Tetrahydrofuran, abbreviated as THF, is a heterocyclic organic compound. It belongs to the ether class and is the complete hydrogenation product of the aromatic compound furan. Tetrahydrofuran is one of the strongest polar ethers. It is used as a medium-polar solvent in chemical reactions and extractions. It is a colorless, volatile liquid at room temperature with an ether-like smell. It is soluble in most organic solvents such as water, ethanol, ether, acetone, and chemicalbook benzene, and is called a “universal solvent.” It is partially miscible with water at room temperature, and some illegal reagent dealers use this to make huge profits by adding water to tetrahydrofuran reagents. Since THF has a tendency to form peroxides during storage, industrial products generally add the antioxidant BHT. The moisture content is ≦0.2%. It has the characteristics of low toxicity, low boiling point, and good fluidity.