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:
Feb. 21, 1984
Filed:
Jan. 28, 1982
Samuel N Holter, Pittsburgh, PA (US);
Koppers Company, Inc., Pittsburgh, PA (US);
Abstract
A process is provided for recovering the crystallization medium used for separating a 2,6-disubstituted phenol (DSP) from a feedstock containing it and a phenol in which only one of the 2 or 6 carbon positions are substituted (MSP). More particularly, the process comprises crystallizing said DSP from said feedstock with a water miscible non solvent crystallization medium, separating the resultant DSP crystals from said crystallization medium and feedstock, washing said DSP crystals with crystallization medium, washing said DSP crystals with water, passing the aforesaid wash water and crystallization medium along with the crystallization medium and feedstock from which the DSP was crystallized to an extraction means and extracting MSP with a water immiscible and crystallization medium immiscible extractant, stripping the extractant from the MSP and recycling the extractant to the extraction means and separating water from the crystallization medium of the extraction means and recycling the water for use in the water wash or extraction means and recycling the crystallization medium for the initial crystallization, the wash of the DSP crystals, or to the extraction means.