# US 6,811,747 B2 · Corrosion inhibitor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,811,747 B2 - Document ID: US6811747B2 - Status: Granted - Kind: B2 - Application number: 10/455,642 - Filed: 2003-06-04 - Published: 2003-12-18 - Granted: 2004-11-02 - Earliest claimed: 2002-06-12 - Assignees: BioQuest - Inventors: Michael A. Silveri - Web page: https://patentgrep.com/patent/US6811747B2 ## CPC - C23F 11/10: using organic inhibitors - C02F 1/76: with halogens or compounds of halogens {(C02F1/4674 takes precedence)} - C02F 2103/42: from bathing facilities, e.g. swimming pools - C02F 2303/08: Corrosion inhibition - Y02W 10/37: using solar energy - C23F: NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE (working metal by laser beams B23K26/00; desurfacing by applying flames B23K7/00; working of metal by electro-erosion B23H; producing decorative effects by removing surface material, e.g. by engraving, by etching, B44C1/22; electrolytic etching or polishing C25F); INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25 - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) - Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT ## Abstract The present invention relates to water treatment chemical formulations, and more particularly to chemical formulations used to treat water containing halogens as a sanitizing agent. The water treatment chemical formulations contain cyanuric acid and an alkali metal molybdate or silicate as an anticorrosion agent. ## Claims ### Claim 1 A composition for inhibiting pitting corrosion of a ferrous metal in contact with a metal-corrosive aqueous system, wherein the aqueous system comprises a halogen salt, the composition comprising: a) cyanuric acid; and b) at least one water-soluble salt selected from the group consisting of alkali metal molybdate salts, alkali metal silicate salts, and mixtures thereof, wherein the weight ratio of cyanuric acid to water soluble salt is from about 1:1 to about 200:1. ### Claim 2 (depends on 1) The composition of claim 1, further comprising a metal-corrosive aqueous system. ### Claim 3 (depends on 1) The composition of claim 1, wherein a concentration of cyanuric acid in the metal-corrosive aqueous system is from about 50 ppm to about 600 ppm. ### Claim 4 (depends on 3) The composition of claim 3, wherein the concentration of cyanuric acid in the metal-corrosive aqueous system is from about 50 ppm to about 300 ppm. ### Claim 5 (depends on 4) The composition of claim 4, wherein the concentration of cyanuric acid in the metal-corrosive aqueous system is about 300 ppm. ### Claim 6 (depends on 1) The composition of claim 1, wherein a concentration of water soluble salt in the metal-corrosive aqueous system is from about 3 ppm to about 50 ppm. ### Claim 7 (depends on 1) The composition of claim 1, wherein the water soluble salt comprises sodium silicate. ### Claim 8 (depends on 7) The composition of claim 7, wherein a concentration of sodium silicate in metal-corrosive aqueous system is from about 3 ppm to about 50 ppm. ### Claim 9 (depends on 8) The composition of claim 8, wherein the concentration of sodium silicate in the metal-corrosive aqueous system is about 11 ppm. ### Claim 10 (depends on 1) The composition of claim 1, wherein the water-soluble salt comprises sodium molybdate. ### Claim 11 (depends on 10) The composition of claim 10, wherein a concentration of sodium molibdate in the metal-corrosive aqueous system is from about 5 ppm to about 50 ppm. ### Claim 12 (depends on 11) The composition of claim 11, wherein the concentration of sodium molybdate in the metal-corrosive aqueous system is about 37 ppm. ### Claim 13 (depends on 1) The composition of claim 1, further comprising: c) sodium bromide, wherein the weight ratio of sodium bromide to cyanuric acid is from about 1:2 to about 40:1, and wherein the ratio of sodium bromide to water soluble salt is from about 100:1 to about 60:1. ### Claim 14 (depends on 1) The composition of claim 1, wherein the water soluble salt comprises sodium silicate and sodium molybdate, wherein the weight ratio of cyanuric acid to sodium silicate is from about 1:1 to about 200:1, and wherein the weight ratio of cyanuric acid to sodium molybdate is from about 1:1 to about 200:1. ### Claim 15 (depends on 1) The composition of claim 1, further comprising: d) a substance selected from the group consisting of sodium carbonate, polyacrylate homopolymer, and 2-phosphonobutane-1,2,4-tricarboxylic acid. ### Claim 16 A composition for inhibiting the corrosion of a ferrous metal in contact with a metal-corrosive aqueous system, the composition comprising: a) from about 0.02 to about 66 wt. % cyanuric acid; b) from about 0.001 to about 13 wt. % sodium molybdate; c) from about 0.002 to about 13 wt. % sodium silicate; and d) from about 30 to about 97 wt. % sodium bromide. ### Claim 17 A method for inhibiting the corrosion of a ferrous metal in contact with a metal-corrosive aqueous system, the method comprising the steps of: a) adding to the metal corrosive aqueous system from about 50 to about 600 ppm of cyanuric acid; and b) adding to the metal corrosive aqueous system from about 3 to about 50 ppm of at least one water-soluble salt selected from the group consisting of alkali metal molybdate salts, alkali metal silicate salts, and mixtures therof. ### Claim 18 (depends on 17) The method claim 17, further comprising the step of: c) adding to the metal corrosive aqueous system from about 300 to about 2000 ppm of sodium bromide. ### Claim 19 (depends on 17) The method of claim 17 wherein step b) comprises: i) adding to the metal corrosive aqueous system from about 3 to about 50 ppm of sodium molybdate; and ii) adding to the metal corrosive aqueous system from about 5 to about 50 ppm of sodium silicate. ### Claim 20 (depends on 17) The method of claim 17 further comprising the step of: d) adding to the metal corrosive aqueous system a substance selected from the group consisting of sodium carbonate, polyacrylate homopolymer, and 2-phosphonobutane-1,2,4-tricarboxylic acid.