Lithium compounds oxidation

The corrosion resistance of lithium electrodes in contact with aprotic organic solvents is due to a particular protective film forming on the electrode surface when it first comes in contact witfi tfie solvent, preventing further interaction of the metal with the solvent. This film thus leads to a certain passivation of lithium, which, however, has the special feature of being efiective only while no current passes through the external circuit. The passive film does not prevent any of the current flow associated with the basic current-generating electrode reaction. The film contains insoluble lithium compounds (oxide, chloride) and products of solvent degradation. Its detailed chemical composition and physicochemical properties depend on the composition of the electrolyte solution and on the various impurity levels in this solution. 

In other cases, crystal lattice decomposition occurs under cathodic insertion of lithium, and the cathodic process becomes irreversible. In this case, the product of the cathodic reaction is a mixture of a lithium compound (oxide, chalcogenide) with a reduced form, particularly, directly with a metal. It is such processes that occur when iron sulfide or copper oxide are used ... 

An emerging electrochemical appHcation of lithium compounds is in molten carbonate fuel ceUs (qv) for high efficiency, low poUuting electrical power generation. The electrolyte for these fuel ceUs is a potassium carbonate—hthium carbonate eutectic contained within a lithium aluminate matrix. The cathode is a Hthiated metal oxide such as lithium nickel oxide. 

Lithium peroxide is a strong oxidizer and can promote combustion when in contact with combustible materials. It is a powerful irritant to skin, eyes, and mucous membranes (2) protective clothing should be worn when handling lithium peroxide. The LD q has not been deterrnined, and there is no designated threshold limit value (TLV). However, 5 g of many lithium compounds can be fatal. 

Hot oleum (>50°C), strong alkalis, fluoride solutions, sulphur trioxide Strong alkalis, especially >54°C, distilled water >82°C, hydrofluoric acid, acid fluorides, hot concentrated phosphoric acid, lithium compounds >1 77°C, severe shock or impact applications Strong oxidizers, very strong solvents... 

Lithium-nickel oxides form various lithium compounds, lithium hydroxides (LiOH), Li2C03, nickel hydroxide (Ni(OH)2), nickel carbonate (NiC03) and nickel oxide (NiO). Figure 51 shows the discharge characteristics of lithium-nickel oxides synthesized from these compounds. They were heat-treated at 850 °C for 20 h in air. Although the lithium nickel oxides showed a smaller discharge capacity than that of LiCo02, LiOH and Ni(OH)2 were considered to be appropi-ate raw materials. 

D.12 Write the formula for the ionic compound formed from (a) strontium and bromide ions (b) aluminum and sulfate ions (c) lithium and oxide ions (d) ammonium and sulfide ions ... 

In the 1980s it was shown that during cathodic polarization of some solid compounds (oxides, halcogenids) in aprotic solvents containing dissolved lithium salts, an incorporation of lithium atoms is possible. On titanium dioxide this reaction can be written as... 

At the end of the 1990s in Japan, large-scale production of rechargeable lithium ion batteries was initiated. These contained lithium compounds intercalated into oxide materials (positive electrodes) as well as into graphitic materials (negative electrode). The development of these batteries initiated a further increase in investigations of the properties of different intercalation compounds and of the mechanism of intercalation and deintercalation processes. 

These observations (confirmed by AES studies) indicate that after longer oxidation times the top surface is completely covered by lithium compounds, i.e. that the oxidation of lithium has become dominant. This implies a depletion of the element within the metal surface, i.e. the presence of a soft surface layer. 

Finally, Al (/= 5/2) and Co NMR spectroscopy have been used to probe AP+ in Al-doped lithium cobalt oxides and lithium nickel oxides. A Al chemical shift of 62.5 ppm was observed for the environment Al(OCo)e for an AP+ ion in the transition-metal layers, surrounded by six Co + ions. Somewhat surprisingly, this is in the typical chemical shift range expected for tetrahedral environments (ca. 60—80 ppm), but no evidence for occupancy of the tetrahedral site was obtained from X-ray diffraction and IR studies on the same materials. Substitution of the Co + by AF+ in the first cation coordination shell leads to an additive chemical shift decrease of ca. 7 ppm, and the shift of the environment A1(0A1)6 (20 ppm) seen in spectra of materials with higher A1 content is closer to that expected for octahedral Al. The spectra are consistent with a continuous solid solution involving octahedral sites randomly occupied by Al and Co. It is possible that the unusual Al shifts seen for this compound are related to the Van-Vleck susceptibility of this compound. 

