The development of the new NO_x reduction catalyst with hydrocarbons and the cleanup system of exhaust gases for lean-burn gasw engines

摘要

The emissions of NO_x,HC,and CO contained in the exhaust gases from lean-brun natural-gas-fueled engines can be removed by using a catelyst system.This pape rdescribes hte development of the new de -NO_x catalyst and of hte total cleanup system for lean-burn gas engines without the addition of reducing agents.The NO_x was effectively reduced by the unburned nonmethane hydrocarbons (NMHC) over the alumina supported silver (Ag/Al_2O_3) catalyst at 723-823 K.the activity and lifetime of the Ag/Al_2O_3 catalyst was demonstrated using the exhaust gas from a 400 kW class leanburn gas engine for more than 2000 h.The addition of an oxidation catalyst to the downstream of the Ag/Al_2O_3 catalyst is effective in removing the NMHC and CO in the exhaust gas.