Benzoic Acid And Its Uses
Benzoic acid is colorless and odorless flaky crystal. It sublimates rapidly at 100℃, and its vapor is very irritating and easy to cause coughing after inhalation. It is slightly soluble in water, easily soluble in organic solvents such as ethanol, ether, chloroform, benzene, toluene, carbon disulfide, carbon tetrachloride and turpentine. Benzoic acid is widely present in nature in the form of free acids, esters or derivatives. Benzoic acid has the effect of inhibiting the growth of fungi, bacteria, mold, generally used as a preservative of drugs or food, and also used in the performance improvement of alkyd resin coating, production of plasticizer and flavor, as a pharmaceutical and dye intermediates and anti-rust agent of steel equipment. For medicinal use, it is usually applied to the skin to treat ringworm skin diseases. Benzoic acid and its sodium salt, sodium benzoate, are very commonly used as food preservatives. Under acidic conditions, it has an inhibitory effect on yeasts and molds. When the pH value is 3, the antibacterial power is strong, and when the pH value is 6, it has a very poor effect on many molds, so the optimal pH value for bacteriostasis is 2.5-4.0.
