Degrease metals

Spent materials are materials that have been used and can no longer serve the purpose for which they were produced without processing. For example, a solvent used to degrease metal parts will... 

Mixtures of liquid oxygen with dichloromethane, 1,1,1-trichloroethane, trichloroethylene and chlorinated dye penetrants 1 and T exploded violently when initiated with a blasting cap. Carbon tetrachloride exploded only mildly, and a partly fluorinated chloroalkane not at all. Trichloroethylene has been used for degreasing metallic parts before use with liquid oxygen, but is not safe. 

After degreasing, metals have to be blasted with a sufficiently abrasive material to remove the surface oxidation layer. Application of the abrasive to the metal surface to be cleaned depends very much on the dimensions and type of metal. Large dimensioned metals and interiors of such articles as tanks, will require application of the abrasive by means of air blasting techniques. Smaller metals of suitable strength can be treated in rumbler machines where the metals are tumbled whilst being blasted by the abrasive carried in an airstream. 

Solvents are commonly used for degreasing metal objects prior to processing as well as for cleaning purposes and in solution with other chemicals. There are many kinds in various chemical forms. The effects of some of these are examined below. 

Leukoderma was reported in two women engaged in degreasing metal parts with synthetic detergents containing polyoxyethylene (3-16), nonyl- or octylphenylether. Analysis revealed contamination with free alkylphe-nol, possibly octylphenol, or nonylphenol. Although a relationship between the cases of leukoderma and octyl- and nonylphenol exposure was suggested, it could not be confirmed. ... 

Tetrachloroethane is used as a solvent, for cleansing and degreasing metals, in paint removers, varnishes, lacquers, photographic film, resins and waxes, extraction of oils and fats, as an alcohol denaturant, in organic synthesis, in insecticides, as a weedkiller and fumigant and as an intennediate in the manufacture of other chlorinated hydrocarbons (Lewis, 1993). 

Trichloroethane is likely to enter the environment from air emissions or in wastewater from its production and use in vapour degreasing, metal cleaning and other applications. It can also enter the environment in leachates and volatile emissions from landfills. It has been detected at low levels in wastewater, groundwater, drinking-water, ambient water, ambient air, and urban air samples (United States National Library of Medicine, 1997). 

Tetrachloroethylene is a colorless, nonflammable liquid with properties similar to those of trichloroethylene. Its major use is for dry cleaning, and it has some applications for degreasing metals. 

A liquid waste which has a pH of less than or equal to 2 or greater than or equal to 12.5 is considered to be a corrosive hazardous waste. Sodium hydroxide, a caustic solution with a high pH, is often used to clean or degrease metal parts. Hydrochloric acid, a solution with a low pH, is used by many industries to clean metal parts prior to painting. When these caustic or acid solutions become contaminated and must be disposed, the waste would be a corrosive hazardous waste. 

Degreasing Metal cleaners Spot removers Water repellents... 

USE Dry cleaning degreasing metals solvent. therap cat Anthelmintic (Nematodes, Trematodes), THERAP CAT (VET) Anthelmintic. 

ORIGIN/INDUSTRY SOURCES/USES organic chemical industry, solvent for chlorinated rubber and other organic materials paint varnish rust remover soil fumigant cleansing and degreasing metals photo films resins and waxes extracant for oils and fats herbicide alcohol denaturant... 

OTHER COMMENTS used as a solvent and extractant for resins, oils, fats, waxes, and chlorinated rubber used as a paint and varnish remover, and as a commercial solvent for degreasing metal parts useful in the synthesis of hexafluoropropylene has also been used in the synthesis of thiokol polysulfide elastomers if some branching of the polymer structure is required. 

Ketones or chlorinated hydrocarbons, especially trichloroethylene, perchloro-ethylene, or dichloromethane, are used to degrease metals [14.251], [14.252]. The chlorinated hydrocarbons used to degrease light metals are stabilized to prevent the metal-catalyzed elimination of hydrogen chloride. The solvent mixture [14.253]-[14.256] for metal degreasing are being replaced by aqueous systems [14.257], [14.258] due to more stringent environmental protection requirements. See also Section 8.2.1.2. 

Trichloroethane [71-55-6] (methylchloroform) is insoluble in water, but miscible with organic solvents. It dissolves fats, oils, resins, waxes, bitumen, and asphalt. It is used to degrease metals as a solvent in the paint, adhesives, and plastics industries as well as an extracting agent for fats and ethereal oils. It is being increasingly replaced for environmental protection reasons by other systems. 

Uses Emulsifier and solubilizer for min. oils, fats and soivs. emulsifier for kerosene in agric. and pesticides sprays emulsifier for latex paints, metalworking fluids, soivs., specialty and industrial lubricants, detergents, cosmetics, degreasers, metal cutting oils emulsifier and lubricant in oil industries, textiles, leather, agric. defoamer Features Lipophilic... 

Uses Coemulsifier textile and leather dressing oils dye bath additive emulsifier in oiw and w/o emulsions for detergents, cosmetics, degreasers, metal cutting oils... 

Storage Store in cool, dry, well-ventilated area out of direct sunlight limit quantity stored Uses Intermediate in prod, of trichloroethylene solvent insecticide cleansing and degreasing metals paint removers varnishes lacquers photographic film resins waxes extraction of... 

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