Greenaway Alex G, Lezcano-Gonzalez Ines, Agote-Aran Miren, Gibson Emma K, Odarchenko Yaroslav, Beale Andrew M
1Department of Chemistry, UCL, 20 Gordon Street, London, WC1H 0AJ UK.
2Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell, Didcot, OX11 0FA UK.
Top Catal. 2018;61(3):175-182. doi: 10.1007/s11244-018-0888-3. Epub 2018 Jan 19.
The small pore zeolite chabazite (SSZ-13) in the copper exchanged form is a very efficient material for the selective catalytic reduction by ammonia (NH) of nitrogen oxides (NOx) from the exhaust of lean burn engines, typically diesel powered vehicles. The full mechanism occurring during the NH-SCR process is currently debated with outstanding questions including the nature and role of the catalytically active sites. Time-resolved operando spectroscopic techniques have been used to provide new level of insights in to the mechanism of NH-SCR, to show that the origin of stable Cu(I) species under SCR conditions is potentially caused by an interaction between NH and the Cu cations located in eight ring sites of the bulk of the zeolite and is independent of the NH-SCR of NOx occurring at Cu six ring sites within the zeolite.
铜交换形式的小孔菱沸石（SSZ - 13）是一种非常有效的材料，用于通过氨（NH₃）选择性催化还原稀薄燃烧发动机（通常是柴油动力车辆）尾气中的氮氧化物（NOₓ）。目前，NH₃ - SCR过程中发生的完整机制存在争议，包括催化活性位点的性质和作用等突出问题。时间分辨原位光谱技术已被用于为NH₃ - SCR机制提供新的见解水平，以表明SCR条件下稳定的Cu(I)物种的起源可能是由NH₃与位于沸石主体八元环位点的Cu阳离子之间的相互作用引起的，并且与沸石内Cu六元环位点处发生的NOₓ的NH₃ - SCR无关。
