Colorimetric determination of thorium with Methylthymol Blue.
Thorium forms with Methylthymol Blue (MTB) in alkaline medium (pH 9-10) a complex of the composition Th(MTB)(2), even in the presence of EDTA, which masks almost all metals against the reagent. This can be used for selective determination of traces of thorium (0.5-2.8 ppm) by measurement of the absorbance at 535 nm.
Adam
J
J
Institute of Geological Sciences Charles University, Prague, Czechoslovakia.
Pribil
R
R