EP0193861A2 - Carbon monoxide breathing air filter - Google Patents

Carbon monoxide breathing air filter Download PDF

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Publication number
EP0193861A2
EP0193861A2 EP86102494A EP86102494A EP0193861A2 EP 0193861 A2 EP0193861 A2 EP 0193861A2 EP 86102494 A EP86102494 A EP 86102494A EP 86102494 A EP86102494 A EP 86102494A EP 0193861 A2 EP0193861 A2 EP 0193861A2
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EP
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Prior art keywords
catalyst
air filter
breathing air
filter layer
metal
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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Withdrawn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
EP86102494A
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German (de)
French (fr)
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EP0193861A3 (en
Inventor
Carl-Ernst Dr. Van Der Smissen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Draegerwerk AG and Co KGaA
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Draegerwerk AG and Co KGaA
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Application filed by Draegerwerk AG and Co KGaA filed Critical Draegerwerk AG and Co KGaA
Publication of EP0193861A2 publication Critical patent/EP0193861A2/en
Publication of EP0193861A3 publication Critical patent/EP0193861A3/en
Withdrawn legal-status Critical Current

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    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
    • A62B19/00—Cartridges with absorbing substances for respiratory apparatus
    • A62B19/02—Cartridges with absorbing substances for respiratory apparatus with oxidising agents

Definitions

  • the invention relates to a carbon oxide breathing air filter with a first filter layer through which at least one-way breathing flows and which contains a first CO catalyst.
  • a carbon oxide breathing air filter intended for one-way breathing is known, which as an oxidizing catalyst hopkalite, i.e. contains a mixture of copper oxide and manganese dioxide, as well as other filter materials to protect the catalyst against moisture.
  • This catalyst can oxidize high CO concentrations to harmless CO 2 and shows only a slow decrease in the catalyst effect during its possible service life in the dry state.
  • the moisture sensitivity of the hopkalite catalyst poses a particular risk of use because the respective water vapor loading condition cannot be determined with certainty after use of the filter for a long time before use.
  • Precious metals in particular metals from the group of platinum metals on a porous carrier made of activated carbon or proteins, are also known as catalysts for carbon oxide breathing air filters (publication by the American Society of Mechanical Engineers, ASME 77 ENAs-28, 1957.5).
  • Precious metal catalysts of this type achieve a sufficient protective effect only after a certain formation time when high CO concentrations are rapidly flooded, but are considerably less sensitive to the influence of water vapor than hopkalite.
  • the invention is based on the task of developing a carbon oxide breathing air filter of the type specified at the outset in such a way that a relatively long service life is achieved when used immediately under high CO concentrations and high atmospheric humidity.
  • the first filter layer is combined with a second filter layer which contains a second CO catalyst, the catalyst action and water vapor sensitivity of which differ from that of the first CO catalyst is.
  • a CO catalyst that allows high CO concentrations right from the start, but loses its activity after a relatively short time under the influence of atmospheric humidity, can be combined with another CO catalyst that only takes a certain time to act achieves a sufficient filter effect, but then maintains its activity for a long time even under high humidity.
  • the first CO catalyst can expediently contain at least one metal or a metal compound from the group of noble metals, while the second CO catalyst upstream of the inhaled air contains oxides of base metals.
  • the second CO catalyst oxidizes only a small amount of CO after a long period of operation, it is ensured that no dangerous CO concentrations occur behind the first catalyst, since the activity of the first catalyst increases at least to the same extent as the activity of the second catalyst decreases.
  • the first CO catalyst is a metal or a metal compound from the group of platinum metals applied to a support
  • the second CO catalyst contains a mixture of copper oxide and a manganese oxide, preferably hopkalite.
  • a metal from the group of platinum metals such as platinum, palladium, rhodium or ruthenium, is used in the first catalyst, either elementarily, as an oxide or as a salt, for example as a chloride.
  • This metal or the metal compound can advantageously on a granulated, porous carrier made of activated carbon, active alumina, silica gel, zeolite or plastic fiber material, optionally using metallic or oxidic underlayers.
  • the combination of the noble metal catalyst, which contains at least one metal from the group of platinum metals on a corresponding support, with a hopkalite catalyst connected upstream in the direction of flow of the inhaled air results in a respiratory air filter which has a relatively long service life under high impact and continuous loads.
  • the combination effect of both catalysts can be explained by the fact that the platinum catalyst forms carbonyl on its surface under the action of CO. This can be reacted with oxygen and broken down as long as the surface of the catalyst is only partially covered with carbonyl and further oxygen access is possible. A high carbon concentration immediately forms a coherent carbonyl layer that is difficult to break open and blocks the catalytic effect.
  • the upstream hopkalite catalyst prevents high CO concentrations from striking directly onto the platinum catalyst, so that the carbonyl layer can expand in the depth of the support, leaving the pores that allow oxygen access free.
  • the platinum catalytic converter is offered the possibility of uniform formation, which enables the unfolding the long-lasting catalyst effect guaranteed.
  • the breathing air filter described can be used both in one-way operation, with valve exhalation, and in pendulum breathing.
  • One-way breathing delays the harmful water vapor loading of the hopkalite catalyst.
  • the breathing air filter consists of a filter housing 1 in which a first filter layer 2 with a platinum metal catalyst is accommodated between holding surfaces 3 with low flow resistance.
  • the platinum metal catalyst is e.g. made of granular aluminum oxide with an occupancy of 0.5% palladium.
  • a second filter layer 4 is provided upstream of the inhaled air and contains granulated hopkalite as the second CO catalyst.
  • An air-permeable cover 5 closes the filter housing 1.

