B 4.4. Does the addition of ethanol to gasoline cause volatile compound emissions?
Even though ethanol is a low-volatility fuel, five times less volatile than gasoline, it has the effect of increasing volatility in the blend with gasoline. The magnitude of the increase in such emission basically depends on the ethanol content of the blend and the gasoline composition. This characteristic, which can actually be positive in temperate zones because it makes cold starts easier, has been the subject of a lot of discussion due to the allegation that favors the permeability of the fuel into components made from some types of rubber and plastic, resulting in increased volatile compound emissions. It is important to note that this effect can be minimized by adjusting the gasoline composition for the intended ethanol content of the blend. Because there is a tendency to examine the increased volatility of the blend separately, which often results in exaggerations of the magnitude of its impact, it is advisable to conduct the analysis within the context of the total pollutant em
