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. 15, 1978
Filed:
Feb. 02, 1976
Herbert Eck, Burghausen, DE;
Elmar Bethe, Burghausen, DE;
Hans Schwarzbauer, Burghausen, DE;
Hellmuth Spes, Burghausen, DE;
Klaus Kaiser, Burghausen, DE;
Wacker-Chemie GmbH, Munich, DE;
Abstract
A process for the purification of crude acetic anhydride by continuous fractional distillation, which comprises first introducing the anhydride into an evaporator, thereafter removing from the evaporator the non-distillable components contained in the crude anhydride, then introducing the distillable components of the anhydride in vapor form into about the central section of a fractionating column, withdrawing from the top of the column the low boiling components together with acetic acid, withdrawing near the bottom of the column a high-percentage of pure acetic anhydride, and separating from the sump of the column up to about 8% by weight based on the initial amount of crude acetic anhydride and returning the same to the evaporator.