Abstract

The filter having a first filter layer which carries a flow at least in one-way breathing and contains a first CO catalyst, is to be improved with respect to its protective action at high CO concentration and during long periods in use. According to the invention, this is achieved by combining the first filter layer (2) with a second filter layer (4) which contains a second CO catalyst whose catalyst activity and water vapour sensitivity differs from those of the first CO catalyst. In a favourable combination, the first CO catalyst contains a metal or metal compound from the group of the platinum metals applied to a support, and the second CO catalyst contains hopcalite. <IMAGE>

Description

Die Erfindung betrifft einen Kohlenoxid-Atemluftfilter mit einer wenigstens in Einwegatmung durchströmten ersten Filterschicht, welche einen ersten CO-Katalysator enthält.The invention relates to a carbon oxide breathing air filter with a first filter layer through which at least one-way breathing flows and which contains a first CO catalyst.

Aus der DE-PS 12 46 416 ist ein für Einwegatmung bestimmtes Kohlenoxid-Atemluftfilter bekannt, welches als oxidierenden Katalysator Hopkalit, d.h. eine Mischung von Kupferoxid und Mangandioxid, sowie weitere Filtermaterialien zum Schutz des Katalysators gegen Feuchtigkeit enthält.From DE-PS 12 46 416 a carbon oxide breathing air filter intended for one-way breathing is known, which as an oxidizing catalyst hopkalite, i.e. contains a mixture of copper oxide and manganese dioxide, as well as other filter materials to protect the catalyst against moisture.

Dieser Katalysator kann hohe CO-Konzentrationen zu unschädlichem C02 oxidieren und zeigt während seiner möglichen Gebrauchsdauer in trockenem Zustand nur einen langsamen Abfall der Katalysatorwirkung. Die Feuchtigkeitsempfindlichkeit des Hopkalit-Katalysators bedingt aber ein besonderes Einsatzrisiko, weil sich der jeweilige Wasserdampf-Beladungszustand nach längerer Lagerdauer des Filters vor Gebrauch nicht mit Sicherheit feststellen läßt.This catalyst can oxidize high CO concentrations to harmless CO 2 and shows only a slow decrease in the catalyst effect during its possible service life in the dry state. The moisture sensitivity of the hopkalite catalyst, however, poses a particular risk of use because the respective water vapor loading condition cannot be determined with certainty after use of the filter for a long time before use.

Als Katalysatoren für Kohlenoxid-Atemluftfilter sind ferner Edelmetalle, insbesondere Metalle aus der Gruppe der Platinmetalle auf einem porösen Träger aus Aktivkohle oder Eiweißstoffen, bekannt (Veröffentlichung der American Society of Mechanical Engineers, ASME 77 ENAs-28, 1957,5). Derartige Edelmetallkatalysatoren erreichen beim raschen Anfluten hoher CO-Konzentrationen erst nach einer gewissen Formierungszeit eine ausreichende Schutzwirkung, sind jedoch gegen den Einfluß von Wasserdampf wesentlich unempfindlicher als Hopkalit.Precious metals, in particular metals from the group of platinum metals on a porous carrier made of activated carbon or proteins, are also known as catalysts for carbon oxide breathing air filters (publication by the American Society of Mechanical Engineers, ASME 77 ENAs-28, 1957.5). Precious metal catalysts of this type achieve a sufficient protective effect only after a certain formation time when high CO concentrations are rapidly flooded, but are considerably less sensitive to the influence of water vapor than hopkalite.

