CN111939988A - Method for improving catalytic performance of nano diesel engine tail gas in SCR temperature zone - Google Patents
Method for improving catalytic performance of nano diesel engine tail gas in SCR temperature zone Download PDFInfo
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- 230000003197 catalytic effect Effects 0.000 title claims abstract description 27
- 238000000034 method Methods 0.000 title claims abstract description 17
- 239000003054 catalyst Substances 0.000 claims abstract description 41
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- 238000000576 coating method Methods 0.000 claims description 62
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- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 40
- 229910052697 platinum Inorganic materials 0.000 claims description 19
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 16
- 229910052802 copper Inorganic materials 0.000 claims description 16
- 239000010949 copper Substances 0.000 claims description 16
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- 239000002808 molecular sieve Substances 0.000 claims description 9
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- 239000000969 carrier Substances 0.000 claims description 3
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- 229910052751 metal Inorganic materials 0.000 claims description 3
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- 229910052863 mullite Inorganic materials 0.000 claims description 3
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- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 abstract description 69
- 239000007789 gas Substances 0.000 abstract description 18
- 238000005516 engineering process Methods 0.000 abstract description 15
- 230000000694 effects Effects 0.000 abstract description 9
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- 238000006243 chemical reaction Methods 0.000 description 7
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- 238000003466 welding Methods 0.000 description 4
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- MAKDTFFYCIMFQP-UHFFFAOYSA-N titanium tungsten Chemical compound [Ti].[W] MAKDTFFYCIMFQP-UHFFFAOYSA-N 0.000 description 3
- WKXHZKXPFJNBIY-UHFFFAOYSA-N titanium tungsten vanadium Chemical compound [Ti][W][V] WKXHZKXPFJNBIY-UHFFFAOYSA-N 0.000 description 3
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 2
- GQPLMRYTRLFLPF-UHFFFAOYSA-N Nitrous Oxide Chemical compound [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 2
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 238000000498 ball milling Methods 0.000 description 2
- 239000004202 carbamide Substances 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- GNTDGMZSJNCJKK-UHFFFAOYSA-N divanadium pentaoxide Chemical compound O=[V](=O)O[V](=O)=O GNTDGMZSJNCJKK-UHFFFAOYSA-N 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
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- 230000008929 regeneration Effects 0.000 description 2
- 238000011069 regeneration method Methods 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 1
- 239000005751 Copper oxide Substances 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- XHCLAFWTIXFWPH-UHFFFAOYSA-N [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] XHCLAFWTIXFWPH-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000003916 acid precipitation Methods 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000003915 air pollution Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000012876 carrier material Substances 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 229910000431 copper oxide Inorganic materials 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
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- 229910052760 oxygen Inorganic materials 0.000 description 1
- NWAHZABTSDUXMJ-UHFFFAOYSA-N platinum(2+);dinitrate Chemical compound [Pt+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O NWAHZABTSDUXMJ-UHFFFAOYSA-N 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910001935 vanadium oxide Inorganic materials 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/024—Multiple impregnation or coating
- B01J37/0244—Coatings comprising several layers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
- B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
- B01D53/9404—Removing only nitrogen compounds
- B01D53/9409—Nitrogen oxides
- B01D53/9413—Processes characterised by a specific catalyst
- B01D53/9418—Processes characterised by a specific catalyst for removing nitrogen oxides by selective catalytic reduction [SCR] using a reducing agent in a lean exhaust gas
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J23/24—Chromium, molybdenum or tungsten
- B01J23/30—Tungsten
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- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/56—Platinum group metals
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- B01J29/00—Catalysts comprising molecular sieves
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2258/00—Sources of waste gases
- B01D2258/01—Engine exhaust gases
- B01D2258/012—Diesel engines and lean burn gasoline engines
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- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
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Abstract
The invention discloses a method for improving the catalytic performance of nano diesel engine tail gas in an SCR temperature zone. The invention uses the combination of the prior SCR formula technology, the nano noble metal catalysis technology and the system to improve the activity of the SCR catalyst, expand the effective temperature zone of the catalyst, achieve the aim of more effectively controlling the nitrogen oxide in the tail gas of the diesel engine, and simultaneously ensure the simplicity, the practicability and the cost control of the system.
