Catalyst, catalyst carrier, method of their preparation (options) and the method of purification of waste gases from nitrogen oxides

 

(57) Abstract:

The invention relates to catalysts and method of removal of nitrogen oxides from both dry and wet and sulfur-containing exhaust gas hydrocarbons2-C16in oxidizing conditions. The described catalyst is a composition of composition, wt. %: n Me1m Me2O p SOx/the media, where IU1- noble metal, Me2About - oxide of transition metal, SOx- adsorbed sulfur oxide, n - 3,0 m - not more than 6.0, p is not more than 2.0 in terms of sulphur, and the media is a pillared clay, containing in its composition as columns nanoparticles on the basis of zirconium oxide in the amount of 15-30 wt.% composition x IU3O/ZrO2where IU3O - aluminum oxide, iron, cerium, copper, or their mixture, at x = 0-4,0, or aluminum oxide in the amount of 15-20 wt. %, with interlayer distance not exceeding a total volume of meso - and micropores of no higher than 0.25 cm3/g and a specific surface area of 200-370 m2/, also Described catalyst carrier, method of its preparation, methods of preparation of the catalyst (options) by ion exchange, Votorantim or impregnation. The described method of cleaning exhaust gases from nitrogen oxides from ispoolable hydrocarbons. The technical result is to increase the degree of removal of nitrogen oxides. 9 C. and 11 C.p. f-crystals, 3 ill., table 4.

The invention relates to catalysts and method of removal of nitrogen oxides from both dry and wet and sulfur-containing exhaust gas hydrocarbons2-C16in oxidizing conditions. The catalyst and process are applicable for cleaning any gases that contain nitrogen oxides, including flue gases of thermal power plants, exhaust gases of cars, as well as residual gases in the production of nitric acid.

The process of catalytic purification of exhaust gases from the NOxis the catalytic reduction of nitrogen oxides to molecular nitrogen in excess oxygen in the presence of hydrocarbons. While the hydrocarbons must react selectively with nitric oxide, but not with adsorbed oxygen or oxygen catalyst. The effectiveness of the cleaning process is also determined by the nature of the restorative components in the exhaust gas.

For catalytic purification of exhaust gases from the NOxin the presence of reducing agents (hydrocarbons) with excess oxygen available catalytic systems containing, as a rule, oxides of transition metals: copper, cobalt, Nickel, ID aluminum, the aluminosilicates, Zirconia, or zeolites (M. Iwamoto. Air pollution abatement through heterogeneous catalysis. In Stud. Surf. Sci. Catal. Ed: A. Corma, F. V. Melo, S. Mendioroz, J. L. G. Fierro. Vol. 130A. P. 23-47).

An important advantage of using catalysts based on zeolites is the possibility of obtaining highly dispersed active component that allows you to reduce the amount of catalyst to achieve the required degree of purification. The most active catalyst in the temperature region close to the real temperature of automobile motors, is a catalyst of the type si-ZSM-5 (A. Shichi, K. Katagi, A. Satsuma, T. Hattori. Influence of Intracrystalline Diffusion on the Selective Catalytic Reduction of NO by Hydrocarbon Over Cu-MFI Zeolite. Appl. Catal. B: Environ. 24(2000) 97-105). However, such systems have several significant drawbacks, leading to restrictions on their use, including for a wide range of hydrocarbon reductants:

1. Unwanted receipt of carbon monoxide in the reaction products for a number of catalysts due to incomplete oxidation of hydrocarbons at low temperatures.

2. The presence of the diffusion inhibition when used as a reductant WITH2-C3hydrocarbons due to the presence of channels of 5.4 and 5.6 And in the structure kalinago frame under hydrothermal conditions (in the presence of water vapor), which leads to the destruction of its structure. In addition, there is an interaction so the extra-lattice aluminum in the channels or on the surface of the zeolite crystals with an active component, leading to the formation of surface compounds, significantly less active in the field of low temperatures.

When cleaning car engine exhaust gases during engine operation in a wide range of changing temperature, space velocity, oxygen concentration and the ratio of hydrocarbon/nitric oxide. In addition, the exhaust gases contain water vapor and sulfur dioxide, the latter acts as a catalytic poison. This creates additional demands on the quality of the catalyst:

1. The stability of the active component of the catalyst and the carrier when the temperature changes in a wide range.

2. The stability of the catalyst in the presence of water vapor and sulfur dioxide.

3. No or negligible influence diffusion braking process when working with hydrocarbons, especially those with large carbon chain length.

In this regard, the active ingredient and the carrier for such processes must be thermally stable and resistant to water vapor and dirtie pores (meso - and macropores), allowing to minimize diffusion braking especially when used as reducing agents are hydrocarbons with a large carbon chain length.

