Tannic acid Usage and synthesis

Properties:

This product is a light yellow to light brown powder with a special odor and a very astringent taste; it is soluble in 1 part of water or ethanol, soluble in acetone, and insoluble in chloroform or ether.

Uses:

Clarifier, astringent, crude oil deodorant, fragrance aid; Tannic acid can be used for tanning, ink manufacturing, paper and silk gluing, boiler descaling, etc. It can also be used as a mordant, a clarifying agent for beer and wine, a coagulant for rubber, etc. It can be used in printing and dyeing, metallurgy, chemical book, medicine and other industries. Tannic acid itself has very low toxicity. Precipitation and weight determination of beryllium, aluminum, gallium, indium, niobium, tantalum and zirconium. Ratio determination of copper, iron, vanadium, cerium and cobalt. Precipitant for proteins and alkaloids. External indicator for ammonium molybdate titration of lead. Mordant for dyes.

Production method:

Tannin exists in the bark and fruit of many trees (such as oak and sumac), and is also the main component of the galls formed by insects in these trees, with a content of 50-70%. Crush the gallnuts, remove impurities such as insect corpses and insect excrement, put them into a Chemicalbook copper or wooden extraction tank, extract with soft water, concentrate the extract under reduced pressure, add a small amount of ether, and spray dry to obtain light tannic acid. Medicinal tannic acid is obtained by extracting the concentrate with ether, bleaching the leaching solution with sodium bisulfite, and recovering the ether to obtain medical tannin.

The gallnut is crushed and screened, then soaked with water, the soaking water is clarified, preheated, spray-dried, and the dry powder is sieved to obtain the finished product.