Corrosion inhibitor salts

Failure of sensitive filtration tests such as ASTM D-2276, Particulate Contamination in Aviation Fuel by Line Sampling, can be due to caustic neutralized corrosion inhibitor salts. Sodium or calcium salts of dimer-trimer fatty acid corrosion inhibitors are gel-like in character. Filtration of jet fuel containing gelled corrosion inhibitor will be impeded due to plugging of fuel filter media by the inhibitor gel. This slowdown of filtration can result in failure of jet fuel to pass this critical performance test. 

Test method ASTM D-2276, Particulate Contaminant in Aviation Fuel by Line Sampling, requires filtration of fuel through a 0.8-micron filter. Caustic neutralized corrosion inhibitor salts can block these filters and slow down the filtration of fuel enough to cause failure of this ASTM test. 

Sodium or calcium salt of carboxylic acid in deposit Indicates the presence of corrosion inhibitor salt... 

Properties Soft solid m.w. 366.63 cationic Toxicology TSCA listed Uses 0/w emulsifier, antistat, emollient, conditioner, substantivity agent, lubricant, moisturizer in cosmetics intermediate for cationic surfactants, chemical specialties, hair conditioners, mild cleansers corrosion inhibitor salts as emulsifier for acid systems Trade Name Synonyms Chemidex O [Chemron http //www.chemron.com, Costec http //www.costec.com]-, Incromine OPB [Croda Inc http //www.croda.com], Incromine 0PM t[Croda Inc http //www.croda.com], Lexamine 0-13 t[lnolex http //www.inolex.com]-, Mackine 501 [M cl ntyre http //www.mcintyregroup. com] Schercodine O [Scher... 

Uses Surfactant in cosmetics hair conditioner intermediate for cationic surfactants, chemical specialties corrosion inhibitor salts as emulsifier for acid systems Trade Name Synonyms Mackine 701 [McIntyre http.V/www.mcintyregroup. com] Wheatgermamidopropyl dimethylamine hydrolyzed wheat protein Definition Wheatgermamidopropyl dimethylamine sait of hydroiyzed wheat protein Uses Antistat in cosmetics hair and skin conditioner... 

Uses Intermediate for cationic surfactants, chemical specialties, hair conditioners, mild cleansers corrosion Inhibitor salts as emulsifier for add systems Properties Llq. 100% act. 

AH corrosion inhibitors in use as of this writing are oil-soluble surfactants (qv) which consist of a hydrophobic hydrocarbon backbone and a hydrophilic functional group. Oil-soluble surfactant-type additives were first used in 1946 by the Sinclair Oil Co. (38). Most corrosion inhibitors are carboxyhc acids (qv), amines, or amine salts (39), depending on the types of water bottoms encountered in the whole distribution system. The wrong choice of inhibitors can lead to unwanted reactions. Eor instance, use of an acidic corrosion inhibitor when the water bottoms are caustic can result in the formation of insoluble salts that can plug filters in the distribution system or in customers vehicles. Because these additives form a strongly adsorbed impervious film at the metal Hquid interface, low Hquid concentrations are usually adequate. Concentrations typically range up to 5 ppm. In many situations, pipeline companies add their own corrosion inhibitors on top of that added by refiners. 

Amine salts, especially acetate salts prepared by neutralization of a fatty amine with acetic acid, are useflil as flotation agents (collectors), corrosion inhibitors, and lubricants (3,8). Amine acetates are commercially available from a number of suppHers Akzo Chemicals Inc. (Armac) (73) Henkel Corporation (formerly General Mills) (Alamac) (74) Jetco Chemicals Inc. (The Procter Gamble Company) (fet Amine) (75) Sherex (Adogen) (76) and Tom ah Products (Exxon Chemical Company) (Tomah) (77). 

Its chief use is as a component in photographic developers. Because the free compound is unstable in air and light, it is usually marketed as the sulfate salt [55-55-0] Metol, mp 260°C (dec.). It also finds appHcation as an intermediate for fur and hair dyes and, under certain circumstances, as a corrosion inhibitor for steel. Prolonged exposure to 4-(/V-methy1amino)pheno1 has been associated with the development of dermatitis and allergies. 

