The catalyst for purification of exhaust gases with excess oxygen from nitrogen oxides, method thereof and method of cleaning exhaust gases

 

(57) Abstract:

The invention relates to catalysts for efficient removal of nitrogen oxides from waste gases with a high content of oxygen, the method of producing catalysts and the method of purification of waste gases from nitrogen oxides. Described is a catalyst for purification of exhaust gases with excess oxygen from oxides of nitrogen, including the active ingredient, a carrier of glass fiber material, in which the media use fiberglass cloth from silicate glass, leached to the content of silicon dioxide of 90.0 to 99.9 wt.% and having a specific surface area of 0.2-7.0 m2/g, as the active component, the catalyst contains at least one metal from the platinum group in the amount of 0.001 to 0.3 wt.% and further comprises a promoter, representing a combination of at least one element or more elements from the group comprising aluminum, iron, silicon, titanium, cerium, lanthanum, molybdenum and/or their oxides in a quantity of 0.001-0.5 wt.%, and has the following composition, wt. % in terms of metal: platinum group metal, 0.001 to 0.3, the promoter of 0.001 to 0.5, a carrier of the rest. Also described is a method of obtaining a catalyst and method of cleaning exhaust gases neenie activity selectivity, chemical and thermal stability of the catalyst. 3 S. and 9 C.p. f-crystals, 4 Il., table 2.

The invention relates to catalysts for efficient removal of nitrogen oxides from waste gases with high oxygen content and a method for producing a catalyst, characterized by a high degree of purification, selectivity, chemical and thermal stability. The proposed catalyst is applicable for any cleaning gas containing nitrogen oxides in oxygen excess, including the exhaust gases of diesel and petrol engines, flue gases from a power plant and exhaust gases from the nitric acid production.

Catalytic purification of nitrogen oxides from exhaust gases of diesel, gasoline and turbine engines is a very important task, which is associated with the strengthening of sanitary norms. A positive solution to this problem is complicated by the very harsh conditions of the catalysts, especially in the case of diesel engines: wide temperature range, high oxygen content, the presence of water, serosoderjaschei compounds that have, as you know, a strong deactivating effect.

For purification of exhaust gases from nitrogen oxides in an oxidizing atmosphere ispolzuemoe recovery of hydrocarbons.

For selective catalytic reduction of nitrogen oxides by ammonia known catalysts in which the active component is used, the oxides of vanadium, titanium, etc. printed on various media. Thus, in U.S. patent 5155083 (IPC B01J 21/06, B01J 21/08, 1992) for the catalytic purification of exhaust gases from nitrogen oxides by reduction with ammonia proposed catalyst using inorganic fibers. The fabric of the silicate glass is treated with mineral acid to form a layer on it with lack of aluminum oxide and alkaline earth metals, washed, dried and put a suspension comprising an organic binder (polyvinyl alcohol), silica and a catalytic composition comprising at least one oxide from the group of oxides of titanium, vanadium, molybdenum, tungsten, followed by drying and heat treatment. The mass ratio between applied oxides and glass carrier is 0.05 to 0.8, i.e. the content of deposited oxides is quite large (5-45 wt.%) and the method of synthesis is selected so that the applied particles 700-900 And located in the spaces between the fibers of the fiberglass.

The disadvantage of this catalyst is not what the op leads to flaking and possible mechanical entrainment flow of the purified gas. In addition, in this invention as the reductant is ammonia, which is toxic and uncomfortable in the work connection, and this process is mainly used for purification of exhaust gases of stationary installations. When cleaning the exhaust gases of vehicles as a reducing agent it is better to use hydrocarbons (HC) in accordance with the reaction:

NOx+ NA + O2--> N2+ CO2+ H2O (1)

For the process of reduction of nitrogen oxides by hydrocarbons used catalysts based on metals of group VIII, as well as base metals, deposited on a zeolite or an oxide media of different composition.

Thus, in U.S. patent 5211010 (IPC F01N 3/02, 3/22, 1993) to remove oxides of nitrogen from exhaust gases of diesel engines suggest the use of a catalyst, in which the media use zeolite as active component is a transition or rare metals. The restoration of NOxon zeolite catalysts is characterized by high selectivity for nitrogen, i.e., the absence or low content in the converted mixture of unwanted side products N2Oh and NO2formed according to the reactions:

NO + H2ABOUT (3)

The disadvantage of zeolite catalysts is relatively high temperatures of the beginning of the reaction (usually above 340-400oC). In addition, the catalyst is deactivated at temperatures above 600oWith, especially in the presence of water, serosoderjaschei compounds present in the exhaust gases. These disadvantages limit the practical application of zeolite catalysts.

