Desilication tuning of In/Hβ catalysts for sulfur- and steam-resistant CH4-SCR of NO

Mesoporous In/Hβ-X series catalysts were prepared by desilication method with tetrapropylammonium hydroxide (TPAOH) and indium incorporation for selective catalytic reduction of NO with methane (CH4-SCR). The post desilication treatment conditions for preparing In/Hβ-X were optimized. Etching time is the most important desilication parameter influencing the resulting CH4-SCR performance of the catalyst. The In/Hβ-3 sample which was etched for 3 h presents the highest NOx conversion, 22% higher than In/H-Beta counterparts using commercial microporous beta. Obvious analysis reveals that besides generating mesopores, controlled desilication can modulate the proportion of InO+ active sites and surface oxygen species, allowing more active sites to be exposed. •Mesoporous beta zeolite was fast synthesized by desilication with TPAOH.•Portion of InO+ greatly contributed to the high catalytic efficiency.•Controlled etching modulated the proportion of InO+ active sites and surface oxygen.