Impact of PtOx formation in diesel oxidation catalyst on NO2 yield during driving cycles

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F17%3A43915435" target="_blank" >RIV/60461373:22340/17:43915435 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.ces.2016.10.011" target="_blank" >http://dx.doi.org/10.1016/j.ces.2016.10.011</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ces.2016.10.011" target="_blank" >10.1016/j.ces.2016.10.011</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Impact of PtOx formation in diesel oxidation catalyst on NO2 yield during driving cycles

Popis výsledku v původním jazyce

Operation of a platinum-based diesel oxidation catalyst under lean conditions leads to the partial transformation of metallic Pt sites into platinum oxides (PtOx) with considerably lower NO oxidation rate. The varying NO2 yield depending on PtOx coverage significantly influences the performance of other devices following in a diesel exhaust aftertreatment line: particulate filter (soot oxidation) and SCR or LNT catalyst (NOx reduction). In this paper, we present a global kinetic model of a diesel oxidation catalyst, including PtOx formation induced by reactions with O2 and NO2, PtOx reduction by CO, hydrocarbons and NO, and PtOx thermal decomposition, and use it to reveal the extent of NO2 yield variation in four standard driving cycles for passenger car emission tests: NEDC, FTP, US06 and SC03. During a single driving cycle, the NO2 yield decreases by 3?10% relative to the original level of the reduced catalyst. The PtOx formation is a slow process and stabilizes only after approximately four repeated driving cycles. The stabilized NO2 yield is 7?27% (relative) lower than with the reduced catalyst, depending mainly on the history of operating temperatures. The largest variation is observed around 250?300 °C. At lower temperatures, PtOx are partly reduced during CO and hydrocarbon peaks in the engine exhaust during dynamic operation. At higher temperatures, PtOx start to decompose and NO oxidation becomes limited by equilibrium.

Název v anglickém jazyce

Impact of PtOx formation in diesel oxidation catalyst on NO2 yield during driving cycles

Popis výsledku anglicky

Operation of a platinum-based diesel oxidation catalyst under lean conditions leads to the partial transformation of metallic Pt sites into platinum oxides (PtOx) with considerably lower NO oxidation rate. The varying NO2 yield depending on PtOx coverage significantly influences the performance of other devices following in a diesel exhaust aftertreatment line: particulate filter (soot oxidation) and SCR or LNT catalyst (NOx reduction). In this paper, we present a global kinetic model of a diesel oxidation catalyst, including PtOx formation induced by reactions with O2 and NO2, PtOx reduction by CO, hydrocarbons and NO, and PtOx thermal decomposition, and use it to reveal the extent of NO2 yield variation in four standard driving cycles for passenger car emission tests: NEDC, FTP, US06 and SC03. During a single driving cycle, the NO2 yield decreases by 3?10% relative to the original level of the reduced catalyst. The PtOx formation is a slow process and stabilizes only after approximately four repeated driving cycles. The stabilized NO2 yield is 7?27% (relative) lower than with the reduced catalyst, depending mainly on the history of operating temperatures. The largest variation is observed around 250?300 °C. At lower temperatures, PtOx are partly reduced during CO and hydrocarbon peaks in the engine exhaust during dynamic operation. At higher temperatures, PtOx start to decompose and NO oxidation becomes limited by equilibrium.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20401 - Chemical engineering (plants, products)

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Chemical Engineering Science

ISSN

0009-2509

e-ISSN

—

Svazek periodika

158

Číslo periodika v rámci svazku

neuveden

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

7

Strana od-do

181-187

Kód UT WoS článku

000389068900018

EID výsledku v databázi Scopus

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