0000000000744116
AUTHOR
Anna Irto
Modeling the acid-base properties of molybdate(VI) in different ionic media, ionic strengths and temperatures, by EDH, SIT and Pitzer equations
This paper reports the results of a study on the determination of the protonation constants of MoO42 −, in NaClaq, NaNO3aq, KClaq, at different ionic strengths (0 < I/mol dm− 3 ≤ 5.0 in NaClaq, 0 < I/mol dm− 3 ≤ 3.0 in NaNO3aq and KClaq) and temperatures (278.15 ≤ T/K ≤ 318.15 in NaClaq, only 298.15 K in NaNO3aq and KClaq), by potentiometric (ISE-H+ glass electrode) and spectrophotometric (UV/Vis) titrations. After a critical analysis of results and literature findings, the proposed speciation model takes into account the formation of two monomeric and four heptameric species, namely: MoO4H−, MoO4H2, (MoO4)7H86 −, (MoO4)7H95 −, (MoO4)7H104 − and (MoO4)7H113 −. Due to the complexity of…
Understanding the Solution Behavior of Epinephrine in the Presence of Toxic Cations: A Thermodynamic Investigation in Different Experimental Conditions
The interactions of epinephrine ((R)-(&minus
The solution behavior of dopamine in the presence of mono and divalent cations: A thermodynamic investigation in different experimental conditions
The interactions of dopamine [2-(3,4-Dihydroxyphenyl)ethylamine, (Dop-)] with methylmercury(II) (CH3Hg+), magnesium(II), calcium(II), and tin(II) were studied in NaCl(aq) at different ionic strengths and temperatures. Different speciation models were obtained, mainly characterized by mononuclear species. Only for Sn2+ we observed the formation of binuclear complexes (M2L2 and M2LOH (charge omitted for simplicity)
Speciation Studies of Bifunctional 3-Hydroxy-4-Pyridinone Ligands in the Presence of Zn2+ at Different Ionic Strengths and Temperatures
The acid&ndash
Modelling the dependence on medium and ionic strength of molybdate acidbase properties, and its interactions with phytate
The importance of molybdenum from a biological, environmental and technological point of view is very well known since many decades [15]. In particular, it is mainly present in aqueous solutions as molybdate (MoO42), which is the biologically active form, entering in the cells by active transport systems. Though molybdate is the major species in neutral to basic pH conditions, at lower pH it undergoes protonation and, chiefly, polymerization, even at millimolar concentration levels [2]. Consequently, the modelling of its speciation and acidbase properties is not very simple, as demonstrated by the nonhomogeneity of available literature data. In this light, our group has started a systematic…
The Effect of Metal Cations on the Aqueous Behavior of Dopamine. Thermodynamic Investigation of the Binary and Ternary Interactions with Cd2+, Cu2+ and UO22+ in NaCl at Different Ionic Strengths and Temperatures
The interactions of dopamine [2-(3,4-Dihydroxyphenyl)ethylamine, (Dop−)] with cadmium(II), copper(II) and uranyl(VI) were studied in NaCl(aq) at different ionic strengths (0 ≤ I/mol dm−3 ≤ 1.0) and temperatures (288.15 ≤ T/K ≤ 318.15). From the elaboration of the experimental data, it was found that the speciation models are featured by species of different stoichiometry and stability. In particular for cadmium, the formation of only MLH, ML and ML2 (M = Cd2+; L = dopamine) species was obtained. For uranyl(VI) (UO22+), the speciation scheme is influenced by the use of UO2(acetate)2 salt as a chemical; in this case, the formation of ML2, MLOH and the ternary MLAc (Ac = acetate) species in a …