# US 7,407,599 B2 · Acid based antifreeze composition > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,407,599 B2 - Document ID: US7407599B2 - Status: Granted - Kind: B2 - Application number: 10/755,713 - Filed: 2004-01-12 - Published: 2004-11-18 - Granted: 2008-08-05 - Earliest claimed: 2001-05-08 - Assignees: Ashland Licensingaand Intellectual Property, LLC - Inventors: David E. Turcotte; Michael Dituro; Alden W. Olsen; Arnold L. Coffey, Jr.; Carl R. Stephens - Web page: https://patentgrep.com/patent/US7407599B2 ## CPC - C23F 11/08: in other liquids - C09K 5/20: Antifreeze additives therefor, e.g. for radiator liquids (for application to surfaces C09K3/18; inhibiting corrosion by liquids C23F11/00) - 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 - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract The present invention relates to a carboxylic acid based antifreeze coolant formulation for heavy duty applications such as for diesel engines which may be used for inhibition and prevention erosion and corrosion of aluminum and the corrosion of other metals exposed to an aqueous liquid in automotive coolant systems. The formulation further inhibits mineral scale. It may be packaged as an ethylene glycol based additive for use in new engines or in a concentrated inhibition package as an additive as for reinhibition of used coolant. The combination of a mixture of ethylene or propylene glycol, a monobasic carboxylic organic acid, azoles, low levels of molybdates, a nitrite salt and/or nitrate salt and/or siloxane stabilized silicate, and combinations thereof, polyvinylpyrrolidone, provide a synergistic protective effect against the cavitation corrosion of aluminum in aqueous liquids reducing the corrosion rate and is effective at relatively low concentrations and varying pH ranges. ## Claims ### Claim 1 An acid based antifreeze composition for inhibiting the corrosion of metals and inhibiting mineral scale based on 100 parts by weight of said glycol-based solution consisting of a monobasic carboxylic acid of up to 10.0 weight percent, a nitrite salt which is at least one selected from the group consisting of sodium nitrite, potassium nitrite, magnesium nitrite, calcium nitrite, lithium nitrite and combinations thereof in an amount of from 0.001 to about 10.0 percent by weight, a nitrate salt selected from the group consisting of sodium nitrate, potassium nitrate, magnesium nitrate, calcium nitrate, lithium nitrate, and combinations thereof in an amount of from 0.001 to about 10.0 percent by weight, an azole compound selected from the group consisting of sodium mercaptobenzothiazole, sodium tolytriazole, water-soluble triazoles, benzotriazole, tolyltriazole, sodium 2-mercaptobenzothiazole and combinations thereof in an amount of about 0.01 to about 10.0 percent by weight, a silicone-silicate copolymer in an amount of about 0.01 to about 10.0 percent by weight, from about 0.001 to about 5.0 percent by weight of a polyvinylpyrrolidone, from about 0.001 to about 10.0 weight percent of a transition metal compound selected from the group consisting of disodium salt dihydrate of molybdic acid, molybdenum trioxide, silicoheteropolymolybdates and/or phosphoroheteropolymolybdates, sodium molybdate, potassium molybdate, lithium molybdate, ammonium molybdate, ammonium dimolybdate, and ammonium heptamolybdate, and a glycol compound selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and combinations thereof making up the balance of the solution further consisting of: an antifreeze/coolant reinhibition concentrate packaged as an additive added at a rate of one (1) part to approximately fifty (50) parts of spent diluted, coolant, consisting of: a. a major amount of a water soluble liquid alcohol freezing point depressant in an amount of from about 80 to about 90 percent by weight; b. a salt selected from the group consisting of sodium nitrite, potassium nitrite, magnesium nitrite, calcium nitrite, lithium nitrite, sodium nitrate, potassium nitrate, magnesium nitrate, calcium nitrate, lithium nitrate, and combinations thereof in an amount of about 0.001 to about 10.0 percent by