Collect. Czech. Chem. Commun. 1998, 63, 1781-1792
https://doi.org/10.1135/cccc19981781

Siting and Reactivity of the Co Ions in Ferrierite in Selective Catalytic Reduction of NO with CH4

Dalibor Kaucký, Jiří Dědeček, Alena Vondrová, Zdeněk Sobalík and Blanka Wichterlová

J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, 182 23 Prague 8

Abstract

Catalytic activity of Co ions in CoNaK- and CoH-ferrierites in selective catalytic reduction of NO with methane depending on Co loading was investigated. The previously determined distribution of the exchanged Co ions in Co-ferrierites at three different cationic sites, differring in coordination of the Co ions to framework oxygens, has been utilized to analyze catalytic activity of the Co ions. The type of coordination of the Co ions dramatically affects their reactivity in the selective catalytic reduction of NO with methane. The Co ions coordinated to four framework oxygens of the wall of the main channel exhibit the highest activity, while the Co ions placed in a "boat shape", the most packed site of ferrierite show the lowest activity.

Keywords: Selective catalytic reduction of NO with methane; Co-zeolite; Co-ferrierite; Nitric oxide; Zeolites; Heterogeneous catalysis; Cobalt.