For the catalytic reduction of NOxhydrocarbon in excess oxygen known catalysts based on metals of group VIII deposited on oxide carriers. Given the high speed exhaust gas flows, for practical purposes a specific geometric shape of the carriers providing low hydraulic resistance. Thus, the catalyst for purification of exhaust gases of a diesel engine (U.S. Patent 5208203, IPC B 01 J 21/06, 23/56, 23/58, 23/60, 1993) includes as an active component, a metal of group VIII. As the carrier use a ceramic honeycomb or ceramic foam, and metal blocks.

The main disadvantage of these catalysts is that, in addition to nitrogen, a by-product is N2O, formed by the reaction (2). In addition, the reaction vos when the temperature rises above 300oWith mainly flows through the reaction of deep oxidation of hydrocarbons (4), which reduces the conversion of NOx.

NA + O2-->2+ H2ABOUT (4)

Known catalyst for purification of exhaust gases of diesel engines (U.S. Patent 5462905, IPC B01J 21/08, 1995) based on the media of porous silica or silica with other metal oxide having a layered structure. In the media between the individual silicon(metal)-oxygen layers are formed due to Si-O-Si, forming a three-dimensional structure with a specific surface area from 4,400 to 4,500 m2/g, having many pores with a diameter from 10 to Received carrier impregnated with compounds of the catalytically active substances, including noble, transition and rare-earth metals, dried and subjected to heat treatment.

Compared to known for this process, the catalyst Pt/Al2ABOUT3(Fig. 4) on the catalyst temperature of the beginning of the reaction decreases with 240-250 200oC. However, this lowering of the reaction temperature is insufficient for satisfactory operation under conditions of cold start. In addition, the catalyst is not sufficiently selective.

The activity and selectivity of the process could is snasti, the acid properties of the surface. As already mentioned, are important and geometric characteristics of the catalysts: their size and shape. The use of carriers and catalysts in the form of fine fibers and products made of them has obvious advantages over the traditional geometric forms of mechanical, aerodynamic, thermal and physical properties. This is especially important for the processing conditions of the exhaust gases of automobile engines.

In some cases, for such processes, it is suggested to use catalysts, carrier of which are silicate glass fiber materials that are available and have a relatively low cost.

In U.S. patent 4038214 (IPC B01J 23/86, 1977) proposed a catalyst for purification of exhaust gases, in which the media use fiberglass materials, made in the form of mesh fabrics (cell size 3.5-60 mesh) special weaving (from yarns obtained by twisting 2000-10000 pieces of very thin fibers with a diameter of 3-40 μm). This tissue structure provides high resistance to vibration and shock and low hydraulic resistance when working in the catalytic device. To enhance clotting media with high (at least 95%) content of SiO2and a very low content of alkali metals. The catalysts obtained by applying the above mentioned media connection, Ni, Cr, Mn, showed a high degree of purification from CO and hydrocarbons. Their disadvantage is the low activity in the reduction reaction of nitrogen oxides with hydrocarbons and selectivity.

Known vysokoglinozemistyj porous fiberglass products, which have high porosity and high specific surface area (U.S. Patent 4933307, IPC SS 11/00, SS 12/00, 1990; patent EP 1044935, IPC SS 25/66, SS 25/10, 2000). These products are made from aluminosilicate glass by leaching of acids.

However, these products are prone to breaking and cracking. There are attempts to improve their durability in a variety of techniques. Thus, in U.S. patent 4933307 use leaching techniques to increase strength, however, for the preparation of catalysts operating in harsh environments (high temperature, high speed and so on), these products are not suitable.

In the patent EP 1044935 on porous glass with a developed specific surface area of from 10 to 120 m2/g (shallow leaching) and from 60 to 400 m2/g (deep leaching) precipitated additional material, Molochna high surface area cannot be used for the preparation of catalysts for industrial and implementing them because, as noted above, many catalytic processes occur at elevated temperatures and pressures. We offer fiberglass material shows low activity and selectivity, for example, in the purification of exhaust gases of diesel engines.

