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:
Jan. 23, 1990
Filed:
Feb. 08, 1988
Hans P Schneider, Stade, DE;
Ulrich Wallbaum, Dollern, DE;
The Dow Chemical Company, Midland, MI (US);
Abstract
Improved processes for the removal from solution of multi-valent alkaline earth metal and/or heavy metal cations are taught, having excellent combinations of cation capacity and resistance to bead breakage. The processes use specified polymer resin beads functionalized with chelating functionalities such as alkylaminophosphonic moieties or iminodiacetic acid moieties. The beads are prepared by the specified process to have a decreased amount of cross-linking in the shell area as compared to the core. An additional aspect of the invention is an improved gel-type chelating resin having core/shell morphology and alkylaminophosphonic functional groups which is found to exhibit surprising combinations of dynamic capacity, osmotic shock resistance, and physical strength. This chelating resin has been found to be very suitable for the removal of calcium from brine solutions prior to the use of such solutions in membrane electrolysis cells of chlorine production.