A method of producing a catalyst for purification of gases from nitrogen oxides

 

(57) Abstract:

The invention relates to the production of sorbents and catalysts used in individual and collective means of protection for air purification from nitrogen oxides, and can be used in the industrial production of catalysts. Describes a method of producing a catalyst for purification of gases from nitrogen oxides, comprising a mixture of manganese dioxide with a binder is bentonite clay, molding granules, drying, grinding and heat treatment, and the suspension containing manganese dioxide, enter the hydroxide of barium, which is made simultaneously with alkaline treatment of a mixture of manganese dioxide with a water-soluble salt of barium within 1 to 4 hours, and then spend a mixture of manganese dioxide and barium hydroxide with bentonite clay in the following ingredients, wt.%: manganese dioxide 40 - 60; barium hydroxide 30 - 50; bentonite clay 5 - 15. The technical result - the increase of catalytic activity of the catalyst. table 1.

The invention relates to the production of sorbents and catalysts used in individual and collective means of protection for air purification from nitrogen oxides, and can be used for the cleaning of gases from toxic impurities, in particular, oxides of nitrogen, comprising adding to the crushed powder of the active alumina solution of nitrate of copper, a small amount of water to make the mass of plasticity, forming and heat treatment of the granules at 280-300oC followed by impregnation with a solution of manganese nitrate and re-heat treatment (USSR and. C. N 986482 from 31.03.80, class B 01 J 23/84; B 01 D 53/86).

The disadvantage of this method is the difficulty of carrying out the process, due to the need for impregnation of heat-treated granules of the catalyst with a solution of manganese nitrate and subsequent heat treatment.

A known method of producing a catalyst for purification of exhaust gases from harmful impurities, including nitrogen oxides, comprising a mixture of components containing compounds of copper, barium, aluminum oxide, with iron oxide and hydroxochloride ruthenium, bringing the mixture to a plastic mass, molding, drying and heat treatment at the contents of the ingredients in the final product weight. %: barium oxide of 6.2-7.0 and aluminum oxide 61,4945-76,195; iron oxide 7,7-21,1; oxide of ruthenium 0,005-0,006; copper oxide - rest (USSR and. C. N 954098, publ. 30.08.82, class B 01 J 23/2; B 01 J 23/78; B 01 J 37/04).

The disadvantages of SPONTA due to the uneven distribution of promoting additives hydroxochloride ruthenium in the molding mass and low catalytic activity of the catalyst for purification of gases from nitrogen oxides.

There is also known a method of obtaining a oxidation catalyst exhaust or flue gases, comprising the mixing of oxides of manganese, copper and aluminum at a ratio of 7: 3: 10 dry, then add water for the formation of a pasty mass, the subsidence of the last dry, molding, drying the obtained pellets and pyrolysis at a temperature of 500-600oC for 1-2 h with complete removal of water (U.S. Pat. Japan N 51-48155 from 09.03.72, class B 01 J 23/84).

The disadvantages of this method are uneven mixing of ingredients in dry form because of the strong differences in the density of each component, as a consequence, the instability of the protective properties and not enough high catalytic activity of the obtained catalyst.

Closest to the proposed to the technical essence is a method of manufacturing a catalyst comprising a mixture of manganese dioxide and copper oxide with a binder is bentonite clay, molding granules, drying, grinding and heat treatment, the mixture of manganese dioxide and copper oxide is conducted simultaneously with the preparation of copper oxide at a temperature of 50-95oC for 0.5-3 h, and then spend a mixture of manganese dioxide and copper oxide with a binder. The catalyst of posed copper - 10-30, the binder is bentonite clay - 5-15 (see U.S. Pat. Russia N 2083279, publ. 31.10.95, class B 01 J 23/84; B 01 J 37/04).

The disadvantage of this method is the low catalytic activity of the resulting catalyst for purification of gases from nitrogen oxides despite the possibility of its use for these purposes (see and.with. The USSR SU 1641404 A, class B 01 D 53/36, publ. 15.04.91).

The aim of the invention is to increase the catalytic activity of the catalyst in the reduction of nitrogen oxides.

This objective is achieved in that a method of producing a catalyst for purification of gases from nitrogen oxides, comprising a mixture of manganese dioxide with a binder is bentonite clay - molding granules, drying, crushing, heat treatment is performed so that the first aqueous suspension of manganese dioxide is subjected to alkaline treatment simultaneously with the water-soluble salt of barium within 1-4 h, then the resulting paste containing manganese dioxide and barium hydroxide, is mixed with bentonite clay in the following ingredients, wt.%:

manganese dioxide - 40-60

the barium hydroxide - 30-50

bentonite clay - 5-15

The difference of the proposed method against known is that at the beginning of WWII for 1-4 h, then, the resulting paste containing manganese dioxide and barium hydroxide, is mixed with bentonite clay in the following ingredients, wt.%:

manganese dioxide - 40-60

the barium hydroxide - 30-50

bentonite clay - 5-15

The use of such techniques at the specified contents of the ingredients to obtain a catalyst of the scientific and technical literature authors unknown.