Description
The technical field is as follows:
the invention belongs to the field of diesel engine tail gas control post-treatment catalysts, and particularly relates to a method for improving the catalytic performance of nano diesel engine tail gas in an SCR temperature zone.
Background art:
nitrogen oxides in air pollution are mainly nitrogen monoxide (NO) and nitrogen dioxide (NO2), which are collectively called nitrogen oxides (plus N2O, which is collectively called NOx), and their main sources are mobile sources (vehicles, about 50%) and stationary sources (thermal power plants, etc., about 45% or more). Nitrogen oxides (NOx) are one of the main harmful substances in the exhaust gas of internal combustion engines (mainly piston gasoline engines and diesel engines) and are also the main causes of acid rain and photochemical smog formation. The technology for controlling the nitrogen oxides of the gasoline engine is mature, and the requirements of emission regulations can be well met only by installing a three-way catalyst in a tail gas system under the condition of theoretical air-fuel ratio combustion. The diesel engine is complicated because oxygen-rich combustion and the three-way catalytic technology is basically ineffective in controlling the nitrogen oxides, so that a new technology must be developed. Before the national 5 emission standard, the emission of nitrogen oxides can be effectively reduced by adopting in-cylinder purification measures such as delayed oil injection, waste gas recirculation and the like. With the implementation of national 5 and 6 standards, the internal purification technology cannot meet the requirements of regulations, and an oxidation catalyst (DOC), a Diesel Particulate Filter (DPF) and a selective catalytic reduction technology (SCR technology) become essential exhaust aftertreatment systems of diesel engines, wherein the SCR technology almost becomes the only effective nitrogen oxide control technology.
The SCR technology relies on the fact that urea is injected into the exhaust pipe under the action of a catalyst and atomized to form ammonia (NH3) as a reducing agent, which, in combination with the catalyst, can very effectively convert nitrogen oxides in the exhaust gas of a diesel engine into nitrogen (N2) and water (H2O). Currently, the most commonly used SCR catalysts are vanadium-based (vanadium tungsten titanium) SCR, manganese-based SCR, copper-based molecular sieve SCR, iron-based molecular sieve SCR, platinum-based SCR, and the like. The SCR catalysts have their own characteristics, in which the temperature characteristics (temperature window) are important and the exhaust temperatures of different engines vary greatly, so that it is important to select different catalysts according to the temperature window of the diesel engine. CN108697980A uses two SCR coatings A and B respectively coated on the inlet side and the outlet side of the microporous wall of the DPF of the wall-flow type particulate trap to form a nitrogen oxide treatment system integrating the DPF and the SCR. CN104190413A applied different combinations of platinum (Pt) and palladium (Pd) to make DOC generate higher NO2, which is beneficial to not only DPF regeneration but also SCR reduction of nitrogen oxides. The zoned-stratified SCR technique is described in CN105026038A, in order to achieve a balance and high temperature thermal stability (tested to 450 ℃) that enhances or suppresses the production of N2 and N2O. The staged coating of different combinations of platinum and palladium used in CN108579801A is actually a staged DOC formulation technique to promote oxidation of NO to NO2 at lower temperatures, to provide the required NO2 for downstream DPF and SCR catalyst reactions, to promote DPF regeneration and NOx reduction conversion. In order to meet the requirement of the national 6 standard and improve the urea injection uniformity and the disassembly convenience, the CN208364220U adopts a cylinder-connected structure, a bipolar SCR carrier is arranged in a first cylinder so as to convert nitrogen oxide NOx into N2 and water, and a DOC and a DPF are arranged in a second cylinder.
