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Efficient hydrocarbon (HC) trap materials have been developed to trap the major emitting HC compounds from gasoline direct injection engines. Online FTIR measurements on different test cycles and catalytic systems showed that AHC, C5 compounds, and CH4 were the most emitted species at cold-start phase (up to 100 sec). Making AHC and C5 as targets for improving the HC light-off, lab scale reactor set-up was established with toluene and iso-pentane feed pumping system along with propane-propene mixture. TGA screening experiments conducted with ex-situ toluene adsorption and the results revealed that BEA type materials have moderate to higher HC trapping temperature and HC storage capacity. In the present investigation, BEA-HS exhibited outstanding stability and trapping ability even after 850 °C hydrothermal aging. PGM and TM based BEA materials were evaluated for HC-TPD experiments with TWC gas composition.

HC-SCR is more convenient when compared to urea-SCR, since for HC-SCR, diesel fuel can be used as the reductant which is already available onboard the vehicle. However, the DeNOX efficiency for HC-SCR is lower than that of urea-SCR in both low and high temperature windows. In an attempt to improve the DeNOX efficiency of HC-SCR, the effect of hydrogen were evaluated for the fresh and aged catalyst over 2 wt.% Ag/Al₂O₃ using a Euro-4 diesel engine. In this engine bench test, diesel fuel as the reductant was injected directly into the exhaust gas stream and the hydrogen was supplied from a hydrogen bomb. The engine was operated at 2,500 rpm and BMEP 4 bar. The engine-out NOX was around 180 ppm-200 ppm. H₂/NOX and HC₁/NOX ratios were 5, 10, 20, and 3, 6, 9, respectively. The HC-SCR inlet exhaust gas temperatures were around 215°C, 245°C, and 275°C. The catalyst volumes used in this test were 2.5L and 5L for both fresh and aged catalysts.

Compressed natural gas (CNG) has been regarded as an alternative fuel for current fossil fuels such as gasoline and diesel. Recently the increasing interest in shale gas is drawing more attention to CNG vehicles of which number is expected to increase. Exhaust gas from CNG engines with lean combustion contains relatively low nitrogen oxides and particulate matters compared to conventional fossil fuel based engines. However, high amount of unburned methane, which has much higher greenhouse warming potential than CO2, limits the wide use of CNG for many applications. Even though Pd-based catalysts have been popularly studied in order to convert methane, their activity and durability have not been sufficient for practical applications to aftertreatment of lean burn CNG engines and the formation of a new Pd containing.