MXPA96006199A

MXPA96006199A - Procedure and filter for preparation of non-free nitrogen monoxide using polymers quecontain azu

Info

Publication number: MXPA96006199A
Application number: MXPA/A/1996/006199A
Authority: MX
Inventors: Schleicher Andreas; Frank Georg; Eschwey Manfred; Von Eysmondt Jorg; Stresius Hanns
Original assignee: Hoechst Ag 65929 Frankfurt De
Priority date: 1994-07-07
Filing date: 1996-12-06
Publication date: 1998-02-01

Abstract

A process and filter for the production of NO2-free nitrogen monoxide based on placing a gas or liquid containing NO2 in contact with a sulfur-containing polymer material, for example poly (arylene thioether), in particular, polyphenylene sulfide The procedure or filter is suitable for the generation of nitrogen monoxide-nitrogen-air mixtures, NOz-free for medical applications

Description

PROCEDURE AND FUTRO PRR PREPARATION OF MONOXIDE E NITROGEN FREE OF NO- USING POLYMERS CONTAINING SULFUR.

The invention relates to a process for the preparation of gases and liquids free of nitrogen dioxide and a filter for the selective elimination of nitrogen dioxide from gases and liquids. , * Nitrogen oxide gas or gae mixtures of nitrogen monoxide that are free of nitrogen dioxide are required in discharge gas metrology for measurement calibration and analysis systems. Recently, the medical use of nitrogen monoxide (NO) has had particular importance. The addition of NO to the breathing air in patients who have pulmonary sinus symptoms, may decrease blood hypertension in the , * «* Pulmonary circulation. In combination with the bronchodilator action of NO, improved aeration of various sections of the lung occurs, and therefore improved gas exchange. The colorless nitrogen monoxide (NO) reacts rapidly with olecular oxygen to form nitrogen dioxide (NOa). Therefore, N02 is formed in the presence of air or by the admission of air, from NO. The N0a (due to omnipresent oxygen) is, therefore, an inherent impurity of NO. Due to its toxicity, the NOa content should be very low, especially in the case of a medical use of NO. Therefore, there have been attempts to selectively absorb or convert NO to Na, once formed. The catalytic conversion of N0a to NO in the presence of oxygen is possible according to: 2 NO 2 NO + 02 i 2 T ^ in a Cu, Mo or Ni catalyst at temperatures higher than 220, C. This method is used in the separate determination of NO and NOs, with the quirmli niscence method (see operation and maintenance instructions for the measuring instrument of No? CSI 1600 of Columbia Scientific Industries, Oust ± n, Texas, 1980). Disadvantages in this procedure are the aH at the required temperature and the possibility of recombination of NO + / ¿? to give NO »after cooling the gas stream. It is also known that the NOs. it dissolves very rapidly in concentrated inorganic acids such as HN03 or H2O. Therefore NO can be easily purified by the aforementioned acids using a gas scrubber (fl Golloch, flnorgam sch-cheini sche Praparate [Preparations for Inorganic Chemistry], Ualter de Gruyter Verlaf 1985, pp. 232 ff.) A disadvantage in this case is the relatively high cost in terms of safety engineering and chemistry. Additional methods are condensation and distillation t / driven to eliminate O ^ of NO. A summary presentation of the purification procedures for NO is found in: G. Brauer, Handbuch der praparativen anorganischenrn Chemie [Manual of Preparative Inorganic Chemistry], vol. 1, p. 470 ff. , 3a. ed. (1975), Verlag. F. Fnl - e. The object is to find a simple procedure and filter for the selective elimination of NOs »from liquids or gases containing N0, < . r "* •" - It has been shown that a selective removal of NOa from NO, or means containing NO such as gases or liquids, can be carried out in a highly efficient manner by contacting them with a sulfur-containing polymer, preferably polyalkylene oxide), in particular poly (femlene sulphide). Therefore, the invention relates to a process for the preparation of gases or liquids that '"They contain NO that are free of O ^, which comprises contacting a gas containing NO" or a liquid containing NO,., With a material that contains a polymer with sulfur; the NOs »is eliminated preferably from a gaseous mixture containing NO. The Lon Express "free of NOa" means that the content of NOs »in a medium is less than 1 pp. DO NOT? it is used as a collective term for nitrogen oxides NO, NOs »and Nc.0 and also includes mixtures of these 0x1 two.

Sulfur-containing polymers are, for example, p > linear or branched olipelago (average molecular weight, MW: 4000-200, 000) having the repeating unit of formula I containing at least one thioether group, - [(flr) n ~ X] m-r (flr52) t.-Ylj - [(Ar3) 1 < -Z] 1 .- [(flr'v) 0 -?] P > - (I) where Ar1, Ar52, Ar3, Ar *, U, X, Y, and Z are identical or independent of each other The indices n, in, i, j,, 1, o and p are integers from 0 to 4, where their sum must be at least 2. Ar3-, Ar2, Ara, and Ar * are in the formula I simple aryl systems or directly joined in para-, meta-,? Ortho-, which have from 6 to 18 carbon atoms, Ul, X, Y, and Z, are linking groups, selected from the group consisting of -S0a-, ~ S-, -SO-, -0-. ~ C0-, -COs »-, alkyl and alkylidene groups having from 1 to 6 carbon atoms and -NR 11 - groups, wherein ** 3 is alkyl, or alkyl Ldene groups having 6 carbon atoms The aryl systems of formula I, in the context of the invention, depending on its chemical structure, may additionally contain, independently, one or more usual functional groups, for example alkyl radicals, halogens, sulphonic acid, arnino, nitro, cyano, hydroxyl or carboxyl groups You can also n be used with block polymers of units of formula I. The interaction of sulfur-containing polymers such as co or pol? (apolyoether) with NO is negligibly small in comparison to the interaction with NOs ", therefore the separation of Os is possible from a gas stream containing NO *. Preferred sulfur-containing polymers are polyaryaniines having repeating units of the formulas (II-VI) whose synthesis is described for example in Chimia 28 (9), 567: and poly (thioethers of arylenes) having repeating units of formula VII which are described for example in US-A-4, 016, 145.

Particularly preferred sulfur-containing polymers are femlene polysulphides (PPS) having the repeated form of formula VIII, the preparation process of which is described, for example, in patent documents US 3,919,177, US 4,038,262 and US 4,282,247 .

