| 摘要 |
THE INVENTION PROVIDES A METHOD FOR PRODUCING ISOPHTHALIC ACID, CHARACTERIZED BY INCLUDING SUBJECTING A M-PHENYLENE COMPOUND TO LIQUID-PHASE OXIDATION REACTION BY USE OF A MOLECULAR-OXYGEN-CONTAINING GAS IN THE PRESENCE OF A CATALYST AT LEAST CONTAINING A HEAVY METAL COMPOUND AND A BROMINE COMPOUND, AND HYDROUS ACETIC ACID HAVING A WATER CONTENT OF 1 TO 15 MASS%, TO THEREBY YIELD A SLURRY; REGULATING THE TEMPERATURE OF THE SLURRY TO 35 TO 140°C, TO THEREBY CAUSE ISOPHTHALIC ACID TO PRECIPITATE; REMOVING THE ISOPHTHALIC ACID THROUGH TO SOLID-LIQUID SEPARATION TO THEREBY RECOVER A MOTHER LIQUOR; AND RECOVERING THE CATALYST FROM THE MOTHER LIQUOR THROUGH A SERIES OF THE FOLLOWING STEPS (1) TO (4) FOR REUSING AT LEAST A PORTION OF THE CATALYST IN THE LIQUID-PHASE OXIDATION REACTION: (1) AN ADSORPTION STEP INCLUDING REGULATING THE RATIO "AMOUNT BY MOLE OF BROMIDE IONS IN THE MOTHER LIQUOR/TOTAL AMOUNT BY MOLE OF HEAVY METAL IONS IN THE MOTHER LIQUOR" TO 0.3 TO 3, AND THEN EXPOSING THE MOTHER LIQUOR TO A PYRIDINE-RING-CONTAINING CHELATE RESIN WHICH HAS BEEN HEATED TO 35 TO 140°C, SO THAT THE RESIN ADSORBS CATALYST-DERIVED HEAVY METAL IONS AND BROMIDE IONS, AND ALSO ADSORBS A CARBOXYLIC ACID MIXTURE WHICH HAS BEEN BY-PRODUCED THROUGH THE LIQUID-PHASE OXIDATION REACTION, (2) AN ELUTION STEP (A) OF EXPOSING HYDROUS ACETIC ACID HAVING A WATER CONTENT OF 1 TO 15 MASS% TO THE PYRIDINE-RING-CONTAINING CHELATE RESIN WHICH HAS UNDERGONE THE ADSORPTION STEP, THEREBY YIELDING AN ELUATE CONTAINING THE BY-PRODUCED CARBOXYLIC ACID MIXTURE, (3) AN ELUTION STEP (B) OF EXPOSING WATER OR HYDROUS ACETIC ACID HAVING A WATER CONTENT OF 20 MASS% OR MORE TO THE PYRIDINE-RING-CONTAINING CHELATE RESIN WHICH HAS UNDERGONE THE ELUTION STEP (A), THEREBY YIELDING AN ELUATE CONTAINING CATALYST-DERIVED HEAVY METAL IONS AND BROMIDE IONS, AND (4) A DISPLACEMENT STEP OF EXPOSING HYDROUS ACETIC ACID HAVING A WATER CONTENT OF 1 TO 15 MASS% TO THE PYRIDINE-RING-CONTAINING CHELATE RESIN WHICH HAS UNDERGONE THE ELUTION STEP (B), SERVING AS A DISPLACEMENT LIQUID, THEREBY REGENERATING THE RESIN. |
