Rapid determination of microgram amounts of rhenium in solutions

Rhenium catalyzed interaction between sulfonitrazo R and tin(2) chloride in H2SO4-HNO3 mixture has been detected. The optimal conditions of the reaction have been defined. A method of determination of up to 1x10-5 g/l or 2.2x10-3 mol/l rhenium in process solutions in the presence of multiple excess of concomitant ions with spectrophotometric indication has been elaborated. It takes 8-10 min to conduct the analysis, Sr=0.13 (for 4.4x10-9 mol/l rhenium). The method can be employed for automated modes and as a test-method in the course of visual drop-photometric determination of rhenium. Refs. 11, figs. 3, tabs. 2