Porträt Prof. Dr. Brendler, Vinzenz; FWOA

Prof. Dr. Vinzenz Brendler

Head of Department
Thermo­dynamics of Actinides
Phone: +49 351 260 2430

Further Development of the Smart Kd-Concept for Long-Term Safety Assessment (WEIMAR)

Financed by:
German Federal Ministry of Economic Affairs and Energy (BMWi) under Contract Nos. 02 E 11072B
Funding period:
2012/07/01 – 2016/11/30
Cooperation Partner:
GRS - Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) gGmbH Braunschweig
Vinzenz Brendler, Madlen Stockmann
Constanze Richter


One important natural retardation process for contaminants (e.g. heavy metals, radionuclides) during the transport through surface sediments or rock fissures is sorption onto mineral surfaces. Describing the sorption as realistically as possible is therefore essential in geochemical modeling.

In this project, a new modeling approach is developed, where more realistic distribution coefficients are calculated as a function of important environmental parameters such as pH value, ionic strength, competing cations and complex forming ligands using PHREEQC [1] and UCODE [2]. Such a mechanistic approach, namely “Smart Kd concept” based on surface complexation models (SCM) and allows to predict variation in sorption as a consequence of changing physicochemical conditions (e.g. due to anthropogenic causes or climatic changes). Required thermodynamic sorption data are taken from RES³T.

The philosophy behind this approach is to compute a-priori multidimensional smart Kd-matrices for relevant contaminants (see Fig. 1), which are accessible during (reactive) transport simulations with existing transport codes (e.g. such as the 3D reactive transport code r³t, radionuclides, reaction, retardation, and transport [3] as well as its update d³f++). It is worth mentioning that this basic methodology can be transferred to any other transport code relying on conventional distribution coefficients as well as to any geological formation.

smart-kd matrix

Fig. 1.: Multidimensional smart Kd-matrix for U(VI) sorption in a sandy aquifer system as a function of pH, [DIC], and [Ca] (d in m3 kg-1, logarithmic scale).

  1. Parkhurst, D.L.; Appelo, C.A.J. (1999) U.S.G.S. Report 99-425.
  2. Poeter, E.P. et al. (2005) U.S.G.S. Techniques and Methods 6-A11.
  3. Fein, E. (2004) Report GRS-192.


Journal papers:

Macroscopic and spectroscopic characterization of uranium(VI) sorption onto orthoclase and muscovite and the influence of competing Ca2+

Richter, C.; Müller, K.; Drobot, B.; Steudtner, R.; Großmann, K.; Stockmann, M.; Brendler, V.

Smart Kd-values, their uncertainties and sensitivities - Applying a new approach for realistic distribution coefficients in geochemical modeling of complex systems

Stockmann, M.; Schikora, J.; Becker, D.-A.; Flügge, J.; Noseck, U.; Brendler, V.

Conference contributions (Oral presentations and posters):

Sensitivity and uncertainty analysis for geochemical models for repository safety assessment

Stockmann, M.; Becker, D.-A.; Noseck, U.; Brendler, V.

  • Poster
    Ninth International Conference on Sensitivity Analysis of Model Output (SAMO'19), 28.-30.10.2019, Barcelona, Spain

Smart Kd‑concept for realistic description of sorption processes

Stockmann, M.; Becker, D.; Flügge, J.; Schikora, J.; Noseck, U.; Brendler, V.

  • Lecture (Conference)
    DAEF 2016 - 2nd Conference on Key Topics in Deep Geological Disposal – Challenges of a Site Selection Process: Society – Procedures – Safety, 26.-28.09.2016, Köln, Deutschland

Multidimensional “smart Kd-matrices” for realistic description of sorption processes

Stockmann, M.; Brendler, V.; Flügge, J.; Noseck, U.

  • Lecture (Conference)
    Water-Rock Interaction, 16.-21.10.2016, Évora, Portugal

Mechanistic sorption models: Species, Thermodynamic, Application

Bok, F.; Richter, C.; Stockmann, M.; Brendler, V.