In the work of centuries of Barilko (Century. Century. Barelko and other Catalytic systems on the basis of fiberglass amorphous matrices doped with metals and their oxides, the reduction of nitrogen oxides. //Reports Of The Academy Of Sciences. - 1998. , 361, 4, - S. 485-488) in the leached glass by an ion exchange method was introduced various catalytic components, including precious metals. Catalysts containing 0.1-0.2% of Pt and Pd were tested in the reduction reaction of NOx with propane in the presence of oxygen (model blend composition of 0.25% NO+0,24% C3H8+4,5% O2rest N2), as well as in the absence of oxygen. If in the absence of oxygen on the catalyst has a high conversion of NO at 200-300oSince, in the presence of oxygen all studied catalysts were not very active.

The closest technical solution to the claimed is a catalyst for heterogeneous reactions (RF Patent 2160156, IPC7B01J 21/08, 23/38, 23/70, 37/02, 2000), in korekturos, characterized claimed in the patent features of the spectra X and AMP29Si. Such media may be obtained from a silicate glass fibre materials having different geometric shapes, including the shape of the fibers, and woven and nonwoven materials from them. This carrier proposed to be used for the preparation of heterogeneous catalysts by introducing the active component in the surface of the interlayer cavity optical fibers. The catalyst proposed to be used preferably for deep and partial oxidation of hydrocarbons, hydrogenation of hydrocarbons, alkylation of hydrocarbons, oxidation of sulfur dioxide, ammonia conversion. In the reduction reaction of nitrogen oxides with the test mixture model (0,18% NOx, 1,48% vol. CH4, 2,6 about. % O2the rest is argon) these catalysts showed high conversion at temperatures 250-750oC. However, they have not sufficiently high selectivity for nitrogen and inactive when a large excess of oxygen (>2,5 vol.% 2), and at temperatures of reaction <250With that restricts their application in the conditions of cold start of the engine.

Thus, at the present time, there is a need asrayam other than ammonia, reducing agents, having a high activity and selectivity in a wide temperature range from 50 to 600oIn contrast to the known catalysts, which begin to purify the waste gases at 200oWith enough thermostable and resistant to water, serosoderjaschei connections.

The problem solved by the present invention, is an effective catalyst for purification of exhaust gases of diesel engines from nitrogen oxides by selective reduction by hydrocarbons under oxygen excess starting to work at low temperature and to achieve a high degree of purification from the NOxin a wide temperature range of the process.

To achieve the objectives proposed a catalyst for purification of exhaust gases with excess oxygen from oxides of nitrogen, including active component carrier from a fiberglass material, in which the media use fiberglass cloth from silicate glass, leached to the content of silicon dioxide of 90.0 to 99.9 wt.% and having a specific surface area of 0.2-7.0 m2/g, as the active component, the catalyst contains at least one metal from the platinum group in the th element or several elements from the group including aluminum, iron, silicon, titanium, cerium, lanthanum, molybdenum and/or their oxides in a quantity of 0.001-0.5 wt.%, and has the following composition, wt.% (in terms of metal):

The platinum group metal - 0,001-0,3

The promoter - 0,001-0,5

Media - rest

Media for the preparation of the catalyst contains a hydroxyl group (OH) in an amount of 2 hydroxyl groups per 1 atom of silicon to 1 hydroxyl group at the 2 atom of silicon.

The media is also a woven or non-woven glass fiber materials, woven and non-woven products (fabric, jacquard, wool, felt and so on), and elementary fiber glass material have a diameter of 1-20 μm, and has a true density of 2.1-2.2 g/cm3.

Platinum in the active component has an electron state with respect to Pt2+/Pt0=0,3-0,9.

Media from fiberglass materials are obtained from a complex glass with the gross formula AmBnOh, where is stekloobraznoi cation Si4+IN3+Ge4+A - the accompanying cation. Depending on stekloobrazuyuschego cation known classes of glasses, borate, silicate, germanate. As an accompanying cations the most common is isdi flue gas with excess oxygen from oxides of nitrogen carrier of glass fiber fabric of the silicate glass, in which stekloobrazuyuschego cation is Si4+. Industrial silicate glass is usually referred to as soda-lime glass, but actually varieties of these glasses more complex, and they contain some amount of MgO, Al2ABOUT3.

