| 摘要 |
<p>PURPOSE: A manufacturing method of 6-hydroxy-2-naphthoic acid is provided to improve the yield and selectivity of 6-hydroxy-2-naphthoic acid and reduce production cost by a simple process. CONSTITUTION: A manufacturing method of 6-hydroxy-2-naphthoic acid comprises; (i) a step which manufactures a 2-naphthol alkali metal solution by reacting 2-naphthol with alkali metal hydroxide in water; (ii) a step in which manufactures 2-naphthol alkali metal 2-naphthol alkali metal in a solid state by drying the 2-naphthol alkali metal solution at pressure of less than 0.1 atm; (iii) a step of which manufactures alkali metal salt of 6 hydroxy-2-naphthoic acid by reacting the 2-naphthol alkali metal with carbon dioxide; and a step (iv) which manufacturing 6-hydroxy-2-naphthoic acid by treating alkali metal salt of 6 hydroxy-2-naphthoic acid with acid. [Reference numerals] (A1) Manufacturing 2-naphthol alkali metal solution by reacting 2-naphthol with alkali metal hydroxide in water; (A2) Step (a); (B1) Manufacturing 2-naphthol alkali metal 2-naphthol alkali metal in a solid state by drying the 2-naphthol alkali metal solution at pressure of less than 0.1 atm; (B2) Step (b); (C1) Manufacturing alkali metal salt of 6 hydroxy-2-naphthoic acid by reacting the 2-naphthol alkali metal with carbon dioxide; (C2) Step (c); (D1) Manufacturing 6-hydroxy-2-naphthoic acid by treating alkali metal salt of 6 hydroxy-2-naphthoic acid with acid; (D2) Step (d)</p> |
