TITLE:
An experimental study of hydrolytic behavior of thulium in basic and near-neutral solutions
AUTHORS:
S. A. Stepanchikova, R. P. Biteykina, A. A. Sava
KEYWORDS:
Rare Earth Elements; Thulium; Stability Constants; Spectrophotometry; pH-Indicators
JOURNAL NAME:
Open Journal of Inorganic Chemistry,
Vol.3 No.2,
April
30,
2013
ABSTRACT: Hydrolytic equilibria of Tm (III) in KOH solutions
were studied at 25°C. A
spectrophotometry with m-cresol
purple and 2-naphthol as pH indicators was used at an ionic strength of not
more than 0.0005. The results indicate that in freshly prepared solutions at pH
ranging between 6 and 10 Tm is present as , , and . The stepwise stability
constants of hydroxide complexes calculated at zero ionic strength were
obtained as coefficient of linear regression equations from the graph of optical
densities of the indicators in Tm solutions at varying pH.