Fiberglass fabric of the silicate glass is subjected to leaching, the specific surface area after leaching is 0.2-7.0 m2/g, which corresponds to the outer surface of the fibers with a diameter of 1-20 μm.

Silica glass fiber media for the preparation of the catalyst after leaching contains a 90.0 to 99.9 wt.%. silicon dioxide, the rest are the oxides of aluminum, alkaline earth metals, and has a specific surface area of 0.2-7.0 m2/,

All the catalysts prepared on the specified fiberglass fabric of the silicate glass using as an active component at least one metal of the platinum group and the above-mentioned promoters claimed in intervals of concentrations, lead to the achievement of the task.

To obtain the proposed catalyst for purification of exhaust gases with excess oxygen from oxides of nitrogen use Promyshlenny, dried at 20-250oC. Silica glass fiber material before or after leaching solution of mineral acid is treated with ammonia solution 3-7% at 20-70oWith over 10-200 minutes, washed with water, dried at from 20 to 250oWith and receive the media with the characteristics described above. The resulting carrier is impregnated with compounds active components and promoters at a temperature of 40-200oAnd pressure 1-16 antibody, followed by drying in air at 110-130oWith heat treatment in air, nitrogen, hydrogen at a temperature of 150-500oC.

Connection promoter is introduced into the carrier before application of the active ingredient or together with the application of the active component.

In the preliminary introduction of the promoter of the carrier is impregnated with a solution containing compounds of the promoter at a temperature of 40-200oC and the pressure 1-16 antibody, followed by drying in air at 110-130oC and heat treated in air or nitrogen at a temperature of 150-500oC. the resulting carrier is impregnated with compounds of the platinum group metal at a temperature of 40-200oAnd pressure 1-16 antibody, followed by drying in air at 110-130oWith heat treatment in air, nitrogen, hydrogen at a temperature of 150-500Kodama gas with excess oxygen from oxides of nitrogen, for example, diesel engines by restoring at 50-600oWith nitrogen oxides by hydrocarbons in the above-described catalyst placed in the system for purification of exhaust gas.

The proposed catalyst allows you to remove nitrogen oxides from waste gases with the oxygen content of 1.6-18 vol.%, since temperature 50oWith high selectivity, i.e., without the formation of nitrous oxide.

The cleaning process is carried out at a temperature of from 50 to 600oC.

For longer service catalyst system for the purification of exhaust gases optionally set the filter to trap large particles of soot.

The characteristic features of the processes of purification of exhaust gases of diesel engines from nitrogen oxides in the presence of the proposed catalyst are a wide temperature range of effective work (50-600oC) in contrast to the known and high selectivity (small quantities generated N2O and NO2).

This is due to the specific properties used fiberglass media in the presence of promoters.

Used vysokoglinozemistyj fiberglass media is after visadelta narrow interlayer spaces, which are hydroxyl group, and the optimum content of hydroxyl groups (OH) in an amount of 2 hydroxyl groups on one atom of silicon to 1 hydroxyl group at the 2 atoms of silicon. Leached silica-containing material contains a 90.0 to 99.9 wt.% SiO2the rest are nevydelujeme components, including aluminum oxide and alkaline-earth components that are remote from the surface areas and do not affect the properties of the surface layers of the glass fiber media. With the introduction of such a carrier of the active components (metals of group VIII) they are localized in the interlayer cavities near the outer surface of the fiber, while in the immediate coordination environment of the metal may contain silicon and oxygen. Proposed in the present invention the introduction of additional promoters at optimal concentrations and conditions of synthesis changes the properties of the surface layers of media (chemical composition, structure and acid-basic properties of the surface). This affects the state introduced into the carrier of the active component. For example, the availability of suitable promoters increases the dispersion of the applied active the th. By x-ray photoelectron spectroscopy measurements were performed on electron spectrometer VG ES-CALAB HP) in Pt-containing catalysts revealed the presence of two States of platinum in the form of metal (ESt(4f7/2)= 71.2 eV) and charged platinum, characterized by higher values of bond energy. For catalysts promoted according to the present invention and having a high activity and selectivity, is characterized by a relatively high content of charged metal than metal with zero valency ratio (M2+/M0=0,3-0,9), while for ineffective catalysts the ratio of M2+/M0<0,3.2the number of 90.0 to 99.9 wt.%, declare promoters can significantly increase the acidity of the surface. In combination with the above-mentioned specific conditions of the active component that determines a characteristic of the claimed catalyst of high activity and selectivity in a wide temperature range.

