Lithium aluminate Processing

Zeta lithium aluminate lithia-precursor for processing of lithia-stabilized beta"-alumina 18, 17.3.7.1.1... 

Z. Weyberg reported crystals of lithinm chromite, LiCrOg, to be formed along with lithium aluminate when mixtures of an excess of lithium chromate with china clay are calcined. The brown powder consists of microscopic, isotropic, octahedral crystals. As previously indicated, there are differences of opinion as to the nature of the green liquid obtained when freshly precipitated hydrated chromic oxide is treated with alkali-lye. The process is one of either peptization or dissolution or else it includes both. R. Kremann, M. Kreps, and J. K. Wood and V. K. Black consider that the soln. of hydrated chromic oxide in alkali is chromite while W. Herz and H. W. Fischer, A. Hantzsch, C. F. Nagel, W. V. Bhagwat and N. R. Dhar, and H. B. Weiser consider it to be peptized, hydrated chromic oxide. C. Fricke and... 

Often the powders to be used in tape casting are very hygroscopic. They either pick up moisture readily from the atmosphere or were never properly dried and stored in the first place. Materials like this must be dried prior to batching in order to remove the physically adsorbed moisture from the particle surfaces and from between the particles. This water is sometimes referred to as free water, or water of hydration. Materials such as lithium aluminate are notorious for adsorbing moisture from the atmosphere. These materials are dried and stored in an oven at greater than 100°C, and they are added to the ball mill directly from the oven. In the development of the Western Electric process described in the previous section, it was... 

Another use for silane treatment as well as for organics such as steric acid or octadecanoic acid has been to protect the surface of the particles from hydration so that they can be processed in a water-based system. Aluminum nitride, some of the ceramic superconductors, and materials like lithium aluminate fall into this category. The use of an organic "shield to produce a monolayer of hydrophobic material on the surface has been reviewed in several articles. 

Data on the mechanism of lithium sorption from liquors with freshly precipitated aluminium hydroxide are limited and contradictory. For example, Goodenough reports on the isolation of lithium-aluminate complex [17]. Some authors [11] suggest that lithium is adsorbed on the surface of aluminium hydroxide, and high adsorption coefficient is provided by the presence of salt background which prevents aluminium hydroxide from crystallization when the temperature of the process is raising. Other authors assume that lithium coprecipitation with aluminium hydroxide leads to intercalation of lithium into the structure of the latter and to the formation of lithium-containing aluminium hydroxide characterized by pseudo-boehmite structure [12]. The authors of [13] conclude that the overall interaction of lithium with amorphous aluminium hydroxide can be represented by the following scheme ... 

In vacuum thermochemical reduction process, aluminum and silicon are suitable reduction agents [5, 6]. Vacuum aluminothermic reduction lithium is from a US patent about aluminum reduction of lithium oxide. Aluminum reduction of spodumene has been reported by Stauffer [7]. Lithium is difficultly reduced if not adding calcium oxide into spodumene. When the mass ratio of calcium oxide and spodumene is 3 2, the maximum productivity was 92.2% under the conditions of 1050 1150"C for 2 hours. Fedorov and Shamrai used aluminum to reduce lithium aluminate, and pointed out that the lithium productivity could reach 95% when the reduction temperature was 1200 C and the system pressure was below 0.0013 Pa [4]. The previous researches were focused on the production of lithium. But the recovery of reduction residue was not investigated. In present work, a novel vacuum aluminofliermic reduction lithium process is developed which used lithium carbonate, alumina and calcium oxide as raw materials. The products were metal lithium and high-whiteness aluminum hydroxide. 

Nitriles can be converted into primary amines by lithium tetrahydrido-aluminate or diborane. The products of such reactions, unlike those of catalytic hydrogenation, contain only small amounts of secondary and primary amines, so that these processes are particularly suitable for small batches in the laboratory. Alkali hydridoborates do not effect this reduction. 0.5 mole of lithium tetrahydridoaluminate is necessary for reduction of 1 mole of nitrile, but using an excess of reductant leads to better yields a 1 1 ratio is generally applied. Amundsen and his coworkers28 studied the optimal conditions for this reduction and describe reduction of heptyl cyanide as an example of a generally applicable procedure ... 

The hydration process in OPC+CAC blends may also be accelerated by adding small amoimts of a lithium salt, such as Li2C03, to the mix. The hthium salt, which accelerates the hydration of the monocalcium aluminate phase very effeetively, is also highly effective in mixes in which the calcium aluminate cement is the minor component. 

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