PURIFYING PHENOL- AND PHENOL-FORMALDEHYDE

摘要

Phenol or phenol-formaldehyde containing waste water is purified with chlorine dioxide by treating the waste water with alkali or alkaline earth metal chlorite in the presence of formaldehyde and the weight ratio of formaldehyde to phenol is between 0.5 to 2:1 and the mole ratio of the sum of phenol + formaldehyde to chlorite is between 1:1.2 to 1:2, whereupon the treated water is decolorized, in a given case in known manner.