13/0248—Physical processing only
    • C01B13/0251—Physical processing only by making use of membranes
    • C01B13/0255—Physical processing only by making use of membranes characterised by the type of membrane
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2210/00—Purification or separation of specific gases
    • C01B2210/0043—Impurity removed
    • C01B2210/0046—Nitrogen

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

Abstract

Gas-sepn. membranes (I) are claimed, with separating layers based on a polymer network formed by interpenetration of different polymers with the capacity for self-organisation (II). Pref. at least one of the network polymers (III) is formed in situ during prodn. of the membrane. Pref. network-forming polymers (IIIA) are self-organising hairy-rod polymers The polymers formed in situ (IIIB) are bridged macrocyclic metal complexes, esp. phthalocyanines, naphthocyanines, tetrabenzoporphyrins or tetranaphthoporphyrins, pref. substd. with opt. fluorinated alkyl gps. or alkyl gps. linked to the macrocycle by ether, ketone, ester or amide gps. (to increase solubility), with Fe, Co, Cr, Mn or noble metal as the central atom and with bifunctional electron donors (IV) as bridging gps. USE/ADVANTAGE - Used in unsupported form or supported on flat- or hollow-fibre membranes, for the concn. of one component from a gas mixt., or for sepn. of gas mixts. (claimed). The invention provides gas sepn. membranes with greater selectivity and permeability, based on interpenetrating polymer networks.

Description

Gasmischungen können mit Hilfe von Membranen aus Polymeren getrennt oder ihre Kom­ ponenten zumindestens angereichert werden. Die Wirtschaftlichkeit des Trennprozesses hängt ab von der Selektivität und der Permeabilität der Trennschicht der Membranen. Besonders schwierig ist die Trennung der Bestandteile der Luft, denn Sauerstoff und Stickstoff unter­ scheiden sich nur wenig in ihren Größen und Eigenschaften.Gas mixtures can be separated from polymers with the help of membranes or their com components are at least enriched. The economy of the separation process depends from the selectivity and the permeability of the separation layer of the membranes. Especially It is difficult to separate the components of the air because oxygen and nitrogen are below differ little in their sizes and properties.

In der DE-OS 40 40 363 A1 sowie der darauf basierenden PCT/EP 91/02395 sind zur Gastrennung geeignete Trennschichten aus Polymeren beschrieben, die die Eigenschaft zur Selbstorganisation besitzen. Es handelt sich dabei um Polymere, die ein Polymer-Rückgrat mit einer gewissen Steifigkeit und längerkettige funktionale Seitengruppen besitzen, d. h. Polymere vom sogenannten hairy-rod-Typ. Die technische Aufgabe war es, die Trenn­ schichten aus solchen Polymeren in bezug auf Selektivität und Permeabilität weiter zu verbessern.DE-OS 40 40 363 A1 and the PCT / EP 91/02395 based thereon are known for Gas separation suitable separation layers from polymers described, the property for Own self-organization. These are polymers that have a polymer backbone have a certain stiffness and longer chain functional side groups, d. H. Polymers of the so-called hairy rod type. The technical task was to separate further layer from such polymers in terms of selectivity and permeability improve.

Diese Aufgabe wurde dadurch gelöst, daß interpenetrierende Netzwerke von mindestens zwei Polymeren (I, II usw.) verwendet werden, die zur Selbstorganisation fähig sind. Vorzugs­ weise werden Netzwerke hergestellt dadurch, daß mindestens eines dieser Polymere (I) bei der Membranherstellung in situ entsteht. Seine Bestandteile, die zusammen eine relativ sperrige und steife Polymerkette bilden, werden einzeln in die Lösung der bereits polymer vorliegenden Komponenten (II usw.) in einem geeigneten organischen Lösungsmittel gege­ ben. Beim Verdunsten des Lösungsmittels entsteht ein interpenetrierendes Polymernetzwerk. Das sich dabei neu bildende Polymer I paßt sich darin den durch die hochpolymeren Kom­ ponenten (II usw.) vorgegebenen Raumverhältnissen optimal an. Dadurch wird das für den Gas-Transport zur Verfügung stehende freie Volumen groß und sehr gleichmäßig verteilt. Führt man die Bildung des Polymernetzwerkes auf einem microporösen Träger aus - wie in DE-OS 40 40 363 A1 beschrieben - dann erhält man Kompositmembranen, die zur Gastrennung geeignet sind.This problem was solved in that interpenetrating networks of at least two Polymers (I, II, etc.) are used that are capable of self-assembly. Preferential networks are produced by adding at least one of these polymers (I) membrane production occurs in situ. Its components, which together make up a relative Bulky and rigid polymer chain form, are individually in the solution of the already polymer existing components (II, etc.) in a suitable organic solvent ben. When the solvent evaporates, an interpenetrating polymer network is created. The newly formed polymer I adapts to the high polymer com components (II etc.) to the given spatial conditions. This will make it for the Gas transport available free volumes large and very evenly distributed. If the polymer network is formed on a microporous support - as in DE-OS 40 40 363 A1 described - then you get composite membranes for gas separation are suitable.

