A spectroscopic study of the complexation reaction of trivalent lanthanides with a synthetic acrylate based PCE-superplasticizer

Fröhlich, Daniel R.; Koke, Carsten; Maiwald, Martin; Chomyn, Claudia; Plank, Johann; Panak, Petra J.

doi:10.1016/j.saa.2018.09.025

Cited by 5 publications

(1 citation statement)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the last few years, the complexation properties of trivalent actinides [An(III)) and lanthanides (Ln(III)] with model systems like oxalate, malonate, or succinate and with commercially available super plasticizers have been studied extensively. − However, thermodynamic data for pentavalent actinides (An V O 2 + ) are scarce.…”

Section: Introductionmentioning

confidence: 99%

Complexation of Np(V) with the Dicarboxylates, Malonate, and Succinate: Complex Stoichiometry, Thermodynamic Data, and Structural Information

et al. 2021

Self Cite

View full text Add to dashboard Cite

The complexation of Np(V) with malonate and succinate is studied by different spectroscopic techniques, namely, attenuated total reflection Fourier transform infrared (ATR FT-IR) and extended X-ray absorption fine-structure (EXAFS) spectroscopy, as well as by quantum chemistry to determine the speciation, thermodynamic data, and structural information of the formed complexes. For complex stoichiometries and the thermodynamic functions (log β n °(Θ), ΔrH n °, ΔrS n °), near infrared absorption spectroscopy (vis/NIR) is applied. The complexation reactions are investigated as a function of the total concentration of malonate ([Mal2–]total) and succinate ([Succ2–]total), ionic strength [I m = 0.5–4.0 mol kg–1 Na+(Cl–/ClO4 –)], and temperature (Θ = 20–85 °C). Besides the solvated NpO2 + ion, the formation of two Np(V) species with the stoichiometry NpO2(L) n 1–2n (n = 1, 2, L = Mal2–, Succ2–) is observed. With increasing temperature, the molar fractions of both complex species increase and the temperature-dependent conditional stability constants log β n ′(Θ) at given ionic strengths are determined by the law of mass action. The log β n ′(Θ) are extrapolated to IUPAC reference-state conditions (I m = 0) according to the specific ion interaction theory (SIT), revealing thermodynamic log β n °(Θ) values. For all formed complexes, [NpO2(Mal)−: log β1 °(25 °C) = 3.36 ± 0.11, NpO2(Mal)2 3–: log β2 °(25 °C) = 3.95 ± 0.19, NpO2(Succ)−: log β1 °(25 °C) = 2.05 ± 0.45, NpO2(Succ)2 3–: log β2 °(25 °C) = 0.75 ± 1.22], an increase of the stability constants with increasing temperature was observed. This confirmed an endothermic complexation reaction. The temperature dependence of the log β n °(T) values is described by the integrated Van’t Hoff equation, and the standard reaction enthalpies and entropies for the complexation reactions are determined. Furthermore, the sum of the specific binary ion–ion interaction coefficients Δεn °(Θ) for the complexation reactions are obtained as a function of the t from the respective SIT modeling as a function of the temperature. In addition to the thermodynamic data, the structures of the complexes and the coordination modes of malonate and succinate are investigated using EXAFS spectroscopy, ATR-FT-IR spectroscopy, and quantum chemical calculations. The results show that in the case of malonate, six-membered chelate complexes are formed, whereas for succinate, seven-membered rings form. The latter ones are energetically unfavorable due to the limited space in the equatorial plane of the Np(V) ion (as NpO2 + cation).

show abstract

Section: Introductionmentioning

confidence: 99%

Complexation of Np(V) with the Dicarboxylates, Malonate, and Succinate: Complex Stoichiometry, Thermodynamic Data, and Structural Information

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

Radiolysis effect on Eu(III)-superplasticiser interactions in artificial cement and squeezed cement pore waters

Legand

Macé

Muzeau

et al. 2023

Journal of Hazardous Materials

View full text Add to dashboard Cite

The complexation of Eu(III) and Cm(III) with polyacrylate as a model compound for complex polycarboxylates studied by laser fluorescence spectroscopy

Fröhlich

Panak

2019

Journal of Luminescence

Self Cite

View full text Add to dashboard Cite

The complexation of the trivalent heavy metals Eu(III) and Cm(III) with polyacrylate as a model ligand is investigated by time-resolved laser fluorescence spectroscopy (TRLFS) and subsequent thermodynamic modelling (charge neutralization model). The aqueous speciation of both metals is investigated as a function of temperature (20-60°C) and ligand concentration (0-0.4 g/kg) in 0.1 mol/kg NaCl solution ([H + ] total ≈ 10 −4 mol/kg). Only one complex species is observed at all experimental conditions. With increasing temperature the aqueous Eu(III) and Cm(III) speciation is slightly shifted towards the complexes species. This effect is attributed to the stronger deprotonation of the polymer, which is also reflected by an increase of its loading capacity. The complex stability constants, however, show no visible temperature dependency. Log β'(T) ranges between 5.8 and 5.9 for both Eu(III) and Cm(III) over the whole range of experimental conditions.

show abstract

A spectroscopic study of the complexation reaction of trivalent lanthanides with a synthetic acrylate based PCE-superplasticizer

Cited by 5 publications

References 15 publications

Complexation of Np(V) with the Dicarboxylates, Malonate, and Succinate: Complex Stoichiometry, Thermodynamic Data, and Structural Information

Complexation of Np(V) with the Dicarboxylates, Malonate, and Succinate: Complex Stoichiometry, Thermodynamic Data, and Structural Information

Radiolysis effect on Eu(III)-superplasticiser interactions in artificial cement and squeezed cement pore waters

The complexation of Eu(III) and Cm(III) with polyacrylate as a model compound for complex polycarboxylates studied by laser fluorescence spectroscopy

Contact Info

Product

Resources

About