METHOD OF QUANTITATIVE DETERMINATION OF CONTENT OF LITHIUM IN ALLOY

摘要

FIELD: chemistry of lithium and its alloys; analytical methods of determination of content of lithium; quantitative determination of content of lithium in lithium-boron alloy. ^ SUBSTANCE: proposed method includes determination of initial mass of alloy specimen, heating the alloy specimen under test till separation of free lithium; mass of alloy specimen is determined in inert gas atmosphere; alloy specimen is heated to temperature not below sublimation temperature of pure lithium in vacuum at residual pressure not exceeding 1.10-6 atm; degree of rarefaction in closed space where heating is carried out is checked continuously; abrupt change in angle of inclination of branch of graph of change of specimen mass versus time of extraction of free lithium is indicative of complete distillation of free lithium; quantitative determination of content of free lithium is performed taking into account difference in mass of initial specimen of alloy and mass of specimen recorded at moment of attaining complete extraction of free lithium; specimen of alloy is heated in crucible made from inert refractory material; specimen is loaded into evaporating tube made from inert metal and placed in cavity of evaporating-condensing unit of distillation plant; its inner walls are made from quartz glass. Proposed method may be used for determination of free lithium contained in alloy in chemically unbound state. ^ EFFECT: enhanced accuracy of determination; reduction of time required for conducting process. ^ 2 dwg, 1 ex