Investigating tantalum(5) reaction with chromethylpyrazole

Chromoethylpyrazol forms ion associates with hexafluorotantalate ion at pH3-4 which is extracted into organic solvents (lambdasub(max)=590 nm). Optimal conditions for the reaction between chromoethylpyrazol and tantalum have been chosen oxalate moderately acid solutions (pH 3-4), 4,8x10-4 M in the dye and 1.3x10-1 M in fluoride ion. The extracted associate composition (RTaF6) has been determined by spectrophotometric, infrared, and chemical studies. The molar absorptivity of the associate is 9.1x104. An extraction-photometric procedure has been worked out of determining tantalum in niobium metal ferroniobium, niobium alloys, slags and pumices, simple and alloyed steel, melts of titanium production