In addition, what is happening with the introduction of the promoters of the coordination sphere of the active metal and the increase in energy due to the notes to maintaining high dispersion and activity of the applied active phases, as well as their resistance to the action of toxic substances, i.e., increases the resistance of the catalyst to high temperature and poisoning.

When the content of the promoter less than 0.001 wt.% reduced low-temperature (<200(C) the activity recovery of oxides of nitrogen, and when the content of the promoter of above 0.5 wt.% reduced selectivity (increases the amount of N2O).

The amount of platinum group metal is 0.001 to 0.3 wt. %. With the introduction of the active component more than 0.3 wt.% the selectivity in the reaction of removal of nitrogen oxides is reduced due to the increase in the concentration of nitrous oxide and increase the speed of deep oxidation of hydrocarbons.

The proposed catalyst has high activity at very low concentration of active component (0,001% by weight) maintain high selectivity of the reduction of nitrogen oxides to molecular nitrogen, which distinguishes it from known catalysts, which use much larger quantities of noble metals (up to 1 wt.%)

The assigned task is achieved by the use of the promoters from the group of aluminum, iron, silicon, titanium, cerium, lanthanum, molybdenum, or their oxides, taken in about what I promoter and the active component is selected in a certain interval, when applied for the active component (metal of group VIII) can be achieved with high dispersion and electron state, corresponding to the value2+/M0=0,3-0,9. This leads to the fact that the removal of nitrogen oxides begins at 50oIn contrast to the known catalysts, which begin to restore nitrogen oxides at temperatures above 200oC. in Addition, in contrast to the known catalysts (Pt and Pd on Al2ABOUT3and SiO2) during the oxidation of nitrogen oxides by hydrocarbons in oxygen excess N2O is not formed or is formed in very small amounts, i.e., and the catalyst has a high selectivity towards the formation of N2.

The proposed catalyst was prepared as follows.

Industrial silicate glass, made in the form of fibers, woven and non-woven products, leached in the acid solution. Leaching is carried out in such a way as to receive the media content of silicon oxide from a 90.0 to 99.9 wt.% (preferably above 98 wt.%), the true density of 2.1-2.2 g/cm3and a specific surface area of 0.2-7.0 m2/, Before or after the leaching medium further treated with a solution of ammonia 3-7 Doliny be observed optimal conditions impregnation compounds active components and promoters. Such conditions are: impregnation at an elevated temperature of from 40 to 200oC and a pressure of from 1 to 16 ATA, and the promoter can be introduced into the catalyst in two ways.

Under the first mode fiber media impregnated with at elevated temperatures from 40 to 200oAnd pressure 1-16 at connections promoter with subsequent washing and heat treatment of the carrier and further impregnated with compounds of the active component also at elevated temperature and pressure. Elevated temperature and pressure conducive to the establishment and consolidation of the promoter and active components not only on the outer surface of the fibers, but also in the interlayer cavities, and in the scope of fiberglass silica fiber, because in these conditions increases the diffusion of active components and intensified ion exchange of protons of hydroxyl groups of the carrier on the cations of the compounds of the promoters and active components.

In the second method, the promoter is injected simultaneously with the active component, while the connection of the promoter is added in an impregnating solution of compounds of the active component.

After contact of the carrier with an impregnating solution of compounds active components is in the air, nitrogen or hydrogen at a temperature of 150-500oC.

The use of the proposed method of preparation of the catalyst ensures its high activity in a wide temperature range, high selectivity (absence or low content of N2O), resistance to otravlyayuscikh the effects of sulphur compounds and resistance to sintering, sintering of the catalytic components or their detachment from the carrier.

Test samples of the catalysts were carried out in model reduction reaction of NO with propane in a laboratory setup, which included a flow-through tubular reactor made of quartz glass, is placed in an electric furnace, the unit dosage gases, the mixing unit flow and analysis system gas composition. The oven temperature was controlled with a slider Miniterm 005". The concentration of NO and NO2in the source and destination of the mixture was determined by chemiluminescent method for the Quintox analyzer To 9600. The content of N2O was determined by the method of X using a calibrated gas cell.

