Research advance in mechanism of low-temperature SCR of NO on carbon materials

The behavior of the reactant molecules on carbon materials surface，formation of adsorbed NO₂ ，dimer (NO)₂，—NO₂ or pyridine compounds from single component NO is reviewed. When NO and O₂  coexists，NO is oxidized to NO₂ by the adsorbed O₂. When NO，O₂ and NH₃ coexists，the reaction occurs between adsorbed NH₃ and adsorbed NO₂. The mechanism of selective catalytic reduction（SCR）of NO on activated carbon fibers（ACF）catalyst is presented as follows. At a low temperature NH₃-SCR follows the Langmuir-Hinshelwood mechanism. While at a high temperature NH₃-SCR follows the Eley-Rideal mechanism. The catalyst pore structure characteristics and surface chemical functional groups are the main factors of the low temperature SCR of NO.