Abstract

Ethanol's unique combination of physical and chemical properties has led to its use as a solvent, a germicide, a beverage, an antifreeze, a fuel, a depressant, and a chemical intermediate for other organic chemicals. Ethanol from fermentation processes is the most important source. Most industrial ethanol is produced from ethylene by the direct hydration process. The subsidized (federal and state) use of fermentation ethanol in gasoline has fueled a rapid growth in U.S. production, which has provided some ethanol for crossover to the industrial market. The 1990 Clean Air Act requiring the use of oxygenates in gasoline has further fueled this growth. Corn is the principal feedstock for fermentation in the United States, and sugar cane is the most important raw material outside the United States. This rapid growth has also caused a renewed interest in research into this ancient process. The main uses for industrial ethanol are as an intermediate for the production of other chemicals and as a solvent. The United States Treasury, Bureau of Alcohol, Tobacco, and Firearms oversees the production, procurement, and use of ethanol in the United States.