Decolorization of aqueous glyoxal solutions

摘要

An aqueous glyoxal solution is decolorized by a process in which the said solution is passed over granulated active carbon which is arranged in a fixed bed and whose differential pore radius distribution has a maximum of from 10 to 100 A, the Peclet number being from 500 to 5000, the decolorized glyoxal solution is discharged, the active carbon bed is then regenerated by treating it with an aqueous solution of an alkaline agent and then with an aqueous acid, and further glyoxal solution to be decolorized is passed over the active carbon regenerated in this manner.