Effect of Chloride Ions on the Hydrolysis of Trivalent Lanthanum, Praseodymium and Lutetium in Aqueous Solutions of 2 M Ionic Strength

Spectrophotometric Determination of the First Hydrolysis Constant of Praseodymium (III)

“…[Pr(III)] total = 0.00086 M. Statistical comparison of the -log*β 1 estimators with the value obtained potentiometrically and reported in the literature by López-González et al [12] are also shown, following Miller and Miller [24], at a significance level of 95%.…”

“…The computer program SQUAD [13] was used to determine the first hydrolysis constant of Pr(III), as well as to compare it with the previously calculated with the potentiometric method [12]. The data range used as input for the program SQUAD was selected as follows: The initial point was taken after the excess acid was neutralized and the end point was selected just before Pr(OH) 3(s) precipitation started, according to the first derivative Figure 3b and in range the absorbance values between 0.05 to 1.5.…”

“…The reaction of Pr(III) with water has been studied in several works. The most usual method has been the potentiometric [4][5][6][8][9][10][11][12]. Only one work has used solvent extrac- Table 2.…”

“…Essential information on actinide chemistry in ground water is lacking. The hydrolysis of praseodymium has been studied by several methods [3][4][5][6][7][8][9][10][11][12]. However, the data are different, because of experimental conditions employed such as different ionic strength, temperature, concentrations of the praseodymium and pH range.…”

“…There are only a few literature works about environments such as sea water, and others with higher ionic strength like brine (used in salt mines for radioactive waste storage); and that is the source of our interest in providing knowledge about hydrolysis constants in high ionic strength environments. Therefore, in this work the first hydrolysis constant of praseodymium was determined by spectrophotometric methods in the same condition with López-González, et al [12] because the IUPAC [21] recommends using two methods or more.…”