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

Facilitating catalyst accessibility of H and NO at the catalyst surface remains a great challenge in catalytic selective catalytic reduction (SCR). The efficient conversion of NO into N 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 supply concentration of conventional H-SCR is relatively sparse (0.5-2%), which leads to a relatively high operating temperature to activate H. We developed a H-SCR process with the monolithic catalyst which combined with localized rarefied hydrogen enrichment enhanced by porous nickel and adsorption of NO 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 and H atmosphere for adjustable valence state Pd to yield positive catalytic behavior.