Als in situ entstehende Polymere I können mit bifunktionellen Elektronendonatoren über­ brückte makrocyklische Metallkomplexe verwendet werden. Diese sind stapelförmig angeord­ nete makrocyklische Komplexe von Metallen, wie sie aus der Literatur bekannt sind (H. Schulz, H. Lehmann, M. Rein, M. Hanack in: Structure and Bonding 74, J.W. Buchler (Hrsg.), Heidelberg 1991, S. 41) vgl. Abb. 1. As in-situ polymers I can be used with bifunctional electron donors over bridged macrocyclic metal complexes. These are stacked macrocyclic complexes of metals, as are known from the literature (H. Schulz, H. Lehmann, M. Rein, M. Hanack in: Structure and Bonding 74, JW Buchler (ed.), Heidelberg 1991, P. 41) cf. Fig. 1.

Die Makrocyklen tragen vorzugsweise noch Seitengruppen, da dadurch ihre Löslichkeit in organischen Lösungsmitteln verbessert wird.The macrocycles preferably still carry side groups since this makes them soluble in organic solvents is improved.

Als polymer vorliegende Komponenten (II usw.) können alle Makromoleküle dienen, die ein Polymernetzwerk bilden. Bevorzugt werden zur Selbstorganisation fähige Polymere ver­ wendet wie sie beispielsweise in DE-OS 40 40 363 A1 beschrieben sind.All macromolecules containing a can serve as polymeric components (II, etc.) Form polymer network. Polymers capable of self-assembly are preferred applies as described for example in DE-OS 40 40 363 A1.

Als Vergleichsbeispiel nach DE-OS 40 40 363 A1 wurde eine Gas-Trennmembran dadurch hergestellt, daß 0,8% einer mit Acrylnitril modifizierten Hydroxypropylcellulose (AHC vgl. Abb. 2) im THF gelöst wurden. Eine mikroporöse Trägermembran Celgard 2400 wurde in diese Lösung getaucht und anschließend getrocknet (Membran A). Im erfindungsgemäßen Beispiel (Membran B) wurde die Hälfte des Polymers durch ein tertiäre Butylgruppen tragendes Kobalt-Phtalocyanin ersetzt und der Lösung eine dem makrocyklischen Metallkom­ plex äquivalente Menge an Imidazol beigefügt. Die auf den Träger bezogene Gewichts­ zunahme nach der Trocknung betrug bei Membran A 11%, bei Membran B 15,5%.As a comparative example according to DE-OS 40 40 363 A1, a gas separation membrane was produced by dissolving 0.8% of a hydroxypropyl cellulose modified with acrylonitrile (AHC see FIG. 2) in the THF. A microporous Celgard 2400 support membrane was immersed in this solution and then dried (membrane A). In the example according to the invention (membrane B), half of the polymer was replaced by a tertiary butyl group-bearing cobalt phthalocyanine and an amount of the imidazole equivalent to the macrocyclic metal complex was added to the solution. The increase in weight based on the support after drying was 11% for membrane A and 15.5% for membrane B.

Das Ergebnis der Prüfung beider Membranen mit der realen Gasmischung N2:O2 = 80 : 20 bei 50°C ist in Abhängigkeit von der transmembranen Druckdifferenz in Abb. 3 und 4 dargestellt (Kurve O2/N2). Auch die Prüfung der Permeabilität der Membranen mit den Einzelgasen Sauerstoff und Stickstoff ( Kurven O2 und N2 in Abb. 3 und 4) zeigt die Über­ legenheit der erfindungsgemäßen Membran B.The result of testing both membranes with the real gas mixture N 2 : O 2 = 80: 20 at 50 ° C is shown in Fig. 3 and 4 as a function of the transmembrane pressure difference (curve O 2 / N 2 ). Testing the permeability of the membranes with the individual gases oxygen and nitrogen (curves O 2 and N 2 in FIGS. 3 and 4) also shows the superiority of the membrane B according to the invention.

