To provide a method for purifying a polyol by which a polyamine can be readily and efficiently removed to provide the polyol having good quality by adding an organic dicarboxylic acid to the polyol containing the polyamine, and removing the obtained precipitate.
(B) An organic dicarboxylic acid or an anhydride thereof is added to (A) a polyol containing a polyamine, and the resultant precipitate is removed to purify the polyol. The component A is preferably a decomposed and recovered polyol obtained by decomposing a polyurethane resin, and the polyol is preferably a polyether polyol. Preferably, the component B is oxalic acid and the amount to be added is regulated so that the carboxy group may be 0.3-1.05 equivalent per equivalent of the amino group of the polyamine. The component B is applied to a decomposition and recovery step in the decomposition and recovery method of the polyurethane resin.
MURAYAMA KOICHI
KUMAKI TAKASHI
| JPS5586814A | 1980-07-01 | |||
| JPS57159817A | 1982-10-02 | |||
| JPH0717922A | 1995-01-20 | |||
| JPH0881423A | 1996-03-26 | |||
| JPH1135546A | 1999-02-09 | |||
| JPS5152478A | 1976-05-10 | |||
| JPH09132670A | 1997-05-20 | |||
| JPS5780438A | 1982-05-20 |
| WO1997027243A1 | 1997-07-31 |
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