Technetium retention by gamma alumina nanoparticles and the effect of sorbed Fe2+

Mayordomo, Natalia; Rodríguez, Diana M.; Schild, Dieter; Molodtsov, Konrad; Johnstone, Erik V.; Hübner, René; Azzam, Salim Shams Aldin; Brendler, Vinzenz; Müller, K.

doi:10.1016/j.jhazmat.2020.122066

Cited by 14 publications

(7 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Both solid samples were studied by Raman microscopy, with a second batch of the solid obtained at pH 2.0 also being analyzed using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM−EDX) and X-ray photoelectron spectroscopy (XPS). Experimental conditions for Raman measurements 35 and for SEM−EDX and XPS 15 are described elsewhere and detailed in the Supporting Information.…”

Section: Methodsmentioning

confidence: 99%

Exploring the Reduction Mechanism of⁹⁹Tc(VII) in NaClO₄: A Spectro-Electrochemical Approach

et al. 2022

Self Cite

View full text Add to dashboard Cite

Technetium (Tc) is an environmentally relevant radioactive contaminant whose migration is limited when Tc(VII) is reduced to Tc(IV). However, its reaction mechanisms are not well understood yet. We have combined electrochemistry, spectroscopy, and microscopy (cyclic voltammetry, rotating disk electrode, X-ray photoelectron spectroscopy, and Raman and scanning electron microscopy) to study Tc(VII) reduction in noncomplexing media: 0.5 mM KTcO 4 in 2 M NaClO 4 in the pH from 2.0 to 10.0. At pH 2.0, Tc(VII) first gains 2.3 ± 0.3 electrons, following Tc(V) rapidly receives 1.3 ± 0.3 electrons yielding Tc(IV). At pH 4.0−10.0, Tc(IV) is directly obtained by transfer of 3.2 ± 0.3 electrons. The reduction of Tc(VII) produced always a black solid identified as Tc(IV) by Raman and XPS. Our results narrow a significant gap in the fundamental knowledge of Tc aqueous chemistry and are important to understand Tc speciation. They provide basic steps on the way from non-complexing to complex media.

show abstract

Section: Methodsmentioning

confidence: 99%

Exploring the Reduction Mechanism of⁹⁹Tc(VII) in NaClO₄: A Spectro-Electrochemical Approach

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…This work aims to analyze Cd immobilization in γ-Al 2 O 3 nanoparticles and in mixtures of FEBEX smectite and γ-Al 2 O 3 nanoparticles with a combined experimental and theoretical approach. Both sorbents were selected because of their ubiquity and their good cation sorption capabilities (γ-Al 2 O 3 nanoparticles [34,35] and FEBEX smectite [14,[36][37][38][39]). Cd sorption on γ-Al 2 O 3 nanoparticles, and in mixtures of smectite and γ-Al 2 O 3 nanoparticles was studied in a wide range of pH values (3.0-11.0), Cd concentrations (from 1•10 −10 to 1•10 −3 M), Cl − concentrations (0, 1•10 −8 , and 1•10 −3 M), ionic strengths (from 5•10 −4 to 1•10 −1 M), and mixture composition (from 0% γ-Al 2 O 3 nanoparticles to 100% γ-Al 2 O 3 nanoparticles).…”

Section: Introductionmentioning

confidence: 99%

Cadmium Sorption on Alumina Nanoparticles and Mixtures of Alumina and Smectite: An Experimental and Modelling Study

Mayordomo,

Missana,

Alonso

2023

Minerals

Self Cite

View full text Add to dashboard Cite

Cadmium (Cd) is one of the most toxic transition metals for living organisms. Thus, effective measures to remediate Cd from water and soils need to be developed. Cd immobilization by alumina and mixtures of alumina and smectite have been analyzed experimentally and theoretically by sorption experiments and sorption modelling, respectively. Removal of aqueous Cd was dependent on pH and Cd concentration, being maximal for pH > 7.5. A two-site non-electrostatic sorption model for Cd sorption on alumina was developed and it successfully reproduced the experimental Cd immobilization on alumina. Cd sorption on mixtures of alumina and smectite were depending on pH, ionic strength, and alumina content in the mixture. Cd removal in mixtures increased with alumina content at high pH and ionic strength values. However, Cd sorption decreased with increasing alumina content under acidic conditions and low ionic strength. This effect was the result of alumina dissolution and the release of Al3+ into the suspension at low pH values. Modelling of Cd sorption on mixtures of alumina and smectite was performed by considering the individual Cd sorption models for alumina and smectite. It could be shown that the contributions of the individual sorption models were additive in the model for the mixtures when the competition of Al3+ with Cd2+ for cation exchange sites in smectite was included.