Die Sauerstoffanreicherung lag im Vergleichsbeispiel (Membran A) durchweg zwischen 32 und 33% O2 im Permeat, die für Membran B hingegen zwischen 36 und 38%. Dies zeigt, daß überraschenderweise sowohl die Selektivität als auch die Permeabilität der erfindungs­ gemäßen Membran B besser sind als im Vergleichsbeispiel. Erfahrungsgemäß sind sonst Selektivität und Permeabilität miteinander invers gekoppelt, d. h. bei höherer Permeabilität geht die Selektivität zurück.In the comparative example (membrane A), the oxygen enrichment was consistently between 32 and 33% O 2 in the permeate, that for membrane B, however, was between 36 and 38%. This shows that, surprisingly, both the selectivity and the permeability of the membrane B according to the invention are better than in the comparative example. Experience has shown that selectivity and permeability are otherwise inversely coupled, ie the selectivity declines with higher permeability.

Das Beispiel soll die Erfindung erläutern, aber nicht einschränken. Für die beschriebene Trennaufgabe zur Anreicherung von O2 aus Luft wird beispielsweise vorteilhaft mit Polymernetzwerken gearbeitet, welche fluorhaltige Gruppen besitzen. Dadurch läßt sich bekanntlich die Löslichkeit von Sauerstoff in der Trennschicht erhöhen und die Effizienz der Abtrennung verbessern. Die Beschreibung der Erfindung am besonders schwer zu trennenden Gasgemisch N2 : O2 soll die Anwendung der erfindungsgemäßen Membranen nicht auf dieses Trennproblem einschränken.The example is intended to illustrate, but not to limit, the invention. For the separation task described for the enrichment of O 2 from air, it is advantageous, for example, to work with polymer networks which have fluorine-containing groups. As is known, this can increase the solubility of oxygen in the separation layer and improve the efficiency of the separation. The description of the invention in the gas mixture N 2 : O 2 , which is particularly difficult to separate, is not intended to restrict the use of the membranes according to the invention to this separation problem.

Claims (7)

