1. Tannage,ink making, paper sheet,silk gluing,boiler cleaning media and so on.
2. Dying Intermediary reagent
Properties :straw yellow--light brown powder or loose polish flake or sponginess solid.Turn to black if exposure to air.It's odorless but intense acerbity.Soluble in water, ethanol,acetone,hardly soluble in benzene,chloroform,ether,and petroleum ether.Melting and decompounding on point 210∼215,flash point 187.self-ignite on 526.6 and no toxicity.