The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 21, 1990
Filed:
Feb. 14, 1989
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Abstract
A process for washing and obtaining solids of a slurry comprises feeding a slurry containing the adduct of bisphenol A with phenol crystallized from a phenol solution of bisphenol A to a first solid-liquid separator to separate solids from the slurry, transferring the solids separated by the first solid-liquid separator to an agitation tank in which the solids are reslurried, feeding the slurry obtained in the agitation tank to a second solid-liquid separator, said second solid-liquid separator being intended to obtain the solids from the slurry discharged from the agitation tank, and permitting the admission of a washing solvent to wash the solids, and permitting the filtrate and washings to be recovered independently, feeding the washing solvent to the second solid-liquid separator, feeding all of the washings from the second solid-liquid separator to the agitation tank, feeding a part of the filtrate from the second solid-liquid separator to the agitation tank, and discharging the remainder of the filtrate from the system. The process makes it possible to produce a high-purity adduct of bisphenol A with phenol and hence high-purity bisphenol A.