Ferrous modified molecular sieve type diesel engine selective catalytic reduction catalyst

A molecular sieve and catalyst technology, which is applied to the catalyst for purifying nitrogen oxides in the exhaust gas of internal combustion engines and the field of preparation thereof, can solve the problems of low chemical activity and unfavorable catalysis, so as to reduce environmental hazards, promote oxygen storage performance, and improve low-temperature SCR. The effect of reaction catalytic activity

Active Publication Date: 2017-05-10
TIANJIN UNIV
View PDF6 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the metal elements in the existing Cu and Fe modified molecular sieve SCR catalysts are in the most stable high-valence state, and their chemical activity is low, which is not conducive to the catalytic effect of the corresponding catalyst in low temperature reactions.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Ferrous modified molecular sieve type diesel engine selective catalytic reduction catalyst
  • Ferrous modified molecular sieve type diesel engine selective catalytic reduction catalyst
  • Ferrous modified molecular sieve type diesel engine selective catalytic reduction catalyst

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0037] (3) Preparation of coating slurry

[0038] The prepared ferrous-La bimetallic modified ZSM-5 molecular sieve main catalyst and Ce(NO 3 ) 3 ·6H 2 O, Zr(NO 3 ) 4 ·5H 2 O, pure γ-Al 2 o 3 Powder, pure TiO 2 Powder, silica sol, polyethylene glycol, and nitric acid are added to deionized water whose mass is equivalent to 10 to 15 times the total mass of the catalytic coating to be prepared, and fully stirred to form a uniform slurry. Adjust the pH value of the homogeneous slurry to 3-4 with 1mol / L sodium hydroxide solution or glacial acetic acid. The uniform slurry is ground on a wet grinder until the D50 particle size is in the range of 1.0-1.2 microns, and then the ground uniform slurry is stirred at 60-80° C. for 16-24 hours to obtain the coating slurry.

[0039] (4) Coating of coating slurry

[0040] Design the mass of the 400-mesh cordierite honeycomb ceramic carrier to be coated with the catalytic coating; weigh the cylindrical 400-mesh cordierite honeycomb c...

Embodiment 1

[0043] (1) Determination of the amount of preparation and supported catalyst raw materials

[0044] In the main catalyst of the catalyst prepared in Design Example 1, FeO, La 2 o 3 And the mass percent of ZSM-5 molecular sieve is respectively: 12%: 8%: 80%. CeO in cocatalyst 2 and ZrO 2 The mass percentages are: 80% / 20%. The mass percentage of main catalyst, co-catalyst and coating base material is: 10%:10%:80%. Among coating base materials, SiO 2 、TiO 2 with γ-Al 2 o 3The mass percentages are respectively: 30%: 40%: 30%. Every 100g of catalytic coating requires 10g of polyethylene glycol with an average molecular weight of 20000 and 50g of nitric acid; every 100g of ferrous-La bimetallic modified ZSM-5 molecular sieve needs 300ml of n-hexane.

[0045] Calculate the amount of raw materials required for preparing 2000g of catalytic coating according to the conversion ratio: ferrous chloride [FeCl 2 4H 2 O]66.5g, lanthanum nitrate [La(NO 3 ) 3 ·6H 2 O] 42.5g, ZSM-...

Embodiment 2

[0054] (1) Determination of the amount of preparation and supported catalyst raw materials

[0055] In the main catalyst ferrous-La bimetallic modified ZSM-5 molecular sieve of the prepared catalyst of Design Example 2, FeO, La 2 o 3 And the mass percent of ZSM-5 molecular sieve is respectively: 5%: 3%: 92%. CeO in cocatalyst 2 and ZrO 2 The mass percentages are: 70% / 30%. The mass percent of main catalyst, co-catalyst and coating base material is: 20%:20%:60%. Among coating base materials, SiO 2 、TiO 2 with γ-Al 2 o 3 The mass percentages are respectively: 20%: 70%: 10%. Every 100g of catalytic coating requires 15g of polyethylene glycol with an average molecular weight of 20,000 and 25g of nitric acid; every 100g of ferrous-La bimetallic modified ZSM-5 molecular sieve requires 200ml of n-hexane.

[0056] Calculate the amount of raw materials needed to prepare 2000g of catalytic coating according to the conversion ratio: FeCl 2 4H 2 O 55.4g, La(NO 3 ) 3 ·6H 2 O ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a ferrous modified molecular sieve type diesel engine selective catalytic reduction catalyst. The catalyst is composed of a main catalyst, an auxiliary catalyst, a coating base material and a catalyst carrier, wherein a ferrous-La bimetallic modified ZSM-5 molecular sieve serves as the main catalyst; a CeO2-ZrO2 solid solution serves as the auxiliary catalyst; the coating base material is composed of SiO2, TiO2 and gamma-Al2O3; and a 400-mesh cordierite honeycomb ceramic serves as the catalyst carrier. A preparation process comprises the following steps: preparing and confirming the dosage of the supported catalyst raw materials; preparing the main catalyst, namely, the ferrous-La bimetallic modified ZSM-5 molecular sieve; and preparing the coating slurry and coating. The catalyst is packaged in a diesel engine SCR catalytic converter and is used for catalyzing the SCR reaction of the reducing agent and NOx, so as to realize the purification of NOx pollutants in the exhaust gas of the diesel engine. According to the invention, the environmental harm of the traditional catalyst is reduced, the generation of the secondary pollutants, such as SO3 derivatives, is restrained, and the low-temperature SCR reaction catalytic activity of the catalyst is obviously improved.

Description

technical field [0001] The invention belongs to diesel engine tail gas purification technology, in particular to a catalyst for purifying nitrogen oxides in internal combustion engine exhaust and a preparation method thereof. Background technique [0002] Compared with other fuel power sources, diesel engines are widely used because of their outstanding advantages such as large load capacity, high thermal efficiency, and durability. However, due to the existence of more diffusion combustion in the combustion process, the emissions of NOx (Nitrogen Oxides) and PM (Particulate Matter) in the exhaust of diesel engines are relatively high, which limits its application in areas with stricter air quality requirements. In addition, due to the large amount of NOx and PM emitted in the combustion control of the diesel engine, the emission control effect is difficult to meet the requirements of the National V and National VI emission regulations on diesel engine emissions. Exhaust aft...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B01J29/46B01D53/94B01D53/56
CPCB01D53/9418B01D2251/2067B01D2258/01B01J29/46Y02T10/12
Inventor 宋崇林李博吕刚朱彦涛
Owner TIANJIN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap