RU1787492C - Method of producing adsorbing material - Google Patents

Abstract

The invention relates to a sorption technique, in particular to methods for producing absorbent materials, and can be used to obtain filters for absorbing organic solvent vapors from gaseous media. Absorbent material is obtained by introducing in 100 wt.h. acrylic emulsion 3-5 m.h. 25% solution of ammonium nitrate, 1-3 m.h., melamine-formaldehyde resin, 1-2 m.h. dioctyl phthalate and 8-9 m.h. water, mixing in an ultrasonic field with 36-63 m.y. silica gel with grafted groups —CH3, —OCaHs, —CeHg, —OsbHt3, applying the resulting mixture to 8-17 m.c. cotton base with a layer of 0.2-0.5 mm and subsequent heat treatment. 1 tab. (L C

Description

The invention relates to the field of sorption technology, in particular, to methods for producing absorbent materials and can be used to obtain filters for absorbing organic solvent vapors from gaseous media.

A known method for producing an absorbent material by applying a dispersion of binder and particles of hydrophobized silica gel 1 onto a nonwoven fibrous base is used. The material has a high sorption capacity for vapors of organic substances with a low sorption capacity for vapors of water, but contains a rigid polymer binder (polyacryamide, etc. d.), not providing high abrasion resistance of the material. Another disadvantage of the known technical solution is the necessity of introducing porophore, which complicates the synthesis technology.

The closest to the proposed invention in terms of technical essence and the achieved effect is a method for producing an absorbent material by applying an adhesive composition based on acrylic dispersion (possibly mixed with adsorbent powder) in the form of dots with a size of 0.2-2.0 mm, and then adsorbent particles. The resulting material has a reduced stiffness, high specific surface area (from 100-250 m2 / g to 1500 m / g). The disadvantages of the method are the high capacity for water vapor, as well as the low resistance of the binder to moisture, which leads to the possibility of dusting and shedding and limits the use of the material in wet conditions. In addition, since the adsorbent is applied to the surface of the adhesive VJ 00 XI

Yu Yu

layer, it is more susceptible to moisture. A negative feature of the known material is also a complex technology, including the following operations:

- preparation of an acrylic binder with a thickener; ammonium acrylate;

- applying in a discrete manner a binder to the substrate;

- Entering granules of adsorbent from a vibratory funnel;

- drying at a temperature of 120 ° C.

The aim of the invention is to increase the selectivity for organic vapors in the presence of water vapor, increase the strength and resistance in acidic and alkaline environments.

The invention is illustrated by the following examples:

Example 1

An adhesive composition is prepared containing May 100, h. acrylic emulsion TU 6-01-1259-81 AK-211-23, 3 parts by weight ammonium nitrate OST3760-64 (25% solution), 1 wt.h. metazin TU 6-14-700-82 (melamine-formaldehyde resin), 1 parts by weight, dioctyl phthalate, 8 parts by weight water, mixed in an ultrasonic field with 36 wt.h. silica gel KSK-1 with grafted -CH3 groups and applied using a squeegee with a layer of 0.5 mm to a surface of 17 parts by weight Cotton base and heat treat.

The table shows the compositions of the compositions obtained analogously to example 1.

As can be seen from the table, the materials obtained in accordance with the specified ranges of the compositions have a high selectivity coefficient for organic vapor (benzene) relative to water vapor (K 10-15). which practically does not decrease after exposure to acidic, (8) and alkaline (, 7) media.

The introduction of silica gel with a dispersion of less than 60 microns does not achieve the goal, since the sorption capacity of the resulting compositions is low (Ex. 6). The introduction of silica gel with a dispersion of more than 130 μm leads to a low strength of the sorbent layer and high heterogeneity (Ex. 7). The introduction of less than 36 parts by weight silica gel leads to a reduced capacity of the material (Ex. 8), and the introduction of more than 63 parts by weight silica gel (Ex. 9) - to increased stiffness of the material. The introduction of less than 113 parts by weight adhesive composition leads to reduced strength of the material, to low resistance to acids and alkaline (Ex. 10), and more than 119 parts by weight adhesive composition (Ex. 11)

- to low sorption capacity of the material.

Application to a cotton base with a content of less than 8 parts by weight in the material leads to low strength, dusting of the composition (Ex. 12), and more than 17 parts by weight. - to low sorption capacity of the material

(Ex 13). Application to the substrate with a layer of less than 0.2 mm leads to a low sorption capacity of the material (Ex. 14), a low selectivity, and applying to a layer with a thickness of more than 0.5 mm (Ex. 15) leads to

high rigidity of the material.

Mixing hydrophobic silica gel with an adhesive composition without exposure to ultrasound (Ex. 16) results in an uneven coating of low strength.

As can be seen from the above examples, the use of the invention allows to increase the coefficient of selectivity of the material for organic substances in relation to water 5-6 times (for

the proposed material K 10-15, for the material of the prototype, 1-2.5); to give resistance to the action of acids and alkalis (the proposed material retains the selectivity coefficient and strength, in the prototype material the selectivity coefficient decreases by 1.4-2.3 and the strength by 1.7-3.5 times).

Claims (1)

SUMMARY OF THE INVENTION A method for producing an adsorbent material, comprising preparing an acrylic binder, mixing it with 60- particles of adsorbent particles. 130 microns, applying the mixture to a cotton base and heat treatment, characterized in that, in order to increase the selectivity to organic vapor in the presence of water vapor, increase strength and chemical resistance, the preparation of the binder is carried out by introducing 100 parts by weight acrylic emulsion 3-5 wt.h., 25% aqueous solution of ammonium nitrate, 1-3 wt.h. melamine-formaldehyde resin, 1-2 parts by weight dioctyl phthalate and 8-9 parts by weight water, silica gel with the grafted groups —CH3, —OCaHs, -CeHs, -OSbNtz, mixing is carried out during sonication at the rate of 36-63 parts by weight silica gel per 100 parts by weight acrylic emulsion, the resulting mixture is applied to 8-17 parts by weight cotton base.