ethanol

Ethanol, also known as ethyl alcohol, is a simple organic chemical with the formula C2H5OH. It is a colorless, volatile, flammable liquid that is miscible with water and many organic solvents. In pure form it has a characteristic sweet odor.

Ethanol is produced biologically by fermentation of sugars by yeast. Common feedstocks include sugarcane, corn, wheat, and other cereals. Industrially, ethanol can also be produced by the catalytic hydration of ethene, a petrochemical route that does not rely on biomass.

Major uses include consumption as a beverage, as a fuel or fuel additive (for example gasoline blends such as E10 and E85), as a solvent in laboratory and industrial settings, and as a chemical feedstock for products such as ethyl esters and acetic acid.

Health and safety: In the body, ethanol is metabolized in the liver by alcohol dehydrogenase to acetaldehyde and then to acetate. It acts as a central nervous system depressant. Moderate consumption affects mood and coordination; high doses can be toxic or fatal. It is a highly flammable liquid that requires proper storage.

Environmental and economic aspects: Ethanol produced from biomass can reduce net greenhouse gas emissions compared with fossil fuels, depending on feedstock and production methods. Large-scale use raises concerns about land use, food prices, water use, and the sustainability of farming practices.

History: Ethanol has been produced by fermentation for thousands of years. In the 19th century Louis Pasteur helped establish yeast as the agent of fermentation, which enabled early industrial production and quality control.