Emissions of reactive nitrogen compounds (RNCs) from two vehicles with turbo-charged spark ignition engines over cold start driving cycles

This paper reviews the emissions of reactive nitrogen compounds (RNCs) from modern vehicles fitted with spark ignition en-gines and three-way catalysts. Specific aspects pollutants involved – their formation are discussed. Cold start driving cycles scenarios under which all four RNCs can be significant; mechanisms behind trends ex-plored. Experimental data obtained two tested over different cold presented analysed. The use gravimetric molar metrics explored. Ammonia, a species is currently not regulated for passenger cars in any automotive market, identified as forming majority RNC entire cycle. While ammonia strongly linked to aftertreatment system warmup periods high load, significant were also measured certain hot-running, low load conditions, even at idle. For duration test procedures employed, profile was dominated by ammonia, accounted between 69% 86% ex-haust gas. Emissions compared available legislative precedents (i.e. limits force various jurisdic-tions). Finally, possibilities control exhaust unregulated briefly