Among the new materials of interest as carriers, it should be noted columnar clay - zeolite like structure with high thermal stability and a two-dimensional porous structure. Pillared clays are derived from natural or synthetic clays. Minerals belonging to the group of smectites and their synthetic analogues belong to the layered materials, the layers which form the structure type of sandwich: two outer side layer is formed by tetrahedra-based silicon oxide, between which are octahedral structures or fragments. The General formula of these materials ANDx[M2-3T4ABOUT10(OH)2], where a is the ion-exchange cations in the interlayer space (calcium, sodium), M - octahedral cations (aluminum, magnesium, which can be partially substituted by cations of iron), T - tetrahedral cation (mainly silicon with partial substitution of aluminum or iron).

Pillared clays are obtained by ion exchange between cations compensating the Les cations of Keggin. Subsequent annealing of such systems involving dehydration and dehydroxylization of polyhydroxyamide, leads to the formation of a stable oxide clusters in the interlayer space of the original clay (A. Gil, L. M. Gndia. Rnt dvns in the snthesis and tlti litins of illred lays. tl. Rv-Si. The ENP. 42. 2000. 146-212). Oxide nanoparticles Zr2, TiO2, SiO2, Fe2O3, Al2ABOUT3, GA2ABOUT3or mixed compositions on their basis can be introduced into the interlayer space of clay, the size of which can be the Total amount of micro - and mesopores for pillared clays may be up to 0.25 cm3/,

Meso - and macropores are formed by the docking of fragments of the original clay up to 2 μm, and the micropores are located directly in the interlayer space with two characteristic dimensions: the distance between the clay layers and between the oxide columns. The surface of the columnar clay increases compared to the original clay from 50-100 to 250-400 m2/g, increases thermal stability from 350 to 700oC. cation-exchange properties characteristic of natural clays, hold for pillared clays that allows you to use the method of ion exchange for the introduction of d is the molecular nitrogen hydrocarbons in the presence of excess oxygen on the catalyst based on pillared clays, containing oxides of transition metals, using as a reductant propane (S. rthoner, A. Vri. tlsts sd op illrd Interlrd ls for th Sltive taltic Rdution of NO. l inerals 32 (1997) 123-134) and ethylene (R. T. ADF, M. hriwttnnnn, R. Q. Lng. IEP-hngd illrd ls for Sltiv talti Rductin of NO by Ethlene in the rsn of OHADA. lid tlsis In: nvironmenntal 19. 1998. 289-304).

So, for pillared clays with posts on the basis of Al2O3and mixed Fe-Al oxide systems containing 2-3 wt.% CiO, the maximum conversion of nitrogen oxide and propane does not exceed 10% in the temperature range of 500-550oWhen the composition of the purified gas: 0,08% NO, 0,32%3H8, 2% O2and when flow rate 10000 h-1.

When used as a reductant of ethylene in the composition of the purified gas is 0.1% NO, 0.1% OF C2H4, 2% O2and space velocity of the mixture 21000 h-1the maximum conversion of nitric oxide to nitrogen is 55% at 300oFor columnar clay-based oxide columns of Tio2containing 7.4 wt. % CuO. The introduction of such columnar clay in addition to copper oxide of 0.5 wt. % CE2ABOUT3conversion of nitric oxide increases to 60% at 300oC. When an introd 60 to 53-55% at 300oC. under similar conditions on the catalyst cu-ZSM-5, containing 4.3 wt.% CiO, the conversion of nitric oxide decreases from 45 to 27-30% at 350oC.

Closest to the claimed technical substance is a catalyst and method for the recovery of nitric oxide in oxygen excess in the presence of ethylene on copper-containing pillared clays prepared on the basis of oxide clusters zirconium (R. T. ADF, N. hriwttnnnn, R. Q. Lng. IEP-hngd illrd ls for Sltiv talti Rductin of NO by Ethlene in the rsn of OHADA. lid tlsis In: nvironmenntal 19. 1998. 289-304). In this method for the preparation of pillared clays using bentonite. Synthesis of Zr-containing pillared clay is carried out by adding Intercollege solution prepared by aging of zirconium oxychloride (with a concentration of 0.1 M) at pH of about 1.3 for 3 days in a bentonite suspension (2 wt.% on solid matter) content 5 mmol Zr/g of clay, followed by aging the suspension at room temperature for 3 days. Then the precipitate is filtered off, washed with water, dried and calcined at 350oWith 12 hours. You get a clay bar surface 195 m2/g, volume of meso - and micropores of 0.14 cm3/g and the interlayer distance

and pH 6 and a temperature of 50oC. Then the precipitate is filtered off, washed with water, dried at 120oC for 12 hours and calcined at 400oWith, result in a catalyst containing 3.7 wt.% SiO. When the composition of the purified gas with 0.1% NO, 0.1% OF C2H4, 2% O2and space velocity of the mixture 21000 h-1the maximum conversion of nitric oxide in nitrogen at a temperature of 350oWith this catalyst 46.4%.

