NOx Aromatics Effects in Catalyst-Equipped Gasoline Vehicles 941869
Investigations into fuel compositional effects on emissions using model and full range fuels suggest aromatic components promote NOx conversion over the catalyst
Steady state results derived from a single engine (Ricardo Gasoline Fuels Consortium data) show that at a typical part load condition, the catalyst removes NOx less effectively with lower aromatic fuels. Neither CO nor H2 contribute significantly to catalyst performance.
Two vehicles were tested over a European cycle. Toluene formed more combustion chamber NOx, offset by increased catalyst conversion efficiency giving lower tailpipe NOx than isooctane in the vehicle with the better catalyst light-off and AFR control.