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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.

The conventional evaluation of automotive catalysts has been carried out based on end-pipe measurement whereby the gas at the tailpipe of an automobile or the outlet of the bench reactor is monitored by using various analytical techniques such as Fourier-transform infrared spectroscopy (FTIR), mass spectrometry (MS), and gas chromatography (GC). However, this approach only provides overall gas concentrations at the exit flow of a monolith catalyst. Thereby, there is a deficiency of information on intra-catalyst chemistry. To obtain deeper insights on the design of an automotive catalyst, an emission breakdown analysis is critical. In this way, a comprehensive understanding of continuous processes along the catalyst length can be achieved. Here, we introduce the High Throughput Vehicle Test (HTVT), which is an analysis technology method for simultaneous emission observations at different catalyst positions in the vehicle.

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.

The Urea-SCR system has been widely used for the after-treatment of NOx to meet tighter regulations for the heavy-duty diesel engine. In addition, the long useful life time of heavy duty engines requires the highly durable components of urea-SCR system such as the catalyst and urea-dosing unit. This paper focused on the deactivation of the SCR catalyst for the EURO4 engine. The NOx conversion of field-aged catalysts was monitored with certain mileage accumulation at the engine bench and laboratory reactors. The postmortem analysis of the catalysts has been carried out to investigate the possible deactivation routes of SCR catalysts in the real driving condition. The analysis showed that the SCR catalyst was durable enough to meet the legislations over the useful lifetime of the engine and found that the non-thermal mechanisms such as poisoning were major routes for the deactivation of catalysts while the thermal sintering was shown to be marginal.

Urea-SCR systems have become one effective method for meeting the ever tightening NOx emission control regulations for diesel engines. Higher activity of SCR catalysts in the low temperature region is crucial for meeting emission regulations and improving fuel economy. Some of the new catalytic components in the literature have shown good low temperature SCR activity, but they have not been fully confirmed to be durable enough for mobile applications. Fe-zeolite has been widely used in mobile applications due to its wide operating temperature window, but after exposure to large amounts of HCs at low temperatures, it is easily deactivated. We developed new SCR catalysts with improved low temperature activity and improved durability against HC fouling and thermal sintering by combining OSC (oxygen storage component) with Fe-zeolite.

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.

H2S, which causes the rotten egg odor, has been the one of gaseous components in interest and suppressed by the use of NiO as a scavenger since the start of automotive catalysts application to gasoline emission control in 1970s. Ni-free H2S suppression has been one of topics in gasoline emission control, because the controversial NiO is not permitted in some regions. It was found that some zeolites had unique H2S trapping capability from the powder screening works for the alternative H2S scavenger to NiO. By combining the well-known property of HC-trapping ability of zeolites, zeolite-containing three-way catalysts were developed to suppress H2S as well as cold-start HC emission for gasoline engine powered vehicle. The newly developed catalyst showed equivalent H2S suppression ability to the conventional NiO-containing catalyst at engine and vehicle test cycles that consisted of sulfur storage and release steps.