The disclosed technology relates to methods of inhibiting corrosion in reaction chambers configured for hydrothermal reaction of feeds containing a heteroatom. An embodiment of such a method comprises providing a feed stream comprising a phosphorus-containing material, an alkali metal compound, water, and a corrosion-inhibitor. The embodiment additionally includes introducing the feed stream and oxidant into a reactor chamber and oxidizing the phosphorus-containing material at an oxidation temperature greater than about 374 C. and an oxidation pressure exceeding about 25 bar, wherein the reactor chamber has inner surfaces comprising a material that corrodes when in contact with a phosphorus compound within the reactor. The embodiment additionally includes selectively reacting the corrosion-inhibitor with phosphorus within the reactor, thereby precipitating in the reactor chamber a phosphorus-containing solid inorganic compound. The embodiment further includes forming in the reactor chamber an alkali salt melt and carrying away from the reactor chamber a mixture comprising the solid phosphorus-containing inorganic compound and the alkali salt melt.

The disclosed technology relates to methods of inhibiting corrosion in reaction chambers configured for hydrothermal reaction of feeds containing a heteroatom. An embodiment of such a method comprises providing a feed stream comprising a phosphorus-containing material, an alkali metal compound, water, and a corrosion-inhibitor. The embodiment additionally includes introducing the feed stream and oxidant into a reactor chamber and oxidizing the phosphorus-containing material at an oxidation temperature greater than about 374 C. and an oxidation pressure exceeding about 25 bar, wherein the reactor chamber has inner surfaces comprising a material that corrodes when in contact with a phosphorus compound within the reactor. The embodiment additionally includes selectively reacting the corrosion-inhibitor with phosphorus within the reactor, thereby precipitating in the reactor chamber a phosphorus-containing solid inorganic compound. The embodiment further includes forming in the reactor chamber an alkali salt melt and carrying away from the reactor chamber a mixture comprising the solid phosphorus-containing inorganic compound and the alkali salt melt.

An additive comprising one or more C.sub.3-C.sub.12 hydroxycarboxylic acids and/or one or more C.sub.3-C.sub.12 hydroxycarboxylic acid salts may be added to an aqueous system having galvanized metallurgy or a carbon steel surface in an effective amount to passivate a galvanized coating on the metallurgy or to decrease white rust formation or other types of corrosion upon the galvanized metallurgy or carbon steel surface in an aqueous system. In a non-limiting embodiment, the C.sub.3-C.sub.12 hydroxycarboxylic acid or the C.sub.3-C.sub.12 hydroxycarboxylic acid salt additive may utilize the zinc in the galvanized coating to achieve passivation. The passivation may occur while the system is shut down or in service. The aqueous system may be or include a cooling tower, a cooling water system, and combinations thereof. The additive may be used with or in the absence of a phosphorous-containing compound.

An additive comprising one or more C.sub.3-C.sub.12 hydroxycarboxylic acids and/or one or more C.sub.3-C.sub.12 hydroxycarboxylic acid salts may be added to an aqueous system having galvanized metallurgy or a carbon steel surface in an effective amount to passivate a galvanized coating on the metallurgy or to decrease white rust formation or other types of corrosion upon the galvanized metallurgy or carbon steel surface in an aqueous system. In a non-limiting embodiment, the C.sub.3-C.sub.12 hydroxycarboxylic acid or the C.sub.3-C.sub.12 hydroxycarboxylic acid salt additive may utilize the zinc in the galvanized coating to achieve passivation. The passivation may occur while the system is shut down or in service. The aqueous system may be or include a cooling tower, a cooling water system, and combinations thereof. The additive may be used with or in the absence of a phosphorous-containing compound.

A corrosion inhibitor can include (a) an inorganic alkali and/or alkaline earth metal compound and (b) an aldehyde and/or ketone component comprising at least one aromatic ring comprising a ketone and/or aldehyde group and at least one pendant group represented by OR.sup.1. Each R.sup.1 is independently selected from hydrogen, an alkyl group, or an aryl group. The coating composition can be used in a multi-layer coating with additional coating layers. Methods of preparing coating compositions with corrosion inhibitors and substrates at least partially coating with such compositions are also included.

A corrosion inhibitor can include (a) an inorganic alkali and/or alkaline earth metal compound and (b) an aldehyde and/or ketone component comprising at least one aromatic ring comprising a ketone and/or aldehyde group and at least one pendant group represented by OR.sup.1. Each R.sup.1 is independently selected from hydrogen, an alkyl group, or an aryl group. The coating composition can be used in a multi-layer coating with additional coating layers. Methods of preparing coating compositions with corrosion inhibitors and substrates at least partially coating with such compositions are also included.

Disclosed is a corrosion inhibition coating, comprising: a base comprising a matrix and a metal within the matrix; and an inhibitor comprising: zinc molybdate, cerium citrate, magnesium metasilicate, a metal phosphate silicate, or a combination thereof, wherein the metal within the matrix comprises aluminum, an aluminum alloy, zinc, a zinc alloy, magnesium, a magnesium alloy, or a combination thereof. Also disclosed is a substrate coated with the corrosion inhibition coating.

A composition with corrosion inhibiting properties is provided that includes a first phosphate salt of at least one of trimetaphosphate, hexametaphosphate, or tripolyphosphate. A second phosphate salt of at least one of a disodium phosphate and tetrasodium pyrophosphate is also present with the first phosphate salt present in a weight ratio relative to the second phosphate salt of from 1-4:1. Upon dissolution from 0.1 to 5 total weight percent in a solvent a corrosion inhibiting solution results that is well suited for usage as a water conditioner in cooling systems. A process of protecting an iron containing metal from corrosion is also provided that includes exposing the metal to the solution. The corrosion of the metal over time is monitored to assure the protection of the metal.

Methods and systems for converting inactive chemicals into active chemicals in-situ for treating oil and gas pipelines, other industrial systems, or sanitizing surfaces. Also, methods of treating an oil and gas pipeline including feeding an inactive additive through a first conduit and into a second conduit, the second conduit is in fluid communication with the first conduit and the oil and gas pipeline. The inactive additive is converted into an active additive within the second conduit and introduced into the oil and gas pipeline.

A corrosion inhibitor can include (a) an inorganic alkali and/or alkaline earth metal compound and (b) an aldehyde and/or ketone component comprising at least one aromatic ring comprising a ketone and/or aldehyde group and at least one pendant group represented by OR.sup.1. Each R.sup.1 is independently selected from hydrogen, an alkyl group, or an aryl group. The coating composition can be used in a multi-layer coating with additional coating layers. Methods of preparing coating compositions with corrosion inhibitors and substrates at least partially coating with such compositions are also included.