Abstract 1. A PROCESS FOR THE PURIFICATION OF IMPURE TEREPHTHALIC ACID WHICH COMPRISES: FORMING A FIRST SOLUTION AMMONIUM TEREPHTHALATE BY CONTACTING TEREPHTHALIC ACID TO BE PURIFIED WITH AMMONIA WATER CONTAINING FROM ABOUT 10 TO ABOUT 35% BY WEIGHT AMMONIA AT A TEMPERATURE OF AT LEAST 10* C. AND NOT IN EXCESS OF 100* C. IN AN AMOUNT IN EXCESS OF AT LEAST 150% OF A STOICHIOMETRIC QUANTITY OF AMMONIA NEEDED TO REACT WITH SAID TEREPHTHALIC ACID AND IN AN AMOUNT NECESSARY TO FORM AN UNSTURATED SOLUTION CONTAINING FROM 10 TO 17% BY WEIGHT REACTED TEREPHTHALIC ACID SO AS TO REACT SAID TEREPHTHALIC ACID WITH SAID AMMONIA TO FORM AMMONIUM TEREPHTHALATE IN AN AQUEOUS UNSATURATED SOLUTION, SEPARATING AMMONIUM TEREPHTHALATE FROM THE REMAINDER OR SAID SOLUTION, DECOMPOSING SAID AMMONIUM TEREPHTHALATE TO FORM A PARTIALLY PURIFIED TEREPHTHALATE ACID PRODUCT HY HEATING SAID AMMONIUM TEREPHTHALATE AT A TEMPERATUTE OF AT LEAST ABOUT 275* C. AT WHICH IMPURITIES IN SAID AMMONIUM TEREPHTHALATE ARE VOLATILE AND AT A TEMPERATURE AT WHICH SAID AMMONIUM TEREPHTHALATE DECOMPOSES TO PRODUCE TEREPHTHALIC ACID, BUT AT A TEMPERATURE BELOW ABOUT 300* C. SO AS TO AVOID SUBLIMATION OF TEREPHTHALIC ACID, FORMING A FURTHER SOLUTION OF AMMONIUM TEREPHTHALATE BY CONTACTING SAID PARTIALLY PURIFIED TEREPHTHALIC ACID WITH AMMONIA WATER CONTAINING FROM ABOUT 10 TO ABOUT 35% BY WEIGHT AMMONIA AT A TEMPERATURE OF AT LEAST 10* C. AND NOT IN EXCESS OF 100* C. IN AN AMOUNT IN EXCESS OF AT LEAST 150% OF A STOICHIOMETRIC QUANTITY OF AMMONIA NEEDED TO REACT WITH SAID TEREPHTHALIC ACID AND IN AN AMOUNT NECESSARY TO FORM AN UNSATURATED SOLUTION CONTAINING FROM 10 TO 17% BY WEIGHT REACTED TEREPHTHALIC ACID SO AS TO REACT SAID PARTIALLY PURIFIED TEREPHTHALIC ACID WITH SAID AMMONIA TO FORM AMMONIUM TEREPHTHALATE IN AN AQUEOUS UNSTURATED SOLUTION, SEPARATING SAID AMMONIUM TEREPHTHALATE FROM SAID FURTHER SOLUTION, AND DECOMPOSING SAID AMMONIUM TEREPHTHALATE TO PRODUCE TEREPHTHALIC ACID BY HEATING SAID AMMONIUM TEREPHTHALATE AT A TEMPERATURE OF AT LEAST 275* C. AT WHICH IMPURITIES IN SAID AMMONIUM TEREKPHTHALATE DECOMPOSE TO PRODUCE TEREPHTHALIC ACID, BUT AT A TEMPERATURE BELOW 300* C. SO AS TO AVOID THE SUBLIMATION OF SAID AMMONIUM TEREPHTHALATE, ONE OF SAID SEPARATING STEPS AND THE DECOMPOSING STEP IMMEDIATELY FOLLOWING IT BEING CARRIED OUT BY HEATING THE SOLUTION TREATED DURING SUCH STEP AT ITS BOILING POINT SO AS TO SEPARATE SAID AMMONIUM TEREPHTHALATE, VOLATIZING THE REMAINDER OF SAID SOLUTION BEING SEPARATED AND FURTHER HEATING THE AMMONIUM TEREPHTHALATE SO SEPARATED SO AS TO DECOMPOSE THE SAME, AND THE OTHER OF SAID SEPARATING STEPS BEING CARRIED OUT BY CONTACTING THE SOLUTION TREATED DURING SUCH STEP WITH AMMONIA GAS UNTIL AMMONIUM TEREPHTHALATE IS PRECIPITATED AND PHYSICALLY REMOVING THE PRECIPITATED AMMONIUM TEREPHTHALATE FROM THE SOLUTION FROM WHICH IT IS PRECIPITATED.
