Corrosion protection compounds

Recovery of Ammonia. The filter Hquor contains unreacted sodium chloride and substantially all the ammonia with which the brine was originally saturated. The ammonia may be fixed or free. Fixed ammonia (ammonium chloride [12125-02-97]) corresponds stoichiometrically to the precipitated sodium bicarbonate. Free ammonia includes salts such as ammonium hydroxide, bicarbonate, and carbonate, and the several possible carbon—ammonia compounds that decompose at moderate temperatures. A sulfide solution may be added to the filter Hquor for corrosion protection. The sulfide is distilled for eventual absorption by the brine in the absorber. As the filter Hquor enters the distiller, it is preheated by indirect contact with departing gases. The warmed Hquor enters the main coke, tile, or bubble cap-fiUed sections of the distiller where heat decomposes the free ammonium compounds and steam strips the ammonia and carbon dioxide from the solution. 

Metal Finishing and Corrosion Control. The exceptional corrosion protection provided by electroplated chromium and the protective film created by applying chromium surface conversion techniques to many active metals, has made chromium compounds valuable to the metal finishing industry. Cr(VI) compounds have dominated the formulas employed for electroplating (qv) and surface conversion, but the use of Cr(III) compounds is growing in both areas because of the health and safety problems associated with hexavalent chromium and the low toxicity of trivalent chromium (see... 

A range of acetoacetylated lesins has been intioduced (68,69). The acetoacetoxy functionahty can be cioss-linked with melamine—formaldehyde resins, isocyanates, polyacrylates, and polyamines. There is particular interest for possible corrosion protection on steel because the acetoacetoxy group can form coordination compounds (qv) with iron, perhaps enhancing the adhesion to steel surfaces (see Chelating agents). 

Phosphorus and compounds SPA Phosphoric acid Boiler blowdown Corrosion protection Detergents Fertilizers Matches Metal finishing... 

The U.S. accounts for almost one-quarter of worldwide slab zinc consumption and is the world s single largest market. About 80% of zinc is used in metal form, and the rest is used in compound form. In total, 90% of zinc metal is used for galvanizing steel (a form of corrosion protection) and for alloys, and is used in a wide variety of materials in the automotive, construction, electrical, and machinery sectors of the economy. Zinc compound use also varies widely, but is mainly found in the agricultural, chemical, paint, pharmaceutical, and rubber sectors of the economy. 

See also Epoxy coatings Epoxy chalcone, 10 450 12,13-Epoxy-cis-9-octadecenoic (vernolic) acid, physical properties, 5 35t Epoxy coatings, 10 436 450 17 845. See also Epoxy can coatings for corrosion protection, 7 199 markets for, 10 442-449 performance of, 10 423 waterborne, 10 439 Epoxy composites, 10 450, 451 Epoxy compounds, photoinitiated polymerization of, 23 716 Epoxy content analysis, 10 385 Epoxy cresol novolac (ECN) resins, 10 367, 369... 

This problem is not common and is not expected. However, in a situation of gross overtreatment with an amine-based processing aid, interaction with a carboxylic acid based corrosion inhibitor is possible. In dilute solution within the fuel, it is unlikely that these compounds will react since only low levels, <5 ppm, of filmer or neutralizer will typically carry over into finished fuel. If the two do react, the product formed will provide corrosion protection, but not as effectively as the unreacted carboxylic acid based inhibitor. 

In hoi galvanizing, zinc is applied to iron and steel parts by immersing the parts into u butli of triollen zinc Whereas in principle almost any metal could be coaled with molten zinc, this coating serves no worthwhile purpose on most metals. The combination of zinc and ferrous materials are almost uniquely suited to each other. Aluminum and cadmium are the only other similar combinations, Zinc provides iron parts with better corrosion protection by developing a coating of zinc and zinc compounds on the base metal surface. 

Molybdenum salts used as catalysts include cobalt molybdate for hydrogen treatment of petroleum stocks for desulfurization, and phospho-molybdates to promote oxidation. Compounds used for dyes are sodium, potassium, and ammonium molybdates. With basic dyes, phosphomolyb-dic acid is employed. The pigment known as molybdenum orange is a mixed crystal of lead chromate and lead molybdate. Sodium molybdate, or molybdic oxide, is added to fertilizers as a beneficial trace element. Zinc and calcium molybdate serve as inhibitory pigments in protective coatings arid paint for metals subjected to a corrosive atmosphere. Compounds used to produce better adherence of enamels are molybdenum trioxide and ammonium, sodium, calcium, barium, and lead molybdates. 

The improvement of existing materials as well as the development of new materials is often based on the use of a chemical reaction in which a solid reacts with another solid, a liquid or a gas to form a solid product (an intermetallic, a silicide, an oxide, a salt, etc) at the interface between initial substances. Therefore, kinetics of solid-state formation of chemical compound layers are of interest not only to chemists (researchers and technologists) but also to metal and solid-state physicists, materials scientists, metallurgists, specialists in the field of corrosion, protective coating, welding, soldering and microelectronics. 

In addition to the organic compounds, waste water contains dissolved salts. This causes severe corrosion problems under conditions of operation in the near-critical region of water. The corrodibility of different materials in contact with waste water and oxidizing agents was investigated at temperatures up to 573 K and pressures up to 15 MPa. Furthermore, the applicability of appropriate inhibitors for corrosion protection was studied under mentioned conditions of wet oxidation. 

The complete elimination of heavy metals and other hazardous compounds from the coating systems was the main objective of SAIE. Chromated spray primers with hazardous chromate components do not fit such an objective. Therefore, two kinds of nonchromated and water-borne spray primers, Spraylat EWAE118 (D) and Dexter lO-PW-22-2 (X), were selected to produce chromate-free plasma coating systems for corrosion protection of A1 alloys. 

Tygon. TM for a series of vinyl compounds used as linings, coatings, adhesives, tubing, and extruded shapes applied to chemical process equipment as corrosion protection. 

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