The use of these features in the proposed method of preparation of the catalyst allows to achieve high quality catalysts, which becomes possible due to the fact that the first aqueous suspension of manganese dioxide is subjected to alkaline treatment simultaneously with the water-soluble salt of barium within 1-4 h, then the resulting paste containing manganese dioxide and barium hydroxide, is mixed with bentonite clay at the specified contents of the ingredients to obtain a catalyst.

The method is as follows.

Prepare aqueous suspension of manganese dioxide and add caustic sodium. After dissolution of the latter in suspension add barium chloride and keep stirring for 1-4 hours and Then the suspension is filtered and washed pasta from cm is Oh clay, - plastificated and formed into pellets screw granulator at a pressure of 35-45 ATM and a temperature of 100-120oC. These granules are dried at a temperature of 60-90oC for 10-15 hours, crushed, sieved fraction 1-2 mm, and conducting heat treatment at 200-250oC in a fluidized bed. The catalyst composition, %:

manganese dioxide - 40-60

the barium hydroxide - 30-50

bentonite clay - 5-15

The invention is illustrated by examples.

Example 1.

In a mixer equipped with a mixing device, pour 5 liters of water, include a mixing device and load 3 kg of a paste of manganese dioxide with a humidity of 50%. Mixing lead 30 min until a homogeneous aqueous suspension of manganese dioxide. Then in a mixer add 0.4 kg of sodium hydroxide and continue stirring for 0.5 hours After dissolution of sodium hydroxide without mixing, in a mixer, gradually add 1.5 kg of barium chloride. After the addition of barium chloride to continue the stirring for 2 hours After mixing, the paste is a mixture of manganese dioxide and barium hydroxide is filtered and washed off of Cl-. The resulting paste with a moisture content of 50% in the amount of 6 kg load in a paddle mixer, equipped with provc to a moisture content of 30%. On screw granulator through a Spinneret hole diameter of 1.1 mm is formed into pellets at a pressure of 40 ATM and a temperature of 105oC. These granules are dried at a temperature of 80oC for 12 hours the Dried granules are crushed, sieved fraction 1 - 2 mm, and conducting heat treatment in a fluidized bed with air at a temperature of 300oC. the resulting catalyst has the following composition, %:

manganese dioxide - 50

the barium hydroxide - 40

binder (bentonite clay) - 10

Catalytic activity in the recovery of oxides of nitrogen amounted to 70 g/L.

Example 2

The process, as in example 1, except mixing time after the addition of barium chloride, which amounted to 1 h the resulting catalyst has a composition, as in example 1. Catalytic activity in the recovery of nitrogen oxides was 65 g/l

Example 3

The process, as in example 1, except the amount added to the mixer caustic soda, which amounted to 0.7 kg, the amount added to the mixer of barium chloride, which was 2.0 kg mixing time after the addition of barium chloride, which amounted to 1.5 h, and the amount of the binder is bentonite clay, is added to the paste
manganese dioxide - 40

the barium hydroxide - 48

binder (bentonite clay) - 12

Catalytic activity in the recovery of oxides of nitrogen was 50 g/l

Example 4

The process, as in example 1, except the amount added to the mixer caustic soda, which was 0.3 kg, the amount added to the mixer chloride of barium, which amounted to 1.2 kg mixing time after the addition of barium chloride, which was 3 h, and the amount of the binder is bentonite clay, is added to the pasta mixture of manganese dioxide and barium hydroxide, which amounted to 4.5 kg of the Obtained catalyst has a composition,%:

manganese dioxide - 62

the barium hydroxide - 31

binder (bentonite clay) - 7

Catalytic activity in the recovery of oxides of nitrogen was 60 g/L.

Example 5

The process, as in example 1, except the amount added to the mixer caustic soda, which was 0.8 kg, the amount added to the mixer of barium chloride, which was 2.0 kg mixing time after the addition of barium chloride, which amounted to 4 h, and the amount of the binder is bentonite clay, is added to the paste to shift the AV,%:

manganese dioxide - 39

the barium hydroxide - 56

binder (bentonite clay) - 5

Catalytic activity in the recovery of oxides of nitrogen was 25 g/L.

