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. 11, 2000
Filed:
Oct. 22, 1998
Rudolf Boensch, Nackenheim, DE;
Klaus Hohmann, Hofheim, DE;
Juergen Kuhn, Frankfurt am Main, DE;
Vaclav Cerny, Kaznejov, CS;
Frantisek Hotek, Petrohrad, CS;
Jiri Pendl, Pilzen, CS;
Metallgesellschaft Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
Citric acid and/or the salts thereof are produced from a raw material containing carbohydrates. An aqueous solution of the raw material is converted into a first solution containing citric acid by means of fermentation, and from the first solution a second solution containing citric acid is obtained by means of a cell separation. The second solution is subjected to a protein precipitation at temperatures of 2 to 70.degree. C., and protein is separated by filtration. From the filtration, a third solution containing citric acid is obtained, and the same is passed through a first anion exchanger. The solution containing citric acid, which is discharged from the first anion exchanger, is passed through a second anion exchanger, which is selectively charged with citric acid. The second anion exchanger charged with citric acid is eluted with hydroxide solution or water, and there is thus obtained a fourth solution, in which citrate or citric acid is dissolved. Water is at least partly removed from the fourth solution.