Release Time:2019-03-12  Hits:

Indexed by: Journal Article

Date of Publication: 2017-02-01

Journal: CHEMCATCHEM

Included Journals: Scopus、EI、SCIE

Volume: 9

Issue: 3

Page Number: 505-510

ISSN: 1867-3880

Key Words: acetaldehyde; copper; dehydrogenation; graphitic-N; porous carbon

Abstract: The dehydrogenation of bioethanol to acetaldehyde and hydrogen is a sustainable process, owing to the atom-economical transformation and easy separation of the products. However, oxide-supported Cu catalysts show a low selectivity to acetaldehyde because of considerable side reactions caused by their oxygen-rich surfaces. A conventional carbon-supported Cu catalyst shows high selectivity, but is quickly deactivated owing to the migration and agglomeration of copper particles. Here, we have produced a highly porous nitrogen-rich carbon support that contains 6.2wt% N and can nicely disperse and stabilize Cu nanoparticles (similar to 6.3nm). If used for ethanol dehydrogenation, approximately 98% selectivity to acetaldehyde has been achieved, with excellent anti-agglomeration ability for as long as 500min. X-ray photoelectron spectroscopy (XPS) data prove that electrons transfer to the Cu particles from the N sites. Theoretical calculations further show that nitrogen sites enhance the adsorption of Cu-20 clusters and can stabilize them against coalescence and that graphitic-N sites (approximately 40% of total N content) are the most significant.