Table 8 summarizes domestic consumption by use for amyl alcohols. About 55% of the total 1-pentanol and 2-methyl-1-butanol production is used for zinc diamyldithiophosphate lubrication oil additives (150) as important corrosion inhibitors and antiwear additives. Amyl xanthate salts are useful as frothers in the flotation of metal ores because of their low water solubiUty and miscibility with phenoHcs and natural oils. Potassium amyl xanthate, a collector in flotation of copper, lead, and zinc ores, is no longer produced in the United States, but imports from Germany and Yugoslavia were 910 —1100 t in 1989 (150). 

Petroleum sulfonates are widely used as solubilizers, dispersants (qv), emulsifiers, and corrosion inhibitors (see Corrosion and corrosion inhibitors). More recentiy, they have emerged as the principal surfactant associated with expanding operations in enhanced oil recovery (66). Alkaline-earth salts of petroleum sulfonates are used in large volumes as additives in lubricating fluids for sludge dispersion, detergency, corrosion inhibition, and micellar solubilization of water. The chemistry and properties of petroleum sulfonates have been described (67,68). Principal U.S. manufacturers include Exxon and Shell, which produce natural petroleum sulfonates, and Pilot, which produces synthetics. 

Corrosion Resistance. Titanium is immune to corrosion in all naturally occurring environments. It does not corrode in air, even if polluted or moist with ocean spray. It does not corrode in soil and even the deep salt-mine-type environments where nuclear waste might be buried. It does not corrode in any naturally occurring water and most industrial wastewater streams. For these reasons, titanium has been termed the metal for the earth, and 20—30% of consumption is used in corrosion-resistance appHcations (see Corrosion and corrosion inhibitors). 

The presence of ammonia during hydrogenation suppresses formation of secondary amines and inhibits hydrogenation of double bonds in unsaturated nitriles. Eatty amines are used as corrosion inhibitors, flotation agents, quaternary salts for sanitizing agents and textile fabric softeners, and surface-active agents. 

Corrosion inhibitors are substances which slow down or prevent corrosion when added to an environment in which a metal usually corrodes. Corrosion inhibitors are usually added to a system in small amounts either continuously or intermittently. The effectiveness of corrosion inhibitors is partiy dependent on the metals or alloys to be protected as well as the severity of the environment. For example, the main factors which must be considered before apphcation of a corrosion inhibitor to an aqueous system are the compatibility of the inhibitor and the metal(s), the salt concentration, the pH, the dissolved oxygen concentration, and the concentration of interfering species such as chlorides or metal cations. In addition, many inhibitors, most notably chromates, are toxic and environmental regulations limit use. Attention is now being given to the development of more environmentally compatible inhibitors (37). 

Although much weaker than the parent compound isocyanic acid (pK = 3.7), CA is sufftciendy acidic to form salts. Many inorganic and organic salts of CA have been reported (11). Lead and 2iuc cyanurates are usehil as corrosion inhibitors (20). The 1 1 adduct, melamine cyanurate [37640-57-6] has achieved commercial importance. 

Miscellaneous Derivatives. Fimehc acid is used as an intermediate in some pharmaceuticals and in aroma chemicals ethylene brassylate is a synthetic musk (114). Salts of the diacids have shown utUity as surfactants and as corrosion inhibitors. The alkaline, ammonium, or organoamine salts of glutaric acid (115) or C-5—C-16 diacids (116) are useflil as noncorrosive components for antifreeze formulations, as are methylene azelaic acid and its alkah metal salt (117). Salts derived from C-21 diacids are used primarily as surfactants and find apphcation in detergents, fabric softeners, metal working fluids, and lubricants (118). The salts of the unsaturated C-20 diacid also exhibit anticorrosion properties, and the sodium salts of the branched C-20 diacids have the abUity to complex heavy metals from dilute aqueous solutions (88). 

Foaming is usually caused by contamination of glycol with salt, hydrocarbons, dust, mud, and corrosion inhibitors. Remove the source of contamination with effective gas cleaning ahead of the absorber, improved solids filtration, and carbon purification. 

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