In Situ Hydrogen Uptake and NO(x) Adsorption on Bifunctional Heterogeneous Pd/Mn/Ni for a Low Energy Path toward Selective Catalytic Reduction

[Image: see text] Facilitating catalyst accessibility of H(2) and NO(x) at the catalyst surface remains a great challenge in catalytic selective catalytic reduction (SCR). The efficient conversion of NO(x) into N(2) under mild conditions is an attractive pathway as SCR usually requires high operating temperature which consumes extra operating energy and restricts the possible locations of an SCR device. The H(2) supply concentration of conventional H(2)-SCR is relatively sparse (0.5–2%), which leads to a relatively high operating temperature to activate H. We developed a H(2)-SCR process with the monolithic catalyst which combined with localized rarefied hydrogen enrichment enhanced by porous nickel and adsorption of NO(x) on Mn oxide with only 0.08, 0.25, and 0.42% palladium can achieve over 80% NO removal efficiency at 120, 100, and 90 °C. Maximizing the role of nickel foam-fixed hydrogen and Mn oxide in combination with NO can provide enriched NO(x) and H(2) atmosphere for adjustable valence state Pd to yield positive catalytic behavior.