Регистрация / Вход
Прислать материал

Advanced synchrotron techniques for operando characterisation of Cu-CHA deNOx catalyst

Name
Kirill
Surname
Lomachenko
Scientific organization
Southern Federal University
Academic degree
PhD
Position
Junior scientist
Scientific discipline
New materials, Manufacturing technologies & Processes
Topic
Advanced synchrotron techniques for operando characterisation of Cu-CHA deNOx catalyst
Abstract
Synchrotron-based spectroscopic techniques, namely XANES, EXAFS and XES, have been applied to shed light on the details of local geometry and electronic structure of catalytically active Cu centers in Cu-exchanged chabazite zeolite under operando conditions. Complemented by extensive theoretical analysis, obtained data provided an insight on the mechanism of the deNOx process catalysed by Cu-CHA zeolite.
Keywords
catalysis, synchrotron, XANES, EXAFS, XES, operando
Summary

The current contribution summarizes our three-year work on Cu-CHA zeolite, which is a very promising material for the selective catalytic reduction of harmful NOx gases from industrial and car exhausts. We have performed several X-ray absorption and X-ray emission experiments at ESRF synchrotron (Grenoble, France) to collect an extensive set of data, allowing to characterize the material in many reaction-relevant states. Particularly, due to the combination of experimental and theoretical work we were able to shed light on the local environment and electronic structure of Cu ions hosted in the cavities of the zeolitic framework after the activation of the material in both inert and oxidative atmospheres, upon interaction with gases of SCR mixture and in operando SCR conditions. This allowed us to develop a consistent mechanism of the SCR reaction and to prove its main stages.