Improved diesel oxidation catalytic converter

A technology of catalyst and catalytic activity, which is applied in the field of oxidation catalyst and exhaust gas purification of heavy-duty trucks. It can solve the problem that the catalyst does not show NO-oxidation activity, and achieve the effect of improving heating-performance

Active Publication Date: 2012-07-11
UMICORE AG & CO KG
View PDF9 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] 2. The oxidation catalyst must be suitable as a "hot catalyst" for the post-particulate filter, that is, it must be able to carry out the oxidative conversion of very large quantities of unburned hydrocarbons in a short period of time, instead of stopping the oxidation reaction at this time
But such catalysts with optimized sulfur tolerance and thus acidic overburden do not show sufficient NO-oxidation activity

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
  • Improved diesel oxidation catalytic converter
  • Improved diesel oxidation catalytic converter
  • Improved diesel oxidation catalytic converter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0063] A catalyst according to the invention was prepared whose total noble metal content and platinum-palladium ratio corresponded to the conventional diesel oxidation catalyst of Comparative Example 1.

[0064] To this end, a first coating is first applied to the ceramic honeycomb body, which has the following composition, based on the volume of the catalyst produced:

[0065] 40g / L silicon-aluminum-mixed oxide containing up to 20% by weight SiO 2

[0066] 0.204g / L precursor platinum nitrate solution

[0067] 0.204g / L precursor palladium nitrate solution

[0068] 15 g / L commercially available beta-zeolite

[0069] The coating represents a coating that does not come into direct contact with the exhaust gases after the catalyst has been produced.

[0070] After drying and calcination of the first layer, a second layer was applied thereon, having the following composition based on the volume of the catalyst produced:

[0071] 40g / L silicon-aluminum-mixed oxide containing u...

Embodiment 2

[0096] Corresponding to the procedure described in Example 1, the catalyst K2 according to the invention was prepared with two superimposed layers of the following composition:

[0097] 1st layer = lower layer = coating not in direct contact with exhaust gases:

[0098] 92g / L silicon-aluminum-mixed oxide containing up to 20% by weight SiO 2

[0099] 0.302g / L precursor platinum nitrate solution

[0100]0.302g / L precursor palladium nitrate solution

[0101] Layer 2 = upper layer = coating in direct contact with exhaust gases:

[0102] 45g / L silicon-aluminum-mixed oxide containing up to 20% by weight SiO 2

[0103] 0.706g / L precursor platinum nitrate solution

[0104] 0.101g / L precursor palladium nitrate solution

Embodiment 3

[0106] Corresponding to the procedure described in Example 1, the catalyst K2 according to the invention was prepared with two superimposed layers of the following composition:

[0107] 1st layer = lower layer = coating not in direct contact with exhaust gases:

[0108] 40g / L silicon-aluminum-mixed oxide containing up to 20% by weight SiO 2

[0109] 0.303g / L precursor platinum nitrate solution

[0110] 0.303g / L precursor palladium nitrate solution

[0111] 15 g / L commercially available beta-zeolite

[0112] Layer 2 = upper layer = coating in direct contact with exhaust gases:

[0113] 45g / L silicon-aluminum-mixed oxide containing up to 20% by weight SiO 2

[0114] 0.706g / L precursor platinum nitrate solution

[0115] 0.101g / L precursor palladium nitrate solution

[0116] Figure 6 shows that the addition of zeolite to the coating not in direct contact with the exhaust gas has an effect on the NO of the catalyst 2 - Yield was not significantly affected.

[0117] Howe...

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 relates to a catalytic converter for purifying the exhaust gases of diesel engines, in particular an oxidation catalytic converter, which is particularly effective for the purification of the exhaust gases of heavy goods vehicles if further exhaust-gas purification units such as for example a particle filter and / or a nitrogen oxide reduction catalytic converter are connected downstream thereof. The catalytic converter contains two catalytically active coatings which differ in terms of their composition and of which only one is in direct contact with the outflowing exhaust gas. The coating (1) which is in direct contact with the outflowing exhaust gas is platinum-rich and, overall, contains more high-grade metal (platinum and palladium) than the coating (2) which is not in direct contact with the outflowing exhaust gas.; The platinum-rich coating (1) exhibits a markedly intense oxidation action in particular with regard to NO oxidation, while the coating (2) which is not in direct contact with the outflowing exhaust gas serves to ensure good heat-up performance of the catalytic converter.

Description

technical field [0001] The invention relates to a catalyst for cleaning the exhaust gas of a diesel engine, in particular an oxidation catalyst, which is particularly suitable for cleaning heavy-duty vehicles in the case of the subsequent arrangement of further exhaust gas cleaning units such as particle filters and / or nitrogen oxide-reduction catalysts exhaust gas. Background technique [0002] The crude exhaust gas of a diesel engine contains carbon monoxide CO, hydrocarbons HC and nitrogen oxides NO x In addition, a relatively high oxygen content of up to 15% by volume is contained. In addition, particulate emissions are included, consisting mainly of soot residues and optionally organic agglomerates, and resulting from partially incompletely burned fuel in the cylinders. Harmful gases carbon monoxide and hydrocarbons can easily be rendered harmless by oxidation over suitable oxidation catalysts. A diesel particulate filter with or without a catalytically active coatin...

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
IPC IPC(8): B01D53/94B01J23/44B01J35/00B01J37/02F01N3/10
CPCB01D2257/702B01D2255/2092B01D2255/1021B01D2257/502B01J35/0006B01J29/7415F01N3/10B01D53/944B01D2258/012F01N2510/06B01J37/0246B01D2255/9022B01J21/12B01J37/0244B01D2255/1023B01D53/9477B01J23/44Y02A50/20B01J35/19
Inventor F-W·舒特泽S·佛朗茨G·杰斯克C·亨斯特
Owner UMICORE AG & CO KG
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