- * "The PPS of the formula VIII can also have a content of up to 50 mole percent of a 1,2- and / or 1,3- union in the aromatic nucleus, the PPS are considered to be both linear material and In addition, the PPS of the formula VIII may contain, per unit, independently of each other, 4 functional groups, for example alkyl radicals, halogens, sulphonic acid, hydroxyl groups, amine, nitro, cyano or carboxyl. If polycarbonates are used according to the invention, it is generally appropriate that the apolipoprotein +) have an average molecular weight of 4000 to 200,000, preferably 10,000 to 150,000, in particular 25,000 to 100,000. (determined by gel penetration chromatography.) Sulfur containing polymers can be used as a powder, fiber, nonwoven web, woven fabric, film, concreted material, molded or as a coating or impregnation of support materials. which have a particularly large surface area, can be produced by suitable methods to have for example a honeycomb structure or grid. The powders have, for example, commercial particle sizes, the granules also being usable. It is important in this case that the gas or liquid to be treated can pass unobstructed through the polymeric material, for example in the form of a fixed bed of powder. If polymers are used as fibers, they are used 'Orno short fibers, felt needle, non-woven material, carded tape or woven fabric. Films or film fragments can also be used in a suitable manner. Coatings or support materials with sulfur-containing polymer such as poly (femlene sulphide) can be obtained by applying solutions of the sulfur-containing polymer to the support material. The impregnations are made, for example, by impregnating an absorbent support material. Support materials that are used are generally inorganic substances such as glass, silica gel, alumina, sand, n &; ceramics, metals and organic substances such as plastics. For example, metals, in particular noble metals and transition metals or metal oxides such as transition metal oxides, can also be applied to the sulfur-containing polymers, for example by super-impregnation, these metals? Metal oxides are present, for example, in the form of small clusters. The process according to the invention can be carried out at any temperature which is below the softening point of the polymers used. The application temperature is generally on the scale from -30 to * -24Q ° C, preferably minus 25 to + 220 ° C. Nitrogen dioxide is generally eliminated in a quantitative way, the reaction times depend on the flow velocity, the surface of the purification material, '^ to the geometry of the absorber and the temperature. Generally, the contact time of the sulfur-containing polymer with the medium to be purified is in the range of 0.001 seconds to 10 minutes, preferably 0.01 seconds to 5 minutes. However, times may also be exceeded. In the elimination of N0a from gas containing N0? or liquid containing NO. ", no volatile polymer products are formed. The sulfur-containing polymer, for example poly (aplene thioether) may generally be used as unmixed Kvate. However, it is also possible to add commercial fillers such as clay, talc, clay, mica and / or fibrous reinforcements, such as glass fibers and / or carbon fibers, fine fibers and other conventional additives and processing aids, for example lubricants, release agents, an + antioxidants and UV stabilizers. The procedure according to this * nvenc? On can be used with gas and liquid streams containing NO ,. The process operates for example with gases having a NO content on the scale of 60% by volume to 1 ppb, preferably 50% by volume at 10 ppb and in particular 40% by volume at 50 ppb. The content of NO »that can be separated is on the scale of 50% by volume at lppb, preferably 20% by volume at 10 ppb and in particular % in volume at 10 ppb. The proportion in re the NO and the N0a in "*? S gases or liquids to be treated can in this case be of 1,000,000: 1 to 1: 1,000,000. preferably 10,000: 1 a 1: 10,000 and in particular form from 1000: 1 to 1: 1000. In the process according to the invention, the elimination of NOa can be carried out for example using one liter containing a sulfur-containing polymer. The removal of N02 from liquids or gases can also be effected, for example, by swirling a powder containing polymer with sulfur. This can be done by stirring a powder in a liquid. The procedure for removing N0a from liquids or * ses, can be carried out in an intermittent or column process, as is the case with other conventional adsorption processes for the purification of gases or liquids, or as is the case with the Separation procedures that are based on an adsorption process. The invention also relates to a filter for eliminating NOs from gases containing N0? or liquids containing N0 ?, said filter contains a polymer with sulfur. The specifications for the sulfur-containing polymer that are given in relation to the process according to the invention are applied correspondingly to the filter. The filter can also be operated in combination with other filter materials, for example dust filters. The filter containing a polymer with sulfur can contain the filter material for example in the form of a "* * - Packed powder, a nonwoven web, a nonwoven web / powder mix, a grid structure or a honeycomb structure. However, the powder can also be incorporated into non-woven webs of other materials. The process and the filter are particularly suitable for the production of NO test gases, in which case for example a crude NO gas is contaminated with N0H which contains a high concentration of NO, is passed through the filter and is purified in the course of this and then diluted to the desired concentration using an oxygen-free gas. The cases of dilution and filtration can also be carried out in parallel or in reverse order. The method and the filter according to the invention can also be used in medical technology. Thus, for example, in a treatment using uptake of NO through the lung, the gas containing NO and the added air can be combined in the initial part of, or in, the filter and in this way respiration of a mixture of free gas "You". The filter may comprise, for example, a breathing mask in the inlet stream from which the filter containing the polymer with sulfur is inserted. The filter according to the invention can be used to generate nitrogeno / nitrogen / air monoxide mixtures, free of N02 for the treatment of IRDS (IRDS = Infantile Respiratory Distress Syndrome), ARDS (= Acute Respiratory Upset Syndrome, also = Syndrome / "- Adult Respiratory Discomfort), pulmonary failure, migraine, persistent pulmonary hypertension based in left myocardial insufficiency or for improvement of lung function.

