Lithium chloride powder

One procedure makes use of a box on whose silk screen bottom powdered desiccant has been placed, usually lithium chloride. The box is positioned 1-2 mm above the surface, and the rate of gain in weight is measured for the film-free and the film-covered surface. The rate of water uptake is reported as u = m/fA, or in g/sec cm. This is taken to be proportional to - Cd)/R, where Ch, and Cd are the concentrations of water vapor in equilibrium with water and with the desiccant, respectively, and R is the diffusional resistance across the gap between the surface and the screen. Qualitatively, R can be regarded as actually being the sum of a series of resistances corresponding to the various diffusion gradients present ... 

Lithium chloride [7447-41-8] M 42.4, m 600 , 723 . Crysld from water (ImL/g) or MeOH and dried for several hours at 130 . Other metal ions can be removed by preliminary crystallisation from hot aqueous 0.0 IM disodium EDTA. Has also been crystallised from cone HCl, fused in an atmosphere of dry HCl gas, cooled under dry N2 and pulverised in a dry-box. Kolthoff and Bruckenstein [J Am Chem Soc 74 2529 1952] ppted with ammonium carbonate, washed with Li2C03 five times by decantation and finally with suction, then dissolved in HCl. The LiCl solution was evaporated slowly with continuous stirring in a large evaporating dish, the dry powder being stored (while still hot) in a desiccator over CaCl2. 

Available from Alfa Inorganics. If necessary, finely powdered lithium chloride can be dried by heating under vacuum (0.1 mm.) at 100° for several hours. 

Requirements for safe storage of powdered Al, Hf, Mg, Ti, Zn and Zr are outlined. Fires are best extinguished with various fluxes, trimethyl boroxine, asbestos fines ( ), talc, graphite, sodium chloride, soda ash, lithium chloride or powdered dolomite [ ] Slurries of Al, Cd, Cu, Ge, In, Ni, Pb, Sn or Zn produced by metal atom-solvent cocondensation at — 196°C are extremely active chemically [2], and would be pyrophoric on exposure to air. 

Lithium.—In order to extract lithium from the silicate minerals—petalite, lepidolite, spodumene, amblygonite, etc.—J. J. Berzelius 3 fused the finely powdered mineral with twice its weight of calcium or barium carbonate. L. Troost fused a mixture of finely powdered lepidolite with an equal weight of barium carbonate, half its weight of barium sulphate, and one-third its weight of potassium sulphate. In the latter case, two layers were formed lithium and potassium sulphates accumulated in the upper layer from which they were extracted by simple lixiviation. The sulphates are converted to chlorides by treatment with barium chloride. The filtered liquid is evaporated to dryness, and the chlorides extracted with a mixture of absolute alcohol, or pyridine. The lithium chloride dissolves, the other alkali chlorides remain as an almost insoluble residue. 

Sample powders were dried in a vacuum oven at 60 C for 7 hours and cooled to minimize the hysteresis effect prior to storage in the dessicators of various water activities. In addition to Drierite, five saturated salt solutions were used in dessicators. These salt solutions were lithium chloride, magnesium chloride, potassium carbonate, sodium nitrite and potassium chloride. Their water activities were 0.110, 0.330, 0.440, 0.650 and 0.850, respectively, at 20 C. Each sample contained 1.2 to 1.5 g powder and four-week equilibration time was employed. The percentage of... 

Reagent grade anhydrous lithium bromide powder (Matheson, Coleman and Bell) was used after drying in a vacuum oven at 100°-120°C. Potassium chloride (Fisher certified ACS) was dried at 110°C and used to calibrate the conductance cell. Deionized water from the laboratory supply was piped directly into a Pyrex glass still (Corning model AG-la) and distilled into a polyethylene vessel, where it was kept until needed. The specific conductance of the water was 1 X 10 6 12 1 cm-1. 

Zirconium chloride is a white powder, and lithium nitride is a black powder. When this reaction proceeds, the lithium chloride forms as a liquid just as the iron forms as a liquid in the thermite reaction. The melting point of lithium chloride is 605°C (the melting point of iron is 1536°C ) The temperature of the zirconium chloride/lithium nitride reaction reaches 1370°C less than 1 second after the reaction is initiated. This liquid plays the same role as the flux agents already discussed It provides a medium for rapid mixing of reagents. 

A poorly crystalline "rag" structure has been described for synthetic product obtained by the reaction between molybdic chloride and lithium sulphide in tetrahydrofuran. The product was purified by repeated washing with tetrahydrofuran to remove the lithium chloride. Heat treatment of the amorphous powder gave a low degree of crystallization. 

Methyl-5-plienyl-l,2-oxatellurolium Bromide 0.87 g (10 mmol) of anhydrous lithium bromide are dissolved in 20 ml of acetone, 0.61 g (2.0 mmol) of 3-methyl-5-phenyl-l,2-oxatellurolium chloride powder are added, and the mixture is heated under reflux for 10 min. The solvent is then evaporated under vacuum, the residue is shaken with a mixture of 40 ml of dichloromethane and 40 ml of water, and the organic phase is separated, dried with anhydrous sodium sulfate, filtered, and evaporated. The residue is recrystallized from acetonitrile yield 0.54 g (78%) m.p. 122°. 

Historically it is of interest that an early, albeit unsuccessful, attempt to detect NMR in bulk matter was performed with powdered lithium chloride [25]. Only later did it become clear that under the experimental conditions used the Li resonance was probably saturated. The first Li NMR signal was recorded in 1946 [26], while Li was measured a few years later [27]. High-resolution spectra for Li were then reported in 1962 [28] and for Li in 1976 [29]. For completeness we mention that nuclear properties of the short-lived... 

The potassium salt is a white crystalline powder, more soluble in lithium salt solutions than in pure water. The solution is not stable Moderate acidification leads to a mixtureof [a,-P2Wn08,] and [P8W480,84] anions. The half-wave potentials (V vs SCE) in molar acetic acid-lithium acetate buffer are - 0.59 (2e) and —0.69 (2c). The PNMR spectrum of a freshly prepared solution in lithium chloride exhibits a single resonance at -8.6ppm. In the IR spectrum, the P—O bands are at 1130, 1075, and 1012 cm" (KBr pellet). 

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