For tests used a gas mixture of two compounds. A mixture of A-250ppm NO + 250ppm3H8+3,5% vol. ABOUT2the rest is helium. To assess the stability of UB> +50ppm SO2the rest is helium. It was found that for all the claimed catalysts introduction in the gas mixture SO2does not reduce activity. Listed in the table and in Fig.1 data on the catalytic activity refer to the test mixture containing 50 ppm of SO2.

In separate experiments, the content of O2in the original mixture was increased to 18% vol. (example 11) and was reduced to 1.8% (example 10).

In separate experiments, the reaction mixture was added to 5% vol. H2(Example 12).

The addition of catalyst was 0.4 g or 1 cm3, the volumetric rate of the gas mixture 25000 h-1.

The degree of conversion of nitrogen oxides (X,%) was calculated by the formula

X=(C0no- CNO)/C0no100,

where0no- the initial concentration of NO;

Cnothe concentration of NO in the converted gas.

Selectivity for nitrogen (SN2,%) was calculated by the formula

SN2=CN2/(CN2+2CNO2+ CN2O) 100

CN2the concentration of N2in the converted gas;

CNO2the concentration of NO2in the converted gas;

CN2Othe concentration of N2O in the converted gas.

3 the rest is made of glass fibers with a diameter of 7 μm, treated in a solution of 3% ammonia at 20oC for 60 minutes, then washed with deionized water until neutral, dried in air at 110oC. the Obtained sample treated with 5% solution model HC1 at 90oC for 90 minutes, washed with deionized water until neutral, dried in air at 110oC. the Obtained sample containing a 99.0 wt.% SiO2that is impregnated with a Sol of aluminum silicate containing about 0.15 wt.% Si and 0.1 wt.%. Al at 50oAnd atmospheric pressure (P=AC) for 30 minutes, then washed 10-fold excess of deionized water, dried at 110oC for 12 hours and calcined at 300oC in air for 4 hours. The sample obtained is impregnated with a solution of emmakate platinum with a concentration of 0.2 wt.% Pt at 200oWith the pressure of 16 at 12 hours, washed with 5-fold excess of deionized water, dried at 110oC for 12 hours, and calcined 2 hours at 300oC in air for 2 hours at 300oWith the hydrogen.

Sample experience in the reduction reaction of NO with propane in accordance with the above method on the gas mixture In - 250ppm NO + RT3H8+ 3,5% vol. ABOUT2+ 8 (curve 2) when changing the reaction temperature from 50 to 660oC. In Fig.4 for comparison, the results of the test in similar conditions catalyst comparison, Pt/Al2ABOUT3containing 0,64% Pt. It is evident from Fig.1 shows that proposed in the present invention the catalyst of example 1 is already at the 50oWith shows NO conversion of about 30% and when the temperature is raised to 330 With the conversion increases to 63%. With further increase in temperature there is a decrease in the conversion rate, but even at 650oSince it remains at the level of 25% in excess of the conversion on the known catalysts. In the whole temperature interval selectivity for nitrogen is at least 90%. Test mixture And gives similar results on activity and selectivity.

As can be seen from Fig.4, in a similar test conditions on the reference sample (of 0.64 wt.% Pt/Al2ABOUT3) significant conversion of NO is observed at a temperature of 300oWith 400-450oWith maximum conversion 20-22% at 550oWith the conversion of NO is reduced almost to zero level with a sharp increase in the conversion of propane. The selectivity for N2in the whole interval is about 50%.

Example 2

Industrial sodium silicate fiberglass 10 μm, process 7% solution of HNO3if 70oC for 60 minutes, washed with deionized water until neutral, dried in air at 110oC. the Obtained sample is treated in a solution of 7% ammonia at 50oC for 150 minutes, then washed with deionized water until neutral, dried in air at 200oC. the Obtained sample containing 98 wt.% SiO2that is impregnated with a Sol of aluminum silicate containing 0.4 wt.% Al and 0.1 wt.% Si 100oC and a pressure of 1.5 ATA for 30 minutes, then washed 10-fold excess of deionized water, dried at 110oC for 12 hours and calcined at 300oC in air for 4 hours. The sample obtained is impregnated with a solution of emmakate platinum concentration 0.5 wt.% Pt at 160oC, a pressure of 7 bar for 12 hours, washed with 5-fold excess of deionized water, dried at 110oC for 12 hours, and calcined 2 hours at 200oC in air for 2 hours at 200oWith the hydrogen.