  • Invited lecture (Conferences)
    American Chemical Society Spring meeting, 13.-17.03.2016, San Diego, USA

Sorption of environmentally relevant radionuclides (U(VI), Np(V)) and lanthanides (Nd(III)) on feldspar and mica

Richter, C.

  • Lecture (Conference)
    Kompetenzzentrum Ost für Kerntechnik (KOMPOST) 10.Doktorandenseminar, 08.12.2015, Dresden, Deutschland

Sorption of environmentally relevant radionuclides (UO22+, NpO2+) and lanthanides (Nd3+) on feldspar and mica

Richter, C.

  • Lecture (others)
    Abteilungsseminar der Abteilung Hydrogeochemie und Hydrogeologie, Institut für Geowissenschaften, Universität Heidelberg, 03.12.2015, Heidelberg, Deutschland

Influence of calcium on the uranium(VI) interaction with mineral surfaces

Richter, C.; Brendler, V.; Steudtner, R.; Drobot, B.

  • Poster
    GDCh Wissenschaftsforum 2015, 30.08.-02.09.2015, Dresden, Deutschland

Influence of calcium onto the sorption of uranium(VI) in the far-field of nuclear waste repositories

Richter, C.

  • Lecture (Conference)
    Petrus PhD Conference 2015, 22.-26.06.2015, Nancy, France

A new methodology for utilizing multidimensional smart Kd-matrices in transport programs for long-term safety assessment

Stockmann, M.; Brendler, V.; Schikora, J.; Flügge, J.; Noseck, U.

  • Lecture (Conference)
    MIGRATION 2015, 13.-18.09.2015, Santa Fe, NM, USA

Investigation of contaminated soil

Richter, C.; Fahmy, K.

  • Lecture (Conference)
    ISBC Meeting, Lund 2014, 03.06.2014, Lund, Schweden

The influence of naturally occurring microorganisms on the sorption of uranium

Richter, C.

  • Lecture (others)
    LLNL intern seminar, 23.-24.06.2014, Livermore, USA

The Influence of Mineral-Originated Microorganisms on the Sorption of Uranium

Richter, C.; Großmann, K.; Brendler, V.

  • Poster
    Goldschmidt 2014, 09.-13.06.2014, Sacramento, USA

Sorption data: Ways from a plain collection to recommended values

Bok, F.; Richter, A.; Brendler, V.

  • Invited lecture (Conferences)
    248th ACS National Meeting, 10.-14.08.2014, San Francisco, USA

New Methodology for Realistic Integration of Sorption Processes Safety Assessments

Noseck, U.; Britz, S.; Flügge, J.; Mönig, J.; Brendler, V.; Stockmann, M.

  • Lecture (Conference)
    WM2014 Conference, 02.-06.03.2014, Phoenix, Arizona, USA

A wrap up of modeling sorption processes of Eu3+ under varying geochemical conditions

Britz, S.; Noseck, U.; Brendler, V.; Durner, W.; Zachmann, D.

  • Lecture (Conference)
    TRePro III – Workshop on Modelling of Coupled Reactive and Transport Processes, 05.-07.03.2014, Karlsruhe, Deutschland

Titration curves, column experiments, and reactive transport models

Britz, S. M.; Noseck, U.; Brendler, V.; Stockmann, M.

  • Poster
    Goldschmidt 2013, 25.-30.08.2013, Florence, Italy

Environmental parameters that determine distribution coefficients of radionuclides for repositories

Stockmann, M.; Brendler, V.; Richter, C.; Flügge, J.; Britz, S.; Noseck, U.

  • Poster
    Goldschmidt 2013, 25.-30.08.2013, Florence, Italy

Clarification of the sorption behavior of uranium onto mica and feldspar

Richter, C.; Stockmann, M.; Brendler, V.; Großmann, K.

  • Poster
    JCF Frühjahrssymposium 2013, 06.-09.03.2013, Berlin, Deutschland