Inventors
👤 H Rudzki
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-09 03:29
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/02; C07C51/42
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
448 words
A PROCESS FOR THE PURIFICATION OF IMPURE TEREPHTHALIC ACID WHICH COMPRISES: FORMING A FIRST SOLUTION AMMONIUM TEREPHTHALATE BY CONTACTING TEREPHTHALIC ACID TO BE PURIFIED WITH AMMONIA WATER CONTAINING FROM ABOUT 10 TO ABOUT 35% BY WEIGHT AMMONIA AT A TEMPERATURE OF AT LEAST 10* C. AND NOT IN EXCESS OF 100* C. IN AN AMOUNT IN EXCESS OF AT LEAST 150% OF A STOICHIOMETRIC QUANTITY OF AMMONIA NEEDED TO REACT WITH SAID TEREPHTHALIC ACID AND IN AN AMOUNT NECESSARY TO FORM AN UNSTURATED SOLUTION CONTAINING FROM 10 TO 17% BY WEIGHT REACTED TEREPHTHALIC ACID SO AS TO REACT SAID TEREPHTHALIC ACID WITH SAID AMMONIA TO FORM AMMONIUM TEREPHTHALATE IN AN AQUEOUS UNSATURATED SOLUTION, SEPARATING AMMONIUM TEREPHTHALATE FROM THE REMAINDER OR SAID SOLUTION, DECOMPOSING SAID AMMONIUM TEREPHTHALATE TO FORM A PARTIALLY PURIFIED TEREPHTHALATE ACID PRODUCT HY HEATING SAID AMMONIUM TEREPHTHALATE AT A TEMPERATUTE OF AT LEAST ABOUT 275* C. AT WHICH IMPURITIES IN SAID AMMONIUM TEREPHTHALATE ARE VOLATILE AND AT A TEMPERATURE AT WHICH SAID AMMONIUM TEREPHTHALATE DECOMPOSES TO PRODUCE TEREPHTHALIC ACID, BUT AT A TEMPERATURE BELOW ABOUT 300* C. SO AS TO AVOID SUBLIMATION OF TEREPHTHALIC ACID, FORMING A FURTHER SOLUTION OF AMMONIUM TEREPHTHALATE BY CONTACTING SAID PARTIALLY PURIFIED TEREPHTHALIC ACID WITH AMMONIA WATER CONTAINING FROM ABOUT 10 TO ABOUT 35% BY WEIGHT AMMONIA AT A TEMPERATURE OF AT LEAST 10* C. AND NOT IN EXCESS OF 100* C. IN AN AMOUNT IN EXCESS OF AT LEAST 150% OF A STOICHIOMETRIC QUANTITY OF AMMONIA NEEDED TO REACT WITH SAID TEREPHTHALIC ACID AND IN AN AMOUNT NECESSARY TO FORM AN UNSATURATED SOLUTION CONTAINING FROM 10 TO 17% BY WEIGHT REACTED TEREPHTHALIC ACID SO AS TO REACT SAID PARTIALLY PURIFIED TEREPHTHALIC ACID WITH SAID AMMONIA TO FORM AMMONIUM TEREPHTHALATE IN AN AQUEOUS UNSTURATED SOLUTION, SEPARATING SAID AMMONIUM TEREPHTHALATE FROM SAID FURTHER SOLUTION, AND DECOMPOSING SAID AMMONIUM TEREPHTHALATE TO PRODUCE TEREPHTHALIC ACID BY HEATING SAID AMMONIUM TEREPHTHALATE AT A TEMPERATURE OF AT LEAST 275* C. AT WHICH IMPURITIES IN SAID AMMONIUM TEREKPHTHALATE DECOMPOSE TO PRODUCE TEREPHTHALIC ACID, BUT AT A TEMPERATURE BELOW 300* C. SO AS TO AVOID THE SUBLIMATION OF SAID AMMONIUM TEREPHTHALATE, ONE OF SAID SEPARATING STEPS AND THE DECOMPOSING STEP IMMEDIATELY FOLLOWING IT BEING CARRIED OUT BY HEATING THE SOLUTION TREATED DURING SUCH STEP AT ITS BOILING POINT SO AS TO SEPARATE SAID AMMONIUM TEREPHTHALATE, VOLATIZING THE REMAINDER OF SAID SOLUTION BEING SEPARATED AND FURTHER HEATING THE AMMONIUM TEREPHTHALATE SO SEPARATED SO AS TO DECOMPOSE THE SAME, AND THE OTHER OF SAID SEPARATING STEPS BEING CARRIED OUT BY CONTACTING THE SOLUTION TREATED DURING SUCH STEP WITH AMMONIA GAS UNTIL AMMONIUM TEREPHTHALATE IS PRECIPITATED AND PHYSICALLY REMOVING THE PRECIPITATED AMMONIUM TEREPHTHALATE FROM THE SOLUTION FROM WHICH IT IS PRECIPITATED.