At present, the selective reduction catalyst SCR used for controlling nitrogen oxides of diesel machinery and diesel vehicles is mainly as follows, platinum-based SCR is a catalyst using noble metal platinum (Pt) as a main catalytic element, and is suitable for exhaust temperature of 150-350 ℃, and the noble metal platinum is adopted to ensure that the activity of the catalyst is strongest, the reduction temperature in all SCR formulas is the lowest, but the price is the highest. Vanadium oxide is often combined with tungsten titanium powder to form a vanadium-based catalyst, which is a relatively low-cost SCR catalyst and is generally suitable for use at 300-450 ℃. The copper-based and iron-based molecular sieves SCR are the first choice of the current 6-emission standard in China, are suitable for higher exhaust temperature, are generally suitable for 350-600 ℃, but have unsatisfactory effects at low temperature.
As described above, different SCR technologies are applicable to different exhaust temperature ranges, and most of the national 5 standards use vanadium-based SCR, and most of the national 6 standards use copper-based or iron-based molecular sieve SCR. The disadvantage is that none of them is able to cover the temperature range of the diesel engine ideally, resulting in less than ideal effects for the control of nitrogen oxides in the exhaust gases.
The invention content is as follows:
the invention aims to provide a method for improving the catalytic performance of the tail gas of a nano diesel engine in an SCR temperature zone, which improves the activity of an SCR catalyst and expands the effective temperature zone of the catalyst by applying the combination of the existing SCR formula technology, the nano noble metal catalysis technology and a system, achieves the aim of more effectively controlling nitrogen oxides in the tail gas of the diesel engine, and simultaneously ensures the simplicity, the practicability and the cost control of the system.
In order to solve the problems, the technical scheme of the invention is as follows:
a method for improving the catalytic performance of the tail gas of a nano diesel engine in an SCR temperature zone is characterized in that an SCR catalyst coating is coated on an SCR catalytic carrier, and the SCR catalyst coating comprises at least two of a high-temperature SCR coating, a medium-temperature SCR coating and a low-temperature SCR coating.
In a further improvement, the high-temperature SCR coating is a copper-based or iron-based molecular sieve SCR coating; the medium-temperature SCR coating is a vanadium-based SCR coating; the low-temperature SCR coating is a platinum-based SCR coating.
In a further improvement, the platinum-based SCR coating is a nano precious metal platinum oxide colloid solution coating.
In a further improvement, the high-temperature SCR coating, the medium-temperature SCR coating and the low-temperature SCR coating are coated on the carrier along the upstream and downstream sections.
In a further improvement, the pH value of the SCR catalyst coating is 2.8-3.5, and the mass percentage of solid matters in slurry of the SCR catalyst coating is 28-40%.
In a further improvement, the number of the SCR catalytic carriers is one or two.
In a further improvement, the surface of the SCR catalytic carrier is integrally coated with an SCR catalyst coating; the SCR catalytic carrier is ceramic, cordierite, silicon carbide, mullite or metal.
The invention has the advantages that:
the invention reduces the welding steps, ensures the welding quality, saves the manufacturing cost and improves the yield and the quality of products by improving the structure of the welding cutter and the welding method thereof.
Description of the drawings:
FIG. 1 is a schematic view of a single carrier and single coating;
FIG. 2 is a schematic view of a single carrier segment coating architecture;
FIG. 3 is a schematic diagram of a dual carrier system;
FIG. 4 is a graph showing the TPR test results of a platinum-based SCR sample;
FIG. 5 is a graph of NO conversion tests for vanadium-based SCR and copper-based SCR;
FIG. 6 NO conversion test of vanadium-based and copper-based segment-combined SCR.
The specific implementation mode is as follows:
the invention adopts two technical approaches to achieve the purposes of controlling the cost and widening the working temperature window of the catalyst. Firstly, before the platinum-based SCR is manufactured, a nano noble metal platinum oxide colloid solution is adopted to replace the traditional industrialized platinum salt solution at present, the manufacturing technology of the nano noble metal platinum oxide colloid solution is described in CN105833862B, and the aim is that the same amount of noble metal nano platinum has higher catalytic activity or less noble metal nano platinum has the same catalytic activity, so that the effect of reducing the cost is achieved; secondly, coating the platinum-based, vanadium-based and copper-based SCR catalysts on the front and rear half sections of the ceramic carrier in sections according to a combination method; two supports can also be used, with three or four SCR coatings being applied in upstream and downstream stages. The carrier material may be common ceramics (cordierite, silicon carbide or mullite) or metal. The pH value (pH value) of the catalyst coating slurry is adjusted to be between 2.8 and 3.5, and the solid percentage is adjusted to be between 28 and 40 percent.