weight; c. an azole compound comprising at least three nitrogen molecules in an amount of about 0.01 to about 10.0 percent by weight; d. a silicone-silicate copolymer in an amount of from 0.01 to 10.0 percent by weight; and e. a polyvinylpyrrolidone in an among of from about 0.001 to about 5.0 percent by weight. ### Claim 2 (depends on 1) The reinhibition concentrate of claim 1, wherein said major amount of a water soluble liquid alcohol freezing point depressant is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, methyl alcohol, ethyl alcohol, propyl alcohol, and isopropyl alcohol, and combinations thereof. ### Claim 3 (depends on 1) The reinhibition concentrate of claim 1, wherein said azole compound is selected from the group consisting of tolytriazole, hydrocarbyl triazole, benzotriazole, mercaptobenzothizole, pyrazoles, isooxazoles, isothiazoles, thiazoles, thiadiazole salts, 1,2,3-benzotriazole, 1,2,3-tolyltriazole, sodium 2-mercaptobenzothiazole, a three ring nitrogen containing azole, and combinations thereof. ### Claim 4 (depends on 1) The reinhibition concentrate of claim 1, wherein said azole compound is present in an amount of from between about 0.01 to about 5.0 weight percent. ### Claim 5 (depends on 1) The reinhibition concentrate of claim 1, wherein said silicone-silicate copolymer present in an amount of about 0.01 to about 5.0 percent by weight. ### Claim 6 (depends on 1) The reinhibition concentrate of claim 1, wherein said polyvinylpyrrolidone is present in an amount of from about 0.001 to about 3.0 percent by weight. ### Claim 7 An antifreeze/coolant reinhibition concentrate for inhibiting the corrosion of metals and inhibiting mineral scale based on 100 parts by weight of a glycol-based solution for addition at a rate of 1 part to 50 parts to spent diluted coolant consisting of a major amount of spent diluted coolant and a reinhibition concentrate consisting of: a) a salt which is at least one selected from the group consisting of sodium nitrite, potassium nitrite, magnesium nitrite, calcium nitrite, lithium nitrite and combinations thereof in an amount of from 0.001 to about 10.0 percent by weight; b) an azole compound selected from the group consisting of 50% sodium mercaptobenzothiazole, 50% sodium tolytriazole, 50% benzotriazole, and combinations thereof in an amount of 0.01 to 5.0 percent by weight; c) a silicone-silicate copolymer in an amount of about 0.01 to about 10.0 percent by weight,; d) from about 0.001 to about 5.0 percent by weight of a polyvinylpyrrolidone; and e) the balance comprising a glycol compound comprising an ethylene glycol, diethylene glycol, propylene glycol, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and combinations thereof making up the balance of the solution. ### Claim 8 (depends on 7) The acid based antifreeze composition of claim 7, wherein said azole compound is present in an amount of about 4 weight percent. ### Claim 9 (depends on 7) The acid based antifreeze composition of claim 7, wherein said salt is present in an effective amount of about 5 percent by weight. ### Claim 10 (depends on 7) The acid based antifreeze composition of claim 7, wherein said stabilized silicone-silicate is present in an effective amount of about 4 percent by weight. ### Claim 11 (depends on 7) The acid based antifreeze composition of claim 7, wherein said polyvinylpyrrolidone is present in an effective amount of about 1 percent. ### Claim 12 (depends on 7) The acid based antifreeze composition of claim 7, wherein said glycol compound is present in an amount of about 86 percent. ### Claim 13 An antifreeze/coolant reinhibition concentrate for inhibiting the corrosion of metals and inhibiting mineral scale based on 100 parts by weight of a glycol-based solution, for addition at a rate of 1 part to 50 parts to spent diluted coolant consisting of a major amount of spent diluted coolant and a reinhibition concentrate consisting of: a) a salt which is at least one selected from the group consisting of sodium nitrite, potassium nitrite, magnesium nitrite, calcium nitrite, lithium nitrite and combinations thereof in an amount of about 5 