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.

A thermally stable, solid sulfite-based treatment composition for treating water systems, particularly heated water systems, to reduce corrosion. A treatment composition comprises (1) a sulfite salt that may provide at least 50% weight active sulfite and (2) a second inorganic salt hydrate that may have a melting point of 45? C. or higher. The treatment composition does not physically degrade or experience melting when stored at temperatures of 35? C.-40? C. The treatment composition is made by mixing water and a sulfite salt at an elevated temperature, then adding a second inorganic salt while maintaining the elevated temperature until a homogenous mixture is formed, then pouring the mixture in a mold and allowing it to cure at room temperature. A preferred sulfite salt is sodium metabisulfite. A preferred second inorganic salt is dipotassium phosphate.

Compositions comprising thiol-terminated polythioether prepolymers, polyepoxides and non-chromate corrosion inhibitors suitable for use in aerospace sealant applications are disclosed. Sealants prepared using the compositions adhere to a variety of aerospace substrates following exposure to aerospace fluids.

The present invention relates to a water treatment composition comprising blended phosphates which exhibit a synergistic effect for corrosion and scale control and as a sequestering chemical treatment of potable water and more particularly to chemistry which lowers the phosphate concentration necessary to achieve effective corrosion prevention. The composition controls corrosion and cleans the water distribution line by removing scale, tuberculation, and biofilm. Sequestration of the heavy metals and soft metals such as iron, manganese, calcium, and magnesium provides complete solubility of the material to be removed from the metal surface. The inclusion of citric acid with the blended phosphate formula improves drinking water quality in 2 ways: 1) a reducing agent reverses the oxidation of metals which would convert metal to metal salts (copper/lead, etc.) and 2) by chelation, it encapsulates transition metal cations, especially Manganese and Iron, found while source water passes through the treatment process and the drinking water distribution piping network.

The invention provides methods and compositions for addressing the problem of microorganism infestations and especially biocorrosion in slurry transporting pipelines. The method comprises treating pipeline fluid (especially plug fluid) with an oxidizing biocide in an amount higher than the oxidant demand of the pipeline and a non-oxidizing biocide in an amount less than 30% of the minimum necessary to sterilize the microbiological organisms. This treatment makes use of the unique characteristics of a slurry pipeline to eliminate microorganisms without harming the pipeline as would be expected by using an oxidizing biocide.

Use of a composition (A) having a pH of at least 8 at 25 C. containing at least 50 wt.-% of water or a water containing solvent mixture, at least 0.1 mol/m3 of at least one water soluble silicate, optionally at least one molybdate, optionally at least one phosphonate, optionally at least one azole, optionally at least one additional freezing point depressing salt, optionally at least one phosphate, and optionally at least one nitrate, as heat carrier medium for magnetocaloric materials of formula (I) (A.sub.yB.sub.1y).sub.2+uC.sub.wD.sub.xE.sub.z (I) where: A is Mn or Co, B is Fe, Cr or Ni, C is Ge, As or Si, D is different from C and is selected from P, B, Se, Ge, Ga, Si, Sn, N, As and Sb, E may be same or different from C and D and is selected from P, B, Se, Ge, Ga, Si, Sn, N, As and Sb.

The present invention describes novel coolant concentrates and the production and use thereof.

The present invention describes novel coolant concentrates and the production and use thereof.

The present disclosure provides an aqueous binder composition for forming a sacrificial corrosion-protective coating, said composition being free of chromates and also preferably free of borates and molybdates. Said binder composition advantageously has a pH of less than 6 and comprises a binder, particles of at least one metal oxide and at least one metallic phosphate, said binder comprising a hydrolyzed organosilane oligomer. In addition, the proportion by weight of said particles of at least one metal oxide relative to the total dry weight of said binder composition is greater than or equal to 75%.

The present disclosure provides an aqueous binder composition for forming a sacrificial corrosion-protective coating, said composition being free of chromates and also preferably free of borates and molybdates. Said binder composition advantageously has a pH of less than 6 and comprises a binder, particles of at least one metal oxide and at least one metallic phosphate, said binder comprising a hydrolyzed organosilane oligomer. In addition, the proportion by weight of said particles of at least one metal oxide relative to the total dry weight of said binder composition is greater than or equal to 75%.