Patent ID: 7407599
Filing Date: 2008-08-05
Classification: C09K,C23F

Abstract:
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.