THE NEW “ENHANCED NH3-SCR” REACTION FOR NOx EMISSION CONTROL
نویسندگان
چکیده
NH3-Selective Catalytic Reduction (SCR) is applied worldwide to DeNOx of combustion exhausts from stationary and mobile sources, but a greater DeNOx activity at low temperatures is desired to meet forthcoming restrictive legislations. We have obtained high NO reduction efficiencies at 200 – 300 °C over commercial V-based and Fe-exchanged zeolite catalysts by reacting NO with both ammonia and nitrates (e.g. ammonium nitrate) according to a novel “Enhanced SCR” reaction, 2 NH3 + 2 NO + NH4NO3 → 3 N2 + 5 H2O. This opens new pathways for low-T NOx reduction wherein the DeNOx activity is optimized by dosing an aqueous solution of nitrates to the SCR reactor feed stream.
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