Die Erfindung geht von der Aufgabenstellung aus, ein Kohlenoxid-Atemluftfilter der eingangs angegebenen Art so weiterzubilden, daß beim Soforteinsatz unter hohen CO-Konzentrationen und hoher Luftfeuchte eine relativ lange Gebrauchsdauer erreicht wird.The invention is based on the task of developing a carbon oxide breathing air filter of the type specified at the outset in such a way that a relatively long service life is achieved when used immediately under high CO concentrations and high atmospheric humidity.

Die Lösung dieser Aufgabenstellung erfolgt dadurch, daß die erste Filterschicht mit einer zweiten Filterschicht kombiniert ist, welche einen zweiten CO-Katalysator enthält, dessen Katalysatorwirkung und Wasserdampfempfindlichkeit unterschiedlich von der des ersten CO-Katalysators ist. Auf diese Weise läßt sich ein CO-Katalysator, welcher bereits von Anfang an hohe CO-Konzentrationen zuläßt, aber schon nach relativ kurzer Zeit unter dem Einfluß der Luftfeuchte seine Aktivität verliert, mit einem weiteren CO-Katalysator kombinieren, der erst nach einer gewissen Einwirkungszeit eine ausreichende Filterwirkung erzielt, aber dann auch unter hoher Luftfeuchtigkeit seine Aktivität für lange Zeit beibehält.This object is achieved in that the first filter layer is combined with a second filter layer which contains a second CO catalyst, the catalyst action and water vapor sensitivity of which differ from that of the first CO catalyst is. In this way, a CO catalyst that allows high CO concentrations right from the start, but loses its activity after a relatively short time under the influence of atmospheric humidity, can be combined with another CO catalyst that only takes a certain time to act achieves a sufficient filter effect, but then maintains its activity for a long time even under high humidity.

Der erste CO-Katalysator kann dabei zweckmäßig wenigstens ein Metall bzw. eine Metallverbindung aus der Gruppe der Edelmetalle enthalten, während der zweite in Strömungsrichtung der Einatemluft vorgeschaltete CO-Katalysator Oxide von unedlen Metallen enthält. Obwohl der zweite CO-Katalysator nach längerer Betriebsdauer hohe CO-Konzentrationen nur noch in geringem Umfang oxidiert, ist sichergestellt, daß hinter dem ersten Katalysator keine gefährlichen CO-Konzentrationen auftreten, da die Aktivität des ersten Katalysators mindestens in dem Maße zunimmt, wie die Aktivität des zweiten Katalysators abnimmt.The first CO catalyst can expediently contain at least one metal or a metal compound from the group of noble metals, while the second CO catalyst upstream of the inhaled air contains oxides of base metals. Although the second CO catalyst oxidizes only a small amount of CO after a long period of operation, it is ensured that no dangerous CO concentrations occur behind the first catalyst, since the activity of the first catalyst increases at least to the same extent as the activity of the second catalyst decreases.

Eine erprobte günstige Kombination kann vorsehen, daß der erste CO-Katalysator ein auf einem Träger aufgebrachtes Metall bzw. eine Metallverbindung aus der Gruppe der Platinmetalle ist, und daß der zweite CO-Katalysator ein Gemisch aus Kupferoxid und einem Manganoxid, vorzugsweise Hopkalit enthält. Bei einem solchen Atemluftfilter wird im ersten Katalysator ein Metall aus der Gruppe der Platinmetalle, wie Platin, Palladium, Rhodium oder Ruthenium, entweder elementar, als Oxid oder auch als Salz, z.B. als Chlorid verwendet. Dieses Metall bzw. die Metallverbindung kann vorteilhaft auf einem granulierten, porösen Träger aus Aktivkohle, aktiver Tonerde, Kieselgel, Zeolith oder Kunststoffasermaterial, gegebenenfalls unter Verwendung von metallenen oder oxidischen Unterlagschichten aufgebracht werden.A tried-and-tested, favorable combination can provide that the first CO catalyst is a metal or a metal compound from the group of platinum metals applied to a support, and that the second CO catalyst contains a mixture of copper oxide and a manganese oxide, preferably hopkalite. In such a breathing air filter, a metal from the group of platinum metals, such as platinum, palladium, rhodium or ruthenium, is used in the first catalyst, either elementarily, as an oxide or as a salt, for example as a chloride. This metal or the metal compound can advantageously on a granulated, porous carrier made of activated carbon, active alumina, silica gel, zeolite or plastic fiber material, optionally using metallic or oxidic underlayers.