FIG. 1 shows a single support, single coating system, with the entire support coated with the same formulation of SCR catalyst.
FIG. 2 shows a single support dual coating system with a platinum-based SCR coating 1 on the upstream section of the catalyst support and a vanadium-based SCR coating 2 on the downstream section of the catalyst support; or the upstream section adopts a vanadium-based SCR coating, and the downstream section adopts a copper-based SCR coating.
As shown in fig. 3, a dual-carrier system is provided, one catalyst carrier uses a platinum-based SCR coating 1, the other catalyst carrier uses a vanadium-based SCR coating 2 at the upstream section and uses a copper-based SCR coating 3 at the downstream section. The SCR catalysts in the three different temperature zones can be integrally arranged in a tail gas system of the diesel engine. It is also possible to place 2, 3 upstream of the gas stream and a support coated with a platinum-based SCR coating downstream.
Example 1
This example was used to prepare a sample of the coating, to examine the activity of nano-platinum oxide as the main catalytic element, and to compare it with the coating prepared from the conventional industrial platinum salt. Cerium-zirconium solid solution and modified alumina produced by using boule crystal are used as main coating materials, wherein the proportion of gamma modified alumina, cerium-zirconium solid solution 1055 and cerium-zirconium solid solution 1062 for preparing samples is 1: 0.5: 0.5. the nano platinum oxide gel solution is added into the sample 1, the industrialized platinum nitrate solution is added into the sample 2, and the platinum content (weight) in the samples is 2.50 percent. The pH value of the sample slurry is about 3, the sample slurry is fully stirred and then is dried (100 ℃) and roasted (650 ℃) to form uniform powder which is used as a test sample, and finally, a Temperature Programmed Reduction (TPR) test is carried out.
Example 2
Three catalyst carriers were used, the material being a cylindrical cordierite ceramic carrier, with a pore density of 300 mesh (pores per square inch), a diameter of 25.0mm and a length of 40.0 mm. Examples two formulations were used to make the test swatches. The formula A adopts vanadium-based SCR with moderate temperature zone, applies tungsten titanium powder DT52 for Shanghai canal SCR, and adds vanadium pentoxide (V) 5% of the total weight of DT522O5) Adding the tungsten-titanium powder into an acidic aqueous solution, (regulating the pH value to 3.0-3.5 by using deionized water and 2% concentrated nitric acid or acetic acid), and performing ball milling for 1 hour to form coating slurry with the pH value of 3.0-3.5; the formula B adopts Cu-TZB223L copper-based molecular sieve material of Shanghai canal, the content of copper oxide is about 4.0%, acid solution is added (deionized water and 2% concentrated nitric acid or acetic acid are used for adjusting the pH value to 3.0-3.5), and coating slurry with the pH value of 3.0-3.5 is formed by ball milling for 1 hour. The mass percentage of solid matter in both slurries was 35%.
The first sample was coated with a single catalyst support using a vanadium tungsten titanium SCR formulation as shown in figure 1.
The second sample was coated as shown in fig. 1 using a copper-based molecular sieve SCR formulation to form a single catalyst support.
In a third sample, as shown in fig. 2, the upstream part (50% of the length of the carrier) of the inlet end is coated with the same vanadium-tungsten-titanium SCR coating as the first piece, and the downstream part (50% of the length of the carrier) of the outlet end is coated with the same copper-based molecular sieve SCR coating as the second piece, so as to form a segmented dual-formulation system.
The three samples were loaded with carrier coatings at about 185 grams per liter.
Example 1 results
Fig. 4 shows the results of Temperature Programmed Reduction (TPR) tests on samples of catalyst coatings made according to example 1. The results show that greater catalytic activity can be achieved with the same noble metal content (same cost), while less noble metal content can be used (lower cost) to achieve the same activity.