Sample experience in the reduction reaction of NO with propane in accordance with the above method on a mixture of C. the Results are shown in table 2 and Fig. 3.

Example 3. Similar to example 2, characterized in that the promoter enter one the of conduct impregnation leached steklotarnogo carrier with a solution of Al2(SO4)3with a concentration of 2 wt.% A1 at a temperature of 20oC for 10 minutes. The test results are shown in table 2 and Fig.3.

Example 5. Similar to example 1, characterized in that the promotion carried out by impregnation leached steklotarnogo media obtained from the original fiberglass fabric following composition: 80% SiO2, 20% Na2O, the mixture of the solutions of CE(NO3)3(0.2 wt. % Mo)+La(NO3)3(0.2 wt.% La)+ Fe(NO3)3(0.02 wt.% Fe) at a temperature of 50oC for 20 minutes.

Example 6. Similar to example 1. Differs in that promotion carried out by impregnation leached steklotarnogo media solution paramolybdate ammonium (NH4)6Mo7O24with a concentration of 1.0 wt.% Mo.

Examples 7-10

The catalysts are prepared analogously to example 1, however, they are different active ingredients, promoters and their quantity. Data on the composition of the catalysts are shown in table 1, the data about the properties of the catalyst are shown in table 2.

Example 11. Similar to example 1, but in the testing of catalyst used, the reaction mixture composition 250ppm NO + RT3H8+18% vol. O2+ RT SO2, the rest of MES composition 250ppm NO + RM C3H8+ 3,5% vol. O2+ RM SO2+ 5% vol. H2O, the rest is helium.

Example 13 (prototype)

The high activity of the new catalyst, thermal stability, the abrasion resistance and other properties confirm the effectiveness and appropriateness of a new catalyst for purification of exhaust gases from nitrogen oxides by selective catalytic reduction with hydrocarbons.

1. The catalyst for purification of exhaust gases with excess oxygen from oxides of nitrogen, including the active ingredient, the carrier of fiberglass material, characterized in that as the carrier is used fiberglass fabric of the silicate glass leached until the content of silicon dioxide of 90.0 to 99.9 wt.% and having a specific surface area of 0.2-7.0 m2/g, as the active component, the catalyst contains at least one metal from the platinum group in the amount of 0.001 to 0.3 wt.% and further comprises a promoter, representing a combination of at least one element or more elements from the group comprising aluminum, iron, silicon, titanium, cerium, lanthanum, molybdenum and/or their oxides in a quantity of 0.001-0.5 wt.%, and has the following composition, wt.%, in lane 2. The catalyst p. 1, characterized in that the carrier for the preparation of the catalyst contains a hydroxyl group (OH) in an amount of 2 hydroxyl groups per 1 atom of silicon to 1 hydroxyl group at the 2 atom of silicon.

3. The catalyst p. 1, characterized in that the carrier is a woven or non-woven glass fiber materials, and elementary fiber glass material have a diameter of 1-20 μm.

4. The catalyst p. 1, characterized in that the carrier has a true density of 2.1-2.2 g/cm3.

5. The catalyst p. 1, characterized in that the platinum in the active component has an electron state with respect to Rt2+/Pto= 0,3-0,9.

6. A method of producing a catalyst for purification of exhaust gases with excess oxygen from nitrogen oxides, comprising a carrier impregnated from fiberglass material compounds active ingredients at a temperature of 40-200oAnd pressure 1-16 al., drying, heat treatment, characterized in that as the carrier is used fiberglass fabric of the silicate glass leached until the content of silicon dioxide of 90.0 to 99.9 wt.% and having a specific surface area of 0.2-7.0 m2/g, after carrying out the surface of 0.2-7.0 m2/g is impregnated with compounds of the active component and the promoter, the promoter is at least one compound or mixture of compounds from the group of elements, including: aluminum, iron, silicon, titanium, cerium, lanthanum, molybdenum, and impregnation compounds promoter carried out before application of the active ingredient or together with the application of the active component, and then conducting heat treatment of the catalyst at a temperature of 150-500oWith and obtain a catalyst of the following composition, wt.%, in terms of metal:

The platinum group metal - 0,001-0,3

The promoter - 0,001-0,5

Media - Rest

7. The method according to p. 7, characterized in that the heat treatment is conducted in air or in a stream of nitrogen, or in a stream of hydrogen.

