Unravelling the key factors in the chlorine-promoted epoxidation of ethylene over a silver-copper oxide nanocatalyst

Urbiztondo, Miguel ; Ramirez, Adrian ; Hueso, Jose L. (Universidad de Zaragoza) ; Santamaria, Jesus (Universidad de Zaragoza) ; Ruiz-Salvador, A. Rabdel ; Hamad, Said

Resumen: Ethylene oxide is one of the most important raw materials in the chemical industry, with an annual production close to 35 million metric tons. Despite its importance, to date, no metal has been found that can compete with the original silver bulk material catalyst discovered in 1931. Recently, a few copper and copper-silver based nanostructures have demonstrated remarkable selectivity and activity, especially when coupled with an industrial chlorine promoter. The present work evaluates the mechanistic role of chlorine as an active promoter of the selective oxidation of ethylene to ethylene oxide in the presence of a silver-copper oxide hybrid nanocatalyst (AgCuO). Experimental kinetic studies combined with density functional theory (DFT) calculations provide insight into the influence that Ag/CuO-supported chlorine atoms have over the ethylene epoxidation reaction. Remarkably, the typically described indirect route via the formation of an oxametallacycle (OMC) is also accompanied by a direct route. Furthermore, the presence of chlorine seems to facilitate a more favorable adsorption energy for ethylene oxide (EO) than for acetaldehyde (AA), the main reaction by-product. As a result, complete oxidation of EO can be further prevented in the presence of this AgCuO hybrid heteronanostructure.

Idioma: Inglés

DOI: 10.1039/d2nr00702a

Año: 2022

Publicado en: Nanoscale 14, 19 (2022), 7332-7340
ISSN: 2040-3364

Factor impacto JCR: 6.7 (2022)

Categ. JCR: MATERIALS SCIENCE, MULTIDISCIPLINARY rank: 83 / 343 = 0.242 (2022) - Q1 - T1
Categ. JCR: PHYSICS, APPLIED rank: 27 / 160 = 0.169 (2022) - Q1 - T1
Categ. JCR: CHEMISTRY, MULTIDISCIPLINARY rank: 43 / 178 = 0.242 (2022) - Q1 - T1
Categ. JCR: NANOSCIENCE & NANOTECHNOLOGY rank: 37 / 107 = 0.346 (2022) - Q2 - T2

Factor impacto CITESCORE: 13.6 - Materials Science (Q1)

Factor impacto SCIMAGO: 1.62 - Nanoscience and Nanotechnology (Q1) - Materials Science (miscellaneous) (Q1)

Financiación: info:eu-repo/grantAgreement/EC/ERC/267626/EU/Microwave-Microwave-Assisted Microreactors: Development of a highly efficient gas phase contactor with direct catalyst heating /HECTOR
Financiación: info:eu-repo/grantAgreement/ES/MCIU/PID2019-110430GB-C22

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Ingeniería Química (Dpto. Ing.Quím.Tecnol.Med.Amb.)