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:
Feb. 02, 1999
Filed:
Nov. 18, 1997
William S Carey, Wallingford, PA (US);
Libardo A Perez, Morrisville, PA (US);
Donald T Freese, Chadds Ford, PA (US);
Judith L Barron, Doylestown, PA (US);
BetzDearborn Inc., Trevose, PA (US);
Abstract
A composition for of controlling scale formation and deposition and corrosion in aqueous systems is described wherein a treatment solution of a substoichiometric amount of a composition comprising a scale/corrosion inhibitor in combination with a substituted alkylpolycarboxylate is employed. The scale/corrosion inhibitor can be a phosphonate such as hydroxyethylidene diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, hydroxyphosphonoacetic acids, amino phosphonates; terpolymers, copolymers and homopolymers of acrylic acid, maleic acid, epoxysuccinic acids such as polyepoxysuccinic acid or mixtures thereof. The substituted alkylpolycarboxylates are compounds of the general structure: R--X.sub.m --Y.sub.n wherein R is a hydrocarbon functionality having 4 to 18 carbons; X, when present, is --NH--, --NY.sup.1 --, --N-->O, --N--OC--Y.sup.1, --O-- or --S--; n is greater than or equal to 1; m=O or 1; and Y and Y.sup.1 each independently represent a substituted or nonsubstituted carboxylic acid functionality such that said alkylpolycarboxylate has at least 2 carboxylic acid functional groups.