Gallium phase separation

We have not demonstrated quantitative phase separation of salt from metal in the oxidation step. Approximately 5% of the gallium was carried over from the feed to the product after the calcium reduction. We are now scaling-up the 100-g experiments to plant-size equipment using magnesia crucibles in the equipment shown in Figure 3. 

Metallic liquids can also experience fractional crystallization. The abundances of trace elements such as gold, gallium, germanium, and iridium and the major element nickel in various classes of iron meteorites vary because of the separation of crystalline metal phases (kamacite or taenite). 

T = 7 . above which the liquid and gas phase are no longer distinguishable. Since the liquid can he continuously converted into Ihe gas phase without discontinuous change of properties by any path in the P — T diagram passing above the critical point, there is no definite boundary between liquid and gas. Two liquids ol similar molecules are usually. soluble in all proportions, but very low solubility is sufficiently common to permit the demonstration of as many as seven separate liquid phases in equilibrium at one temperature and pressure (mercury, gallium, phosphorus. perHuoro-kerosene, water, aniline, and heptane at 50 C. I atmosphere). 

Chemisorption of carbon dioxide on doped oxides prepared at 250° was also studied calorimetrically. Initial heats of adsorption on NiO(10 Li)(250°) (27 kcal/mole) and on Ni0(10 Ga)(250°) (28 kcal/mole) are similar. The gallium-doped oxide chemisorbs at room temperature the same quantity of carbon dioxide (9.3 cm /gm) as NiO(250°) (9.7 cm3/gm), whereas the quantity of gas adsorbed on Ni0(10 Li)(250°) is larger (13.0 cm /gm). Lithia chemisorbs carbon dioxide at room temperature. However, the difference between the quantities of gas adsorbed on pure and lithiated oxides is not explained by the presence of lithia, as a separate phase, in the doped sample. It seems, therefore, that carbon dioxide, as oxygen, is chemisorbed at room temperature on anionic vacancies whose concentration is particularly large on lithiated oxides. 

In a three-necked flask equipped with a nitrogen inlet, pressure-equalized dropping funnel and a copper-coil reflex condenser and provided with magnetic stirring were placed dry pentane (100 mL) and gallium(III) bromide (29.3 g, 0.095 mol). Over a 90 min period, diethylzinc (18.2 g, 0.148 mol) was slowly introduced. The mixture deposited a precipitate, presumably zinc bromide, with a marked heat evolution. After a 2 h reflux period, the reaction suspension was centrifuged and the separated liquid phase was freed of pentane. Distillation of the residue yielded 10 g (66%) of triethylgallium. bp 43-44 X (16 mm). A hydrolyzed sample of this product still showed the presence of trace amounts of zinc. 

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