Acetic acid: its physical and chemical properties are colorless and transparent liquid, with strong pungent odor, solid at room temperature, easily soluble in water and alcohol, and its relative density (D4) is 1.0492. The melting point is 16℃, the boiling point is 118℃, the refractive index (nd20) is 1.3716, the flash point is 39℃, the lower explosion limit of steam-air mixture is 4% ~ 17% (vol), and the self-ignition point is 427℃. It is miscible with water, ethanol, benzene and ether, but insoluble in carbon disulfide. Low concentration acetic acid is non-toxic, but when its concentration in aqueous solution or solvent exceeds 50%, it has strong corrosiveness to skin, strong irritation to eyes, respiratory tract, esophagus and stomach, and can cause vomiting, diarrhea, nerve paralysis, urinary poisoning and even death.
Main uses of acetic acid:
■ Acetic acid → vinyl acetate → polyvinyl acetate → polyvinyl alcohol
■ Acetic acid → vinyl acetate copolymer
■ Acetic acid → acetic anhydride → cellulose acetate
■ Acetic acid→ acetate (ethyl acetate, butyl acetate)
■ Acetic acid → chloroacetic acid
■ Acetic acid→ terephthalic acid (acetic acid as solvent)
It can be further processed into pesticides, medicines, dyes, coatings, synthetic fibers, plastics, adhesives and other products. Therefore, acetic acid is widely used in chemical industry, synthetic fiber, medicine, light industry and other industrial sectors. The main consumption areas of acetic acid are vinyl acetate, PTA, acetic anhydride and acetate.