Pillared clay-based columns of aluminum oxide obtained when internalrevenue 1% suspension of bentonite (10 mmol Al/g clay) with a solution of aluminium chloride with respect, HE/Al=2.0 and pH 4.2, obtained by aging for one day of a mixture of solutions of 0.2 M ll3and 0.1 M Paon. The suspension is incubated at room temperature for 24 hours. The precipitate is then separated from the solution by vacuum filtration and washed with water until the lack floridino, dried and calcined at 350oWith 12 hours. Application of copper oxide is conducted in a similar manner as for zirconium bearing columnar clay. For pillared clays prepared on the basis of columns of alumina and containing 4.8 wt. % CuO, the maximum conversion of nitric oxide in nitrogen at a temperature of 350oWith this catalyst composed of layered materials of the group of smectites, and, in particular, montmorillonite and bentonite, by introducing oxide nanocolumn aluminum or zirconium in the interlayer space of the layered clay, in the latter case, containing oxides of aluminum, or iron, or cerium, or copper. Columnar clay used in this invention as carriers for the preparation of catalysts containing the oxides of copper and cobalt, or a mixture of the noble metal and the adsorbed SOx. The media can be used in the form of a powder or molded in the form of a cylindrical shanks, rings of different diameter and thickness or blocks cell structure.

The invention solves the problem of efficient removal of nitrogen oxides from both dry and wet and sulfur-containing exhaust gases (sulfur oxides are catalytic poison) at low temperatures by using a wide range of hydrocarbons as a reductant WITH2-C16.

The task is solved by a catalyst for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere containing in its composition columnar clay, which is a composition of composition, wt. %: n IU1m IU2O R SOx/the media, where IU<- not more than 3.0, m - not more than 6.0, p is not more than 2.0 in terms of sulphur, and the media is a pillared clay, containing in its composition as columns nanoparticles on the basis of zirconium oxide in the amount of 15-30 wt.% composition: x IU3O/Zr2where IU3O - aluminum oxide, iron, cerium, copper, or their mixture, at x=0-4,0, or aluminum oxide in the amount of 15-20 wt. %, with interlayer distance not exceeding a total volume of meso - and micropores of no higher than 0.25 cm3/g and a specific surface area of 200-370 m2/,

As the noble metal catalyst contains silver, platinum, palladium or a mixture thereof, as an oxide of the transition metal it contains copper oxide, cobalt or a mixture, as of adsorbed sulfur oxide it contains the product of the decomposition of sulfuric acid, or sulfur, or solfataras ammonium salt.

The task is also solved by a carrier catalyst comprising a pillared clay, containing in its composition as columns nanoparticles on the basis of zirconium oxide in the amount of 15-30 wt.% composition: x IU3O/ZrO2where IU3O - aluminum oxide, iron, cerium, copper, or their mixture, at x=0-4,0, or aluminum oxide in the amount of 15-20 wt.%, with the interlayer distance is not above ovset a powder, or cylindrical cuttings, or rings of different diameter and thickness, or blocks of honeycomb structure.

The task is also solved by a method of preparation of the catalyst carrier by reacting the starting components containing natural or synthetic clay from the group of smectites, while the use of aluminum compounds or zirconium, followed by the separation of the precipitate from the solution, washing with water, drying and calcination. In the preparation of media use freshly prepared or have been subjected to aging 2-30 hours at a temperature of 20-100oWith solutions containing zirconium compounds, or salt of alkaline earth metal, or aluminum, or iron, or cerium, or copper, or a mixture.

For solving the problem have also been developed variants of the method of preparation of the catalyst or by fotogaleria compound of the noble metal on the above carrier, or by ion exchange salt of copper or cobalt and fotogaleria compound of the noble metal on the carrier, or by fotogaleria salt of copper or cobalt and compounds of the noble metal in the presence of a1-C10alcohols to the media.

The catalyst is prepared by impregnation on capacity salt midlateral ammonium salt and the compound of the noble metal of the above media, represents a column of clay.

The purpose of the efficient flue gas cleaning (both dry and wet and sulfur) from nitrogen oxides is solved by catalytic reduction with hydrocarbons2-C16in an oxidizing atmosphere in the presence of the above catalyst based on pillared clay at a temperature 180-560oC.

When using the catalyst in powder form or by drawing on a cell block of metal or ceramic substrates, solid granules, rings and blocks with the addition of binders based on silicates, hydroxides of aluminum, Sol oxyhydroxide zirconium-containing cerium or alkaline earth metal.

