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US 6,585,933 B1Granted
Method and composition for inhibiting corrosion in aqueous systems
AssigneeBetzDearborn Inc.
InventorsWilliam C. Ehrhardt, Longchun Cheng, Dawn Stasney, Kim A. Whitaker
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Abstract
A method and composition for controlling corrosion of metals, particularly ferrous-based metals in contact with aqueous systems is disclosed, which includes treating industrial waters with a combination of a tetrazolium salt of the general formula: where R1, R2 and R3 may be various organic or inorganic substitutents, where n may be 1 or 2, and at least one other aqueous system treatment material.
Claims162
A method for controlling the corrosion of metals in contact with an aqueous system at a pH of about 5 to about 12 which comprises introducing into said system a combination of:
- (a) a tetrazolium compound of the formula:
- wherein R1, R2 and R3 are selected from the group consisting of lower alkyl, branched lower alkyl, aryl, substituted aryl, alkylaryl, substituted alkyaryl and heterocyclic substituted aryl, with the proviso that neither R1, R2, or R3 contain more than 14 carbon atoms;
- and n is 1 or 2, such tetrazolium compound optionally having associated water soluble ionic species if needed to obtain a neutral charge, and
- (b) at least one other aqueous system treatment material chosen so that the material does not substantially reduce the tetrazolium compound selected from the group consisting of inorganic phosphates;
- nitrites;
- compounds that release a metal anion in water;
- 2,3-dihydroxybenzoic acid;
- 1,10-phenanthroline;
- polycarboxylates;
- alkyl hydroxylcarboxylate acids;
- aminohydroxysuccinic acids;
- carboxyamines;
- polyepoxysuccinic acids;
- modified polyepoxysuccinic acids;
- monophosphonic acids;
- diphosphonic acids;
- phosphonocarboxylic acids;
- hydroxyphosphonocarboxylic acids;
- aminophosphonic acids;
- phosphonomethylamine oxides;
- polymeric amine oxides;
- polyetherpolyaminomethylene phosphonates;
- polyetherpolyamino-methylene phosphonate N-oxides;
- long chain fatty acids derivatives of sarcosine;
- telomeric, co-telomeric, polymeric or copolymeric phosphorus-containing carboxylates;
- amines;
- diamines;
- alkanolamines;
- fatty amines and diamines;
- quaternized amines;
- oxyalkylated amines;
- alkyl pyridines;
- benzoates;
- substituted benzoates;
- straight chain C5-C11 monocarboxylates;
- C4-C15α,ω-dicarboxylates;
- amine salts of carboxylic acids;
- mercaptocarboxylic acids;
- amino acids;
- polyamino acids;
- dicarboxylic acids;
- tricarboxylic acids;
- phosphoesters;
- phosphate esters;
- water soluble salts thereof and mixtures thereof, wherein the weight ratio of component (b) to component (a) is from about 100:1 to about 1:20.
42 more elements
A method for controlling corrosion, deposition, and scale in an aqueous system at a pH of about 5 to about 12 which comprises introducing into said system a combination of:
- (a) a tetrazolium compound of the formula:
- wherein R1, R2 and R3 are selected from the group consisting of lower alkyl, branched lower alkyl, aryl, substituted aryl, alkylaryl, substituted alkyaryl and heterocyclic substituted aryl, with the proviso that neither R1, R2, or R3 contain more than 14 carbon atoms;
- and n is 1 or 2, such tetrazolium compound optionally having associated water soluble ionic species if needed to obtain a neutral charge, and
- (b) at least one other aqueous system treatment material chosen so that the material does not substantially reduce the tetrazolium compound selected from the group consisting of inorganic phosphates;
- nitrites;
- compounds that release a metal anion in water;
- 2,3-dihydroxybenzoic acid;
- 1,10-phenanthroline;
- polycarboxylates;
- alkyl hydroxylcarboxylate acids;
- aminohydroxysuccinic acids;
- carboxyamines;
- polyepoxysuccinic acids;
- modified polyepoxysuccinic acids;
- monophosphonic acids;
- diphosphonic acids;
- phosphonocarboxylic acids;
- hydroxyphosphonocarboxylic acids;
- aminophosphonic acids;
- phosphonomethylamine oxides;
- polymeric amine oxides;
- polyetherpolyaminomethylene phosphonates;
- polyetherpolyamino-methylene phosphonate N-oxides;
- long chain fatty acids derivatives of sarcosine;
- telomeric, co-telomeric, polymeric or copolymeric phosphorus-containing carboxylates;
- amines;
- diamines;
- alkanolamines;
- fatty amines and diamines;
- quaternized amines;
- oxyalkylated amines;
- alkyl pyridines;
- benzoates;
- substituted benzoates;
- straight chain C5-C11 monocarboxylates;
- C4-C15α,ω-dicarboxylates;
- amine salts of carboxylic acids;
- mercaptocarboxylic acids;
- amino acids;
- polyamino acids;
- dicarboxylic acids;
- tricarboxylic acids;
- phosphoesters;
- phosphate esters;
- water soluble salts thereof and mixtures thereof, and additionally selected so that at least one of these treatments is effective in inhibiting scale and/or deposition, wherein the weight ratio of component (b) to component (a) is from about 100:1 to about 1:20.
42 more elements
Dependencies are inferred from the claim text.