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Acidified 2,4-dinitrophenylhydrazine (DNPH) solution, or DNPH-impregnated cartridges are commonly used for the collection of automotive exhaust carbonyl compounds. There are some DNPH-carbonyl compounds in not in use DNPH cartridges and DNPH solution. Furthermore, concentrations of automotive exhaust carbonyl compounds are decreasing according to improvement of the purification technology for automotive exhaust. Automotive exhaust carbonyl compounds become to be difficult to be analyzed with DNPH collection method, because of these two reasons. It is thought that reliable analysis of acrolein in automotive exhaust is very difficult because concentration of DNPH-acrolein in extracted solution is not stable. Furthermore, it is found out that DNPH-acrolein in DNPH-cartridge is disappeared for short time storage in this research.

Numerous studies have been conducted on the effect of gasoline composition on automobile exhaust hydrocarbons, in order to improve the air quality and reduce the impact on the environment. However, the quantitative relationship between gasoline composition and exhaust hydrocarbon has not been clarified. The purpose of this study is to evaluate the characteristics of individual hydrocarbons in gasoline and to clarify the effect of the gasoline composition on engine-out exhaust hydrocarbons. Experiments were performed on a single cylinder research engine operating under steady state condition. The test fuels were blended gasolines of alkylate, catalytic reformate and fluid catalytic cracking gasoline. Chemically defined binary fuel mixtures of isooctane, benzene, toluene, xylene and ethylbenzene were used as variables to study their impact on exhaust hydrocarbons. The individual exhaust hydrocarbon species were analyzed using a gas chromatograph with flame ionization detector (FID).

Gas collection techniques for determining hydrocarbons (HCs) in automotive exhaust are discussed. Stability of HCs in a Tedlar bag (3L) is cleared on this study. C7-C12 alkanes storaged in the Tedlar bag were lower than correct value by adsorption on bag surface. HCs storaged in the Tedlar bag were higher than correct value by condensation of water vapor immediately after sampling. Sampling techniques of vehicle exhaust gases that can be getting reliability must satisfy a number of requirements. It needs to retain the components in exhaust gases for several hours, without photo chemical reactions, and to collected it at a constant speed. Sampling method, therefore, both with a heated stainless steel canister and with a sampling method with a heated stainless steel syringe were developed to satisfy these requirements.