DETERMINATION OF TELLURIUM BP GAS-PHASE MOLECULAR ABSORPTION SPECTROMETRY AFTER HYDROGEN TELLURIDE GENERATION

A method for determination of tellurium(IV) or tellurium(VI) is descri bed that involves hydrogen telluride generation by reduction with sodi um tetrahydroborate(III), evolution of hydride with HCl solution, tran sport into a flow-cell placed in a UV-visible molecular absorption spe ctrophotometer and measurement of gas at 190 nm. Hydride generation an d determination procedures are optimized, based on height and area of absorbance versus time profile of hydrogen telluride generated. Using the best experimental conditions found the calibration curve is linear from 5 to 100 mu g/ml of tellurium, 1.1 mu g/ml of tellurium(IV) or 3 ,1 mu g/ml of tellurium(VI) can be detected, and relative standard dev iation ranges from 4 to 7%. The method is applied to the analysis of a dditives for synthetic rubber making.