Magnesium reduction process

Magnesium-Reduction (Kroll) Process. In the 1990s, nearly all sponge is produced by the magnesium reduction process (Fig. 4). 

Kroll (magnesium-reduction) process manufacture of, 24 851—853 price history of, 24 861t sodium-reduction process manufacture of, 24 853... 

Beryllium fluoride is the intermediate compound in the magnesium-reduction process to produce beryllium metal. The compound also is used in the manufacture of glass, and in nuclear reactors. 

This process is entirely satisfactory in operation and in the quality of the metal produced from it a high proportion of the early uranium fuel for experimental and power reactors in the U.K. was of this type. It has, however, now been rendered obsolete by the magnesium reduction process which gives an equally satisfactory product at a lower cost. 

An all metal plant made, for example, of inconel, is presumably as successful for the manufacture of pure titanium as for zirconium, but details have not been published. The commercial demand for the very highest grade titanium is, in any case, less than that for zirconium of comparable purity, and for most purposes titanium made by the Kroll magnesium reduction process is quite satisfactory. 

Attention was focused on the crystal bar zirconium made by the iodide route in addition to the Kroll magnesium reduction process. The iodide decomposition route gives a superior product, but at a higher cost. 

Fig. 9.1. Extraction of uranium (acid leach, ion-exchange, fluidization and magnesium reduction process).

Fig. 9.9. Extraction of niobium (chlorination, hydrogen purification, magnesium reduction process).

Fig. 9.12. Extraction of vanadium (chlorination, distillation, magnesium reduction process).

Electrolytic Reduction. The largest manufacturers of magnesium use processes based on the electrolytic reduction of magnesium chloride... 

Sodium reduction processes are also described for tantalum (115), siHcon (116—118), magnesium (119), and other metals. 

The 1990s reduction process was based on work started in the early 1930s. A magnesium vacuum reduction process was developed for reduction of titanium tetrachloride to metal. Based on this process, the U.S. Bureau of Mines (BOM) initiated a program in 1940 to develop commercial production. Some years later, the BOM pubHcized its work on titanium and made samples available to the industrial community. By 1948, the BOM produced batch sizes of 104 kg. In the same year, Du Pont aimounced commercial availabiHty of titanium, thus beginning the modem titanium metals industry (1). 

Reduction of uranium tetrafluoride by magnesium metal has been described in detail (40,53). It is often referred to as the Ames process, since it was demonstrated at the Ames Laboratory in early 1942. The reaction is very exothermic and the reduction process is carried out in a sealed bomb due to... 

To improve magnesium reduction, which also improves siHca reduction in cold process softening, sodium aluminate may be used. The sodium aluminate provides hydroxyl ion (OH ) needed for improved magnesium reduction, without increasing calcium hardness in the treated water. In addition, the hydrolysis of sodium aluminate results in the formation of aluminum hydroxide, which aids in floe formation, sludge blanket conditioning, and siHca reduction. 

Refractory metals Zirconium Hafnium Titanium Kroll process, chlorination, and magnesium reduction Chlorine, chlorides, SiCli Wet scrubbers... 

According to the method developed by Izumi [593], magnesium chloride is added to the reactor as a diluent, along with K2TaF7 and NaCl, prior to the reduction process. The powder obtained by the above method is washed and treated thermally at 1200°C in vacuum. The final product has a specific capacitance of 12,000 p.C/g, contains 1800 ppm of oxygen, and its Mg content is as low as 20 ppm. 

Thermal magnesium, i.e., magnesium produced by the Pidgeon process earlier and by the magnefherm process at present, constitutes only 30% of the total magnesium production. The rest is produced electrolytically in which the leading examples are (i) the Dow electrolytic reduction process, and (ii) Norsk hydro process. 

Carborods, 4 201, 202 Carbosulfan, 2 550t Carbothermal reduction, 77 210-211 as magnesium manufacturing process, 75 342... 

Beryllium fluoride (BeFj) is an example of beryllium that has an oxidation state of +2, combining with a negative anion element with an oxidation state of—1. BeryUiiun fluoride is also used along with magnesium metal in the chemical reduction process to produce beryllium metal. 

The separator is often the weakest component in any electrochemical cell. There are also difficulties in employing ion-exchange diaphragms in aprotic media. Particularly with large industrial cells, it is advantageous to devise reaction conditions that allow the use of an undivided cell. One solution to these problems for an electrochemical reduction process employs a sacrificial anode of magnesium, alumin-... 

Although many commercial processes have heen developed since the first electrolytic isolation of Mg metal hy Davy and Faraday, and Bussy, hy chemical reduction, the principles of the manufacturing processes have not changed. At present, the metal is most commonly manufactured by electrolytic reduction of molten magnesium chloride, in which chlorine is produced as a by-product. In chemical reduction processes, the metal is obtained by reduction of magnesium oxide, hydroxide, or chloride at elevated temperatures. 

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