Butanol or butyl alcohol can refer to any of the four isomeric alcohols of formula C4H9OH:*n-Butanol, butan-1-ol, 1-butanol, n-butyl alcohol;Isobutanol, 2-methylpropan-1-ol, isobutyl alcohol;sec-Butanol, butan-2-ol, 2-butanol, sec-butyl alcohol;tert-Butanol, 2-methylpropan-2-ol, tert-butyl alcohol. It can also refer to butanol fuel, a proposed alternative to gasoline. n-butanol isobutanol sec-butanol tert-butanol… (More on Butan-1-ol)