RU2229929C1 - Adsorbent for protection facilities - Google Patents

Abstract

FIELD: sorbents. SUBSTANCE: invention relates to production of carbon-based adsorbents, in particular those adsorbing organic vapors (benzene, toluene, cyclohexane, etc. ), inorganic gases and vapors (sulfur hydride, hydrogen cyanide, chlorine, etc.), acid gases and vapors (sulfur dioxide, hydrogen chloride, hydrogen fluoride, etc.), and ammonia in protection facilities. Adsorbent based on impregnated activated carbon is a mechanical mixture composed of two constituents, the first constituent (45-55 vol %) containing copper oxides 0.5-10.0% (calculated as copper) and sodium and/or potassium carbonate 3.0-17.0% and the second one (55-45 vol %) containing copper sulfate 12.0-15.0%. Carbon base utilized is activated carbon prepared from nut shell and/or fruit stone. EFFECT: prolonged protection time. 2 tbl

Description

The invention relates to the production of carbon-based adsorbents, in particular to the production of an adsorbent for the absorption of organic vapors (benzene, toluene, cyclohexane, etc.), inorganic gases and vapors (sulfur hydride, hydrogen cyanide, chlorine, etc.), acid gases and vapors (sulfur dioxide, hydrogen chloride, hydrogen fluoride, etc.) and ammonia in protective equipment.

It is known that active carbons intended for adsorption of organic vapors have a dynamic benzene activity of at least 75 min [AOOT EKhMZ, NPO Inorganika Active carbons. Elastic sorbents. Catalysts. Dehumidifiers. Chemical absorbers. / Catalog. - Cherkasy, 1996, p. 8-33].

Known absorber of ammonia and hydrogen sulfide [RU No. 2002104621, class. In 01 D 20/20, 02.20.2002], which is a carbon-mineral sorbent impregnated with copper sulfate in an amount of 12-15 wt.%. The known absorber provides a high degree of protection against ammonia, but does not protect against inorganic (except sulfur hydride) and acid gases and vapors, has a short protective time for organic vapors. The dynamic benzene activity of a known scavenger is 45-55 minutes.

Known acid gas absorber obtained by the method [RU No. 2138441, class. C 01 B 31/08, 31/16, B 01 J 20/20, 02.03.98], which is an active carbon impregnated with copper oxides in an amount of 5.0-9.5 wt.% In terms of copper and potassium carbonate in the amount of 5.9-9.4 wt.% in terms of potassium. The acid gas absorber is designed to absorb inorganic and acid gases and vapors.

The disadvantage of an acid gas absorber is the inability to absorb ammonia.

The closest in technical essence to the proposed adsorbent is a catalyst-absorber K-PA [TU 2165-044-05795731-00. Catalyst-absorber K-PA, Perm] based on activated carbon AG-5 [GOST 20777-75. Active carbon AG-5] containing copper compounds in terms of copper 4.5-7.5 wt.%, Chromium compounds in terms of chromium 1.2-2.2 wt.% And nickel chloride in an amount of 7-15 wt. .%. The K-PA absorbing catalyst is designed to absorb ammonia, inorganic and acid gases and vapors, toxic substances (chlorocyan, hydrogen cyan, phosgene, etc.).

The disadvantage of the K-PA absorbing catalyst is a short protective action for organic vapors and not high enough for inorganic and acid gases and vapors. The chromium compounds in the K-PA absorbing catalyst do not have a positive effect on its inorganic and acid gases and vapors absorption capacity, occupy a part of the sorption space, prevent the application of more other ingredients and the absorption of inorganic and acid gases and vapors using other ingredients. Nickel chloride in the K-PA absorbing catalyst blocks approaches for organic vapors to activated carbon micropores and is a corrosion-active component in relation to metal parts of gas filters.

The authors were faced with the task of developing a non-corrosive-active adsorbent based on activated carbon with a sufficiently high protective action time for organic vapors, inorganic and acid gases and vapors, and ammonia.

The result is achieved in that the adsorbent for protective equipment is a mechanical mixture of two component parts, while the first part in the amount of 45-55 vol.% Contains copper oxides as ingredients in terms of copper, 0.5-10.0 wt.% , sodium carbonate and / or potassium 3.0-17.0 wt.%, the second part in an amount of 55-45 vol.% contains 12.0-15.0 wt.% copper sulfate, and activated carbon is used as a carbon base from the shell of a nut and / or fruit kernel.

The difference of the proposed adsorbent is that:

- the adsorbent further comprises sodium carbonate and / or potassium;

- the adsorbent does not include compounds of chromium and nickel;

- a mechanical mixture of two components of the adsorbent is used: with copper oxides and sodium and / or potassium carbonate (45-55 vol.%) and with copper sulfate (55-45 vol.%);

- the first component of the adsorbent contains copper oxides in terms of copper in an amount of 0.5-10.0 wt.% and sodium and / or potassium carbonate in an amount of 3.0-17.0 wt.%;

- the second component of the adsorbent contains copper sulfate in an amount of 12.0-15.0 wt.%;

- the adsorbent for protective equipment contains ingredients on activated carbon from the shell of a nut and / or fruit kernel.

The first component of the proposed adsorbent provides the absorption of organic vapors, inorganic and acid gases and vapors.

The second component of the proposed adsorbent provides the absorption of organic vapors, sulfur hydride and ammonia.

