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:
Jun. 07, 1983
Filed:
Oct. 09, 1981
Roger C May, Glenside, PA (US);
Frank C Sessa, Wyncote, PA (US);
Betz Laboratories, Inc., Trevose, PA (US);
Abstract
A method for inhibiting corrosion and controlling deposition in an iron containing aqueous medium is disclosed. The method is capable of providing for the formation of a protective passive oxide film on the metallic surfaces in contact with the aqueous medium without resulting in unacceptable iron based deposition or fouling. Surprisingly, the method does not call for the addition of an organic-phosphonic acid compound or derivative to the aqueous medium as would be normally expected due to the known iron dispersing characteristics of these type compounds. The invention comprises maintaining the pH level at 5.5 or above, assuring that a certain minimal calcium or other ion level is maintained, and adding to the system an orthophosphate compound and a water soluble acrylic acid/hydroxyalkylacrylate copolymer.