CH3CH2CH2CH2OH

CH3CH2CH2CH2OH is the chemical formula for 1-butanol, also known as n-butanol or butyl alcohol. It is an aliphatic primary alcohol with four carbon atoms. Its IUPAC name is butan-1-ol and its molecular formula is C4H10O (molar mass 74.12 g/mol).

At room temperature it is a colorless, flammable liquid. It has a boiling point of about 117.7°C and a melting point near −89°C. The density is around 0.81 g/mL at 20°C. It has limited water solubility, approximately 7.5 g per 100 g of water at 25°C, and is miscible with many organic solvents.

Industrial production of 1-butanol is mainly by the oxo (hydroformylation) process, in which propylene is converted to butyraldehyde and subsequently hydrogenated to yield 1-butanol. It can also be produced biologically via acetone–butanol–ethanol (ABE) fermentation, typically as part of a mixture of solvents. Major applications include use as a solvent in coatings, inks, cleaners, and cosmetics, as well as a chemical intermediate for the production of plasticizers (such as butyl esters) and other butyl-derived chemicals.

Safety and environmental aspects: 1-butanol is a flammable liquid and its vapors can form explosive mixtures with air. It can irritate skin, eyes, and the respiratory tract. It is readily biodegradable and has relatively low aquatic toxicity, but spills and high-concentration exposure should be managed to minimize hazards.