| 摘要 |
<p>Disclosed is a process for disproportionation of potassium naphthoate to the dipotassium salt of 2,6-NDA which gives reproducible improved yields of up to 40 % which comprises: (a) reacting naphthoic acid in the presence of excess base to produce a disproportionation feed comprising a finely dispersed disordered salt mixture of excess base salts and naphthoic acid salts, wherein the feed is prepared by the steps of: (1) Reacting naphthoic acid in the presence of excess base selected from the group consisting of carbonates and bicarbonates to form a salt; (2) Drying said salt mixture by a method which forms a highly mixed disordered salt mixture characterized by a differential scanning calorimeter (DSC) signature characterized by low melting peaks not previously observed in the salt; and (b) disproportionating said solid salts in the presence of a disproportionation catalyst to form the dipotassium salts of 2,6-NDA.</p> |