show abstract

“…Under these scenarios, the 98 Mo or 235 U targets are irradiated with a neutron source, such as a nuclear reactor, and form 99 Mo via 98 Mo(n,γ) 99 Mo or 235 U (n, fission) 99 Mo (~6% fission yield), respectively. The generated 99 Mo being sent to a processor is isolated, refined, and loaded onto a column, where Tc retention is negligible, such as alumina (Al 2 O 3 ) [ 4 ], and fixed in a portable generator for subsequent distribution. At the receiving end, whether it be a nuclear pharmacy or a hospital, the 99m Tc is eluted from the generator, compounded, and delivered to the point of use where it is administered to a patient.…”

Section: Introductionmentioning

confidence: 99%

Fusion-Based Neutron Generator Production of Tc-99m and Tc-101: A Prospective Avenue to Technetium Theranostics

Mausolf¹,

Johnstone²,

Mayordomo

et al. 2021

Pharmaceuticals

Self Cite

View full text Add to dashboard Cite

Presented are the results of 99mTc and 101Tc production via neutron irradiation of natural isotopic molybdenum (Mo) with epithermal/resonance neutrons. Neutrons were produced using a deuterium-deuterium (D-D) neutron generator with an output of 2 × 1010 n/s. The separation of Tc from an irradiated source of bulk, low-specific activity (LSA) Mo on activated carbon (AC) was demonstrated. The yields of 99mTc and 101Tc, together with their potential use in medical single-photon emission computed tomography (SPECT) procedures, have been evaluated from the perspective of commercial production, with a patient dose consisting of 740 MBq (20 mCi) of 99mTc. The number of neutron generators to meet the annual 40,000,000 world-wide procedures is estimated for each imaging modality: 99mTc versus 101Tc, D-D versus deuterium-tritium (D-T) neutron generator system outputs, and whether or not natural molybdenum or enriched targets are used for production. The financial implications for neutron generator production of these isotopes is also presented. The use of 101Tc as a diagnostic, therapeutic, and/or theranostic isotope for use in medical applications is proposed and compared to known commercial nuclear diagnostic and therapeutic isotopes.

show abstract

Technetium retention by gamma alumina nanoparticles and the effect of sorbed Fe2+

Cited by 14 publications

References 49 publications

Exploring the Reduction Mechanism of⁹⁹Tc(VII) in NaClO₄: A Spectro-Electrochemical Approach

Exploring the Reduction Mechanism of⁹⁹Tc(VII) in NaClO₄: A Spectro-Electrochemical Approach

Cadmium Sorption on Alumina Nanoparticles and Mixtures of Alumina and Smectite: An Experimental and Modelling Study

Fusion-Based Neutron Generator Production of Tc-99m and Tc-101: A Prospective Avenue to Technetium Theranostics

Contact Info

Product

Resources

About

Technetium retention by gamma alumina nanoparticles and the effect of sorbed Fe2+

Cited by 14 publications

References 49 publications

Exploring the Reduction Mechanism of99Tc(VII) in NaClO4: A Spectro-Electrochemical Approach

Exploring the Reduction Mechanism of99Tc(VII) in NaClO4: A Spectro-Electrochemical Approach

Cadmium Sorption on Alumina Nanoparticles and Mixtures of Alumina and Smectite: An Experimental and Modelling Study

Fusion-Based Neutron Generator Production of Tc-99m and Tc-101: A Prospective Avenue to Technetium Theranostics

Contact Info

Product

Resources

About

Exploring the Reduction Mechanism of⁹⁹Tc(VII) in NaClO₄: A Spectro-Electrochemical Approach

Exploring the Reduction Mechanism of⁹⁹Tc(VII) in NaClO₄: A Spectro-Electrochemical Approach