Cleaning of metals

Hexafluorozirconic acid is used ia metal finishing and cleaning of metal surfaces, whereas the fluorozirconates are used in the manufacture of abrasive grinding wheels, in aluminum metallurgy, ceramics industry, glass manufacturing, in electrolytic cells, in the preparation of fluxes, and as a fire retardant (see Abrasives Metal surface treati nts). 

Blasting in, or incidental to cleaning of metal castings, in connection with their manufacture 1 month... 

Aqueous solutions of acids as used in metal cleaning processes such as pickling for the removal of rust or rolling scale during the production and fabrication of metals, or in the post-service cleaning of metal surfaces. 

Acid Pickling and Acid Cleaning of Metal Surface. 1192... 

Ultrasound enhanced the rate of dissolution of zinc metal in alkaline media, 2-3 times in sonicated condition rather than the unsonicated condition, due to the cleaning of metal surface in ultrasonic field. Decomposition of Zn-dithizone complex was also observed in ultrasonic field. In sonicated samples, the peak of... 

Immersion-cell continuous pH measurement, 14 33 Immersion cleaning, of metal surfaces,... 

Spray cleaning, of metal surfaces, 16 213 Spray coating processes, 7 23, 68-76 economic aspects, 7 75-76 Spray column absorbers, 1 27 Spray cone angle, 23 187 Spray correlations, 23 189-192 Spray deposition, of metal-matrix composites, 16 173 Spray-dried products, 11 542-543 Spray-dried resins, production of,... 

Lyman, T., ed. 1984. "Blast Cleaning of Metals." Metals Handbook. The American Society for Metals, Cleveland. 

Spencer, L.F. April 1962. "The Cleaning of Metals Part 1 - Alkaline cleaning. Metal Finishing. Pp. 59-60. 

Chemical passivation should be started as soon as possible after the cleaning of metal surfaces. Accumulation of new corrosion products can occur if it is not initiated soon after cleaning. It may be achieved by treating equipment... 

Hydrochloric acid is replacing sulfuric acid in some applications such as metal pickling, which is the cleaning of metal surfaces by acid etching. It leaves a cleaner surface than sulfuric acid, reacts more slowly, and can be recycled more easily. It is used in chemical manufacture especially for phenol and certain dyes and plastics. In oil well drilling, it increases the permeability of limestone by acidifying the drilling process. 

The type of solvent to be used and synergistic effects on the US-assisted cleaning of metal surfaces depend greatly on the target surface and the subsequent treatment to which the clean surface is to be subjected. 

Even careful experimenters stumble into this pitfall. For example, see reference (9) of Problems 38 and 16. Furthermore, it is surprising to learn that a number of well established reactions will not go if the reagents and glass equipment are exhaustively cleaned of metallic impurities. An example is the Grignard reaction. 

Tetrachloroethylene and trichloroethylene are used for the cleaning of metals finely purified and for dry cleaning of clothes as the cleaning solvents. As they are very poisonous we have to take care not to pollute the environment with these compounds. When we accidentally litter the environment with these compounds, the cleaning methods which remove them effectively using bacteria may be helpful. 

Objective 4 62. Fiydrochloric acid is used in the cleaning of metals (called pickling). Fiydrogen... 

The most common use for nitric acid is in the manufacture of ammonium nitrate, which, in turn, is used primarily as a fertilizer. About three-quarters of all nitric acid produced in the United States is used in fertilizers. The second most important application, accounting for about 10 percent of all nitric acid produced, is in the production of adipic acid [C00H(CH2)3C00H], used in the manufacture of nylon, polyurethanes, and other synthetic plastics. Nitric acid is also used to make a variety of metal nitrates and for the cleaning of metals. Small amounts of the compound are used for a variety of other applications, including ... 

MAJOR USES Used in the production of paint removers, resins, waxes, insecticides, weed killers, fumigants, trichloroethylene and tetrachloroethylene photographic development degreasing and cleaning of metals. 

ORIGIN/INDUSTRY SOURCES/USES not a natural product wastewater discharges stack fugitive emissions from production volatilization losses from use in cold cleaning of metals losses from vapor degreasing solvent, aerosol spray used in cleaning agents and pesticides... 

The calcium tartrate is removed by filtration and treated with dilute sulfuric acid to produce a solution of tartaric acid and a precipitate of calcium sulfate. The tartaric acid is then concentrated by evaporation under reduced pressure and separated by crystallisation. Tartaric acid is widely used in the food and drink industries, in pharmaceutical preparations, as a retarding agent in plaster and gypsum formulations, and in the polishing and cleaning of metals. Food grade slaked lime is generally specified (e.g., [31.30] and Table 31.2). 

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