Salt cake , lithium

B. 2,6,6-Trimethyl-2,4-cyclohexadienone. In a nitrogen-filled dry box, 25.0 g. of lithium 2,6-dimethylphenoxide (0.195 mole) is transferred to an oven-dried, thick-walled Pyrex bomb tube (650 x 19 mm.). The bomb tube is stoppered with a rubber stopper fitted with a drying tube, removed from the dry box, and 75 ml. of methyl iodide (170 g., 1.20 moles) (freshly distilled from calcium hydride) is quickly pipetted into the bomb under a dry nitrogen stream. The bomb is cooled in a dry-ice bath and sealed with an oxygen torch. After warming to room temperature, the bomb is shaken to disperse the salt cake and placed in a bomb furnace which has been preheated to 135° (Note 7). 

Lithium Recovery. The melt used in this process is relatively inexpensive except for the lithium carbonate which comprises approximately 84% of the salt cost. Therefore it is desirable to recover the lithium from the process filter cakes. An aqueous process has been developed for this purpose. The filter cakes are slurried with water and filtered to extract the very soluble sodium and potassium carbonates lithium carbonate remains with the ash because it is relatively insoluble under these conditions. The ash-lithium carbonate cake is slurried in water and the lithium is solubilized by conversion to the bicarbonate. The ash is removed by filtration and the soluble bicarbonate in the filtrate is precipitated as the carbonate. The lithium carbonate is separated by filtration and returned to the process stream the saturated lithium carbonate filtrate is recycled to conserve lithium. Laboratory tests have demonstrated that more than 90% of the lithium can be recovered by this technique. 

Environmental Contains no heavy metals or other agents harmful to the environment ecologically inert pyrophosphate additive may affect aquatic life or cause algal blooms if released into rivers in Ig. quantities Precaution Avoid contact with strong min. acids or substances liable to decomp, by dust, e.g., peroxides avoid excessive moisture humidity or direct contact with water results in caking Hazardous Decomp. Prods. Lithium salts if prod. dec. by min. acid Storage Store under dry conditions seal container after use Laponite MS [Southern Clay Prods.]... 

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