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. 20, 1993
Filed:
Feb. 19, 1991
E Deniz Yalvac, Midland, MI (US);
Richard G Melcher, Midland, MI (US);
Robert A Bredeweg, Midland, MI (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
A chemical analysis method for the determination of a first organic acid in the presence of a second organic acid both of which are in a solution to be analyzed, the pK.sub.a of the first acid being at least 2 pK.sub.a units larger than the pK.sub.a of the second acid. The method includes three steps. The first step if to form a pH adjusted solution to be analyzed by adjusting the pH of the solution to be analyzed to be between the pK.sub.a of the first acid and the pK.sub.a of the second acid so that the first acid is predominately in its unionized form and so that the second acid is predominately in its ionized form. The second step is to partition the pH adjusted solution to be analyzed from a receiving solution with a semipermeable membrane, the semipermeable membrane being more permeable to the unionized form of the first acid than to the ionized form of the second acid, the first acid being soluble in the receiving solution so that the first acid permeates into the membrane from the pH adjusted solution to be analyzed and then permeates out of the membrane into the receiving solution. The last step is to determine the concentration of the first acid in the receiving solution so that the concentration of the first acid in the solution to be analyzed can be estimated.