Issue 23, 2017

Rh-promoted mixed oxides for “low-temperature” methane partial oxidation in the absence of gaseous oxidants

Abstract

Compared to conventional reforming, chemical looping reforming (CLR), which partially oxidizes methane in the absence of gaseous oxidants such as steam or oxygen, offers a simpler and potentially more efficient route for syngas generation. This is achieved by cyclic removal and replenishment of active lattice oxygen in oxygen carrier particles, a.k.a. redox catalysts. With redox catalysts being at the heart of CLR, their activity and selectivity are crucial for the CLR performance. While many redox catalysts have been developed, their activities toward methane partial oxidation (POx), especially at relatively low temperatures, are often limited due to the high activation energy for the migration and removal of lattice oxygen. Moreover, syngas selectivity is often less than ideal due to the non-selective nature of the surfaces for many oxides. To address these limitations, we investigated the effects of promoting the catalytic activity of oxide surfaces for two redox catalysts: CaMnO3 and LaCeO3. Our findings indicate that promoting mixed oxides with a small amount of Rh can lower the onset temperature of methane POx by as much as 300 °C (0.5 wt% Rh loading). Over 93% syngas selectivity and 7.9 mmol of syngas per gram of redox catalyst were obtained for a highly stable, Rh promoted CaMnO3 at 600 °C, making it a promising redox catalyst for methane POx under a cyclic redox scheme.

Graphical abstract: Rh-promoted mixed oxides for “low-temperature” methane partial oxidation in the absence of gaseous oxidants

Supplementary files

Article information

Article type
Paper
Submitted
15 2月 2017
Accepted
11 4月 2017
First published
06 6月 2017

J. Mater. Chem. A, 2017,5, 11930-11939

Rh-promoted mixed oxides for “low-temperature” methane partial oxidation in the absence of gaseous oxidants

A. Shafiefarhood, J. Zhang, L. M. Neal and F. Li, J. Mater. Chem. A, 2017, 5, 11930 DOI: 10.1039/C7TA01398A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements