Cu-Mn bimetal ion-exchanged SAPO-34 as an active SCR catalyst for removal of NOx from diesel engine exhausts

Mn/SAPO-34, Cu/SAPO-34, and Cu-Mn/SAPO-34 were prepared through ion-exchanged method and used to remove NO from diesel engine exhausts. The original crystal and physical structure of SAPO-34 is maintained in the catalysts. The ion-exchanged amount of Cu in Cu-Mn/SAPO-34 is higher than that in Cu/SAPO-34, and more Cu+ is formed as active center for low-temperature selective catalytic reduction (SCR). After co-doping of Cu and Mn, the acidic strength of the catalyst increases and formation of NH3NOx surface intermediate species is promoted. Cu-Mn/SAPO-34 exhibits high deNO(x) activity, hydrothermal stability, and resistance to hydrocarbon (HC). (C) 2016 Elsevier B.V. All rights reserved.