Trace mono-atomically dispersed rhodium on zeolite-supported cobalt catalyst for the efficient methane oxidation

• Published in: Communications chemistry Vol. 1; no. 1
• Main Authors: Hou, Yuhui, Nagamatsu, Shinichi, Asakura, Kiyotaka, Fukuoka, Atsushi, Kobayashi, Hirokazu
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.08.2018; Nature Publishing Group
• Subjects: 639/4077/4082/4090; 639/638/675; 639/638/77/887; Base metal; Carbon monoxide; Catalysis; Catalysts; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Cobalt oxides; Coking; Deactivation; Dispersion; Durability; Methane; Oxidation; Platinum; Rhodium; Selectivity; Stainless steels; Synthesis gas; Zeolites
• ISSN: 2399-3669; 2399-3669
• DOI: 10.1038/s42004-018-0044-9

The partial oxidation of methane is a promising method for the efficient production of syngas. To implement this process using common stainless steel reactors, an inexpensive catalyst that functions at 650 °C or below is necessary. However, base metal catalysts typically require much higher temperatures, and they are deactivated by re-oxidation and coke formation. Here we report that modification of a zeolite-supported 3 wt% cobalt catalyst with a trace amount of mono-atomically dispersed rhodium (0.005 wt%) dramatically improves catalytic performance and durability. Cobalt/mordenite is nearly inactive due to the oxidation of cobalt, but the catalyst modified with rhodium continuously gives 85–86% methane conversion and 90–91% CO selectivity with an H 2 /CO ratio of 2.0 without serious coking at 650 °C. During the reaction, mono-atomically dispersed rhodium converts cobalt oxide to Co 0 active species via hydrogen spillover. Use of the zeolite support is key to the high catalytic performance. Partial oxidation of methane is an efficient route to syngas, and would benefit from base metal catalysts which operate below 650 °C. Here, the authors demonstrate that modification of a zeolite-supported cobalt catalyst with trace rhodium improves both catalyst activity and durability under such conditions.