NOx conversion and selectivity in multi-layer and sequential DOC-LNT automotive exhaust catalysts: Influence of internal transport

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F17%3A43914113" target="_blank" >RIV/60461373:22340/17:43914113 - isvavai.cz</a>

Alternative codes found

RIV/49777513:23640/17:43950080

Result on the web

<a href="http://dx.doi.org/10.1016/j.cej.2017.05.129" target="_blank" >http://dx.doi.org/10.1016/j.cej.2017.05.129</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.cej.2017.05.129" target="_blank" >10.1016/j.cej.2017.05.129</a>

Result language

angličtina

Original language name

NOx conversion and selectivity in multi-layer and sequential DOC-LNT automotive exhaust catalysts: Influence of internal transport

Original language description

In order to pass strict emission standards, automobiles with internal combustion engines need to be equipped with complex exhaust gas aftertreatment systems. For example, Diesel engines are usually fitted with an oxidation catalyst (DOC), deNOx catalyst (either SCR or lean NOx trap ? LNT) and a particulate filter. Integrating them into a single multi-functional device saves space, cost and weight while improving heat management during cold starts as well. This work investigates a compact DOC+LNT converter combining both catalyst types in a single device ? porous layer of a DOC catalyst is added on top of a LNT washcoat. The performance of this dual-layer converter is compared with traditional single-layer DOC and LNT coated on two separate monoliths in series. Laboratory reactor experiments showed that the performance of the dual-layer sample was affected by transport limitations ? mainly internal diffusion through the catalytic layers. An increased NOx slip was observed during NOx adsorption in the dual-layer sample. The lower amount of stored NOx was however more than compensated during NOx reduction at lower temperatures near the light-off, where the compact dual-layer monolith exhibited higher efficiency of NOx reduction and lower selectivity to N2O during rich regeneration periods. This was attributed to the fact that the NOx released from the bottom LNT layer has to pass through the top DOC layer where it can further react with the reducing agents from the rich feed. At higher temperatures, the two single-layer monoliths outperformed the compact dual-layer monolith.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

20401 - Chemical engineering (plants, products)

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Chemical Engineering Journal

ISSN

1385-8947

e-ISSN

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Volume of the periodical

329

Issue of the periodical within the volume

329

Country of publishing house

CH - SWITZERLAND

Number of pages

7

Pages from-to

128-134

UT code for WoS article

000410765700013

EID of the result in the Scopus database

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