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AMCALI METAI _ „ TRENDS
MARKETS
Alkali Metals Moving Ahead With reserves considered adequate, sodium, lithium, potassium need expanded production facilities NEW ORLEANS-"Future trends for the alkali metals are all upward, particularly in the cases of sodium and lithium," claims Marshall Sittig of Ethyl Corp. Present availability of each alkali metal will meet demands adequately; however, continuously increasing demands call for a steady expansion of known reserves and of manufacturing facilities. Significant research and development continues on manufacturing processes for the alkali metals, continued Sittig at an American Institute of Chemical Engineers meeting. Stimuli for such research and development comes from: • Broadening markets. • Desire for lower manufacturing costs. • Possible direct use of alkali metal alloys in processing. By-passing metal manufacture thus suggests new electrolytic cell designs. • Local electrical power shortages suggesting a trend to thermochemical processes under some conditions. • Lithium Production. Military requirements have imposed limitations on production information, but maximum lithium metal production capacity in 1955 was estimated near 400,000 pounds. Now most lithium metal is produced by electrolysis of lithium chloride, indicates Sittig. The big problem in lithium production is extraction of its minerals from ores—usually silicates—and conversion to the chloride. Lithium-containing minerals are recovered by either froth flotation, sink-float separation, or hand picking. After roasting widi either limestone or sulfuric acid, the salt is dissolved in water and reacted or precipitated with other materials to form various lithium compounds. A Geological Survey bulletin indicates present mining and concentration techniques now used lose a significant portion, perhaps one third, of lithium in ores. A new process consists of roasting the ore with calcium chloride at 1500° to 1900* F. and recovering the lithium chloride produced in aqueous solution. Then, the high solubility of lithium salts 3288
C&EN
JULY
2.
1956
in organic solvents such as pyridine ancd amyl alcohol suggests possibilities fowr solvent extraction of lithium from othear ions, says Sittig. However, problems of ore concenttration technique will keep lithium th«e most expensive of the more widely usecd alkali metals. Specific and uniqu«e uses will have to compensate for this price disadvantage. • Na and K. Sodium's low prioe plus increased handling knowledge re>sulting from atomic energy work hav
