Highly-basic large-pore zeolite catalysts for NOx reduction at low temperatures

A method for reducing NOx in an oxygen-rich diesel engine exhaust, said method comprising:

• injecting a diesel fuel into said diesel engine exhaust to produce a mixture containing said diesel engine exhaust and said diesel fuel, said diesel fuel in a concentration above 500 ppm C1;
• and
• contacting a selective catalytic reduction (SCR) catalyst comprising a large-pore, basic zeolite with said mixture at a temperature less than about 250 degrees C. to reduce said NOx contained in said diesel engine exhaust, wherein at least a portion of said NOx is converted to NO2 in the presence of a non-thermal.

A method for reducing nitrogen oxides (NOx) in oxygen-rich exhausts from combustion, the method comprising the steps of:

• intermittently adding diesel fuel which has a boiling point in the range from about 150 degrees C. to about 450 degrees C. to an engine exhaust comprising NOx to produce a diesel fuel-containing engine exhaust;
• and
• converting NOx in the engine exhaust in the absence of added diesel fuel at a temperature less than about 250 degrees C., with a selective catalytic reduction (SCR) catalyst comprising an alkali metal cation exchanged faujasite-type zeolite, to a gas flow including N2, CO2 and H2O.