percent by weight; b) an azole compound selected from the group consisting of 50% sodium mercaptobenzothiazole, 50% sodium tolytriazole, 50% benzotriazole, and combinations thereof in an amount of about 4 percent by weight; c) a silicone-silicate copolymer in an amount of about 4 percent by weight; d) a polyvinylpyrrolidone in an amount of about 1 percent by weight of; and e) the balance comprising a glycol compound comprising an ethylene glycol, diethylene glycol, propylene glycol, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and combinations thereof in an amount of about 86 percent by weight. ### Claim 14 An antifreeze/coolant reinhibition concentrate for inhibiting the corrosion of metals and inhibiting mineral scale based on 100 parts by weight of a glycol-based solution, for addition at a rate of 1 part to 50 parts to spent diluted coolant consisting of a major amount of spent diluted coolant and a reinhibition concentrate consisting of: a) a salt which is at least one selected from the group consisting of sodium nitrite, potassium nitrite, magnesium nitrite, calcium nitrite, lithium nitrite and combinations thereof in an amount of from 0.001 to about 10.0 percent by weight; b) an azole compound having at least three nitrogen molecules in an amount of 0.01 to 5.0 percent by weight; c) a silicone-silicate copolymer in an amount of about 0.01 to about 10.0 percent by weight,; d) from about 0.001 to about 5.0 percent by weight of a polyvinylpyrrolidone; and e) the balance comprising a major amount of a glycol compound comprising an ethylene glycol, diethylene glycol, propylene glycol, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and combinations thereof making up the balance of the solution. ### Claim 15 (depends on 14) The antifreeze/coolant reinhibition concentrate of claim 14, wherein said azole compound is selected from the group consisting of 50% sodium mercaptobenzothiazole, 50% sodium tolytriazole, 50% benzotriazole, and combinations thereof. ### Claim 16 (depends on 14) The acid based antifreeze composition of claim 14, wherein said azole compound is present in an amount of about 4 weight percent. ### Claim 17 (depends on 14) The acid based antifreeze composition of claim 14, wherein said salt is present in an effective amount of about 5 percent by weight. ### Claim 18 (depends on 14) The acid based antifreeze composition of claim 14, wherein said stabilized silicone-silicate is present in an effective amount of about 4 percent by weight. ### Claim 19 (depends on 14) The acid based antifreeze composition of claim 14, wherein said polyvinylpyrrolidone is present in an effective amount of about 1 percent. ### Claim 20 (depends on 7) The acid based antifreeze composition of claim 7, wherein said glycol compound is present in an amount of about 86 percent. ### Claim 21 An antifreeze/coolant reinhibition concentrate for inhibiting the corrosion of metals and inhibiting mineral scale based on 100 parts by weight of a glycol-based solution, for addition at a rate of 1 part to 50 parts to spent diluted coolant consisting of a major amount of spent diluted coolant and a reinhibition concentrate consisting of: a) a salt which is at least one selected from the group consisting of sodium nitrite, potassium nitrite, magnesium nitrite, calcium nitrite, lithium nitrite and combinations thereof in an amount of about 5 percent by weight; b) b) an azole compound having at least three nitrogen molecules in an amount of about 4 percent by weight; c) a silicone-silicate copolymer in an amount of about 4 percent by weight,; d) a polyvinylpyrrolidone in an amount of about 1 percent by weight of; and e) the balance comprising a glycol compound comprising an ethylene glycol, diethylene glycol, propylene glycol, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and combinations thereof in an amount of about 86 percent by weight. ### Claim 22 (depends on 21) The acid based antifreeze composition of claim 21, wherein said azole azole compound is selected from the group consisting of 50% sodium mercaptobenzothiazole, 50% sodium tolytriazole, 50% benzotriazole, and combinations thereof.