Reactions Taking Place in Automobile Emissions, and Smog Formation

Reactions Taking Place in Automobile Emissions, and Smog Formation 

During the combustion process in gasoline engines, benzene, toluene, acetylene, acrolein, and aromatic aldehydes [94], of which the latter have a particularly high photochemical activity, are formed from volatile aromatics by cracking and disproportionation, and also by oxidation. 

Methyl nitrate, acrolein, aceton, and other products are formed as a result of ring cleavage in the presence of nitric oxides [95]. When automobile exhaust gases are exposed to ultraviolet light in the presence of nitric oxides, 30% of the benzene, 68% of the toluene, and 84% of the xylene decompose within six hours [96]. 

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