| Patent Number |
Title Of Patent |
Date Issued |
| 5808142 |
Process for the preparation of 2-hydroxynaphthalene-6-carboxylic acid |
September 15, 1998 |
| A process for the preparation of 2-hydroxynaphthalene-6-carboxylic acid using potassium carbonate and CO at temperatures above 260.degree. C. and at a pressure of at least 10 bar comprises using 2-hydroxynaphthalene-3-carboxylic acid and/or 2-hydroxynaphthalene-3,6-dicarboxylic acid |
| 5643494 |
Process for the preparation of aromatic hydroxy carboxylic acids |
July 1, 1997 |
| A process for the preparation of aromatic hydroxy carboxylic acids by reacting alkali metal phenolates or alkali metal naphtholates with alkali metal carbonates and carbon monoxide, with subsequent acidification, wherein the solid starting materials--alkali metal carbonate and/or alkali |
| 5543564 |
Process for releasing acidic organic compounds from salts thereof by carbon dioxide |
August 6, 1996 |
| This invention embodies a process for releasing acidic organic compounds in high yield and good purity from aqueous solutions of their salts which comprises converting the salts by carbon dioxide to their corresponding free acidic organic compounds and metal hydrogen carbonates, removing |
| 5532406 |
Process for preparing aromatic hydroxycarboxylic acids |
July 2, 1996 |
| A process for preparing aromatic hydroxycarboxylic acids or di-salts thereof by reaction of alkali metal phenolates or naphtholates with carbon dioxide, in the presence or absence of a further alkali metal salt, which comprises introducing the solid phenolate or naphtholate starting |
