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Lithium phosphates formation

Amorphous aluminum oxide has recently been proved to extract lithium from brines and bitterns having lithium concentrations of 0.83 and 13.1 mg/1, respectively. The sorption may be explained by the formation of hydrous lithium aluminum oxide. The sorption capacity of amorphous hydrous aluminum oxide was found to be 4.0 mmol/g. For brines and bitterns the lithium concentration factors on the sorbent attained values of 370 and 130, respectively equilibrium was reached after 7 days. The desorption of lithium ions was carried out with boiling water yielding a maximum concentration factor of lithium in the eluate of 46 in reference to the initial lithium concentration of the brines. Lithium was separated from the eluates by solvent extraction with cyclohexane containing thenoyltrifluoracetone and trioctyl-phosphine oxide, subsequent back extraction with hydrochloric acid, and precipitation of lithium phosphate by addition of K3P04. The purity of the precipitate amounted to at least 95% I7 21). [Pg.96]

In lithium phosphate melts where lithium hexametaphosphate crystallized as a phase, melt composition should have yielded a linear hexapolyphosphate if everything had occurred as planned. We recognized that an attempt to prepare hexapolyphosphate was little more than a blind gamble. If lithium hexapolyphosphate had been a member of this phase family, all conditions were optimized for its formation, but it is not found as a stable alkali metal compound derived by melt crystallization. As noted below, calcium hexapolyphosphate can be crystallized from a melt, but usually with great difficulty. ... [Pg.142]

The coupling reaction between lithium dimethylcuprate and acyclic enol phosphates must be carried out between -47 and -98 C for stereoselective formation of g-methyl-a,g-unsaturated esters. [Pg.19]

The formation of g-alkyl-a,g-unsaturated esters by reaction of lithium dialkylcuprates or Grignard reagents in the presence of copper(I) iodide, with g-phenylthio-, > g-acetoxy-g-chloro-, and g-phosphoryloxy-a,g-unsaturated esters has been reported. The principal advantage of the enol phosphate method is the ease and efficiency with which these compounds may be prepared from g-keto esters. A wide variety of cyclic and acyclic g-alkyl-a,g-unsaturated esters has been synthesized from the corresponding g-keto esters. However, the method is limited to primary dialkylcuprates. Acyclic g-keto esters afford (Zl-enol phosphates which undergo stereoselective substitution with lithium dialkylcuprates with predominant retention of stereochemistry (usually > 85-98i )). It is essential that the cuprate coupling reaction of the acyclic enol phosphates be carried out at lower temperatures (-47 to -9a°C) to achieve high stereoselectivity. When combined with they-... [Pg.21]

The early patent disclosures have claimed the application of a wide spectrum of gas-evolving ingredients and phosphorus-based organic molecules as flame retarding additives in the electrolytes. Pyrocarbonates and phosphate esters were typical examples of such compounds. The former have a strong tendency to release CO2, which hopefully could serve as both flame suppressant and SEI formation additive, while the latter represent the major candidates that have been well-known to the polymer material and fireproofing industries.The electrochemical properties of these flame retardants in lithium ion environments were not described in these disclosures, but a close correlation was established between the low flammability and low reactivity toward metallic lithium electrodes for some of these compounds. Further research published later confirmed that any reduction of flammability almost always leads to an improvement in thermal stability on a graphitic anode or metal oxide cathode. [Pg.162]

Pairs of W5+ ions were observed in lithium-tungsten phosphate glasses.35 The effectiveness of pair formation increased as the Li+ concentration increased. Interspin distances were calculated from the dipolar splitting, D. The mean distance between W5+ ions decreased from 4.53 A for the glass without Li+ ions to 3.70 A for glasses containing 50 mol% Li+. [Pg.322]

I-Alkynes from methyl ketones This reaction can be effected by conversion to Ihe enol phosphate followed by -elimination with LDA (equation I). In the case of a simple ketone such as 2-octanone the yield is low because of formation also of an allene. In such cases lithium tetramethylpiperidide is recommended as base. [Pg.243]


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See also in sourсe #XX -- [ Pg.51 ]




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Lithium phosphate

Phosphate formation

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