RU2336945C1 - Sorbent "с-кп" for atmospheric air purification - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: sorbent is obtained by feathering of silted, granulated and dried clay with pyrolusite with further burning. Sorbent is active with respect to oxides of nitrogen, carbon and sulfur, as well as formaldehyde and butylmercaptane.

EFFECT: higher sorbent activity.

2 cl, 3 tbl

Description

The invention relates to a technology for purification of atmospheric air by a sorbent from organic and inorganic industrial toxicants, as well as the destruction of pathogenic bacteria, and can be used in the chemical, petrochemical and gas industries, chemical and bacteriological laboratories, hospitals, pharmacies, shops, including special-purpose enterprises (air defense services, command posts, control systems for various services).

A known method of purification of atmospheric air from hydrogen sulfide (RU 2254916, 06.27.2005). The invention relates to methods for preparing a sorbent for cleaning gases from hydrogen sulfide and may find application in the purification of atmospheric air from hydrogen sulfide. This is achieved by the fact that in the method of preparing the sorbent for cleaning gases from hydrogen sulfide based on activated carbon, the moisture content of the initial active carbon and its moisture capacity are preliminarily determined. Then, for applying promoters to the source of activated carbon, an impregnating aqueous solution is prepared with a content of 0.5-3.5 wt.% Potassium iodide based on the weight of the source of active carbon, to which 0.035-0.075 wt.% Of monoethanolamine based on the weight of the source of active carbon is additionally added. The amount of water for the preparation of the impregnating solution is taken based on the mass of activated carbon. Sorbent provides high performance air purification process and avoids frequent replacement of the catalyst.

However, the main disadvantage of this method is the inability to purify other acid gases and vapors of organic substances (formaldehyde and butyl mercaptan) in the complex, as well as to destroy pathogens.

Known is a comprehensive method for cleaning air from dust and toxic substances (RU 2163834, 03/10/2001). The invention can be used for wet cleaning of gases by interacting with a countercurrent liquid of a contaminated gas stream and emulsification. To do this, a stream of contaminated gas swirled by a tangential inlet is fed into an annular gap in which the gas is swirled in the opposite direction with a blade swirl and the gas-liquid mixture is emulsified over a wide range of speeds. The method is implemented in a device for wet cleaning of gases, comprising a cylindrical body, a tangential gas supply pipe, a disk-shaped liquid dispenser, a blade swirler placed in an annular slot with a swirl opposite the inlet pipe. The outer ends of the outlet edges of the swirlers are raised above the inner adjacent to the fluid dispenser. The inlet pipe of the scrubber is equipped with nozzles for washing off dust deposits and a system of automatic periodic supply of flushing water, triggered by rarefaction in the duct and allowing the nozzles to be purged with atmospheric air. The scrubber body is made in the form of a regular prism, and the liquid dispenser is a polygon similar to the base of the prism.

A method for purifying air from harmful impurities and a device for its implementation (RU 2161567, 2001.01.10) are proposed. The invention relates to methods for cleaning and conditioning air from impurities in relatively tight rooms, mainly in vehicle interiors, but it can also be used in other relatively tight rooms. A method of purifying air from harmful impurities in relatively tight rooms is that the cleaning is carried out alternately by two flows supplied by the fans from a relatively tight room of air from moisture and organically harmful impurities by means of adsorption filters, from chemisorbed compounds and catalytic poisons, by means of a low-temperature catalytic filter. Alternately in one of the streams, the adsorption filter that is currently idle is regenerated, each of which includes a double layer of silica gel and activated carbon due to moisture adsorbed on silica gel by heating this adsorption filter to 160 ° C. Then it is cooled with a fan, while maintaining a balance of the volumes of air coming from the atmosphere into a relatively tight room, and the discharge of this air into the atmosphere during the regeneration process.

A known method of purifying air from toxic substances (RU 2202402, 04/20/2003). The method relates to sorption-catalytic purification of air from pollutants and can be used for cleaning systems from toxic components of exhaust gases and exhaust industrial ventilation emissions. The method of purifying air from toxic components of exhaust and exhaust gases includes passing the air flow sequentially through a mechanical filter to remove particulate matter and aerosols, a device for heating air to a temperature above ambient temperature by 5-30 ° C, a layer of sorbent that absorbs hydrocarbons and others organic compounds, a layer of a porous polymer sorbent containing polyether in the pores for adsorption of metals, and a layer of a redox catalyst based on ve manganese oxides and copper for cleaning air of toxic exhaust components. The proposed method allows to achieve a tenfold decrease in the concentration of harmful components of exhaust gases (CO, nitrogen oxides, etc.) and reduce the concentration of heavy metals in ventilation industrial emissions to MPC values and below.

