Process for the purification of crude bis-(beta-hydroxyethyl) terephthalate
Abstract
Abstract A PROCESS FOR PURIFYING CRUDE BIS-(B-HYDROXYETHYL) TEREPHTHALATE PREPARED BY THE REACTION OF TEREPHTHALIC ACID OR DIMETHYL TEREPHTHALATE WITH ETHYLENE GLYCOL OR ETHYLENE OXIDE WHICH COMPRISES DISSOLVING THE CRUDE BIS-(B-HYDROXYETHYL) TEREPHTHALATE IN AN AROMATIC SOLVENT AT A CONCENTRATION HIGHER THAN THE SATURATION SOLUBILITY OF THE CRUDE BIS(B-HYDROXYETHYL) TEREPHTHALATE IN THE SOLVENT AT A TERPERATURE CORRESPONDING TO THE APPARENT MELTING POINT OF THE SAME CRUDE BIS-(B-HYDROXYETHYL> TEREPHTHALATE IN THE SAME SOLVENT AT AN ELEVATED TEMPERATURE ABOVE THE APPARENT MELTING POINT AND RAPIDLY COOLING THE SOLUTION TO A TEMPERATURE BELOW THE APPARENT MELTING POINT, THEREBY AVOIDING THE PRECIPITATION OF GRANULAR OR BLOCKY SOLIDS OR BIS(B-HYDROXYETHYL) TEREPHTHALATE.
Inventors
- 👤 Yataro Ichikawa
- 👤 Michiyuki Tokashiki
- 👤 Nobuo Suzuki
Bibliographic Details
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