Examples 1-14 illustrate the preparation of a carrier.

As a source of clay can be used minerals from the group of smectites include montmorillonite or bentonite composition M[(Al(MD, Fe)(Si4O10)(OH)2z2Oh, where M is ionomine cations PA or Sa; Al(MD, Fe) - which are octahedrally coordinated cations, mg, and Fe isomorphically substitute aluminium cations in the lattice; the silicon cations are located in the tetrahedra (the text uses different structural formulas of clay). The General scheme of the preparation, the process of pre-milled original clay hydration in aqueous solution. For the preparation of pillared clay using the fraction less than 2 μm, which is formed from the suspension after settling of larger particles for 0.5 hours.

2) Preparation Intercollege solution. Preparation of salt solutions based on aluminium chloride or zirconium salt, allowing you to get the polycation composition [Al13O4(OH)24(H2O)12]7+or oligomers based on the [Zr4(OH)8(H2O)16]8+in the latter case, consistent with the formation of the products of its hydrolysis and polymerization in the particles of larger size during aging solutions and/or the introduction of salt, alkaline earth metal, or aluminum, or cerium, or iron, or copper.

3) the Intercalation of the clay. Mixing suspensions of montmorillonite or bentonite clay with intercalaris solution for a time and at a temperature sufficient for the formation of the intermediate columnar clay.

4) the sludge Separation of the intermediate columnar clay from the solution by the method of decantation, or centrifugation, or filtration.

5) Washing the precipitate from the excess of cations and anions using the multiple decantation, or centrifugation, or filtrowanie or pre-molded in the form of a cylindrical shanks, rings of different diameter and thickness or blocks cell structure.

Characterization of clays are given in table 1. The specific surface thus prepared pillared clays after calcinations at 500oC is 200-350 m2/g pore Volume for pillared clays may be up to 0.25 cm3/g with approximately equal contribution of meso- (about ) and micropores (about ).

Example 1. Prepared suspensions of clay.

12 g PA-forms of montmorillonite is dried in a drying Cabinet at 120oWith 10 hours to a residual moisture content of 10 wt.%. Receive the portion 11 g (or 10 g of absolutely dry matter). On the basis of the obtained sample dried clay preparing a suspension in an aqueous solution under stirring at a ratio of clay: water=1:10. Clay hydrated for 12 hours. Then stop stirring and after 0.5 hours after the sedimentation of large particles selected homogeneous upper part of the suspension containing particles less than 2 microns. The resulting suspension can be concentrated by the method of decanting to 20 wt.%. on solid matter.

Preparation Intercollege solution. In a solution of aluminium chloride (0.24 M) was injected a solution of sodium hydroxide to the ratio IT/Al=2,3, the pH of the resulting suspension of clay (10 wt.% clay) enter 300 ml of 0.1 M Intercollege solution (3 mmol of aluminum per gram of clay). The final concentration of clay in suspension of 2.5 wt.%. The resulting suspension is stirred at room temperature for 24 hours.

The precipitate formed after cessation of mixing, is intermediate columnar clay, it is rinsed from the original solution by the method of repeated decantation, to lack of test reactions to chlorine using a salt of silver nitrate.

The obtained intermediate columnar clay dried at 60oC for 18 hours and then formed into a cylindrical shanks with a diameter of 3 mm Final temperature annealing 500oWith 6 hours.

Thus obtained columnar clay containing 15.0 wt.% Al2ABOUT3(media 1).

Example 2. Preparation of suspension of the clay of example 1.

Preparation Intercollege solution. In a freshly prepared solution of zirconium oxychloride (0.1 M, pH 1,25) introducing a portion of the hydrated calcium chloride in an amount such that the molar ratio of zirconium, calcium was equal to 9.2:1,0. Then spend the aging of the solution at 60oWith 18 hours.

The intercalation of the clay. To 217 ml of a suspension of clay (10 wt.% clay) within 3 hours of dosing under stirring 220 ml interchannel the suspension is incubated at 60oWith 18 hours.

The separation of the intermediate columnar clay and washing from the original solution by filtration method. The resulting product is dried at 60oC for 18 hours and then formed into a cylindrical shanks with a diameter of 3 mm Final temperature annealing 500oC for 6 hours.

Prepared in this way columnar clay contains of 18.5 wt.% ZrO2(media 2).

Example 3. Preparation according to example 2 with the difference that the molar ratio of zirconium:calcium in the intercalating solution is 1:1.

Prepared in this way columnar clay contains 20.0 wt.% ZrO2(media 3).

Example 4. Preparation according to example 2 with the difference that instead of calcium chloride is used as strontium chloride.