The study of the influence of the catalyst composition and the time of mixing manganese dioxide with barium hydroxide simultaneously with the preparation of barium hydroxide on the catalytic activity in the recovery of nitrogen oxides in the table.

As the table shows, the highest catalytic activity in the recovery of oxides of nitrogen is observed during the process of mixing manganese dioxide and barium hydroxide simultaneously with the preparation of barium hydroxide at a ratio of [MnO2]:[Ba(OH)2] - 40-60/30-50 wt.% and mixing time 1-4 hours, followed by a mixture of manganese dioxide and barium hydroxide with a binder is bentonite clay. The catalytic activity is lowered by the decrease in the proportion of manganese dioxide less than 40% and the proportion of barium hydroxide is less than 30%. When the reduction of the time of the mixing process less than 1 h, the activity decreases, the increase in time over 4 hours does not increase the catalytic activity.

The proposed method of producing a catalyst for purification of gases from oxides attano during alkaline treatment of a mixture of manganese dioxide with a water-soluble salt of barium within 1-4 h, and then spend a mixture of manganese dioxide and barium hydroxide with bentonite clay in the following ingredients, wt.%:

manganese dioxide - 40-60

the barium hydroxide - 30-50

bentonite clay - 5-15

allows to achieve high quality catalysts intended for the reduction of nitrogen oxides in personal and collective protection of the respiratory organs.

A method of producing a catalyst for purification of gases from nitrogen oxides, comprising a mixture of manganese dioxide with a binder is bentonite clay, the formation of granules, drying, grinding and heat treatment, characterized in that the first aqueous suspension of manganese dioxide is subjected to alkaline treatment simultaneously with the water-soluble salt of barium within 1-4 h, then the resulting paste containing manganese dioxide and barium hydroxide, is mixed with bentonite clay in the following ingredients, wt.%:

Manganese dioxide - 40-60

The barium hydroxide - 30-50

Bentonite clay - 5-15

 

Same patents:

The invention relates to catalytic chemistry, in particular to the preparation of catalysts for Hydrotreating petroleum fractions, and can be used in the refining industry
The invention relates to a process for the preparation of catalysts based on Nickel, stabilized active alumina, for redox processes and can be used in the fine purification of process gases from oxides of carbon, oxygen, and to obtain protective atmospheres by dissociation of ammonia

The invention relates to the production of catalysts for conversion of hydrocarbons

The invention relates to a process for the preparation of carrier catalysts containing silver to obtain ethylene oxide

The invention relates to the preparation of heterogeneous catalysts used in the processes of oxidative chlorination of hydrocarbons

The invention relates to catalytic chemistry, in particular the production of vanadium catalysts for the conversion of SO2in SO3

The invention relates to methods for oxide catalysts

The invention relates to the field of purification of gas emissions into the atmosphere and can be used for purification of exhaust gases from road transport exhaust gases from the spray chambers and other industrial installations, where the vent gas contains harmful organic substances and carbon monoxide

The invention relates to a process for the preparation of catalysts used for the treatment of industrial waste gases containing hydrocarbons and/or carbon monoxide

The invention relates to inorganic chemistry and can be used in particular for the preparation of the catalyst used for purification of gas mixtures of carbon monoxide in the systems of collective and individual protection of respiratory organs and the emissions of industrial enterprises, for purification of exhaust gases of internal combustion engines, as well as for other industrial and environmental purposes

The invention relates to sensitive to the sulfur reforming catalyst that turns into significantly less sensitive to sulfur through the use of a catalytic system comprising a physical mixture of such catalyst and the sulfur absorber selected in order to catch small quantities of sulfur from hydrocarbons

The invention relates to chemistry

The invention relates to the field of environmental protection and can be used for disposal of industrial emissions, mainly in the refining, petrochemical and other industries

The invention relates to a catalyst composition that is used for neutralization of exhaust gases in industry and for carrying out processes of afterburning in the transient mode with heat recovery [1]

Temperature range implementation of these processes 400-1000oWith that determines the requirement for high thermal stability of the catalysts

The invention relates to the production of heterogeneous catalysts for liquid-phase oxidation of sulfide sulfur sulfate white liquor in the polysulfide in the process of getting polysulfide cooking solution and can be used in the pulp and paper industry in the technology of production of cellulose polysulfide method

The invention relates to chemistry, namely the preparation of catalysts for deep oxidation of hydrocarbons

The invention relates to the field of technical chemistry, and in particular to methods of cooking media (systems-precursors for catalysts that can be used in almost any heterogeneous catalytic processes in the chemical industry and in the energy sector, such as catalytic oxidation (full and partial), hydrogenation (including the Fischer-Tropsch synthesis), the conversion of hydrocarbons and other
Up!