This method provides high performance in the process of purifying air from toxic components of exhaust gases with its high efficiency and avoids frequent replacement of the catalyst.

However, the main disadvantage of this method, taken by us as a prototype, is its inability to clean a number of organic compounds and metals from air ventilation flows.

The task of the invention is the creation of a multi-use sorbent with universality of action, as well as the necessary sorption and technological characteristics.

The problem is solved by the fact that a new sorbent C-KP is proposed, which is expanded clay granules coated with a thin layer of pyrolusite. Sorbent C-KP is intended for purification of atmospheric air from oxides of nitrogen, carbon, sulfur, formaldehyde and butyl mercaptan, obtained by drying silted, granular and dried clay with pyrolusite, followed by calcination at 1150-1200 ° С.

The resulting sorbent corresponds to the following chemical composition (wt.%):

aluminium oxide 66.8-69.6 silica 27.0-28.05 iron oxide 1.4-1.6 sodium chloride 0.3-0.5 calcium carbonate 0.7-0.77 pyrolusitis 0.83-1.0

Experiments were conducted on the purification of atmospheric air from various toxicants on the sorbent C-KP.

In order to study air purification in bottles with a capacity of 5 dm ³ , a small vacuum was created using a vacuum pump (residual pressure ~ 0.6–10 ⁵ n / m ² ) and gases or vapors of the test substance were passed through a special pipe. Vapors were generated by heating a sample of a substance (acetone, formaldehyde, etc.) in a test tube with a gas outlet tube or as a result of a chemical reaction of copper with sulfuric or nitric acids (respectively, SO ₂ or NO ₂ gases were obtained). Then air was let into the bottle to bring the total pressure to 1.02-10 ⁵ n / m ² and a mixture of air and test gas from the bottle was passed through sorbent granules with a diameter of 20 mm, creating a vacuum at the outlet of this tube.

где m_исх - содержание сорбата в воздухе до очистки, мг/м³, m_кон - содержание сорбата в воздухе после очистки, мг/м³.Table 1 shows the results of experiments on the purification of atmospheric air into which certain toxicants were introduced. The degree of purification S was calculated by the formula

where m _ref is the content of sorbate in the air before purification, mg / m ³ , m _con is the content of sorbate in the air after purification, mg / m ³ .

