Separating 4, 4'-benzophenone dicarboxylic acid from a mixture of 4, 4'-and 2, 4'-benzophenone dicarboxylic acids and concurrently producing 2 anthraquinone carboxylic acid

Claim 1

A PROCESS FOR SEPARATING 4,4''-BENZOPHENONE DICARBOXYLIC ACID FROM A MIXTURE OF 4,4''- AND 2,4''-BENZOPHENONE DICARBOXYLIC ACIDS AND CONCURRENTLY PRODUCING 2-ANTHRAQUINONE CARBOXYLIC ACID WHICH COMPRISES HEATING SUCH MIXTURE OF BENZOPHENONE DICARBOXYLIC ACIDS IN THE PRESENCE OF SULFURIC ACID TO CONVERT 2,4''-BENZOPHENONE DICARBOXYLIC ACID TO 2-ANTHROQUINONE CARBOXYLIC ACID, TREATING THE RESULTING MIXTURE WITH WATER TO PRECIPITATE A MIXTURE OF 4,4''-BENZOPHENONE DICARBOXYLIC ACID AND 2ANTHRAQUINONE CARBOXYLIC ACID, SEPARATING SAID MIXTURE FROM THE RESULTING AQUEOUS SOLUTION OF SULFURIC ACID, REACTING THE SULFURIC ACID FREE MIXTURE OF 4,4''-BENZOPHENONE DICARBOXYLIC ACID AND 2-ANTHRAQUINONE CARBOXYLIC ACID WITH AN AQUEOUS SOLUTION OF SODIUM HYDROXIDE CONTAINING SODIUM HYDROXIDE IN AN AMOUNT WHICH IS A 10 PERCENT EXCESS OVER THAT REQUIRED TO EACT WITH THE CABOXY GROUPS AND AN AMOUNT OF WATER SUFFICIENT TO DISSOLVE THE 4,4''BENZOPHENONE DICARBOXYLATE LEAVING SODIUM 2-ANTHRAQUINONE CARBOXYLATE AS A SOLID, SEPARATING SAID SOLUTION FROM SAID SOLID, AND SEPARATELY RECONSTITUTING 2-ANTHRAQUINONE CARBOXYLIC ACID AND 4,4''-BENZOPHENONE DICARBOXYLIC ACID.