The breakthrough was achieved by D. A. Evans and coworkers " , who demonstrated that aryldimethylphosphine-borane complexes 195 are easily deprotonated by i-BuLi/(—)-sparteine (11), furnishing efficient enantiotopic selection between the methyl groups (equation 45). The intermediate lithium compound 196 was added to benzophenone (to give alcohols 197) or oxidatively coupled to furnish bisphosphines 198 with high ee. The major amount of the minor diastereomer epi-196 is removed as separable meso- 9. ... 

Highly enantiomericaUy enriched lithium phosphides of type 204 were also prepared by oxidation of the lithium compounds 196 and oxidative degradation of the hydroxymethyl... 

Wet mixes are usually dried before calcination. Calcination is performed continuously in rotary or tunnel kilns, or batchwise in directly fired drum or box furnaces. The temperature at which the mixed metal oxide pigments are formed can be reduced by adding mineralizing agents [3.75]. In the case of chromium rutile pigments, addition of magnesium compounds [3.81] or lithium compounds [3.80] before calcination improves thermal stability in plastics. 

Enamels - [BARIUMCOMPOUNDS] (Vol3) - [ALUMINUMCOMPOUNDS - ALUMINIUMOXIDE(ALUMINA) - CALCINED,TABULAR, AND ALUMINATE CEMENTS] (Vol2) - [TIN COMPOUNDS] (Vol 24) -aluminum fluoride in [FLUORINE COMPOUNDS,INORGANIC - ALUMINUM](Vol 11) -antimony compds in [ANTIMONY COMPOUNDS] (Vol 3) -borate in [BORON COMPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] (Vol 4) -boric oxide in prepn of [BORON COMPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] (Vo 14) -lithium for [LITHIUM AND LITHIUM COMPOUNDS] (Vol 15)... 

Initiators -for acrylamide [ACRYLAMIDE POLYMERS] (Vol 1) -anionic initiators [INITIATORS - ANIONIC INITIATORS] (Voll4) -cationic initiators [INITIATORS - CATIONIC INITIATORS] (Vol 14) -in emulsion polymerization [LATEX TECHNOLOGY] (Vol 15) -for fluorocarbon elastomers [ELASTOMERS, SYNTHETIC - FLUOROCARBON ELASTOMERS] (Vol 8) -Free-radical initiators [INITIATORS - FREE-RADICAL INITIATORS] (Voll4) -organohthium compounds as [LITHIUM AND LITHIUM COMPOUNDS] (Vol 15) -peroxides as [PEROXIDES AND PEROXIDE COMPOUNDS - INORGANIC PEROXIDES] (Vol 18) -for propylene oxide [PROPYLENE OXIDE] (Vol 20) -for PUR polyols [POLYETHERS - PROPYLENE OXIDE POLYMERS] (Vol 19) -of suspension polymerization [ACRYLIC ESTER POLYMERS - SURVEY] (Vol 1)... 

Mansson 319) has also investigated the products of the reaction of poly(styryl)-lithium with oxygen. Although products with carbonyl and alcohol functionality were detected, they may have resulted from the column and thin layer chromatographic work-up procedures employed. In conclusion, the oxidation of polymeric organo-lithium compounds is complex, but the possibility of manipulating the reaction conditions to form useful macroperoxides and hydroperoxides is real, as evidenced by the work of Brossas and coworkers 350). 

Unless otherwise known, the toxicides of lithium organometallic compounds should be regarded as those of lithium compounds and of organometallic compounds in general. The latter were discussed in Section 12.4. Lithium oxide and hydroxide are caustic bases, and they may be formed by the combustion of lithium organometallic compounds or by their reaction with water. 

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