Table 1 The results of air purification from various toxicants.
Nitric oxide (NO). MPC _CC - 0.06 mg / m ³ , MPC _m.r. - 0.4 mg / m ³ Contact time, s The initial concentration of m _ref , mg / m ³ Cleaning results Found, m _con S,% 0 5,0 5.0 ± 0.5 0,0 1,0 5,0 4.00 ± 0.05 20,0 2.0 5,0 2.0 ± 0.05 60.0 5,0 5,0 1.5 ± 0.05 70.0 0 10.0 10.0 ± 0.10 0,0 1,0 10.0 5.0 ± 0.5 50,0 2.0 10.0 4.0 ± 0.4 60.5 5,0 10.0 3.0 ± 0.25 70.0 0 50,0 50 ± 5.0 0,0 1,0 50,0 20.0 ± 2.0 60 2.0 50,0 15.0 ± 0.10 70 5,0 50,0 5.0 ± 0.5 90 0 100.0 100.0 ± 2.5 - 1,0 100.0 20 ± 2.0 75.0 2.0 100.0 20.0 ± 2.0 80.0 5,0 100.0 5.0 ± 0.5 95.0 Sulfur dioxide (SO ₂ ). MPC _m. - 0.1 mg / m ³ Contact time, s The initial concentration of m _ref , mg / m ³ Cleaning results Found, m _con mg / m ³ 0 5,0 5.0 ± 0.5 S,% 1,0 5,0 0.005 ± 0.001 99.90 2.0 5,0 0.005 ± 0.001 99.90 5,0 5,0 0.005 ± 0.001 99.90 0 50,0 50.0 ± 0.50 - 1,0 50,0 0.01 ± 0.002 99.98 2.0 50,0 0.01 ± 0.002 99.98 5,0 50,0 0.01 ± 0.002 99.98 0 200,0 200 ± 10.0 99.5 1,0 200,0 1.0 ± 0.25 99.5 2.0 200,0 1.0 ± 0.05 99.5 5,0 200,0 1.0 ± 0.05 - 0 1000 1000 ± 50 99.50 1,0 1000 4.0 ± 0.50 99.60 2.0 1000 1.0 ± 0.15 99,910 5,0 1000 1.0 ± 0.15 99.90 Hydrogen sulfide (H ₂ S). MPC _m. - 0.008 mg / m ³ Contact time, s The initial concentration of m _ref , mg / m ³ Cleaning results Found, m _con mg / m ³ S,% 0 0.05 0.05 - 1,0 0.05 0.001 98.0 2.0 0.05 0,0005 99.0 5,0 0.05 0,0003 99,4 0 0.5 0.001 99.80 1,0 0.5 0.001 99.80 2.0 0.5 0,0005 99.80 5,0 0.5 0,0003 99.94 0 1.00 0.001 99.90 1,0 1.00 0.001 99.90 2.0 1.00 0,0005 99.95 5,0 1.00 0,0003 99.97 0 10.0 0.002 99.98 1,0 10.0 0.002 99.98 2.0 10.0 0.001 99,99 5,0 10.0 0.001 99,99 Nitrogen dioxide (NO ₂ ). PDK _S.S. - 0.04 mg / m ³ , MPC _m.r. - 0.08 mg / m ³ Contact time, s The initial concentration of m _ref , mg / m ³ Cleaning results Found, m _con mg / m ³ S,% 0 200,0 200 ± 10.0 0 1,0 200,0 20.0 ± 1.5 90.0 2.0 200,0 10.0 ± 1.0 95.0 5,0 200,0 0.50 ± 0.5 97.5 0 50,0 50.0 ± 2.5 - 1,0 50,0 5.0 ± 0.30 90 2.0 50,0 3.0 ± 0.30 94 5,0 50,0 1.0 ± 0.10 98.0 0 10.0 10.0 ± 1.0 - 1,0 10.0 1.0 ± 0.05 90.0 2.0 10.0 0.50 ± 0.10 95.0 5,0 10.0 0.03 ± 0.005 98.0 0 5,0 5.0 ± 0.25 - 1,0 5,0 1.0 ± 0.15 80.0 2.0 5,0 0.5 ± 0.03 90.0 5,0 5,0 0.2 ± 0.005 96.0 Carbon monoxide (CO). PDK _S.S. - 3.0 mg / m ³ , MPC _m.r. - 5.0 mg / m ³ Contact time, s The initial concentration of m _ref , mg / m ³ Cleaning results Found, m _con mg / m ³ S,% 0 1.00 1.0 ± 0.08 - 1,0 1.00 0.40 ± 0.03 99.90 2.0 1.00 0.01 ± 0.01 99.90 5,0 1.00 0.05 ± 0.0005 99.90 0 10.0 10.0 ± 1.0 - 1,0 10.0 5.8 ± 0.35 42.0 2.0 10.0 1.60 ± 0.10 84.0 5,0 10.0 0.05 ± 0.05 95.0 0 100.0 100.0 ± 2.5 - 1,0 100.0 20 ± 2.0 75.0 2.0 100.0 20.0 ± 2.0 80.0 5,0 100.0 5.0 ± 0.5 95.0 0 500,0 500 ± 20.0 - 1,0 500,0 100.0 ± 5.0 80.0 2.0 500,0 50.0 ± 3.5 90.0 5,0 500,0 10 ± 1,0 98.0 Butyl mercaptan Contact time, s The initial concentration of m _ref , mg / m ³ Cleaning results Found, m _con mg / m ³ S,% 0 0.05 0.05 ± 0.005 - 1,0 0.05 0.02 ± 0.003 60 2.0 0.05 0.01 ± 0.002 80 5,0 0.05 0.01 ± 0.002 80 0 1.00 1.0 ± 0.08 - 1,0 1.00 0.10 ± 0.003 90 2.0 1.00 0.05 ± 0.006 95 5,0 1.00 0.02 ± 0.005 98.0 0 10.0 10.0 ± 0.95 - 1,0 10.0 1.0 ± 0.09 90.0 2.0 10.0 0.50 ± 0.03 95.0 5,0 10.0 0.10 ± 0.002 99.0 0 50,0 50.0 ± 3.5 - 1,0 50,0 25.0 ± 1.5 fifty 2.0 50,0 10.0 ± 0.95 80 5,0 50,0 5.0 ± 0.3 90.0 Formaldehyde. PDK _S.S. - 0.003 mg / m ³ , MPC _m.r. - 0,035 mg / m ³ Contact time, s The initial concentration of m _ref , mg / m ³ Cleaning results Found, m _con mg / m ³ S,% 0 0.001 0.001 ± 0.0001 - 1,0 0.001 0,0005 fifty 2.0 0.001 0,0005 fifty 5,0 0.001 0,0005 fifty 0 0.10 0.10 ± 0.01 - 1,0 0.10 0.05 ± 0.005 fifty 2.0 0.10 0.05 ± 0.005 fifty 5,0 0.10 0.02 ± 0.005 fifty 0 1.00 1.0 ± 0.05 - 1,0 1.00 0.10 ± 0.01 90 2.0 1.00 0.05 ± 0.005 95 5,0 1.00 0.01 ± 0.001 99.0 0 10.0 10.0 ± 0.50 - 1,0 10.0 0.10 ± 0.01 99.0 2.0 10.0 0.05 ± 0.0053 99.50 5,0 10.0 0.01 ± 0.0003 99.90

