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:
Oct. 26, 2021
Filed:
Jul. 12, 2019
Kureha Corporation, Tokyo, JP;
KUREHA CORPORATION, Tokyo, JP;
Abstract
The continuous dehydration method for a raw material mixture to be used in the production of PAS includes supply and dehydration of the raw material mixture and extraction of the raw material mixture having a water content reduced by the dehydration, the supply, dehydration and extraction being carried out concurrently in parallel. A dehydration efficiency index determined according to Equation (1) is not less than 0.3. In Equation (1), the dehydration time is a period of time until a moisture content per mole of the sulfur source in the raw material mixture having a reduced water content reaches not greater than 1.7 mol, including moisture consumed by the hydrolysis of the organic polar solvent.Dehydration efficiency index=[Number of moles (mol) of the sulfur source in the raw material mixture having a reduced water content]/[Dehydration time (hr)×(Total internal volume (L) of the dehydration tanks)]  (1)