Effect of K-Modified Blue Coke-Based Activated Carbon on Low Temperature Catalytic Performance of Supported Mn–Ce/Activated Carbon

[Image: see text] To clarify the K modified effects over activated carbon (AC) supported Mn–Ce oxide catalysts, several Mn–Ce/AC and xK–Mn–Ce/AC mixed oxide catalysts prepared via an impregnation method supported on AC were investigated for low-temperature selective catalytic reduction (SCR) of NO with NH(3) in the simulated sintering flue gas. The Mn–Ce/AC catalyst with a K loading of 8% showed the highest catalytic activity, corresponding to 92.1% NO conversion and 92.5% N(2) selectivity at 225 °C with a space velocity of 12,000 h(–1). Furthermore, the 0.08K–Mn–Ce/AC catalyst exhibited better resistance to SO(2) and H(2)O than Mn–Ce/AC, which could convert 72.3% and 74.1% of NO at the presence of 5% SO(2) and H(2)O, respectively. After K modification, the relative ratios of Mn(4+)/Mn(n+) as well as Ce(3+)/Ce(n+) and surface adsorbed oxygen increased. Additionally, the reduction performance of the catalyst was improved obviously, and both acid strength and quantity of acid sites increased significantly after the K species were introduced in Mn–Ce/AC. Especially, the NO adsorption capacity of the catalyst was enhanced, which remarkably promoted the denitration efficiency and SO(2) resistance. The SCR of NO with NH(3) on K–Mn–Ce/AC catalysts followed the L-H mechanism.