PRODUCTION OF CRYSTAL ADDUCT OF BISPHENOL A WITH PHENOL HAVING EXCELLENT HUE

• Main Authors: SHIMODA KEIJI, KAMEDA TAKAO, MORIYA NOBUO, ASAOKA SACHIO
• Format: Patent
• Language: English
• Published: 21.05.1993
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY

PURPOSE:To efficiently obtain the subject adduct having excellent hue by a small-sized device by forming seed crystal from a bisphenol A-containing phenol solution by a crystallization column, growing crystal at a lower temperature, separating crystal adduct, redissolving the adduct in phenol and crystallizing. CONSTITUTION:A phenol solution having dissolved bisphenol A is fed to a first crystallization column A to carry out first-stage crystallization, a seed crystal-containing crystallization product obtained by the crystallizing operation is sent to a second distillation column B, crystal growth of the seed crystal is done at a lower temperature than that of the first crystallization column A, and the crystallization product is introduced to a solid-liquid separating device E. Crystal adduct thus formed is separated from the mother liquor, the crystal adduct is redissolved in phenol having a higher purity than the mother liquor by a crystal adduct dissolving tank F and fed to a first crystallization column C of two crystallization columns connected in series to carry out second crystallization. The crystal adduct-containing crystallization product obtained by the crystallization is sent to a second crystallization column D and crystal growth of the seed crystal is carried out at a temperature lower than that of the first crystallization column C.