Prepared in this way columnar clay contains 18,8 wt.% ZrO2(media 4).

Example 5. Preparation according to example 2 with the difference that instead of calcium chloride using barium chloride.

Prepared in this way columnar clay contains of 18.5 wt.% ZrO2(media 5).

Example 6. Preparation of a suspension of clay in example 1 with the difference that instead of the PA-form montmorillonite Jenny solution of zirconium oxychloride (0.1 M) type crystals of cerium nitrate (molar ratio of zirconium:CE=1:0,5), the pH of the solution of 1.48. The addition of sodium hydroxide the pH of the solution increased to 2.27, followed by aging the solution at 60oWith over 14 hours (final pH value of 1.47).

The intercalation of the clay. 200 ml of a suspension of clay (10 wt.% clay) within 8 hours of dosing 240 ml Intercollege solution. The ratio of zirconium: clay is 2.4 mmol of zirconium per gram of clay. The resulting suspension was kept at 60oC for 15 hours. Washing clay carried out by the method of decanting. Further preparation of example 1.

Prepared in this way columnar clay contains, wt%: 0.03% SEO2, 23,0% ZrO2(media 6).

Example 7. Preparation Intercollege solution. In the solution of zirconium oxychloride (0.36 M) enter solution of cerium nitrate (0.02 M) to the molar ratio of the zirconium:CE=1:0,2, then the solution is maintained at 60oC for 16 hours (pH 1,15). Further, the preparation according to example 2.

Prepared in this way columnar clay contains, wt%: 0.03% SEO2, 20,0% ZrO2(media 7).

Example 8. Preparation Intercollege solution. In the solution of zirconium oxychloride (0.36 M) enter solution of cerium nitrate (0.05 M) to the molar ratio of the zirconium:CE=1>/P>Prepared in this way columnar clay contains, wt%: 0,07% SEO2, 20,0% ZrO2(media 8).

Example 9. Preparation Intercollege solution of example 8 with the difference that the intercalating solution maintained at 60oC for 16 hours and additionally at room temperature for 16 hours. Further preparation is conducted according to example 2.

Prepared in this way columnar clay contains, wt%: 0,07% SEO2, 20,0% ZrO2(media 9).

Example 10. Preparation Intercollege solution. In the solution of zirconium oxychloride (0.36 M) enter solution of ferric chloride, the molar ratio of zirconium:iron=1:0,5. Thus obtain a solution of 0.1 M zirconium at pH of 1.41, which is subjected to aging at 60o16 hours, the final pH of the solution is to 1.15. Further preparation is conducted according to example 2.

Prepared in this way columnar clay contains, wt%: 0,86% Fe2ABOUT3, 20,0% ZrO2(media 10).

Example 11. The preparation is conducted according to example 10 with the difference that in the preparation of Intercollege solution to increase the pH of the introduction of sodium hydroxide to a pH of 2 and then subjected to aging. Next UB>2ABOUT3, 20,0% ZrO2(media 11).

Example 12. The preparation is conducted according to example 10 with the difference that in interkaliruyut solution the molar ratio of the zirconium metal is 1:0,2.

Prepared in this way columnar clay contains, wt%: 0,86% Fe2ABOUT3, 20,0% ZrO2(media 12).

Example 13. The preparation is conducted according to example 10 with the difference that in the preparation of Intercollege solution using the ratio of zirconium, iron, equal to 1:0,67, and for internalrevenue clay uses the ratio of zirconium:clay, equal to 1.6 mmol per gram of clay.

Prepared in this way columnar clay contains, wt%: 1,40 Fe2ABOUT3, 15,0 ZrO2(media 13).

Example 14. In a solution of acetate of Zirconia (solution in dilute acetic acid, ldrich 41 380-1) 0.18 M, soaked 2 hours at room temperature, add a solution of aluminium chloride 0.1 M, prepared as described in example 1. The ratio of zirconium:aluminum is 2:1, the pH of the mixture solutions of 4.05. Thus prepared intercalary solution is metered in over 3 hours at room temperature to a suspension of clay. The final ratio of zirconium: clay is 2 mmol/tsentrifugirovaniem followed by washing of the precipitate to the lack acetaminoph. Drying, molding and calcination as in example 1.

Prepared in this way columnar clay contains, wt%: 4,0% Al2O3, 15,0% ZrO2(media 14).

Examples 15-29 illustrate the preparation of catalysts.

The proposed catalysts were tested in the recovery process NRxin the presence of propane, propylene or Dean in an oxidizing atmosphere. Testing is carried out in a flow reactor, in which load the required amount of catalyst and with a certain volumetric rate serves the gas to be cleaned.

