RU2399391C1 - Filter catalytic material - Google Patents

Abstract

FIELD: medicine, life saving equipment.

SUBSTANCE: invention can be used in individual respiratory protection - filter half-mask respirators and small-sized dynamic air cleaning systems. A filter catalytic compound material for air clearing from aerosols and carbon monoxide contains two layers of a fibrous filter medium and a layer of catalytic material. The layer of catalytic material is made of needled felt of surface density 220-250 g/m³, filled is a fine ground palladium-containing low-temperature carbon monoxide oxidation catalyst with particle size to 100 mc in the following ratio, wt %: catalyst - 15-50 %, fibrous filter medium - the rest, and is arranged between the layers of filtering medium made of electrostatic fine-filamented polymer fibres.

EFFECT: enabled humidity operation, reliable catalyst fixation in a layer and carbon monoxide and aerosol protection.

5 cl, 1 tbl

Description

The invention relates to the field of air purification from aerosols and carbon monoxide at concentrations up to 5-10 norms of maximum permissible concentration and can be used in personal respiratory protective equipment (RPE) - respirators in the form of a filtering half mask of fibrous materials and small-sized dynamic air purification systems.

The widespread use in respiratory protection is filter materials Petryanova (FP) (I.V. Petryanov, V.I. Kozlov and others. "Fibrous filtering materials." M .: Knowledge, 1968). The materials are uniform layers of ultrathin polymer fibers deposited during fabrication on a fabric substrate (gauze, calico) or on a base of thick polymer fibers bonded together (non-woven fabric). These materials are widely used in personal protective equipment to protect respiratory organs from aerosols (I.V. Petryanov et al. “Petal” (Light respirators). - M .: Nauka, 1984). With low aerodynamic drag, these materials have high aerosol protection, which, depending on the brand, is 95–99.9%, but these materials do not allow air purification from harmful gases and vapors.

For comprehensive protection against aerosols and gases, sorption-filtering (filter-sorbing) or filter-catalytic materials (FCM) are used.

The biggest problem in this case is the provision of the necessary protective properties of fibrous materials with acceptable resistance to air flow in a thin (3 - not more than 5 mm thick) layer. In this case, only highly active adsorbents and chemisorbents are used.

These requirements are due to the physiological capabilities of the person and are accordingly regulated by the standards for filtering RPDs. So, for example, the resistance of a filtering half mask of class FFP2 and FFP3 at a volumetric constant flow rate of 30 l / min (GOST R 12.4.191-99) should not exceed 70 and 100 Pa, respectively.

Known from RF patents RU No. 2068282, A62B 7/10, 1996, RU 2161338, G21F 9/02, 2000, RU 2185877, B01D 32/02, 2002, RU 2230610, B01J 20/20, 2004, RU 2281798, A62B 23 / 02, 2006 sorbent fibrous materials used for air purification at concentrations up to 5 norms of the maximum permissible concentration of the working area (MPC), inside which a powdery sorbent is placed: either activated carbon - for the absorption of organic substances, or soda - for absorption acid gases, or coal impregnated with potassium iodide - to absorb radioactive iodine. A disadvantage of the known materials is that they do not clean the air of carbon monoxide.

Known by US Pat. RU 2153386, B01D 39/00, 2000, a seven-layer fibrous sorption-filtering protective material containing an aerosol sorbing layer of perchlorovinyl fibers and several gas-filtering layers of polymer and / or carbon fiber materials. This material does not protect against CO, having a high resistance, cannot be used in lightweight RPPS.

Known filtering element for air purifiers harmful industries (US Pat. RU 2195993, B01D 39/14, 2003), with the ability to protect against CO at a concentration of 0.1 mg / L. The element is made of a thermoplastic polymer in which catalyst particles are distributed, bonded together by particles of a thermoplastic polymer uniformly distributed between them. The disadvantage of this material is that it is made in the form of tablets or hollow cylinders and cannot be used in systems of complex configuration, for example, in filtering respirators having a cup shape.

