Spectrophotometric microdetermination of bismuth in organic compounds after oxygen-flask combustion

A method has been developed for the micro and submicro determination of bismuth in organic compounds, based on combustion in an oxygen-filled flask, provided with a silica spiral instead of the conventional platinum holder (which alloys with bismuth). After absorption of the products in hydrochloric acid (1 + 1), the solution is chemically treated to convert the bismuth into the orange-yellow BiI − 4 complex, then the absorbance is measured at 465 nm. Analysis of 12 organic compounds containing 28–74% of bismuth yielded satisfactory results with a maximum standard deviation of 0.4%.