The reaction products analyzed by gas chromatography or by using IR and chemiluminescent analyzers. The effectiveness of the cleaning process is characterized by the degree of conversion of NOxin N2. For catalysts for the selective conversion of nitric oxide in the presence of propane and propylene also determine the conversion of hydrocarbons to carbon oxides.

Tested in the reaction of catalytic reduction of NO by propane in excess of oxygen is carried out at the composition of the purified gas: 0,1% vol. NO, 0,13% WITH3H6, 1,0 vol.% O2the rest up to 100% helium at flow rate 12500 h-1.

Ispitania gas: 0.2 vol% NO, 0,2% vol. WITH3H6, 2,5 vol.% O2the rest up to 100% nitrogen at flow rate 18000 h-1. Testing of the catalysts used for dosing in the composition of the purified gas catalytic poisons: water vapor and sulfur dioxide, is carried out at the composition of the initial mixture: 0,15% NO, 0,14% vol. WITH3H6, 1% vol. ABOUT2, 3% vol. H2O 0,01% vol. SO2and when flow rate 70000 h-1.

Testing process of removal of nitrogen oxides by the Dean in excess of oxygen is carried out at the composition of the purified gas: 0,15% NO, 0,05% vol. WITH10H22, 7% vol. ABOUT2the rest up to 100% nitrogen at flow rate 11250 h-1. Testing of the catalysts used for dosing in the composition of the purified gas catalytic poisons: water vapor and sulfur dioxide, is carried out at the composition of the initial mixture: 0,15% NO, 0,05 about. %10H22, 7% vol. ABOUT2, 3% vol. H2O 0,01% vol. SO2the rest up to 100% nitrogen at flow rate of 40,000 hours-1and 70000 h-1.

Below are examples illustrating the change in performance of the cleaning process from the NOxdepending on the process conditions (reaction temperature, the type of hydrocarbon, the composition of the gas during cleaning), the nature of the catalysts and methods for their preparation. Main Haritonov of examples 20 and 26, 28-29 the data on trials in dry mixtures, and containing water vapor and sulfur dioxide.

Example 15. 10.0 g of powdered media 3 impregnate on capacity 6.5 ml of a solution of nitrate of copper, containing 0,0573 g C/ml Then the powder is dried under IR lamp for 10 hours and calcined at 400oWith 2 hours. The composition of the catalyst corresponds to the formula, wt.%: 4.6% of CuO/media 3.

Example 16. 1,141 g of copper nitrate dissolved in 100 ml of distilled water in a quartz glass. In the solution with stirring enter 5 g powder carrier 4. After 0.5 hours include mercury vapor lamp type DRL-250, the radiation of which is directed at the glass, the distance between the lamp and the glass is 5 see the Suspension of the carrier in a solution of copper nitrate are mixed under the action of UV/visible light for 2 hours. Then the precipitate is filtered off and washed with four volumes of water. The precipitate is dried under an infrared lamp and calcined at 400oWith 2 hours.

5 g of powder coated with copper oxide under stirring injected into 100 ml of a solution containing 0.015 g PT (H2tl6), quartz glass. After 0.5 hours include mercury vapor lamp type DRL-250, add 0.45 ml of methanol and the contents of the glass mix the od IR lamp and calcined at 400oC for 2 hours.

The composition of the catalyst corresponds to the formula wt. %: 0,23% PT, 1.5% of CuO/media 4.

Example 17. Sample get analogously to example 15 with the difference that instead of the nitrate of copper use 1,478 g of cobalt nitrate. The composition of the catalyst corresponds to the formula, wt.%: 0.26% of PT, 0.30% of COO/media 4.

Example 18. The sample was prepared as in example 15 with the difference that the use of carrier 2. The composition of the catalyst corresponds to the formula, wt.%: 0,25% PT, 1.5% of CuO/media 2.

Example 19. The sample was prepared as in example 15 with the difference that the use of carrier 5. The composition of the catalyst corresponds to the formula, wt.%: 0,23% PT, 1.8% Of CuO/media 5.

Example 20. 25 g of the cylindrical shanks (diameter 3 mm) media 6 pour 250 ml of a solution of nitrate of copper (0.9 M) and then heated at 50oWith in 48 hours. The sample was then filtered off, washed with water, dried at 100oWith 10 hours and calcined at 400oWith 6 hours.

5 g of the fraction <2 mm after application of copper oxide impregnated on the capacity of 3.4 ml of silver nitrate solution containing 0.05 g of silver. The sample is dried at 100oWith 10 hours and calcined at 400oWith 6 hours. The composition of the catalyst corresponds to the formula, wt.%: 1,0% Hell 4,0% CIO/is from this catalyst when cleaning dry (curve 1) and containing water vapor (3%) and sulfur dioxide (0,01%)(curve 2) exhaust gases in the presence of a reducing agent - propylene at flow rate 11250 h-1and the following composition of the original mixture: 0,15% NO, 0,14% vol. WITH3H6, 1% vol. ABOUT2the rest is nitrogen. It is seen that although the presence of water vapor and sulfur dioxide reduces the conversion of nitric oxide, but stable level of activity more than 50% is maintained in a wide temperature range 300-520oC.