1. Zur Gastrennung geeignete Membran mit Trennschicht aus einem Polymer-Netzwerk, dadurch gekennzeichnet, daß sich verschiedene Polymere mit der Fähigkeit zur Selbst­ organisation gegenseitig durchdringen.1. Suitable for gas separation membrane with a separating layer of a polymer network, characterized in that different polymers with the ability to self-organization penetrate each other. 2. Membran und Trennschicht nach Anspruch 1, dadurch gekennzeichnet, daß im Netzwerk aus verschiedenen Polymeren mindestens ein Polymer sich erst bei der Membranher­ stellung in situ bildet.2. Membrane and separation layer according to claim 1, characterized in that in the network from different polymers at least one polymer is only found in the membrane position in situ. 3. Membran und Trennschicht nach Anspruch 1 und 2, dadurch gekennzeichnet, daß als netzwerkbildende Polymere solche vom hairy-rod-Typ verwendet werden.3. membrane and separation layer according to claim 1 and 2, characterized in that as network-forming polymers of the hairy-rod type are used. 4. Membran und Trennschicht nach Anspruch 1 bis 3, dadurch gekennzeichnet, daß als zur Selbstorganisation fähige Polymere solche vom hairy-rod-Typ verwendet werden, wie sie in DE-OS 40 40 363 A1 und PCT/EP 91/02395 beschrieben sind.4. membrane and separation layer according to claim 1 to 3, characterized in that as for Self-assembling capable polymers such as the hairy rod type are used as they are are described in DE-OS 40 40 363 A1 and PCT / EP 91/02395. 5. Membran und Trennschicht nach Anspruch 1 und 2, dadurch gekennzeichnet, daß als in situ entstehende Polymere überbrückte makrocyclische Metall-Komplexe verwendet werden.5. membrane and separation layer according to claim 1 and 2, characterized in that as in In-situ polymers used bridged macrocyclic metal complexes become. 6. Membran und Trennschicht nach Anspruch 1 bis 3, dadurch gekennzeichnet, daß hairy­ rod-artige Polymere und makrocyklische Metallkomplexe in einer Lösung zusammen mit bifunktionalen Elektronendonatoren zur Herstellung von Trennschichten verwendet werden.
ie Makrocyklen können aus den Klassen der Phthalocyanine, Naphthocyanine und Tetrabenzoporphyrine, Tetranaphtoporphyrine ausgewählt sein und tragen zur Verbes­ serung ihrer Löslichkeit Substituenten.
Als Substituenten kommen in Betracht Alkylreste oder solche, die über Äther-, Keton-, Ester- oder Säureamidfunktionen an die Makrocyklen gebunden sind. Die Substituenten können auch fluoriert sein. Als zentrale Metallatome können Fe, Co, Cr, Mn oder edlere Metalle dienen. Als Brücken dienen bifunktionelle Elektronen-Donatoren.6. membrane and separating layer according to claim 1 to 3, characterized in that hairy rod-like polymers and macrocyclic metal complexes are used in a solution together with bifunctional electron donors for the production of separating layers.
The macrocycles can be selected from the classes of phthalocyanines, naphthocyanines and tetrabenzoporphyrins, tetranaphtoporphyrins and contribute to the improvement of their solubility.
Possible substituents are alkyl radicals or those which are bonded to the macrocycles via ether, ketone, ester or acid amide functions. The substituents can also be fluorinated. Fe, Co, Cr, Mn or more noble metals can serve as central metal atoms. Bifunctional electron donors serve as bridges. 7. Verwendung der Membran nach Anspruch 1 bis 6 - mit oder ohne Träger in Form von Flach- oder Hohlfasermembranen - für die Anreicherung von einer Komponente aus Gasmischungen oder zu deren Trennung.7. Use of the membrane according to claim 1 to 6 - with or without a carrier in the form of Flat or hollow fiber membranes - for enrichment from one component Gas mixtures or for their separation.
DE19924231762 1992-09-23 1992-09-23 Gas separation membrane with improved selectivity and permeability - has separating layer based on inter-penetrating network contg. hairy-rod type polymer and bridged macrocyclic metal complex Withdrawn DE4231762A1 (en)

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DE19924231762 DE4231762A1 (en) 1992-09-23 1992-09-23 Gas separation membrane with improved selectivity and permeability - has separating layer based on inter-penetrating network contg. hairy-rod type polymer and bridged macrocyclic metal complex

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DE19924231762 DE4231762A1 (en) 1992-09-23 1992-09-23 Gas separation membrane with improved selectivity and permeability - has separating layer based on inter-penetrating network contg. hairy-rod type polymer and bridged macrocyclic metal complex

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1418207A1 (en) * 2002-11-08 2004-05-12 Orient Chemical Industries, Ltd. Mu-oxo bridged heterometal compound and selective production method thereof

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4120919A1 (en) * 1990-08-22 1992-03-05 Geesthacht Gkss Forschung Membranes, esp. for gas sepn. and pervaporation - comprise crosslinked films based on copolymers of N-substd.-maleimide(s) and vinyl¨ ether(s)¨, on a suitable support
DE4029808A1 (en) * 1990-09-20 1992-03-26 Bayer Ag Segmented aromatic polycarbonate(s) for gas sepn. membranes - contg. aromatic carbonate¨ of 1,1-bis-4-hydroxyphenyl-cycloalkane(s), and hydrogenated dimer fatty acid polyester for sealing

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4120919A1 (en) * 1990-08-22 1992-03-05 Geesthacht Gkss Forschung Membranes, esp. for gas sepn. and pervaporation - comprise crosslinked films based on copolymers of N-substd.-maleimide(s) and vinyl¨ ether(s)¨, on a suitable support
DE4029808A1 (en) * 1990-09-20 1992-03-26 Bayer Ag Segmented aromatic polycarbonate(s) for gas sepn. membranes - contg. aromatic carbonate¨ of 1,1-bis-4-hydroxyphenyl-cycloalkane(s), and hydrogenated dimer fatty acid polyester for sealing

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1418207A1 (en) * 2002-11-08 2004-05-12 Orient Chemical Industries, Ltd. Mu-oxo bridged heterometal compound and selective production method thereof
US7087747B2 (en) 2002-11-08 2006-08-08 Orient Chemical Industries, Ltd. μ-Oxo bridged heterometal compound and selective production method thereof

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