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:
Jul. 31, 2001
Filed:
Jan. 05, 1998
Imre Toth, Geleen, NL;
Onko Gelling, Geleen, NL;
Rudolf P. M. Guit, Maastricht, NL;
Antonius J. F. Simons, Geleen, NL;
Simon Hans H. Niemann, Maastricht, NL;
Other;
Abstract
Process to separate linear 5-formylvaleric acid from a mixture of 5- and 3- and 4-formylvaleric acids, wherein the separation is performed by fractional extraction with two immiscible solvents of which one solvent is an aqueous solvent and the other solvent is an organic solvent, in which the organic solvent has a higher or lower affinity for 5-formylvaleric acid than its affinity for the 3-formylvaleric acids and for the 4-formylvaleric acid. Furthermore the invention relates to an improved process to prepare ∈-caprolactam starting from a mixture of branched and linear formylvaleric acids or starting from pentenoic acid.