Example 21. The sample was prepared as in example 15 except that 8 g of the powder of the carrier 7 is introduced into 150 ml of a solution containing 1,510 g of copper acetate. For applying platinum 4 g powder coated with copper oxide is introduced into a solution containing 0,012 g PT (H2tl6). The composition of the catalyst corresponds to the formula, wt.%: 0,30% PT, 1.8% Of CuO/medium 7.

Example 22. The sample was prepared as in example 20 with the difference that for making use of the carrier 12.

Example 23. 25 g of the cylindrical shanks (diameter 3 mm) media 1 pour 250 ml of a solution of nitrate of copper (0.9 M) and then heated at 50oWith in 48 hours. The sample was then filtered off, washed with water, dried at 100oWith 10 hours and calcined at 400oWith 6 hours.

5.29 g of powdered sample coated with copper oxide are introduced with stirring into 100 ml of a solution containing 0.76 to remediat under the action of UV/visible light for 0.5 hours. Then the precipitate is filtered off, washed with water, dried under an infrared lamp and calcined at 400oC for 2 hours. The composition of the catalyst corresponds to the formula, wt.%: 2.6% of the Hell, 5.7% of CuO/media 1.

Example 24. The sample was prepared as in example 20 with the difference that for making use of the carrier 8. The composition of the catalyst corresponds to the formula, wt.%: of 0.3% PT, 1.7% of CuO/media 8.

Example 25. The sample was prepared as in example 20 with the difference that for making use of the carrier 9. Cooking only restrict the application of copper oxide. The composition of the catalyst corresponds to the formula wt. %: 1.8% CuO/media 9.

Example 26. The sample was prepared as in example 20 with the difference that for making use of the carrier 10. The composition of the catalyst corresponds to the formula, wt.%: 0,30% PT, 1.8% Of CuO/medium 10.

In Fig. 2 shows the temperature dependence of the conversion of nitric oxide to molecular nitrogen for this catalyst when cleaning dry (cu.1) and containing water vapor (3%) and sulfur dioxide (0,01%) (CR.2) the exhaust gases in the presence of a reducing agent - the Dean at flow rate 11250 h-1when the composition of the purified gas: 0,15 about. % NO, 0,05% vol. WITH10H22, 7% vol. O2the rest up to 100% nitrogen. It is seen that in prituri. In the field of medium temperature conversion is reduced, but remains relatively high, more than 50%, significantly increases the conversion of nitric oxide in the region of low and high temperatures.

Example 27. The sample was prepared as in example 20 with the difference that for making use of the carrier 11. The composition of the catalyst corresponds to the formula, wt.%: of 0.3% PT, 1.8% Of CuO/media 11.

Example 28. The sample was prepared as in example 20 with the difference that for making use of the carrier 13 and when applying the copper oxide in a solution of copper acetate to impose an additional 10 ml of isopropyl alcohol. The composition of the catalyst corresponds to the formula, wt.%: of 0.3% PT, 1.8% Of CuO/media 13.

In Fig. 3 shows the temperature dependence of the conversion of nitric oxide to molecular nitrogen in dry cleaning (cu.1) and containing water vapor (3%) (CR. 2) the exhaust gases in the presence of a reducing agent - the Dean at flow rate 11250 h-1when the composition of the purified gas: 0,15% NO, 0,05% vol. WITH10H22, 7% vol. ABOUT2the rest up to 100% nitrogen. It is seen that in the presence of vapor decreases the conversion of nitric oxide in the range of medium temperatures, but remains relatively high at low and high temperatures.

Example 29. of 5.40 g phoroshop is OK dried at room temperature, then under IR lamp for 10 hours and calcined at 500oWith 1 hour. Thus prepared powder soaked in water holding capacity of 3.8 ml of a solution containing dCl2(based on 0,0054 g PD) and H2tl6(0,0055 g PT). The powder is dried at room temperature, then under IR lamp for 10 hours and calcined at 400oWith 2 hours. The composition of the catalyst corresponds to the formula, wt.%: 0,1 PT; 0,1 PD; SOx(1,4% 8)/the carrier 14.

Thus, as seen from the above examples, the proposed catalysts can effectively remove nitrogen oxides from both dry and wet and sulfur-containing exhaust gases at low temperatures by using a wide range of hydrocarbons as the reductant.