Die Kombination des Edelmetall-Katalysators, welcher mindestens ein Metall aus der Gruppe der Platinmetalle auf einem entsprechenden Träger enthält, mit einem in Strömungsrichtung der Einatemluft vorgeschalteten Hopkalit-Katalysator ergibt ein Atemluftfilter, welches bei hoher Stoß- und Dauerbelastung eine relativ lange Gebrauchsdauer aufweist.The combination of the noble metal catalyst, which contains at least one metal from the group of platinum metals on a corresponding support, with a hopkalite catalyst connected upstream in the direction of flow of the inhaled air results in a respiratory air filter which has a relatively long service life under high impact and continuous loads.

Die Kombinationswirkung beider Katalysatoren ist dadurch erklärbar, daß der Platin-Katalysator unter CO-Einwirkung an seiner Oberfläche Carbonyl bildet. Dieses kann mit Sauerstoff so lange umgesetzt und abgebaut werden, wie die Oberfläche des Katalysators nur teilweise mit Carbonyl überzogen und dadurch weiterer Sauerstoffzutritt möglich ist. Bei Stoßbelastung mit hohen Konzentrationen bildet sich sofort eine zusammenhängende Carbonylschicht, die schwer aufzubrechen ist und die Katalysatorwirkung blockiert. Durch den vorgeschalteten Hopkalit-Katalysator wird verhindert, daß hohe CO-Konzentrationen unmittelbar auf den Platin-Katalysator durchschlagen, so daß sich die Carbonylschicht unter Freilassung von den Sauerstoffzutritt ermöglichenden Poren in der Tiefe des Trägers ausbreiten kann.The combination effect of both catalysts can be explained by the fact that the platinum catalyst forms carbonyl on its surface under the action of CO. This can be reacted with oxygen and broken down as long as the surface of the catalyst is only partially covered with carbonyl and further oxygen access is possible. A high carbon concentration immediately forms a coherent carbonyl layer that is difficult to break open and blocks the catalytic effect. The upstream hopkalite catalyst prevents high CO concentrations from striking directly onto the platinum catalyst, so that the carbonyl layer can expand in the depth of the support, leaving the pores that allow oxygen access free.

Durch die Vorschaltung des Hopkalyt-Katalysators wird somit dem Platin-Katalysator die Möglichkeit einer gleichmäßigen Formierung geboten, welche die Entfaltung der lang dauernden Katalysatorwirkung gewährleistet.By connecting the hop catalytic converter upstream, the platinum catalytic converter is offered the possibility of uniform formation, which enables the unfolding the long-lasting catalyst effect guaranteed.

Das beschriebene Atemluftfilter kann sowohl in Einwegbetrieb, mit Ventilausatmung, als auch in Pendelatmung benutzt werden. Durch Einwegatmung wird die schädliche Wasserdampfbeladung des Hopkalit-Katalysators hinausgezögert.The breathing air filter described can be used both in one-way operation, with valve exhalation, and in pendulum breathing. One-way breathing delays the harmful water vapor loading of the hopkalite catalyst.

In der Zeichnung ist ein Ausführungsbeispiel eines Atemluftfilters gemäß der Erfindung schematisch dargestellt.In the drawing, an embodiment of a breathing air filter according to the invention is shown schematically.

Das Atemluftfilter besteht aus einem Filtergehäuse 1, in dem eine erste Filterschicht 2 mit einem Platinmetall-Katalysator zwischen Halteflächen 3 mit geringem Strömungswiderstand untergebracht ist. Der Platinmetall-Katalysator besteht z.B. aus körnigem Aluminiumoxid mit einer Belegung von 0,5 % Palladium.The breathing air filter consists of a filter housing 1 in which a first filter layer 2 with a platinum metal catalyst is accommodated between holding surfaces 3 with low flow resistance. The platinum metal catalyst is e.g. made of granular aluminum oxide with an occupancy of 0.5% palladium.

In Strömungsrichtung der Einatemluft vorgeschaltet ist eine zweite Filterschicht 4 vorgesehen, welche granuliertes Hopkalit als zweiten CO-Katalysator enthält. Ein luftdurchlässiger Deckel 5 schließt das Filtergehäuse 1 ab.A second filter layer 4 is provided upstream of the inhaled air and contains granulated hopkalite as the second CO catalyst. An air-permeable cover 5 closes the filter housing 1.

