| abstract |
Crude hydroxyphenylalkane, e.g., 1,1,1-tris(4'-hydroxyphenyl)ethane, is purified, to reduce color and prevent caustic solution turbidity, (a) by contacting the hydroxyphenylalkane in alcoholic solution with an alkali metal dithionite, preferably in the presence of an alkalinity agent such as an alkali metal borohydride, more preferably by introducing the dithionite into the alcoholic solution as an alkaline aqueous solution, (b) precipitating the hydroxyphenylalkane from the alcoholic solution, and optionally (c) rinsing the hydroxyphenylalkane with an alkaline aqueous solution of the dithionite. |