3,4-dihydroxybenzoic acid is an organic compound with the molecular formula C7H6O4 and molecular weight 154.12, occurring naturally in rice flue-cured tobacco, Burley tobacco, Oriental flue-cured tobacco and flue gas. 3,4-dihydroxybenzoic acid is a white to light brown needle-like crystal, soluble in hot water, ethanol, ether, slightly soluble in cold water, but insoluble in benzene. Placing 3,4-dihydroxybenzoic acid in boiling water not only causes decomposition, but also releases carbon dioxide.
It is understood that 3,4-dihydroxybenzoic acid is mainly used as dye intermediates, pharmaceutical intermediates and analytical reagents in coating, medicine, chemical industry, biology and other fields. During storage, 3,4-dihydroxybenzoic acid should avoid contact with strong oxidizer and alkali, and should not be mixed with oxidizer and strong acid for storage or transportation. It is recommended that 3,4-dihydroxybenzoic acid be stored in a cool, dry and ventilated special explosive storehouse, which should be far away from fire and heat sources, and be equipped with appropriate leakage containers, explosion-proof lights and ventilation facilities.