The choice of a mechanical mixture of two constituent parts as the proposed adsorbent is caused by an increase in the length of the working layer of each of the constituent parts.

A narrow range of the ratio of the two constituent parts of the proposed adsorbent, 45-55 vol.% And 55-45 vol.%, Respectively, provides the necessary optimal mixing of the two constituent parts, especially for small adsorbent layers.

Activated carbon in the proposed adsorbent is necessary for the absorption of organic vapor.

The choice of walnut shell (walnut, coconut, etc.) and / or fruit kernel (peach, apricot, plum, etc.) as the base of activated carbon is due to the fact that the activated carbon obtained from it is characterized by high strength and developed porous a structure that allows both the introduction of the required amount of ingredients into coal and the sorption of organic vapors with high dynamic activity.

Copper oxides in the proposed adsorbent are necessary for the absorption of inorganic gases and vapors and, to a lesser extent, acid gases and vapors.

Sodium carbonate and / or potassium in the proposed adsorbent is necessary for the absorption of acid gases and vapors and some inorganic gases and vapors.

The copper sulfate in the proposed adsorbent is necessary for the absorption of sulfur hydride and ammonia.

The choice of copper sulfate as an ingredient to the proposed adsorbent is also due to the fact that the second component with copper sulfate, in contrast to other impregnated active carbons for the absorption of ammonia, for example active carbon with nickel chloride, has a color difference with the first component: grain the first part is black or dark gray in color, and the grains of the second part are gray or gray-blue. This property allows us to evaluate the uniformity of the adsorbent.

The proposed adsorbent is prepared as follows.

Activated carbon of one batch is supplied with one part for impregnation with solutions of carbonic ammonia of copper and sodium carbonate and / or potassium, with another part for impregnation with a solution of copper sulfate.

Prepare copper carbonate ammonia and sodium and / or potassium carbonate in one solution, or solutions of copper carbonate and sodium and / or potassium carbonate separately, or separately, and then mixed. Activated charcoal is impregnated either with a mixture of solutions, or sequentially at the beginning with one of the solutions, then with another with an intermediate heat treatment after aging. The ratio of activated carbon by weight in kg and impregnating solution by volume in dm ³ take 1: (0.4-0.8), respectively. After the end of the impregnation and aging, activated carbon is subjected to heat treatment at a temperature above 100 ° C to the desired moisture content.

Copper sulfate is applied to activated carbon in one or two stages by impregnating coal with a solution of copper sulfate, followed by heat treatment at temperatures above 100 ° C to the desired moisture content. The ratio of coal and impregnating solution is taken based on the total pore volume and the impregnation coefficient of 0.7-1.0.

The mixing of the two constituent parts of the adsorbent is carried out mechanically in a mixing device for bulk products.

The absorption capacity of the proposed adsorbent, as well as its prototype and analogues are given in table 1.

The data in table 1 show that the proposed adsorbent in comparison with the prototype has a higher dynamic activity for benzene and sulfur hydride, in comparison with the first analogue provides protection against sulfur dioxide and has a higher dynamic activity for benzene, and in comparison with the second analogue provides protection against ammonia and has a higher dynamic activity on benzene.

The decrease in the content in the first component of the copper adsorbent less than 0.5 wt.% And sodium carbonate and / or potassium less than 3.0 wt.% Leads to a decrease in the dynamic activity of sulfur hydride to the level of the prototype.

An increase in the content in the first component of the copper adsorbent above 10.0 wt.% Is technologically impossible because of the incomplete dissolution of the calculated amount of copper carbonate in the ammonia solution and the missing amount of copper falling into the pores of activated carbon, especially when forming a mixture of solutions of copper carbonic ammonia and sodium carbonate and / or potassium.

An increase in the content of sodium and / or potassium carbonate in the first component of the adsorbent above 17.0 wt.% Is impractical, since it does not lead to an increase in dynamic activity due to a decrease in the porosity of the coal base and blocking of the active centers of additives, clumping and sticking of adsorbent grains, salting out of additives adsorbent particles.

The choice of the ratio of the constituent parts of the proposed adsorbent is given in table.2.

The data in table 2 show that the optimal ratio of constituent parts in the proposed adsorbent 45-55 vol.% And 55-45 vol.%.

A decrease in any of the constituent parts of less than 45 vol.% Or an increase of more than 55 vol.% Leads to uneven distribution of parts in the layer and a significant decrease in the dynamic activity of one of the substances.

The proposed adsorbent has a sufficiently high protective time for organic vapors, inorganic and acid gases and vapors, and ammonia.

The proposed adsorbent does not have corrosive activity in relation to the metal parts of gas filters.

The proposed adsorbent was manufactured in pilot batches and tested in the laboratory. The test results confirmed the previously achieved test results of laboratory samples of the adsorbent.

Planned serial production of the proposed adsorbent for industrial protective equipment brand AVEK.

Claims (1)

The adsorbent for protective equipment based on impregnated activated carbon, characterized in that it is a mechanical mixture of two components, the first part in the amount of 45-55 vol.% Contains copper oxides as ingredients in terms of copper 0.5-10 , 0 wt.%, Sodium carbonate and / or potassium 3.0-17.0 wt.%, The second part in an amount of 55-45 vol.% Contains 12.0-15.0 wt.% Copper sulfate, and as coal base used activated carbon from the shell of a nut and / or fruit kernel.

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