Cooling system cleaning composition
AssigneeUnion Carbide Corporation
InventorAlan G. Barber
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Abstract
A cooling system cleaning composition comprising an aqueous solution of a tetra-alkali metal salt of ethylenediaminetetraacetic acid, a soluble salt of citric acid, and a soluble salt of nitric acid. The preferred composition also contains an aluminum corrosion inhibitor and has a pH between about 10 and about 14.
Claims32
A cooling system cleaning composition comprising an aqueous solution of between about 0.3 and about 15 weight percent of a tetra-alkali metal salt of ethylenediaminetetraacetic acid, between about 0.6 and about 35 weight percent of a water-soluble salt of citric acid and between about 0.2 and about 20 weight percent of a water-soluble salt of nitric acid, said weight percentages based on the sodium salts and said composition being effective for removing solder bloom.
A cooling system cleaning concentrate comprising an aqueous solution of between 3 and about 15 weight percent of tetrasodium ethylenediaminetetraacetic acid, of between about 5 and about 35 weight percent trisodium citrate dihydrate, and of between about 2 and about 20 weight percent sodium nitrate, based on the total weight of the composition, said concentrate being effective for removing solder bloom when diluted with water at a ratio between about 0:1 and about 10:1 volumes water to volumes concentrate.
A method for cleaning solder bloom from a cooling system which comprises (a) removing any antifreeze coolant from the cooling system;
- (b) adding to the cooling system an aqueous solution of a tetra-alkali-metal salt of ethylenediaminetetraacetic acid, of a soluble salt of citric acid, and of a soluble salt of nitric acid;
- (c) circulating the aqueous solution through the cooling system to remove the solder bloom from the metal surfaces of the cooling system;
- and (d) removing from the cooling system the aqueous solution and the solder bloom removed from the metal surfaces.
Dependencies are inferred from the claim text.