The influence of C1 and C2 organic reducing agents on catalytic properties of Co(II)-single site BEA zeolite in SCR of NO
Abstract
CoSiBEA zeolite with 0.9 wt.% Co is prepared in acidic (pH = 2.5) condition by a two-step postsynthesis method which allows to incorporate cobalt into framework zeolite as isolated tetrahedral Co(II) species, as evidenced by XRD and diffuse reflectance UV-vis. As obtained Co(II)-single site zeolite catalyst with isolated and framework Co centres are active in SCR of NO process with C2 (ethanol and ethylene) reducing agents, with selectivity toward N2 exceeding 90% in the temperature range from 575 to 675 K for maximum NO conversion about 70 and 65% at 625 K for ethanol and ethylene, respectively. In contrast, this catalyst is much less active with C1 (methanol and methane) reducing agents, with maximum selectivity toward N2 not exceeding 22% with methanol and 18% with methane for maximum NO conversion of 20 and 18%, respectively.