The closest technical solution to the proposed material is the sorbent filter material according to patent RU No. 36238, A62B 23 / 02,2004, containing a layer of ion-exchange fibrous filter material with air permeability of 220-390 dm ³ / (m ² s) and a finely ground oxidation catalyst filling it CO - hopcalite with a particle size of 20-40 microns.

The disadvantage of this filter is that this sorbent filter material with a hopcalite catalyst:

a) it is ineffective when used in a humid atmosphere without an additional desiccant layer, which leads to a limitation of its use in objects having a small thickness and limited resistance in dynamic conditions, for example, in filter masks weighing up to 50 g and a thickness of not more than 5 mm;

b) it is not able to firmly hold catalyst particles with a size of 20-40 microns in a layer of material in dynamic flows, which leads to their blowing during use, the redistribution of particles in the layer during transportation and storage, and this, in turn, will lead to loss of catalyst and the impossibility of ensuring high quality cleaning and, as a consequence, the impossibility of its use, for example, in respirators.

The technical problem to be solved and the technical result achieved is the creation of a filter-catalytic material that simultaneously possesses a set of the following useful properties:

- protection against carbon monoxide at a concentration of 5-10 MAC p.z. and aerosols

- low aerodynamic drag, which allows it to be used, in particular, in respirators in the form of a filtering half mask with an air flow resistance of not more than 100 Pa at a space velocity of 30 l / min (GOST R 12.4.191-99),

- the ability to retain catalyst particles in a layer of filter-catalytic material.

The technical result is achieved by the fact that the filter material contains a fibrous catalytic layer (layer 1), consisting of needle-punched filter material (IM) with a surface density of not more than 220-250 g / m ³ with powder particles (finely divided) uniformly distributed in its volume up to 100 microns of a palladium-containing catalyst for low-temperature oxidation of carbon monoxide at high humidity with a ratio of components, wt.%:

catalyst -15-50,

IM - the rest,

which is located between the layers of filter material made of electrostatically charged fine fiber polymer fibers (layers 2, 3).

The layers of fine-fiber filtering material from electrostatically charged polymer fibers have the same resistance or one layer has a resistance of 13-19 Pa (layer 2), the other layer is 6-10 Pa (layer 3) with a linear air flow rate of 1 cm / s. A layer of filtering material from electrostatically charged fine-fiber polymer fibers with a resistance of 6-10 Pa can serve as a substrate for the catalytic layer.

When the catalyst concentration in the catalytic layer is lower than 15%, carbon monoxide breakthrough occurs, with an increase in concentration above 50%, the filter layers should have a minimum resistance, which leads to an increase in the aerosol penetration coefficient.

The difference and advantage of the proposed filter-catalytic material (FCM) in comparison with the known one is that the used palladium-containing catalyst for low-temperature oxidation of carbon monoxide showed sufficient activity at high air humidity, which allows the use of a catalyst with particles of a larger fraction (up to 100 μm, in the prototype 40 -60 μm), the catalytic layer is located between the layers of fine fiber filter material, additionally holding the catalyst particles during use lzovanii material in a dynamic air stream. The layers of fine fiber filter material also provide air purification from aerosols of any degree of dispersion.

The use of these features in the proposed material allows to achieve high quality air purification from carbon monoxide and aerosols when using this material for air purification in household air purifiers and in lightweight respirators by completely eliminating aerosol leakage and reducing the concentration of carbon monoxide to acceptable standards and thereby increase reliability protection.

The invention is confirmed by examples 1-7 presented in the following table.

For testing, we took the catalyst according to TU 2178-046-05784466-2007 (manufactured according to patent RU 2267354, B01J 23/89, 2006), fibrous materials: for the catalytic layer - needle-punched filter material (for example, material made of 100% polyester fiber or fibrous material Geokom D-160, material art. 073 (200) -FA-2,073 (250), FA-3) with a surface density of 220-250 g / m ² , for filter layers - material from electrostatically charged fine-fiber polymer fibers with different air flow resistance (see table, examples 1-7).

The penetration coefficient (KPR) by oil mist (MT) aerosol with a particle diameter of 0.29-0.34 μm and the material resistance were determined according to GOST 12.4.028-76.

