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:
Jun. 01, 1976
Filed:
Jun. 17, 1974
James S Clovis, Morrisville, PA (US);
Jerome Dohling, Huntingdon Valley, PA (US);
Rohm and Haas Company, Philadelphia, PA (US);
Abstract
A process is disclosed for distilling corrosive carboxylic acids free of olefinic unsaturation in distillation apparatus constructed of corrodible metal, which includes the steps of introducing a crude dilute solution of such a corrosive acid into the distillation zone, distilling in the presence of an effective amount of p-benzoquinone or of 1,4-naphthoquinone, and recovering the concentrated corrosive acid outside the distillation zone. The amount of p-benzoquinone or of 1,4-naphthoquinone is such as to effectively prevent or reduce to acceptable limits the corrosion of the metal distillation apparatus by such acids, and also to permit this distillation process to be effectuated at those high acid vapor temperatures which otherwise would not be feasible because of the heightened degree of corrosiveness exhibited by the acids at such temperatures.