Effective Utilization of Pt Catalyst in Three-Way Catalytic System by Employing Calcined Ceria with Alumina Mitsui Mining and Smelting Company, Limited

Format:

Book

Conference/Event

Author/Creator:

Morita, Itaru, author.

Contributor:

Endo, Yoshinori

Haneda, Masaaki

Isayama, Akihiro

Iwashina, Katsuya

Nagao, Yuki

Saeki, Shohei

Tanaka, Hiroki

Wakabayashi, Takashi

Conference Name:

WCX SAE World Congress Experience (2024-04-16 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2024

Summary:

To satisfy the stringent regulations for exhaust gas emissions from gasoline-powered vehicles, large amounts of Rh and Pd have often been employed in three-way catalysts (TWCs) as the main active components. On the other hand, Pt-based TWCs are not often used in gasoline vehicles because Pt is readily sintered by its exhaust gases at approximately 1000 °C [1, 2]. In general, Pt-based TWCs must be located away from large thermal loads to maintain the active sites for gas purification. Based on this background, we previously reported that employing a small amount of CeO2 calcined at 1000 °C (cal-CeO2) in Pt-based TWCs was one of the most effective approaches for improving the catalytic activity without increasing the amount of Rh and Pd [3]. The effect of cal-CeO2 was attributed to the higher redox performance and Pt dispersion derived from the strong interactions between Ce and Pt. Therefore, the resulting Pt-based TWCs exhibited high catalytic performance, despite the low specific surface area (SSA) of cal-CeO2 due to high temperature calcination. In this study, we demonstrated that the low SSA of cal-CeO2 can be easily improved by adding Al2O3. The SSA of Al2O3-modified CeO2 calcined at 1000 °C (Al2O3-CeO2) was 45% higher than that of cal-CeO2 owing to the inhibition of CeO2 sintering by Al2O3. In addition, the interactions with Pt were significantly improved, leading to higher redox performance and Pt dispersion compared to the corresponding Pt catalyst supported on cal-CeO2. To determine the effects on the catalytic performance, vehicle evaluations were performed after aging treatment by gasoline-powered engine. Al2O3-CeO2 was employed in a Rh/Pt double-layered TWC placed at the rear bed in a close-coupled system. The results of the FTP mode test cycles on a dynamometer indicate that the addition of Al2O3-CeO2 to Rh/Pt double-layered TWCs is clearly more effective for suppressing exhaust gas emissions than the addition of cal-CeO2

Notes:

Vendor supplied data

Publisher Number:

2024-01-2133

Access Restriction:

Restricted for use by site license