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:
Aug. 10, 1999
Filed:
Sep. 05, 1996
Applicant:
Inventors:
Gary A O'Neill, Tyngsboro, MA (US);
Kitty K Siu, Dracut, MA (US);
Jeffrey P Denoncourt, Winchester, MA (US);
Assignee:
Millipore Corporation, Bedford, MA (US);
Primary Examiner:
Int. Cl.
CPC ...
C02F / ;
U.S. Cl.
CPC ...
210638 ; 210664 ; 210668 ; 210669 ; 210677 ; 210900 ;
Abstract
Ultrapure water containing less than 10 ppt total ions, other than hydrogen ion and hydroxide ion is produced by passing deionized water through a system comprising an ultrafiltration step, an oxidizing step where water is exposed to ultraviolet light and ion exchange step. The treated water is recirculated through the oxidizing step and the ion exchange step. Product water from the system can be recovered on a continuous basis so long as the ratio of volume of water circulated within the system to volume of water drawn from the system is at least 10 and preferably at least 20.