Metal corrosion inhibition
A process is provided for inhibiting the corrosion of metal that comes into contact with a static or flowing aqueous medium which comprises contacting at least a portion of the exposed surface of the metal with aqueous medium containing a metal corrosion inhibiting amount of at least one ureido silane and, optionally, one or more added inorganic and/or other organic materials.
1. A process for inhibiting corrosion of a metal selected from the group consisting of brass, bronze, iron, steel, copper and aluminum that comes into contact with a static or flowing liquid aqueous medium, the process consisting of:
contacting at least a portion of an exposed surface of the metal with the liquid aqueous medium, wherein the liquid aqueous medium consists of:
(I) a water containing liquid, consisting of at least 20 weight percent water based on the weight of the water containing liquid, selected from the group consisting of an aqueous refrigerating solution, an acidified pickling solution, river water containing chlorides, carbonates and sulfates, corrosive well water, or a solution of water with at least one solute selected from the group consisting of, inorganic chlorides, inorganic carbonates, inorganic sulfates, water soluble liquid polyhydric alcohol, water soluble liquid hydroxyl end-blocked polyalkylene oxide, water soluble liquid alkoxy end-blocked polyalkylene oxide, water soluble liquid organic sulfoxide, water soluble liquid formamide and water soluble liquid cyclic ether free of olefinic unsaturation; and
(II) at least one ureido silane metal corrosion inhibitor, selected from the group consisting of gamma-ureidopropyltrimethoxysilane, gamma-ureidopropyltriethoxysilane, gamma-ureidopropyldimethoxyethoxysilane, gamma-ureidopropylmethoxydiethoxysilane, their hydrolyzates, their partial and/or substantially complete condensates and combinations of any of the foregoing, the metal corrosion inhibitor present in a metal corrosion inhibiting amount ranging from 1.1 to 5.1 weight percent based on the weight of the liquid aqueous medium, the metal corrosion inhibitor acting to inhibit corrosion of the metal; and
wherein the at least one ureido silane is uniformly dissolved in the liquid aqueous medium, the pH of the liquid aqueous medium is adjusted to a value of from 3 to 5 to inhibit the formation of a gel precipitate for a period for from 2 hours to 30 days and corrosion inhibition is provided for a period of from 2 hours to 30 days.
2. The process of claim 1 wherein the metal corrosion inhibitor consists of gamma-ureidopropyltrimethoxysilane, hydrolyzates of gamma-ureidopropyltrimethoxysilane, and partial or substantially complete condensates of gamma ureidopropyltrimethoxysilane and combinations of any of the foregoing.
3. The process of claim 1 wherein the metal is aluminum, copper or iron.
4. The process of claim 1 wherein at least 80 weight percent of the water containing liquid (I) consists of water.
5. The process of claim 1 wherein at least 99 weight percent of the water containing liquid (I) consists of water.
6. A corrosion-inhibited metal selected from the group consisting of brass, bronze, iron, steel, copper and aluminum having at least a portion of its exposed surface in contact with a static or flowing liquid aqueous medium, the liquid aqueous medium consisting of:
(I) a water containing liquid, consisting of at least 20 weight percent water based on the weight of the water containing liquid, selected from the group consisting of an aqueous refrigerating solution, an acidified pickling solution, river water containing chlorides, carbonates and sulfates, corrosive well water, or a solution of water with water soluble liquid polyhydric alcohol, water soluble liquid hydroxyl end-blocked polyalkylene oxide, water soluble liquid alkoxy end-blocked polyalkylene oxide, water soluble liquid organic sulfoxide, water soluble liquid formamide and water soluble liquid cyclic ether free of olefinic unsaturation; and
(II) a ureido silane metal corrosion inhibiting amount, ranging from 1.1 to 5.1 weight percent based on the weight of the liquid aqueous medium, of at least one ureido silane selected from the group consisting of gamma-ureidopropyltrimethoxysilane, gamma-ureidopropyltriethoxysilane, gamma-ureidopropyldimethoxyethoxysilane, gamma-ureidopropylmethoxydiethoxysilane, their hydrolyzates, their partial and/or substantially complete condensates and combinations of any of the foregoing; and
wherein the at least one ureido silane is uniformly dissolved in the liquid aqueous medium, and wherein the pH of the liquid aqueous medium is adjusted to a value of from 3 to 5 to inhibit the formation of a gel precipitate for a period for from 2 hours to 30 days and corrosion inhibition is provided for a period of from 2 hours to 30 days.
7. The corrosion-inhibited metal of claim 6 wherein the ureido silane is at least one member selected from the group consisting of gamma-ureidopropyltrimethoxysilane, hydrolyzates of gamma-ureidopropyltrimethoxysilane, partial or substantially complete condensates of gamma-ureidopropyltrimethoxysilane and combinations of any of the foregoing.
8. The corrosion-inhibited metal of claim 6 wherein the metal is aluminum, copper or iron.
9. The corrosion-inhibited metal of claim 6 , wherein at least 80 weight percent of the water containing liquid (I) consists of water.
10. The corrosion-inhibited metal of claim 6 wherein at least 99 weight percent of the water containing liquid (I) consists of water.
11. The corrosion-inhibited metal of claim 6 in contact with a static or flowing liquid aqueous medium, wherein the corrosion inhibited metal in contact with a static or flowing liquid aqueous medium is incorporated in an apparatus, equipment or device.
12. The corrosion-inhibited metal in contact with a static or flowing liquid aqueous medium of claim 11 wherein the apparatus, equipment or device is a boiler, heat exchanger, cooling tower, cooling jacket, radiator, chemical reactor, distillation column, thin film evaporator, crystallizer, ore treatment unit, settling tank, filtration apparatus, water treatment apparatus, ion exchange apparatus, decanter, spray tower, condenser, dehumidifier, metallized surface and/or circuitry used in semiconductor manufacture, pipeline, storage tank or washing equipment.