EXAMPLES 1). A so-called "NO" crude gas comprising approximately 20 vol.% NO in nitrogen, which was contaminated with 795 ppm NO-a due to its preparation, was passed through a filter cartridge packed with μl? femlene furo) (MW: 30,000, melting point TF: 288 ° C) in the form of granules (average particle diameter approximately 1 mm). The absorption section is characterized by the following parameters: Internal diameter 2.5 cm Bed height 32.5 cm Mass 100.5 g t '"Expense 100 1 / h At the exit of the absorbent bed, the gas is analyzed using an FTIR spectrophotometer (manufacturer: Perkin-Elmer, Uberlmgen, Federal Republic of Germany) and a N i / N0a luminescence measuring instrument (type CSI 1600, ColumbLa Scientific Instruments, Austm, Texas, USA) for NOs content. and not. Throughout the 4-hour period over which the measurements were taken, the concentration of N02 was below the detection limit of 100 ppb. 2) - A gas mixture of 158 ppm of NOs »in nitrogen was passed through through filter cartridge as in example 1. Immediately at the outlet of the filter, the NOs content of the gas mixture was determined by IR spectroscopy.The concentration of NOs was below the limit of detection. 3). ~ In a manner similar to that of Example 1, the capacity of the filter mentioned in Example 1 was determined using a gas J-start of 1% by volume of NO 2 and 99% by volume of nitrogen. The gas was passed through the filter until the NOa content of the gas in the final part of the filter increased above an NOa content of 1 ppm.The amount of gas flowing through the filter to reach the established limit of N02 content is defined as the absorption capacity of the filter. of 22 ° C, an absorption capacity resulted of approximately 2% by weight of the handle * "" 1 filter.

Claims

NOVELTY PE Lfl INVENTION CLAIMS

1. - A procedure for the preparation of gases or liquids containing NO that are free of NO, which comprises contacting a gas containing NO? or a liquid containing O with a material containing an "" olimero containing sulfur. 2.- A filter for the elimination of NOs »from gases containing NO or liquids containing NO, characterized in that it contains a polymer containing sulfur. 3. The process according to claim 1, or the filter according to claim 2, characterized in that the sulfur-containing polymer is a polythioether of aplene). 4. The process according to claim 1 or 3, or the filter according to claim 2 or 3, further characterized in that the sulfur-containing polymer is a poly (phenylene sulfide). 5. The method according to one or more of claims 1, 3 or 4, further characterized in that the NO-free gas is generated or the N02-free NO gas mixtures are generated. 6. The method according to one or more of claims 1, 3, 4 or 5 or the conformity filter c-r. any of claims 2 to 4, further characterized in that the sulfur-containing polymer is used as a powder, fiber, non-woven web, woven fabric, film, film portions, concreted material, molding, combination of two or more of the mentioned modalities , or as a coating or impregnation of support materials. 7. The method according to one or more of claims 1 and 3 to 6 or the filter in accordance with Either of claims 2 to 4 or 6, further characterized in that the sulfur-containing polymer has an average molecular weight in the range of 4000 to 200,000 units of atomic weight 8. The method according to one or more of the claims 1 and 3 to 7, also characterized in that the elimination of nitrogen dioxide is carried out at temperatures of minus 30 to + 240 ° C, preferably less than 25 to + 220 ° W. 9.- The use of a filter of confoimity with the claim 2 in a respirator 10. The use of a filter according to claim 2 for the generation of NO gas free of NO »or mixtures of NO gases free of NOs», in particular for gas generation NO-free test. "11. The use of a filter according to claim 2 for the generation of NOx, nitrogen monoxide / oxygen / air mixtures, for medical applications. P ~ 12.- The use of a filter according to claim 2 for the generation of NOx nitrogen / nitrogen / air mixtures, free of NOs », for the treatment of IRDS, ARDS, lung failure, migraines, asthma, Persistent pulmonary hypertension based on left myocardial insufficiency or for the improvement of lung function.