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:
May. 19, 2026
Filed:
Feb. 06, 2019
Basf SE, Ludwigshafen am Rhein, DE;
Andrey Karpov, Ludwigshafen am Rhein, DE;
Andreas Lehr, Ludwigshafen am Rhein, DE;
Daniela Rieck, Ludwigshafen am Rhein, DE;
Holger Borchert, Ludwigshafen am Rhein, DE;
Tobias Weinland, Ludwigshafen am Rhein, DE;
Marco Bosch, Ludwigshafen am Rhein, DE;
Christian Walsdorff, Ludwigshafen am Rhein, DE;
Christian Bartosch, Ludwigshafen am Rhein, DE;
Juergen Zuehlke, Ludwigshafen am Rhein, DE;
BASF SE, Ludwigshafen am Rhein, DE;
Abstract
A method for preparing a silver impregnation solution comprises (a) charging a neutralization reactor R1 with an aqueous organic amine; (b) adding oxalic acid powder through a first feeding conduit to the neutralization reactor R1 to obtain an aqueous oxalic acid-organic amine solution; (c) directing the aqueous oxalic acid-organic amine solution from the neutralization reactor to a complexation reactor R2; (d) adding particulate silver oxide through a second feeding conduit to the complexation reactor R2 to obtain a silver impregnation solution; and, optionally, (e) subjecting the silver impregnation solution to filtration. The silver impregnation solution is used for producing a catalyst effective in the oxidative conversion of ethylene to ethylene oxide. The method allows for the preparation of a silver impregnation solution in an efficient and occupationally and environmentally safe way. Security hazards which can occur when oxalic acid and silver oxide are added to an aqueous amine solution using the same powder feeding equipment or the same reactor are avoided.