The protective efficacy of CO under dynamic conditions was evaluated by the time of a 50% decrease in CO concentration at a flow humidity of 70%, a temperature of 21 +/- 2 ° C, and a CO concentration of 200 mg / m ³ . The tests were carried out on the installation of the dynamic type "Dynamics-4" at a linear flow rate of 2 cm / s. The initial and output, in mg / m ³ , concentration of carbon monoxide was determined by a Magnistor gas analyzer (developed and manufactured by Monitoring LLC). Permissible basic error is ± 20% with a measurement range of 0-50 PPM.

Table Example No. The ratio of components in layer 1, mass,% FKM layers Resistance at a flow rate, Pa KPR MT,%, no more Protective effectiveness, min 1 cm / s 30 l / min one catalyst - 15.4%, Layer 1 - Layer 2 fifteen VM - the rest Layer 3 6 FCM - 48 +/- 5 0.8 22 +/- 5 2 catalyst - 15.4%, Layer 1 - Layer 2 6 VM - the rest Layer 3 6 FCM - 38 +/- 5 1.0 20 +/- 5 3 catalyst - 27%, Layer 1 - Layer 2 fifteen VM - the rest Layer 3 6 FCM - 60 +/- 9 0.8 56 +/- 10 four the catalyst is 35%, Layer 1 - Layer 2 fifteen VM - the rest Layer 3 6 FCM - 71 +/- 5 0.8 83 +/- 10 four catalyst - 42%, Layer 1 - Layer 2 fifteen VM - the rest Layer 3 6 FCM - 79 +/- 5 0.8 112 +/- 15 5 catalyst - 46.6%, Layer 1 - - Layer 2 fifteen - VM - the rest Layer 3 6 - FCM - 80 +/- 7 0.9 135 +/- 15 6 catalyst - 46.6%, Layer 1 - - Layer 2 fifteen - VM - the rest Layer 3 fifteen - FCM - 99 +/- 5 0.8 133 +/- 15 7 catalyst - 52% Layer 1 - - Layer 2 6 - VM - the rest Layer 3 6 - FCM - 89 +/- 5 2.8 139 +/- 15

The table shows that an increase in the time of the protective effect due to the introduction of a larger amount of catalyst increases the resistance, which reaches a limit value when the catalyst content is above 50% (example 7), a decrease in the resistance of the layers of filtering materials to 6 Pa (example 7) leads to an increase in the coefficient penetration of a test aerosol.

Thus, a filter-catalytic material is proposed that provides protection both from carbon monoxide and from aerosols, capable of working at high air humidity and ensuring satisfactory retention of the catalyst in the layer.

Based on the proposed filter-catalytic material, respirators are manufactured. Laboratory and operational tests were carried out in and at the workplace of traffic police officers. Respirators received a positive assessment with their experienced wear.

Further production of the material and its use are planned.

Claims (5)

1. Filter-catalytic material for cleaning air from aerosols and carbon monoxide, including a catalytic fiber layer, which is a filter fiber material filled with a finely divided catalyst, characterized in that the catalytic fiber layer is made of needle-punched fiber material with a surface density of 220-250 g / m ³ filled with a palladium-containing catalyst for low temperature oxidation of carbon monoxide with a particle size of up to 100 microns; the content of the catalyst in the layer is 15-50%, and this layer is located between the layers of filter material made of fine-fiber electrostatically charged polymer fibers. 2. The filter-catalytic material according to claim 1, characterized in that the layers of the filter material have the same resistance to constant air flow in dynamic conditions. 3. The filter-catalytic material according to claim 1, characterized in that the layers of the filter material have different resistance to constant air flow in dynamic conditions. 4. The filter material according to claim 3, characterized in that one layer of filter material has a resistance of 13-19 Pa, and the other 6-10 Pa at a linear air flow rate of 1 cm / s. 5. The filter material according to claim 4, characterized in that the layer of filter material with a resistance of 6-10 Pa is a substrate for the catalytic layer.