Search Results

NOx emitted from diesel is one of the main air pollutants for most countries. To reduce the emission of NOx could promote to diffuse diesel vehicles. A NOx storage/reduction (NSR) catalyst has been developed for the diesels. The catalyst for NSR is strongly poisoned by sulfur. We have found good reaction of CaCO3 with sulfur dioxide by using a thermogravimetry. We obtained desulfurization breakthrough characteristic for the sample of the CaCO3 which is washcoated on the monolith. As a result, this sample which has specific surface area, of 100 m2/g, absorbed SO2 about 0.43 ~ 0.45 g−SO2/g−CaCO3. In this experimental condition, The conversion of the sulfate does not depend on the amount of the supported CaCO3. The absorption efficiency of these samples were more than 99.4%. According to this result, it was found that the necessary amount of the absorbent was supposed to be 0.538 kg or 2.1 L for 100,000 km running.

A canister filled with activated carbon prevents the emission of hydrocarbon into the air, through repeated adsorption and desorption process. A small amount of hydrocarbon, with n-butane as one of the major components, remains inside the canister. The diffusion of this residual n-butane affects Diurnal Breathing Loss performance. This study reports the quantitative difference of n-butane diffusion and breakthrough under three experimental conditions. Furthermore, diffusion speed, which is an important factor in the analysis of canister performance and the design development of canister, was also calculated.