Heat transfer fluid concentrates include: a freezing point depressant, water, or a combination thereof; an organophosphate; a carboxylic acid or a salt thereof; and a component selected from the group consisting of an alkaline earth metal ion, an alkali metal ion, a transition metal ion, an inorganic phosphate, molybdate ion, nitrate ion, nitrite ion, an azole compound, a copper and copper alloy corrosion inhibitor, a silicate, a silicate stabilizer, a water-soluble polymer, and combinations thereof. Ready-to-use heat transfer fluids and methods for preventing corrosion in heat transfer systems are described.

Inhibiting or preventing corrosion of metallic components downhole may be accomplished by introducing neutralization media into a wellbore in the proximity of downhole metallic components, where the neutralization media comprises magnesium and where the method further includes subsequently contacting the neutralization media with a potentially corrosive environment comprising at least 5 volume % water, where the water has a pH of less than 11. This contacting activates the neutralization media with the water thereby releasing magnesium ions, and the magnesium ions react with hydroxyl ions of the water to give magnesium hydroxide in an amount effective to raise the pH of the water present to be between about 8 and 12 thereby inhibiting or preventing corrosion of metallic components downhole.

A method of making cerium citrate includes combining cerium carbonate and citric acid to produce cerium citrate and carbon dioxide. The cerium citrate is substantially free of negative ions other than citrate. The cerium citrate can be used in a corrosion inhibitor composition.

Inhibiting or preventing corrosion of metallic components downhole may be accomplished by introducing neutralization media into a wellbore in the proximity of downhole metallic components, where the neutralization media comprises magnesium and where the method further includes subsequently contacting the neutralization media with a potentially corrosive environment comprising at least 5 volume % water, where the water has a pH of less than 11. This contacting activates the neutralization media with the water thereby releasing magnesium ions, and the magnesium ions react with hydroxyl ions of the water to give magnesium hydroxide in an amount effective to raise the pH of the water present to be between about 8 and 12 thereby inhibiting or preventing corrosion of metallic components downhole.

A system includes a turbine combustor and one or more supply circuits configured to supply one or more fluids to the turbine combustor. The one or more supply circuits include at least a liquid fuel supply circuit fluidly coupled to a liquid fuel source and configured to supply a liquid fuel from the liquid fuel source to the turbine combustor. The system also includes a corrosion inhibitor injection system including a magnesium source storing a magnesium-based inhibitor that includes magnesium oxide (MgO) and an yttrium source storing an yttrium-based inhibitor that includes yttrium oxide (Y.sub.2O.sub.3). The corrosion inhibitor injection system is fluidly coupled to the turbine combustor and the one or more supply circuits, and is configured to inject the magnesium-based inhibitor and the yttrium-based inhibitor as vanadium corrosion inhibitors into the turbine combustor or the one or more supply circuits.

Described herein are pretreatment compositions, coated aluminum alloy products, and methods for coating the alloys. The pretreatment compositions include inorganic chemical corrosion inhibitors dispersed in a silane-based matrix and may further include clay particles. The inorganic chemical corrosion inhibitors include rare earth metals and salts thereof. The pretreatment compositions, when applied to the surface of an alloy, inhibit corrosion of the alloys. The pretreatment compositions can be used in automotive, electronics, industrial, transportation, and other applications.

A process based on the combined use of yttrium and magnesium to inhibit vanadium corrosion of high temperature parts of thermal equipment. The combined use of yttrium and magnesium, applied in a variable yttrium/magnesium ratio, compared with conventional magnesium inhibition, may reduce emission of magnesium vanadate and minimize losses of performance due to fouling of the high temperature parts, including in the presence of alkali metals. Further, compared with inhibition based on yttrium alone, it may reduce the inhibition cost and reinforce the protection against combined vanadium pentoxide and sodium sulfate corrosion.

A method of making cerium citrate includes combining cerium carbonate and citric acid to produce cerium citrate and carbon dioxide. The cerium citrate is substantially free of negative ions other than citrate. The cerium citrate can be used in a corrosion inhibitor composition.

A corrosion resistant article including an aluminum substrate and a corrosion-inhibiting cerium based corrosion inhibitor corrosion inhibiting additive on the aluminum substrate, the corrosion inhibiting additive comprising an anodic corrosion inhibitor and a cathodic corrosion inhibitor, the anodic corrosion inhibitor greater than 25 wt % of the total inhibitor.

The invention relates to compositions, methods and preparation of such compositions to protect metals from corrosion, especially acid corrosion. The compositions of this invention may be added to acids to protect metals from their corrosive influence, particularly at elevated temperatures. These compositions are of particular utility in the oil and gas (petroleum) industry. Also disclosed are corrosion inhibition intensifiers to enhance the corrosion inhibition properties of other corrosion inhibitors. Formulations which control ferric ions in acidic solutions are also disclosed. These may be combined with inhibited acids and some compositions provide both corrosion inhibition and ferric ion control.