Decolorization of aqueous glyoxal solutions
AssigneeBASF SE
InventorsGuenther Mueller, Rolf Ramsteiner, Fritz Graf, Leopold Hupfer
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Abstract
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.
Claims14
A process for decolorizing an aqueous glyoxal solution which process comprises:
- passing said solution over a granulated active carbon which is arranged in a fixed bed and which has a maximum differential pore radius distribution of from 10 to 100 A, the Peclet number being from 500 to 5000,
- discharging the decolorized glyoxal solution from said bed,
- then regenerating the active carbon bed at a temperature up to 90.degree. C. by first treating it with an aqueous solution of an alkaline agent and then with an aqueous acid, and
- again passing further glyoxal solution to be decolorized over the active carbon bed regenerated in this manner.
Dependencies are inferred from the claim text.