8. The method according to p. 7, wherein after washing the carrier with water are treated with a solution of ammonia with a concentration of 3-7 wt.% when 20-70oC.

9. The method according to p. 7, characterized in that the metal in the active component has an electron state with regard to M2+/Mo= 0,3-0,9.

10. Method of cleaning exhaust gases with excess oxygen from nitrogen oxides by reduction of nitrogen oxides, hydrocarbons on the catalyst, vkluchaya gas, at elevated temperature, characterized in that the use of a catalyst containing as a carrier for glass fiber fabric of the silicate glass leached until the content of silicon dioxide of 90.0 to 99.9 wt. % and having a specific surface area of 0.2-7.0 m2/g, as the active component, the catalyst contains at least one metal from the platinum group in the amount of 0.001 to 0.3 wt.% and the catalyst further comprises a promoter, representing a combination of at least one element or elements from the group comprising aluminum, iron, silicon, titanium, cerium, lanthanum, molybdenum and/or their oxides in a quantity of 0.001-0.5 wt.%, and has the following composition, wt.%, in terms of metal:

The platinum group metal - 0,001-0,3

The promoter - 0,001-0,5

Media - Rest

and the reduction of nitrogen oxides is carried out at a temperature of 50-600oC.

11. The cleaning method according to p. 10, characterized in that the system for cleaning of exhaust gases optionally set the filter to control particles of soot.

12. The cleaning method according to p. 10, characterized in that the exhaust gases are oxygen concentration of 1.6-18 vol.%.

 

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The invention relates to the production of palladium catalysts for selective hydrogenation of organic compounds

The invention relates to a method for heterogeneous bimetallic palladium-gold catalyst to obtain a vinyl acetate from ethylene, acetic acid and oxygen

The invention relates to catalysts for (co)polymerization of ethylene containing chromium trioxide deposited on a solid inorganic oxide carrier of nature, i.e

The invention relates to a method for hydrogenation of aromatic ketones, which are intermediate compounds used in the production of dyes, varnishes, resins

The invention relates to the chemical industry, and in particular to methods of preparation of catalysts for the process of ethylene oxide gas-phase oxidation of ethylene with oxygen

The invention relates to the production of catalysts, in particular latinoreview catalyst for reforming of gasoline fractions

The invention relates to the catalytic substance and the method of its production

The invention relates to the production of catalysts in various chemical processes, in particular for fine purification of hydrocarbon systems from acetylenic and diene compounds present in a mixture with monoolefinic

The invention relates to the production of catalysts for heterogeneous processes, which are used in carrying out various chemical reactions, in particular catalysts for oxidation of SO2and SO3in the manufacture of sulfuric acid or purifying gases

The invention relates to the field of catalysts, in particular for the hydrogenation of vegetable oils and fats, and can be used in the food, perfume, petrochemical and refining industries

The invention relates to catalysts for hydrogenations of aromatic nitro compounds and can be used in the manufacture of dyes, upon receipt of the primary amines used in the manufacture of caprolactam, isocyanates, in the syntheses of means for plant protection

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

The invention relates to the field of technical chemistry, namely, catalysts (catalytic elements) for deep oxidation of carbon monoxide, hydrocarbons and other substances by burning fuel, the oxidation of harmful pollutants in the exhaust gases of industrial plants

The invention relates to a yarn comprising at least one filiform element, connections, threads, especially in the form of fabrics, knitted fabrics or felt, the use of these compounds as a catalyst, the catalyst and the capture device for the purpose of recovery of precious metals

The invention relates to materials for the implementation of catalytic processes and can be used in chemical, petrochemical, light industry, in particular for the treatment of wastewater and gas emissions from sulphides

The invention relates to the field of heterogeneous catalysis, and in particular to a catalyst and method for preparing a catalyst for selective hydrogenation of diene and acetylene hydrocarbons into olefins
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