Ammonia metallurgy

Cobalt(II) oxalate [814-89-1], C0C2O4, is a pink to white crystalline material that absorbs moisture to form the dihydrate. It precipitates as the tetrahydrate on reaction of cobalt salt solutions and oxaUc acid or alkaline oxalates. The material is insoluble in water, but dissolves in acid, ammonium salt solutions, and ammonia solution. It is used in the production of cobalt powders for metallurgy and catalysis, and is a stabilizer for hydrogen cyanide. 

Duyvesteyn, W. P. C. Sabacky, B. J. Ammonia Leaching Process for Escondida Copper Concentrates (Reprinted from Extractive Metallurgy of Copper, Nickel, and Cobalt. Vol. 1, 1993). Trans. Inst. Min. Metall. Sect. C-Miner. Process. Extr. Metall. 1995, 104, C125-C140. 

The principal current U. S. requirements for industrial hydrogen are for use in petroleum refining, for the manufacture of ammonia and methanol, and for a wide variety of small uses including chemicals manufacture, metallurgy, welding, etc. It is beyond the scope of this paper to discuss the factors that will affect the future requirements for ammonia, methanol, and small-user hydrogen however, these factors are discussed rather completely in Reference 1. 

Metallurgy. In this application ammonia is cracked to produce a dissociated ammonia that consists of 75 percent hydrogen and 25 percent nitrogen. Dissociated ammonia is used in a number of metal treatment proceses.57... 

Table 1.21 provides an idea of the average commercial speciheations of anhydrous ammonia depending on uses for the production of fertilizers, refrigeration and metallurgy. 

Ores of silver native silver, argentite, cerargyrite (horn silver). Metallurgy of silver cyanide process, amalgamation process, Parkes process. O mpoimds of silver silver oxide, silver chloride, silver bromide, silver iodide, silver ammonia complex, silver cyanide complex, silver thiosulfate complex, silver nitrate. 

Use Powder metallurgy products, magnets, high-frequency cores, auto parts, catalyst in ammonia synthesis. 

For the production of hydrogen (ammonia, refinery purposes, petrochemistry, metallurgy, fuel cells), the carbon monoxide contained in the effluent stream is converted to additional hydrogen in high and low temperature shift reactors. The water gas-shift reaction (WGS) is ... 

The small proportion of commercially produced ammonia not incorporated into fertilizers is used as a corrosion inhibitor, in the purifrcation of water supplies, as a component of household cleaners, and as a refrigerant. It is also used in the pulp and paper, metallurgy, rubber, food and beverage, textile, and leather industries. Ammonia is used in the manufacture of pharmaceuticals and explosives, and in the production of various chemical intermediates (LeBlanc et al. 1978 Sax and Lewis 1987). 

Low temperature metallurgy divides naturally into ranges dictated by material impact properties, as shown in Figure 7-137. The first, extending down through -50°F, is widely involved in ammonia and propylene production and requires impact tested carbon steel. 

Although there is no cyanamide production In the United States, by far the larger production of the American Cyana-mid Company s plant at Niagara Falls, Canada, enters this country either as cyanamide or crude cyanide. The cyanamide is consumed directly In mixed fertilizers where It can be used in proportions of only about 60 pounds of cyanamide to a ton of fertilizer, or it is autoclaved at the Ammo-Phos Works, Warners, New Jersey, for the production of ammonia for ammonium phosphate. The crude cyanide is used in metallurgy, in the production of hydrocyanic acid for fumigation and the yellow and blue prusslates at the New Jersey plant. 

X. Meng, K. Han, The principles and applications of ammonia leaching of metals . Mineral Processing and Extractive Metallurgy Review, 16 (1) (1996), pp. 23-61. 

K. Osseo-Asare, Application of activity-activity diagrams to ammonia hydrometallurgy Fe-NH3-H20, Fe-NH3-H20-C03 and Fe-NH3-H20-S04 systems at 25 °C , Transactions of Institute of Mining and Metallurgy, 90 (1981), pp. 159-164. 

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