Claims (4)

1. Kohlenoxid-Atemluftfilter mit einer wenigstens in Einwegatmung durchströmten ersten Filterschicht, welche einen ersten CO-Katalysator enthält, dadurch gekennzeichnet, daß die erste Filterschicht (2) mit einer zweiten Filterschicht (4) kombiniert ist, welche einen zweiten CO-Katalysator enthält, dessen Katalysatorwirkung und Wasserdampfempfindlichkeit unterschiedlich von der des ersten CO-Katalysators ist.1. A carbon oxide breathing air filter with a first filter layer which contains at least one-way breathing and which contains a first CO catalyst, characterized in that the first filter layer (2) is combined with a second filter layer (4) which contains a second CO catalyst, whose catalyst action and water vapor sensitivity is different from that of the first CO catalyst. 2. Atemluftfilter nach Anspruch 1, dadurch gekennzeichnet, daß der erste CO-Katalysator wenigstens ein metall bzw. eine Metallverbindung aus der Gruppe der Edelmetalle enthält, und daß der zweite in Strömungsrichtung der Einatemluft vorgeschaltete CO-Katalysator Oxide von unedlen Metallen enthält.2. Breathing air filter according to claim 1, characterized in that the first CO catalyst contains at least one metal or a metal compound from the group of noble metals, and that the second CO catalyst upstream in the direction of flow of the inhaled air contains oxides of base metals. 3. Atemluftfilter nach Anspruch 2, dadurch gekennzeichnet, daß der erste CO-Katalysator ein auf einem Träger aufgebrachtes Metall bzw. eine Metallverbindung aus der Gruppe der Platinmetalle, und der zweite CO-Katalysator ein Gemisch aus Kupferoxid und einem Manganoxid enthält.3. Breathing air filter according to claim 2, characterized in that the first CO catalyst is a metal applied to a carrier or a metal compound from the group of the platinum metals, and the second CO catalyst contains a mixture of copper oxide and a manganese oxide. 4. Atemluftfilter nach Anspruch 3, dadurch gekennzeichnet, daß der zweite CO-Katalysator Hopkalit enthält.4. Breathing air filter according to claim 3, characterized in that the second CO catalyst contains hopkalite.
EP86102494A 1985-03-02 1986-02-26 Carbon monoxide breathing air filter Withdrawn EP0193861A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853507486 DE3507486A1 (en) 1985-03-02 1985-03-02 CARBON OXIDE BREATHING AIR FILTER
DE3507486 1985-03-02

Publications (2)

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EP0193861A2 true EP0193861A2 (en) 1986-09-10
EP0193861A3 EP0193861A3 (en) 1989-02-22

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EP86102494A Withdrawn EP0193861A3 (en) 1985-03-02 1986-02-26 Carbon monoxide breathing air filter

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JP (1) JPS61209674A (en)
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995007115A1 (en) * 1993-09-08 1995-03-16 Coal Industry (Patents) Limited Improvements in or relating to respiratory protective equipment

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3719420A1 (en) * 1987-06-11 1988-12-29 Sandler Helmut Helsa Werke RESPIRATORY MASK
DE4014518A1 (en) * 1990-05-07 1991-11-14 Hoelter Heinz Multi-layer dust filer - has anti-bactericide and -fungicide action for allergy sufferer, using active metal filter
TW287952B (en) * 1994-08-31 1996-10-11 Lifepro Inc
US5964218A (en) * 1994-08-31 1999-10-12 Lifepro, Inc. Face mask with back-up smoke inhalation protection and method of operation
US5690101A (en) * 1995-07-14 1997-11-25 Kutta; Helmuth W. Portable air purifier with chemical reaction zone
KR101332199B1 (en) * 2012-06-21 2013-11-25 주식회사 이엠따블유에너지 Portable air purifier

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE671176C (en) * 1934-12-06 1939-02-11 Auergesellschaft Akt Ges Respiratory protection filter against carbon oxide
DE1246416B (en) * 1965-05-17 1967-08-03 Draegerwerk Ag Carbon monoxide filter self-rescuer
EP0155991A1 (en) * 1984-02-14 1985-10-02 Drägerwerk Aktiengesellschaft Carbon monoxide respiratory apparatus

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57195475A (en) * 1981-05-28 1982-12-01 Matsushita Electric Ind Co Ltd Gas mask

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE671176C (en) * 1934-12-06 1939-02-11 Auergesellschaft Akt Ges Respiratory protection filter against carbon oxide
DE1246416B (en) * 1965-05-17 1967-08-03 Draegerwerk Ag Carbon monoxide filter self-rescuer
EP0155991A1 (en) * 1984-02-14 1985-10-02 Drägerwerk Aktiengesellschaft Carbon monoxide respiratory apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995007115A1 (en) * 1993-09-08 1995-03-16 Coal Industry (Patents) Limited Improvements in or relating to respiratory protective equipment

Also Published As

Publication number Publication date
JPS61209674A (en) 1986-09-17
EP0193861A3 (en) 1989-02-22
DE3507486A1 (en) 1986-09-04
DE3507486C2 (en) 1987-01-02

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