Experimental and modeling study of the aqueous solubility of vanadium(V) incorporated by solid solution in apatite phases

• Applicant: Dr. Frieder Enzmann, since 9/2022
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2020 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 445811061

To understand the elevated vanadium concentrations in aquifers of volcanic areas, and also the toxic effects of vanadium on the human skeletal system, the solubility products of the solid solutions between phosphate and vanadate apatite phases will be investigated. Both hydroxyapatite and fluorapatite series will be investigated. The synthesis of the mixed phosphate/vanadate apatites will be performed on the basis of a one-step aqueous method in alkaline media. Structural analysis of the phosphate substitution by vanadate will be performed using XRD and EXAFS analysis at a synchrotron facility. A theoretical interpretation of the data will be performed based on the solid-solution aqueous-solution equilibrium approach for the binary phosphate-vanadate apatite series using Lippmann equations, and also by using the Gibbs energy minimization code GEMS. The aim of this effort is to predict the vanadium solubility at any vanadium fraction incorporated in the apatite host phase.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Professor Dr.-Ing. Michael Kersten, until 9/2022