Process of manufacturing para-tert-butyl-phenol

Claim 1

IN A PROCESS OF MANUFACTURING PARA-TERBUTYLPHENOL FROM PHENOL AND ISOBUTENE WHICH COMPRISES REACTING SAID ISOBUTENE WITH LIQUID PHENOL MIXED WITH AN ACID-ACTIVATED CLAY, THE IMPROVEMENT COMPRISING PROVIDING SAID ISOBUTENE IN THE FORM OF A GASEOUS MIXTURE WITH NORMAL BUTENES, AND WHEREIN THE REACTION MIXTURE CONTAINS A QUANTITY OF MOISTURE REPRESENTING 0.5 TO 5 PERCENT BY WEIGHT OF WATER WITH RESPECT TO PHENOL, THE REACTION BEING CARRIED OUT IN TWO STAGES COMPRISING (1) MAINTAINING THE LIQUID MIXTURE AT A TEMPERATURE NOT EXCEEDING 55*C. IN THE PRESENCE OF SAID ACID-ACTIVATED CLAY AND SAID WATER AND DURING FEEDING OF SAID GASEOUS MIXTURE AND (2) THEN, STOPPING THE INTRODUCTION OF SAID GASEOUS MIXTURE AT A POINT SUCH THAT AFTER THE OLEFIN INTRODUCTION STEP THE MOLAR RATIO OF FREE OR COMBINED PHENOL IN THE REACTION MASS TO FIXED ISOBUTENE IS NOT LOWER THAN 1.5, AND SUBMITTING THE REACTION MIXTURE WITHOUT INTERMEDIATE TREATMENT TO A TEMPERATURE OF ABOUT 110*C, TO ABOUT 120*C. WHILE DEHYDRATING IT BY AZEOTROPIC DISTILLATION.