Naphtha corrosion

A high-nickel alloy is used for increased strength at elevated temperature, and a chromium content in excess of 20% is desired for corrosion resistance. An optimum composition to satisfy the interaction of stress, temperature, and corrosion has not been developed. The rate of corrosion is directly related to alloy composition, stress level, and environment. The corrosive atmosphere contains chloride salts, vanadium, sulfides, and particulate matter. Other combustion products, such as NO, CO, CO2, also contribute to the corrosion mechanism. The atmosphere changes with the type of fuel used. Fuels, such as natural gas, diesel 2, naphtha, butane, propane, methane, and fossil fuels, will produce different combustion products that affect the corrosion mechanism in different ways. 

Hydrofining has been applied to Varsols and various other solvents for the control of odor, sulfur, and corrosion characteristics. For example. Hydrofining of Iranian and Kuwait distillates demonstrated its effectiveness as a means of producing "White Spirit", a high-quality solvent naphtha distributed in the United Kingdom. 

T. M. McCullough. Emulsion minimizing corrosion inhibitor for naphtha/water systems. Patent US 5062992,1991. 

Yon-Hin, Paul. 1995. (Internal report) Naphtha copper corrosion. 95/474. Sugar Land, Tex. Nalco/Exxon Energy Chemicals, LP. 

Reprinted from Chloride Corrosion and Fouling in Catalytic Reformers with Naphtha Pretreaters, Corrosion, March 1961.)... 

Dissolved in naphtha, hydrogen chloride alone is not particularly corrosive the aluminum chloride slurry line and reactor feed line were of carbon steel. Carbon steel was also suitable for the hydrogen chloride stripper and absorber. 

An indication of naphtha composition may also be obtained from the determination of aniline point (ASTM D-1012, IP 2), freezing point (ASTM D-852, ASTM D-1015, ASTM D-1493) (Fig. 4.2), cloud point (ASTM D-2500) (Fig. 4.3), and solidification point (ASTM D-1493). And, although refinery treatment should ensure no alkalinity and acidity (ASTM D-847, ASTM D-1093, ASTM D-1613, ASTM D-2896, IP 1) and no olefins present, the relevant tests using bromine number (ASTM D-875, ASTM D-1159, IP 130), bromine index (ASTM D-2710), and flame ionization absorption (ASTM D-1319, IP 156) are necessary to ensure low levels (at the maximum) of hydrogen sulfide (ASTM D-853) as well as the sulfur compounds in general (ASTM D-130, ASTM D-849, ASTM D-1266, ASTM D-2324, ASTM D-3120, ASTM D-4045, ASTM D-6212, IP 107, IP 154) and especially corrosive sulfur compounds such as are determined by the Doctor test method (ASTM D-4952, IP 30). 

HEXACHLOROEPOXYOCTAHYDRO-e rfo,exo-DIMETHANO-NAPHTHA-LENE or HEXACHLORO-6,7-EPOXY-l,4,4A,5,6,7,8,8A-OCTA-HYDRO-l,4 5,8-DIMETHANONAPHTHALENE (60-57-1) C HgClgO Noncombustible or very difficult to bum solid. Incompatible with concentrated mineral acids, acid catalysts active metals strong oxidizers strong acids phenols, active metals and their salts (e.g., copper, iron, magnesium, potassium, sodium, zinc). Corrosive to some metals. 

Mobile, hygroscopic liquid. Characteristic amine odor-mp -4.9". bp7H) 128.9s bp( 20.0". df 1.007. ng 1.4540. Volatile with steam. Does not form an azeotrope with water. Flash pt, open cup 100 i (38"C), Surface tension at 20 = 37,5 dynes/cm. Viscosity at 20" = 2.23 cp. Dipole moment l. 58. Strong base, pKb 5.6. Corrosive to human skin. Miscible with water with evolution of some heat. Immiscible with coned NaOH solns. Also miscible with acetone, benzene, ether, castor oil, methanol, ethanol, ethyl ene glycol, 2-hexanone, linseed oil, turpentine, pine oil. Will dissolve 109% dimeihylamine 34% trimethylamine 33% methylamine > 5% naphtha < 1% paraffin oil < 5% sulfur. LDm orally in female rats l.05 g/kg, Smyth et al. Arch. 

Coal tar naphtha (71-43-2) is an indefinite term generally applied to the flammable coal tar distillates extracted at around 160 to 220°C. The term naphtha, however, is mostly applicable to petroleum products. Cresol (1319-77-3) is a mixture of methyl phenyl isomers extracted from the middle- to heavy-oil fractions (it is also derived from petroleum). Cresol is a toxic irritant and corrosive to skin and mucous membranes, which explains its common use as a disinfectant. 

For solid wastes to warrant management as hazardous wastes, they must meet one of four characteristics (flammability, corrosivity, reactivity, and toxicity) or be listed on one of four lists, although some otherwise hazardous wastes by these definitions are excluded. Hazardous wastes carry one or more identifying waste codes four digits comprised of a letter (D, F, K, P, or U) followed by three numbers. For example, a flammable hazardous waste, possibly waste naphtha, carries the waste code DOOL... 

Properties Water-wh. liq. sol. in alcohol, acetone, toluene insol. in water, petrol, naphtha m.w. 154.10 dens. 1.120-1.125 (25/40 C) flash pt. (COC) HOC ref. index 1.429 Toxicology Toxic and corrosive strong irritant to skin and tissue TSCA listed Precaution DOT Corrosive material combustible when exposed to heat or flame Hazardous Decomp. Prods. Heated to decomp., emits highly toxic fumes of POx Uses Catalyst in coatings, inks, for appliance, automotive, floor, furniture, paper, and other... 

The acidity of benzene, toluene, xylenes, naphthas, and other aromatic hydrocarbons is determined by the titration of a water extract with 0.01 N sodium hydroxide in the presence of 0.5% phenolphthalein indicator solution. The method is suitable for setting specifications, internal quality control, and development of solvents. The result indicates the potential corrosivity of solvent. 

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