| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for obtaining highly purified bis-β-hydroxyethyl terephthalate. SOLUTION: This method for purifying bis-β-hydroxyethyl terephthalate comprises the following two steps: (1) crude bis-β-hydroxyethyl terephthalate containing a total of <=50 ppm of (i) cations consisting of Na, Mg, Ca, Fe, Co, Zn, Ti, Sn Sb, Ge and P and (ii) anions consisting of halogens, NO2, NO3, PO4 and SO4 is put to crystallization and (2) the thus crystallized bis-β- hydroxyethyl terephthalate is evaporated or distilled under reduced pressure.
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