NOx ADSORBER CATALYST

a technology of nox and adsorber, which is applied in the direction of physical/chemical process catalysts, other chemical processes, separation processes, etc., can solve the problems of inefficient storage function low efficiency of system below operating temperature, and deactivation of nosub>x /sub>adsorber catalysts

Inactive Publication Date: 2020-07-02
JOHNSON MATTHEY PLC
View PDF0 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The patent describes a new NOx adsorber catalyst for treating emissions from lean burn engines, such as diesel engines. The catalyst includes a support material, one or more platinum group metals, and a NOx storage material. The support material can be alumina or a mixed oxide comprising alumina. The one or more platinum group metals can be a mixture or alloy of platinum and palladium. The NOx storage material can be a lanthanum-doped ceria. The patent also describes a method of making the NOx storage material by spray-drying ceria particles and heating them. The patent also describes an emission treatment system that includes the NOx adsorber catalyst and a lean-burn engine. The technical effects of the invention include improved NOx conversion and reduced emissions from lean burn engines.

Problems solved by technology

However, these systems are relatively inefficient below their operating temperature (the “cold start” period).
), the NOx storage function of these catalysts is inefficient and continues to be an area of catalyst development in need of improvement.
The deactivation of NOx adsorber catalysts by sulfur, which can be present in fuels or engine lubricating oil, is also a problem, particularly under lower temperature conditions at which it may be challenging to thermally desulfate the catalyst.

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

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0160]Preparation of Al2O3PGM Ce

[0161]1.5 g / in3 Al2O3 is made into a slurry with distilled water and then milled to a d90 of 13-15 μm. To the slurry, 94 g / ft3 Pt malonate and 19 g / ft3 Pd nitrate solution is then added, and stirred until homogenous. The Pt / Pd is allowed to adsorb onto the Al2O3 support for 1 hour.

[0162]To this is then added 3 g / in3 high surface area ceria and 0.2 g / in3 alumina binder, and stirred until homogenous to form a washcoat.

[0163]The washcoat is then coated onto a ceramic or metallic monolith using standard procedures, dried at 100° C. and calcined at 500° C. for 45 mins.

[0164]The Ce is present at a loading of about 51.9 wt % (51.1 mol %).

example 2

[0165]Preparation of [Al2O3.La(13.0 wt %)] PGM Ce (10.7 mol % Al2O3.La)

[0166]Prepared as in Example 1, but using [Al2O3.La] (prepared according to general preparation (2) above).

[0167]The Ce is present at a loading of about 49.1 wt % (49.9 mol %) The La is present at a loading of about 4.6% (4.8 mol %).

example 3

[0168]Preparation of [Al2O3.La(26.6 wt %)] PGM Ce (24.9 mol % Al2O3.La)

[0169]Prepared as in Example 1, but using [Al2O3.La] (prepared according to general preparation (2) above).

[0170]The Ce is present at a loading of about 45.4 wt % (48.1 mol %) The La is present at a loading of about 10.8 wt % (11.5 mol %).

Experimental Results

[0171]Catalytic activity was determined using a synthetic gas bench test. The cores were tested in a simulated catalyst activity testing (SCAT) gas apparatus using the inlet gas mixture in Table 1. The test consisted of five cycles of 300 seconds lean / 16 seconds rich, at a space velocity (SV) of 40,000 h−1.

TABLE 1LeanRichO2 (%)120.9CO2 (%)610H2O (%)612NO (ppm)200100C3H6 (ppm as C1)5003000CO (ppm)150021000H2 (ppm)—7500

Results

[0172]The results from one representative cycle of the SCAT test are shown in Table 2 below.

TABLE 2TemperatureNOx conversion (%)(° C.)Example 1Example 2Example 315000017501618200153725250466448

[0173]From Table 2 it can be seen that Example...

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

PropertyMeasurementUnit
temperatureaaaaaaaaaa
operating temperatureaaaaaaaaaa
temperaturesaaaaaaaaaa
Login to View More

Abstract

A NOx adsorber catalyst and its use in an emission treatment system for internal combustion engines, is disclosed. The NOx adsorber catalyst comprises a first layer consisting essentially of a support material, one or more platinum group metals disposed on the support material, and a NOx storage material.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This U.S. non-provisional patent application claims priority benefit of GB Patent Applications 1610160.2, filed Jun. 10, 2016, and 1704901.6, filed Mar. 28, 2017, the disclosures of which are incorporated herein by reference in their entirety for all purposesFIELD OF THE INVENTION[0002]The invention relates to a NOx adsorber catalyst, a method of making a NOx storage material, and emission systems for internal combustion engines comprising the NOx adsorber catalyst.BACKGROUND OF THE INVENTION[0003]Internal combustion engines produce exhaust gases containing a variety of pollutants, including nitrogen oxides (“NOx”), carbon monoxide, and uncombusted hydrocarbons, which are the subject of governmental legislation. Increasingly stringent national and regional legislation has lowered the amount of pollutants that can be emitted from such diesel or gasoline engines. Emission control systems are widely utilized to reduce the amount of these pol...

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 & AuthorityApplications(United States)
IPC IPC(8): F01N3/08B01J23/00B01J20/28B01J20/30B01J37/02B01J20/06B01J20/08B01D53/94B01J20/32B01J20/02F01N3/20F01N3/10B01J37/08B01J37/00B01J23/63
CPCB01D53/9459B01J37/0244B01J37/0201B01J37/0248B01D2255/9155B01D2255/915Y02T10/22B01D2255/91B01D2255/902B01J37/0045B01J37/0203F01N3/101B01D2255/2065B01D2255/1023B01D2255/2063B01D53/9454B01D2258/012B01J37/0234B01J35/04B01D2255/1021B01J20/06B01D53/9422B01J20/08B01J23/63F01N2370/02F01N3/035B01D53/9418F01N2510/06B01J23/005B01D2255/405F01N3/0814F01N2510/0684F01N3/0842B01J20/0207B01J20/0225B01J37/08Y02T10/24B01J2523/00B01J20/28042B01J20/3085B01J20/3204F01N3/2066B01J20/3236F01N2570/14Y02T10/12B01J35/56B01J2523/31B01J2523/3706B01J2523/3712B01J2523/824B01J2523/828B01J2523/22B01J2523/3725B01J2523/25B01J37/0009B01D53/9409B01D53/9413F01N3/10
InventorARMITAGE, ANDREWDURAN MARTIN, DESIREEMAKSYMOWICZ, REBECCAMILLINGTON, PAUL JAMESPHILLIPS, PAUL RICHARDRAJARAM, RAJ RAOREID, STUART DAVIDSWALLOW, DANIEL
OwnerJOHNSON MATTHEY PLC