Emissions of Organic Species from a Nonroad Vanadium-Based SCR Aftertreatment System 2015-01-2904
U.S. and European nonroad diesel emissions regulations have led to the implementation of various exhaust aftertreatment solutions. One approved configuration, a vanadium-based selective catalytic reduction catalyst followed by an ammonia oxidation catalyst (V-SCR + AMOX), does not require the use of a diesel oxidation catalyst (DOC) or diesel particulate filter (DPF). While certification testing has shown the V-SCR + AMOX system to be capable of meeting the nitrogen oxides, carbon monoxide, and particulate matter requirements, open questions remain regarding the efficacy of this aftertreatment for volatile and nonvolatile organic emissions removal, especially since the removal of this class of compounds is generally attributed to both the DOC and DPF. This article discusses the emissions of n-alkanes, branched alkanes, saturated cycloalkanes, carboxylic acid derivatives, aromatics, aldehydes, polycyclic aromatic hydrocarbons and their derivatives, hopanes and steranes, and soluble organic and organic carbon fractions of particulate matter. Large reductions of all species are found, with the exception of carboxylic acid derivatives. These results are discussed in the context of the relevant catalyst components and their previously published attributes.