Quasi- quantification of Cu() ions in Cu-SSZ-13 catalyst by an NH temperature-programmed reduction method

A quasi- operando NH 3 temperature-programmed reduction method (NH 3 -TPR), with N 2 :Cu = 1:1, is developed to quantify total Cu( ii ) ions in Cu-SSZ-13 quenched from SCR-relevant reactions, and its accuracy is confirmed by in situ EPR. [Cu(OH)] + -Z and Cu 2+ -2Z can be further distinguished by NH 3 reduction temperatures, and their different reducibility in SCR is revealed. A quasi- operando NH 3 -TPR method can quantify two Cu( ii ) ions ([Cu(OH)] + -Z and Cu 2+ -2Z) in Cu-SSZ-13 and compare their reducibility in SCR.