From the results given in table 1, it can be seen that the sorbent C-KP can be used to clean the air of residential premises and working areas of industrial enterprises. The possibility of purifying atmospheric air from groups of toxicants has been studied. For this, the simultaneous generation of several toxicants was used. The results of air purification from a mixture of various toxicants are given in table 2.

table 2 The results of the sorption purification of atmospheric air from a number of toxicants present together. Contact time, s The concentration of the substance before purification, mg / m ³ , the air contains a mixture of substances, the concentration of each of which is indicated by numbers Cleaning results Found, m _con mg / m S,% 5,0 SO ₂ - 20.0 2.0 ± 0.10 90. NO ₂ - 20.0 2.0 ± 0.10 90.0 СО - 20.0 10 ± 0.95 50,0 H ₂ S - 10.0 0.01 ± 0.001 99,99 NO - 20.0 0.1 ± 0.001 99.5 NSON-20.0 2.0 ± 0.10 90.0 Average 86.57 5,0 SO ₂ - 100.0 4.0 ± 0.20 96.0 NO ₂ - 100.0 4.0 ± 0.020 96.0 CO - 100.0 25 ± 1,50 75.0 H ₂ S - 50.0 0.5 ± 0.05 99.5 NO - 100.0 0.01 ± 0.001 99.98 NSON-100.0 0.01 ± 0.001 99.98 Average 94.41

As can be seen from table 2, the sorption purification of atmospheric air using the sorbent C-KP is highly effective and can be recommended everywhere in cases where only chemisorption purification has a noticeable effect.

Experiments show that not only CO, CO ₂ , H ₂ S, NO, NO ₂ , phenol and formaldehyde are deactivated, but also all pathogens are destroyed. Table 3 shows the results of air purification from microorganisms. The indoor air was cooled by VK - 2500 air conditioners, but in one case the air was cleaned with an S-KP sorbent located in a canister and located along the flow of exhaust air. Six people worked in each of the premises (each shift worked for 4 hours, the work schedule was round-the-clock).

Table 3 Comparative characteristics of atmospheric air dissemination by natural microflora without use (control) and with the use of S-KP sorbent. The number of experiments is 6. Object of study - air Temperature ° C Relative humidity% The number of colonies of natural microflora in the Petri dish. Room 1 (control) 25 ± 2 80.0 ± 2.0 56.0 ± 5.0 Room 2 (using sorbent) 25 ± 2 80.0 ± 2.0 7.0 ± 1.0

As can be seen from table 3, the airborne contamination as a result of the use of the sorbent C-KP decreased approximately eight times in comparison with the control.

Thus, the sorption purification of atmospheric air from oxides of nitrogen, carbon and sulfur, hydrogen sulfide, formaldehyde and butyl mercaptan using the sorbent C-KP is highly effective.

Claims (2)

1. Sorbent C-KP for the purification of atmospheric air from oxides of nitrogen, carbon, sulfur, formaldehyde and butyl mercaptan obtained by drying silted, granular and dried clay with pyrolusite, followed by calcination at 1150-1200 ° C. 2. The sorbent according to claim 1, characterized in that it corresponds to the following chemical composition, wt.%: aluminium oxide 66.8-69.6 silica 27.0-28.05 iron oxide 1.4-1.6 sodium chloride 0.3-0.5 calcium carbonate 0.7-0.77 pyrolusitis 0.83-1.0