Example 2 results
Fig. 5 is a simulated gas test result of a first piece of a vanadium-based SCR and a second piece of a copper-based SCR carrier sample of example 2. The simulated mixed gas map is prepared according to the components of the tail gas of the diesel engine and contains CO and CO2、NO、C3H6、O2Water vapor (H)2O) and ammonia NH3The Space Velocity (Space Velocity) in the test was 60000. Therefore, the NO conversion rate of the vanadium-based SCR at 180 ℃ reaches 80%, but the NO conversion rate is sharply reduced after 400 ℃; and the conversion rate of the copper-based SCR is over 80 percent between 230 ℃ and 500 ℃.
FIG. 6 is a simulated gas test result for a third SCR carrier of example 2. The carrier is coated with vanadium-based and copper-based SCR coatings in sections. Compared with the figure 5, the effect of expanding the temperature window is achieved by combining the two formulas in a segmented manner.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (7)
1. A method for improving the catalytic performance of nano diesel engine tail gas in an SCR temperature zone is characterized in that an SCR catalytic carrier is coated with an SCR catalyst coating, and the SCR catalyst coating comprises at least two of a high-temperature SCR coating, a medium-temperature SCR coating and a low-temperature SCR coating.
2. The method for improving the catalytic performance of the tail gas of the nano diesel engine at the SCR temperature zone according to claim 1, wherein the high-temperature SCR coating is a copper-based or iron-based molecular sieve SCR coating; the medium-temperature SCR coating is a vanadium-based SCR coating; the low-temperature SCR coating is a platinum-based SCR coating.
3. The method for improving the catalytic performance of nano diesel engine exhaust in an SCR temperature zone of claim 1, wherein the platinum-based SCR coating is a nano noble metal platinum oxide gel solution coating.
4. The method for improving the catalytic performance of nano diesel exhaust of an SCR temperature zone according to claim 1, wherein the high temperature SCR coating, the medium temperature SCR coating and the low temperature SCR coating are coated on the carrier in a staged manner along the upstream and downstream.
5. The method for improving the catalytic performance of the tail gas of the nano diesel engine in the SCR temperature zone according to claim 1, wherein the pH value of the SCR catalyst coating is 2.8-3.5, and the mass percentage of solid matters in the slurry of the SCR catalyst coating is 28-40%.
6. The method for improving the catalytic performance of the nano diesel engine exhaust in the SCR temperature zone according to claim 1, wherein the number of the SCR catalytic carriers is one or two.
7. The method for improving the catalytic performance of the nano diesel engine tail gas in the SCR temperature zone according to claim 1, wherein the surface of the SCR catalytic carrier is coated with an SCR catalyst coating; the SCR catalytic carrier is ceramic, cordierite, silicon carbide, mullite or metal.
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Citations (3)
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|---|---|---|---|---|
| CN106944130A (en) * | 2017-03-09 | 2017-07-14 | 无锡威孚环保催化剂有限公司 | A kind of SCR AOC combination catalysts of purification of diesel tail gas and preparation method thereof |
| CN208330496U (en) * | 2018-06-19 | 2019-01-04 | 中国石油天然气集团有限公司 | A kind of Test Rig SCR denitration equipment |
| CN111465754A (en) * | 2017-12-15 | 2020-07-28 | 优美科股份公司及两合公司 | Combination of zeolite-based SCR catalyst and manganese-based SCR catalyst in bypass |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106944130A (en) * | 2017-03-09 | 2017-07-14 | 无锡威孚环保催化剂有限公司 | A kind of SCR AOC combination catalysts of purification of diesel tail gas and preparation method thereof |
| CN111465754A (en) * | 2017-12-15 | 2020-07-28 | 优美科股份公司及两合公司 | Combination of zeolite-based SCR catalyst and manganese-based SCR catalyst in bypass |
| CN208330496U (en) * | 2018-06-19 | 2019-01-04 | 中国石油天然气集团有限公司 | A kind of Test Rig SCR denitration equipment |
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