Process for the preparation of tannin insoluvel, process for treatment of waste insoluvel using tannin and tannin adsorcao process that uses

摘要

There is disclosed an insoluble tannin preparation process, in which a tannin is first dissolved in an aldehyde aqueous solution. Then, ammonia is added to the solution to produce a precipitate, and the resulting precipitate is subjected to aging. The insoluble tannin thus prepared is employed to treat a waste liquid. Furthermore, there is disclosed an adsorption process in which a tannin is first dissolved in a solution containing a material to be adsorbed. Thereafter, an aldehyde is added to the solution to produce a precipitate having tannin as a principal constituent. The material to be adsorbed is adsorbed to this precipitate.