Application of proton microprobe and C-12-Rutherford backscattering spectroscopy to the identification of Hg(II)-cations sorbed by granite minerals

The sorption of Hg(II)-cations from aqueous solutions by the three main min eral constituents of granite (quartz, feldspar and biotite) was investigate d using proton microprobe and C-12-RBS. The investigation also included bat ch-type sorption experiments using pulverized mineral crystals and Hg-203-l abelled solutions as well as high-resolution gamma-ray spectroscopy. The ba tch-type experiments as well as the microprobe elemental mappings and line- scans indicated that the phyllosilicate biotite shows the highest Hg(II)-ca tions uptake ability. On the other hand, the C-12-RBS data showed that the framework silicates feldspar and quartz adsorb small. amounts of Hg(II)-cat ions especially on their surface. The rock texture and the surface microtop ography of the minerals seem to play a crucial role in the migration of Hg( II)-cations into the granite.