Elucidating the Significance of Nitrate Speciation in Small-pore Cu-containing Zeolitic Materials for the NH3-SCR reaction
NOx gases are a serious pollution problem that pose as a hazard to human respiratory function and environmental ecosystems. Reduction of NOx emission has been a central theme in a significant amount of recent industrial and academic research effort.1 One promising chemical innovation is the selective catalytic reduction (SCR) reaction, which utilises a catalytic material to convert nitrogen oxides in the presence of a reductant such as ammonia into a benign mixture of nitrogen gas and water. Small pore Cu-zeolites have been identified as excellent catalysts in the SCR reaction, being lauded for their unrivalled NOx conversion.2 One challenge arising in NH3-SCR is the unwanted formation of N2O. Harmful indications following long-term exposure2 and a global warming potential almost 300 times that of CO2 mean that N2O will inevitably become the subject of increasingly exacting legislation beyond Euro6.1 This work turns a critical eye on the catalysts themselves and explores the correlation between N2O formation and the nature of copper speciation throughout the catalyst.3 To demonstrate this correlation, the Cu-zeolites were studied using an ambitious combination of two synchrotron techniques at the Diamond Light Source; the x-ray nanoprobe on I14 and the multimode infrared imaging and microspectroscopy (MIRIAM) beam on B22.
1. Mauzerall, D.; Sultan, B.; Kim, N.; Bradford, D. Atmos. Environ. 2005, 39, 2851–2866.
2. Beale, A. M.; Gao, F.; Lezcano-Gonzalez, I.; Peden, C. H. F.; Szanyi, J. Chem. Soc. Rev. 2015, 44, 7371–7405.
3. Deka, U.; Lezcano-Gonzalez, I., Weckhuysen, B. M.; Beale, A. M. ACS Catal. 2013, 3, 413–427.
Dr. Leila Negahdar is Marie-Curie Fellow at UCL Chemistry. Before coming to UCL in October 2019, she was research associate with Prof Richard Catlow at Cardiff University and UK Catalysis Hub. Prior to this, she was postdoctoral research associate at RWTH Aachen University in Germany (2018), and postdoctoral research fellow in department of Inorganic Chemistry and Catalysis at Utrecht University Netherlands, working with Prof Bert M. Weckhuysen (2014-2016). She received her master’s degree in Chemical Engineering from Technical University of Dortmund in Germany and PhD degree in Chemistry from RWTH Aachen University under supervision of Prof Regina Palkovits. Her research interests include mainly reaction engineering, catalytic kinetics and mechanism and operando spectroscopy of catalytic surface reactions.
Event Contact Name:
Dr Francisco R Garcia Garcia