Claim 2
Dependent Claim
448 words
A PROCESS FOR THE PURIFICATION OF IMPURE TEREPHTHALIC ACID WHICH COMPRISES: FORMING A FIRST SOLUTION AMMONIUM TEREPHTHALATE BY CONTACTING TEREPHTHALIC ACID TO BE PURIFIED WITH AMMONIA WATER CONTAINING FROM ABOUT 10 TO ABOUT 35% BY WEIGHT AMMONIA AT A TEMPERATURE OF AT LEAST 10* C. AND NOT IN EXCESS OF 100* C. IN AN AMOUNT IN EXCESS OF AT LEAST 150% OF A STOICHIOMETRIC QUANTITY OF AMMONIA NEEDED TO REACT WITH SAID TEREPHTHALIC ACID AND IN AN AMOUNT NECESSARY TO FORM AN UNSTURATED SOLUTION CONTAINING FROM 10 TO 17% BY WEIGHT REACTED TEREPHTHALIC ACID SO AS TO REACT SAID TEREPHTHALIC ACID WITH SAID AMMONIA TO FORM AMMONIUM TEREPHTHALATE IN AN AQUEOUS UNSATURATED SOLUTION, SEPARATING AMMONIUM TEREPHTHALATE FROM THE REMAINDER OR SAID SOLUTION, DECOMPOSING SAID AMMONIUM TEREPHTHALATE TO FORM A PARTIALLY PURIFIED TEREPHTHALATE ACID PRODUCT HY HEATING SAID AMMONIUM TEREPHTHALATE AT A TEMPERATUTE OF AT LEAST ABOUT 275* C. AT WHICH IMPURITIES IN SAID AMMONIUM TEREPHTHALATE ARE VOLATILE AND AT A TEMPERATURE AT WHICH SAID AMMONIUM TEREPHTHALATE DECOMPOSES TO PRODUCE TEREPHTHALIC ACID, BUT AT A TEMPERATURE BELOW ABOUT 300* C. SO AS TO AVOID SUBLIMATION OF TEREPHTHALIC ACID, FORMING A FURTHER SOLUTION OF AMMONIUM TEREPHTHALATE BY CONTACTING SAID PARTIALLY PURIFIED TEREPHTHALIC ACID WITH AMMONIA WATER CONTAINING FROM ABOUT 10 TO ABOUT 35% BY WEIGHT AMMONIA AT A TEMPERATURE OF AT LEAST 10* C. AND NOT IN EXCESS OF 100* C. IN AN AMOUNT IN EXCESS OF AT LEAST 150% OF A STOICHIOMETRIC QUANTITY OF AMMONIA NEEDED TO REACT WITH SAID TEREPHTHALIC ACID AND IN AN AMOUNT NECESSARY TO FORM AN UNSATURATED SOLUTION CONTAINING FROM 10 TO 17% BY WEIGHT REACTED TEREPHTHALIC ACID SO AS TO REACT SAID PARTIALLY PURIFIED TEREPHTHALIC ACID WITH SAID AMMONIA TO FORM AMMONIUM TEREPHTHALATE IN AN AQUEOUS UNSTURATED SOLUTION, SEPARATING SAID AMMONIUM TEREPHTHALATE FROM SAID FURTHER SOLUTION, AND DECOMPOSING SAID AMMONIUM TEREPHTHALATE TO PRODUCE TEREPHTHALIC ACID BY HEATING SAID AMMONIUM TEREPHTHALATE AT A TEMPERATURE OF AT LEAST 275* C. AT WHICH IMPURITIES IN SAID AMMONIUM TEREKPHTHALATE DECOMPOSE TO PRODUCE TEREPHTHALIC ACID, BUT AT A TEMPERATURE BELOW 300* C. SO AS TO AVOID THE SUBLIMATION OF SAID AMMONIUM TEREPHTHALATE, ONE OF SAID SEPARATING STEPS AND THE DECOMPOSING STEP IMMEDIATELY FOLLOWING IT BEING CARRIED OUT BY HEATING THE SOLUTION TREATED DURING SUCH STEP AT ITS BOILING POINT SO AS TO SEPARATE SAID AMMONIUM TEREPHTHALATE, VOLATIZING THE REMAINDER OF SAID SOLUTION BEING SEPARATED AND FURTHER HEATING THE AMMONIUM TEREPHTHALATE SO SEPARATED SO AS TO DECOMPOSE THE SAME, AND THE OTHER OF SAID SEPARATING STEPS BEING CARRIED OUT BY CONTACTING THE SOLUTION TREATED DURING SUCH STEP WITH AMMONIA GAS UNTIL AMMONIUM TEREPHTHALATE IS PRECIPITATED AND PHYSICALLY REMOVING THE PRECIPITATED AMMONIUM TEREPHTHALATE FROM THE SOLUTION FROM WHICH IT IS PRECIPITATED.