Despite improvements in fuels, engines and catalytic converters, volatile organic compound (VOC) emissions from motor vehicles remain a significant source of pollution in urban areas. Under appropriate conditions, this can result in the formation of photochemical smog. Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) offers a unique ability to study motor vehicle emissions, because it can analyze individual VOCs and inorganic gases in real-time, independent of sample humidity.
The Figure below shows the results of real-time analysis of the exhaust gases of two vehicles: Car B with a catalytic converter fitted, and Car A without. This data was obtained for cars from a near-cold start, the engines at low revolutions and without load for the duration of the analysis. The data reveals very different VOC profiles — both in terms of relative and absolute abundances, and in terms of temporal changes in the data.
Syft Technologies’ has recently introduced a breakthrough in SIFT-MS by adding four negatively charged reagent ions: O–, O2–, OH–, and NO2– to the traditional positive reagent ions H3O+, NO+, and O2+. The high selectivity of SIFT-MS arises from the different reaction mechanisms provided by each of the reagent ions. The unprecedented advance from three to seven reagent ions enables SIFT-MS to provide even greater selectivity and analyze new compounds. Compounds such as CO2, N2O, and SO2 can now be analyzed alongside VOC’s to provide a complete picture of vehicle emissions.
The real-time, broad-spectrum, humidity-independent analysis provided by SIFT-MS makes it ideally suited to direct analysis of VOCs in motor vehicle tail-pipe emissions. Syft’s Voice200ultra solution provides a robust, easy to operate package for sensitive, quantitative analysis for analyte concentrations ranging from part-per-million to part-per-trillion levels.