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US 10,246,622 B2Granted
Coolant having rapid metal passivation properties
AssigneeArteco NV
InventorsSandra G. Claeys, Serge S. Lievens
Life of this patent
Estimating the term…
Abstract
It has been found that the chemical reactivity of the metal surface of heat exchangers with coolants in presence of nitrites can be reduced by the addition of additives such as phosphonates or phosphinates. Aluminum, other Group III metals, as well as other metals commonly used in cooling systems, such as those of automobile engines, may thus be effectively protected.
Claims22
A heat transfer solution which provides passivation when placed in contact with metal surfaces, said solution comprising:
- (a) water, an alcohol, or a mixture of both;
- (b) from 0.01 to 1 wt % of a nitrite;
- (c) from 0.0001 to 1 wt % of a phosphonate or a phosphinate,
- the phosphonate having the formula R—[CR2]m—PO3M2 wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion;
- the phosphinate having the formula R—[CR2]m—P(O2M)H wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphino group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion;
- (d) an alkaline earth metal compound;
- and
- (e) a corrosion inhibitor selected from the group consisting of 2-ethylhexanoic acid, sebacic acid, and mixtures thereof,
- wherein the heat transfer solution is free of inorganic phosphates.
6 more elements
A process for passivation of metal surfaces, wherein the surfaces are treated with a solution comprising:
- (a) a liquid selected from the group consisting of water, an alcohol, and mixtures thereof;
- (b) from 0.01 to 1 wt % of a nitrite;
- (c) from 0.0001 to 1 wt % of:
- a phosphonate having the formula R—[CR2]m—PO3M2 wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion;
- or a phosphinate having the formula R—[CR2]m—P(O2M)H wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphino group, carbonyl compound, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion;
- (d) an alkaline earth metal compound;
- and (e) and a corrosion inhibitor selected from the group consisting of 2-ethylhexanoic acid, sebacic acid, and mixtures thereof, wherein the solution is free of inorganic phosphates.
4 more elements
A heat transfer solution which provides passivation when placed in contact with metal surfaces, said solution comprising:
- (a) water, an alcohol, or a mixture of both;
- (b) from 0.01 to 1 wt % of a nitrite;
- (c) from 0.0001 to 1 wt % of a phosphonate having the formula R—[CR2]m—PO3M2 wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion;
- or a phosphinate having the formula R—[CR2]m—P(O2M)H wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphino group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion;
- (d) an alkaline earth metal compound;
- and
- (e) a corrosion inhibitor,
- wherein the heat transfer solution is free of inorganic phosphates.
5 more elements
A heat transfer solution which provides passivation when placed in contact with metal surfaces, said solution comprising:
- (a) water, an alcohol, or a mixture of both;
- (b) from 0.01 to 1 wt % of a nitrite;
- (c) from 0.0001 to 1 wt % of a phosphonate having the formula R—[CR2]m—PO3M2 wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion;
- or a phosphinate having the formula R—[CR2]m—P(O2M)H wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphino group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion;
- (d) an alkaline earth metal compound;
- and
- (e) a corrosion inhibitor selected from the group consisting of 2-ethylhexanoic acid, sebacic acid, and mixtures thereof.
4 more elements
Dependencies are inferred from the claim text.