1. The catalyst for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere containing in its composition columnar clay, characterized in that it is a composition of composition, wt.%: n Me1m Me2O p SOx/ the media, where: IU1- noble metal, Me2O - transition metal oxide, SOx- adsorbed sulfur oxide, n - 3,0 m - not more than 6.0, p is not more than 2.0 in terms of sulphur and wear the ove of zirconium oxide in the amount of 15-30 wt.% composition x IU3O/ZrO2where IU3O - aluminum oxide, iron, cerium, copper, or their mixture, at x = 0-4,0, or aluminum oxide in the amount of 15-20 wt.%.

2. The catalyst p. 1, characterized in that the columnar clay has an interlayer distance not exceeding the total amount of meso - and micropores of no higher than 0.25 cm3/g and a specific surface area of 200-370 m2/,

3. The catalyst according to any one of paragraphs.1 and 2, characterized in that the noble metal it contains silver, platinum, palladium or a mixture thereof.

4. The catalyst according to any one of paragraphs.1-3, characterized in that as the oxide of the transition metal it contains copper oxide, cobalt or a mixture thereof.

5. The catalyst according to any one of paragraphs.1-4, characterized in that the quality of adsorbed sulfur oxide it contains the product of the decomposition of sulfuric acid or sulfur - or solfataras ammonium salt.

6. The carrier of the catalyst for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere, representing columnar clay, containing in its composition as columns nanoparticles based on metal oxide, characterized in that as the oxide of the metal it contains zirconium oxide ¾ mixture, when x = 0-4,0, or aluminum oxide in the amount of 15-20 wt.%.

7. Media under item 6, characterized in that it is a pillared clay with interlayer distance not exceeding a total volume of meso - and micropores of no higher than 0.25 cm3/g and a specific surface area of 200-370 m2/,

8. The carrier according to any one of paragraphs. 6 and 7, characterized in that it is a powder or cylindrical cuttings, or rings of different diameter and thickness, or blocks of honeycomb structure.

9. The method of preparation of the catalyst carrier for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere by reacting the starting components containing natural or synthetic clay from the group of smectites, characterized in that the use of aluminum compounds or zirconium, followed by the separation of the precipitate from the solution, washing with water, drying and calcination, you get a carrier according to any one of paragraphs.6-8.

10. The preparation method of the carrier under item 9, characterized in that the use of freshly prepared or have been subjected to aging 2-30 hours at a temperature of 20-100oWith solutions containing zirconium compounds.

11. The method of preparation nologo metal or aluminum, or iron or cerium, or copper or a mixture, you get a carrier according to any one of paragraphs.6-8.

12. The method of preparation of the catalyst for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere, characterized in that the catalyst is prepared by fotogaleria compound of the noble metal on the carrier, representing columnar clay, according to any one of paragraphs.6-8 will get a catalyst according to any one of paragraphs. 1-5.

13. The method of preparation of the catalyst for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere, characterized in that the catalyst is prepared by ion exchange salt of copper or cobalt and fotogaleria compound of the noble metal on the carrier, representing columnar clay, according to any one of paragraphs.6-8 will get a catalyst according to any one of paragraphs.1-5.

14. The method of preparation of the catalyst for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere, characterized in that the catalyst is prepared by fotogaleria salt of copper or cobalt and compounds of precious metals in Pris is this get the catalyst according to any one of paragraphs.1-5.

15. The method of preparation of the catalyst for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere, characterized in that the catalyst is prepared by impregnation on capacity salt of copper or cobalt, or a compound of a noble metal carrier representing a column of clay, according to any one of paragraphs.6-8 will get a catalyst according to any one of paragraphs.1-5.

16. The method of preparation of the catalyst for purification of exhaust gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere, characterized in that the catalyst is prepared by impregnation of capacity with an aqueous solution of sulfuric acid or sulfur - or solfataras ammonium salt and the compound of the noble metal carrier representing a column of clay, according to any one of paragraphs.6-8 will get a catalyst according to any one of paragraphs.1-5.

17. The method of purification of waste gases from nitrogen oxides by the catalytic recovery of hydrocarbons in an oxidizing atmosphere in the presence of a catalyst based on pillared clay at a temperature 180-560o, Characterized in that the use of the catalyst according to any one of paragraphs.1-16.

19. The method according to any of paragraphs.17 and 18, characterized in that conduct cleaning both dry and wet and sulfur-containing exhaust gases.

20. The method according to any of paragraphs.17-19, characterized in that the use of catalyst in powder form, or by drawing on a cell block of metal or ceramic substrates, solid granules, rings and blocks with the addition of binders based on silicates, hydroxides of aluminum, Sol oxyhydroxide zirconium-containing cerium or alkaline earth metals.

 

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