Suitability of pyrolusite as additive to activated coke for low‐temperature NO removal

Abstract

AbstractBACKGROUNDPyrolusite was used as additive to prepare coal‐based activated coke (AC) for low‐temperature NO removal. The pyrolusite modified AC was prepared by a blending method, and the denitrification performance was evaluated in a lab‐scale simulated fixed‐bed reactor.RESULTSThe blending of pyrolusite promoted the specific surface area and pore structure of AC, even though the MnO2 and Fe2O3 showed inhibitory effects when blended separately. Both the basic and acid sites of AC‐Mn(x) increased owing to the participation of the blended MnO2 during the activation, while the blending of Fe2O3 showed an inhibited effect. AC‐P10 showed the highest NO removal efficiency at 74.2%, which was 32.8%, 27.0% and 24.2% higher than that of AC, AC‐Mn4 and AC‐Fe6. The operating temperature adaptability and stability of catalysis activity of AC‐P10 are good. Manganese is the main catalyst of AC‐P(x), and Fe is an accelerant to stimulate the catalytic activity of Mn. The extremely high NO removal activity of AC‐P(x) was due to the synergistic effect of surface functional groups and metals, but the catalysis of metals played a more important role.CONCLUSIONPyrolusite is suitable to prepare the AC‐based denitrification catalyst (AC‐P(x)) for SCR NO removal because the Mn and Fe contained in the pyrolusite showed a synergistic effect. © 2017 Society of Chemical Industry