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:
Apr. 01, 2008
Filed:
Feb. 28, 2003
Gunther Windecker, Ludwigshafen, DE;
Alexander Weck, Freinsheim, DE;
Rolf-hartmuth Fischer, Heidelberg, DE;
Markus Rösch, Oppenheim, DE;
Nils Bottke, Mannheim, DE;
Michael Hesse, Worms, DE;
Stephan Schlitter, Ludwigshafen, DE;
Holger Borchert, Offstein, DE;
Gunther Windecker, Ludwigshafen, DE;
Alexander Weck, Freinsheim, DE;
Rolf-Hartmuth Fischer, Heidelberg, DE;
Markus Rösch, Oppenheim, DE;
Nils Bottke, Mannheim, DE;
Michael Hesse, Worms, DE;
Stephan Schlitter, Ludwigshafen, DE;
Holger Borchert, Offstein, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
Crude water-containing tetrahydrofuran is purified by passing the crude tetrahydrofuran through three distillation columns, withdrawing water from the bottom of the first column, recycling water-containing tetrahydrofuran from the top of the second column into the first column, passing a sidestream of the first column into the second column, recycling the bottom product of the third column into the first column, and withdrawing a distillate at the top of the first column. Additionally, a sidestream of the second column is passed into the third column and the purified tetrahydrofuran is recovered as the top product of the third column.