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Indexed by:期刊论文

Date of Publication:2017-02-01

Journal:CHEMCATCHEM

Included Journals:SCIE、EI、Scopus

Volume:9

Issue:3

Page Number:505-510

ISSN No.: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.