Lithium selenates

The review selects the consistent result of the solubility of the stable lithium selenate, Li2Se04-H20, at standard conditions obtained in [89TAT/SER], [89VOJ/EBE], [980JK/CHR]  

A phase diagram or similar information is available for the systems Li2Se04-H2Se04-H20 at 303.15 K in [95HAV/MIC] Li2Se04-Cs2Se04-H20 at 303.15 Kin [2000HAV/MIC]. 

The standard Gibbs energy of formation of lithium selenate is calculated from the Gibbs energy of Reaction (V.l89) and the selected values of AfG° for the ions and water to be  

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Lithium selenate, LigSeO —Neutralization of selenic acid with lithium carbonate and concentration of the solution yields, according to the temperature, either the monoclinic hydrate, LiaSe04,H20, or the rhombic anhydrous salt.11... 

KI3H20 potassium triiodide monohydrate 7790-42-3 25 00 3.5000 1 2296 Li2H205Se lithium selenate monohydrate 7790-71-8 25.00 2.5600 1 1... 

SEL/SHN] Selivanova, N. M., Shneider, V. A., Sazykina, T. A., Physicochemical properties of selenates. XII. Heat of formation from the elements of lithium selenate, Izv. Vyssh. Uchebn. Zaved, Khim. Khim. TekhnoL, 5, (1962), 183-187, in Russian. Cited on pages 415,469. 

Havlicek, D., Micka, Z., Barborak, V., Smejkal, P., Cesium and cesium-lithium selenates. Collect. Czech. Chem. Commun., 65, (2000), 167-178. Cited on pages 415, 429. 

Fluor-jod, n. iodine fluoride, -kalium, n. potassium fluoride, -kalzium, n. calcium fluoride, -kiesel, m. silicon fluoride, -kie-selsaure,/. fluosilicic acid, -kohlenstoff, m. carbon fluoride, -lithium, n. lithium fluoride. -metall, n. metallic fluoride, -natrium, n. sodium fluoride, -phosphat, n. fluophosphate. -phosphor, m. phosphorus fluoride, -salz, n. fluoride, -schwefel, m. sulfur fluoride, -selen, n. selenium fluoride, -silber, n. silver fluoride, -silikat, n. fluo-silicate. -silizium, n. silicon fluoride, -sili-ziumverbindung, /. fluosilicate. -tantal-sMure, /. fluotantalic acid, -tellur, n. tellurium fluoride, -titan, n. titanium fluoride, -toluol, n. fluorotoluene, fluotoluene. 

In an effort to make productive use of the undesired C-13 epimer, 100-/ , a process was developed to convert it into the desired isomer 100. To this end, reaction of the lactone enolate derived from 100-) with phenylselenenyl bromide produces an a-selenated lactone which can subsequently be converted to a,) -unsaturated lactone 148 through oxidative syn elimination (91 % overall yield). Interestingly, when 148 is treated sequentially with lithium bis(trimethylsilyl)amide and methanol, the double bond of the unsaturated lactone is shifted, the lactone ring is cleaved, and ) ,y-unsaturated methyl ester alcohol 149 is formed in 94% yield. In light of the constitution of compound 149, we were hopeful that a hydroxyl-directed hydrogenation52 of the trisubstituted double bond might proceed diastereoselectively in the desired direction In the event, however, hydrogenation of 149 in the presence of [Ir(COD)(py)P(Cy)3](PF6)53 produces an equimolar mixture of C-13 epimers in 80 % yield. Sequential methyl ester saponification and lactonization reactions then furnish a separable 1 1 mixture of lactones 100 and 100-) (72% overall yield from 149). 

Other compounds may be found in leachate from landfills, e.g., borate, sulfide, arsenate, selenate, barium, lithium, mercury, and cobalt. In general, however, these components are not often measured when they are measured, they are usually present in very low concentrations and are considered only of secondary importance. 

JK/CHR] Ojkova, T., Christov, C., Mihov, D., Investigation of the aqueous lithium and nickel selenate system, Z. Phys. Chem. (Munich), 203, (1998), 87-93. Cited on pages 314,415, 578, 580. 

In many cases a l-chloro-2-amino derivative is used as a starting material. The 2-aryl-selenazolopyridine (51) can be prepared directly from the l-chloro-2-amino intermediate without prior selenation by reaction of the lithium amide with the arylselenoester (Equation (8)) <87S363, 94H(37)323>. 

Iron(II) fluoride Iron(II) hydroxide Iron(III) hydroxide Iron(III) phosphate dihydrate Lanthanum iodate Lead(II) bromide Lead(II) carbonate Lead(II) chloride Lead(II) fluoride Lead(II) hydroxide Lead(II) iodate Lead(II) iodide Lead(II) selenate Lead(II) sulfate Lithium carbonate Lithium fluoride Lithium phosphate Magnesium carbonate Magnesium carbonate trihydrate... 

Miscellaneous compounds Cesium trihydrogen selenite Lithium trihydrogen selenite Potassium selenate Methyl ammonium alum (MASD) Ammonium cadmium sulfate Ammonium bisulfate Ammonium sulfate Ammonium nitrate Colemanite Cadmium pyroniobite Gadolinium molybdate... 

EXPLOSION and FIRE CONCERNS combustible solid NFPA rating (NA) reacts to form explosive products with metal amides contact with acids may cause formation of poisonous hydrogen selenide gas incompatible or reacts violently with barium carbide, bromine pen-tafluoride, chromic oxide, fluorine, lithium carbide, lithium silicon, metals, nickel, sodium, nitric acid, nitrogen trichloride, oxygen, potassium, potassium bromate, rubidium carbide, zinc, silver bromate, uranium, strontium carbide, and thorium carbide toxic gases and vapors may be released in a fire involving selenium, sodium selenite, sodium selenate, and selenium dioxide use water for firefighting purposes. 

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