Recent progress in performance optimization of Cu-SSZ-13 catalyst for selective catalytic reduction of NO x

Abstract

Nitrogen oxides (NO _x ), which are the major gaseous pollutants emitted by mobile sources, especially diesel engines, contribute to many environmental issues and harm human health. Selective catalytic reduction of NO _x with NH₃ (NH₃-SCR) is proved to be one of the most efficient techniques for reducing NO _x emission. Recently, Cu-SSZ-13 catalyst has been recognized as a promising candidate for NH₃-SCR catalyst for reducing diesel engine NO _x emissions due to its wide active temperature window and excellent hydrothermal stability. Despite being commercialized as an advanced selective catalytic reduction catalyst, Cu-SSZ-13 catalyst still confronts the challenges of low-temperature activity and hydrothermal aging to meet the increasing demands on catalytic performance and lifetime. Therefore, numerous studies have been dedicated to the improvement of NH₃-SCR performance for Cu-SSZ-13 catalyst. In this review, the recent progress in NH₃-SCR performance optimization of Cu-SSZ-13 catalysts is summarized following three aspects: 1) modifying the Cu active sites; 2) introducing the heteroatoms or metal oxides; 3) regulating the morphology. Meanwhile, future perspectives and opportunities of Cu-SSZ-13 catalysts in reducing diesel engine NO _x emissions are discussed.

Keywords: Cu-SSZ-13 catalyst; hydrothermal stability; low-temperature activity; poisoning resistance; selective catalytic reduction.