Synthetic Humic Acid Model Substances with Specific Functional Properties for the Use in Complexation and Sorption Experiments with Actinides

In order to improve the knowledge about the interaction processes between humic acids (HA) and metal ions, e.g., actinide ions, various HA model substances with different functional properties were developed at FZR-IfR. These include synthetic HA with different functional group contents and various structural elements, chemically modified HA with blocked phenolic OH groups as well as 14C-labeled HA. Since start of the project, synthetic HA with distinct redox functionalities are developed.
The report gives an overview about the synthesis, characterization and application of HA with various functional properties. It describes the synthesis and characterization of the melanoidin-based HA type M1 and M42, which are characterized by different carboxyl group contents. In addition, the synthesis and characterization of modified HA with blocked phenolic OH groups as well as of HA with distinct redox functionalities are discussed.