Process for direct esterification of terephthalic acid with an alkylene glycol
Abstract
Abstract DIRECT ESTERIFICATION OF TEREPHTHALIC ACID AND AN ALKYLENE GLYCOL IS EXPEDITED BY FORMING A FINE DISPERSION OF THE INGREDIENTS AIDED BY A DISPERSING AND WETTING AGENT. THE ESTERIFICATION REACTION CAN BE CARRIED OUT IN THE PRESENCE OF A SMALL QUANTITY OF A SOLVENT WHICH CAUSES SUCCESSIVE QUANTITIES OF ACID TO ENTER THE LIQUID PHASE AND TO REACT TO FORM MOLTEN ESTERS WHICH THEN INCREASE THE TOTAL QUANTITY OF LIQUID PHASE PRESENT IN THE MIXTURE. THE PROCESS ENABLES THE ESTERIFICATION REACTION TO BE CARRIED OUT PRACTICALLY AT ATOMOSPHERIC PRESSURE OR TO BE CARRIED OUT AT SUPER ATMOSPHERIC PRESSURE IN A SHORTER TIME SPAN THAN IS THE CASE IN ESTERFICATION PROCESSES HERETOFORE AVAILABLE.
Inventors
- 👤 Stanley D Lazarus
Bibliographic Details
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