>[…] Because manufacturers can prepare ethanol from renewable sources, researchers consider the biofuel a good alternative to standard fossil fuels such as gasoline. Indeed, its production and use have increased remarkably in the last ten years; manufacturers now commonly add ethanol to gasoline fuels.

Despite this increased use, however, ethanol has several disadvantages. It has a lower calorific value than standard gasoline (19.6 vs. 32 MJ/liter); moreover, it is corrosive. For this reason, the maximum amount which can be added to standard gasoline is about 10 %; cars cannot use fuels with higher ethanol amounts without engine modifications.

Butanol: a Better Option

1-Butanol (CH3-CH2-CH2-CH2-OH), an alcohol with a longer chain, could be a better alternative to ethanol. Indeed, it has a higher calorific value (29.2 MJ/liter) and it is much less corrosive; because of this, manufacturers can add it to gasoline in higher proportions without engine modifications, and theoretically it could completely replace the gasoline. Moreover, its octane number is very similar to that of gasoline – 96 vs 91-99.

Despite these characteristics, however, we’re not yet using butanol in cars due to the difficulties in producing the alternative biofuel. […]<