The Radioactive tracer lab is used for the extraction of sulfur species from sediment and rock samples. Specialized glassware is available for the separation of acid volatile sulfur (AVS) and chromium reducible sulfur (CRS) using both cold and warm distillation procedures. Thode reduction for the conversion of solid sulfate into silver sulfide is also possible.
Current applications for these preparation steps are (1) the quantification of microbial sulfate reduction rates in natural samples by incubation with 35SO42-¬¬ radiotracer, and (2) measurement of stable sulfur isotope ratios (δ34S) in sulfide minerals.
The laboratory is the designated area to work with radioactive 35S (-emitter with 87.2 days half-life) at the Department of Earth Science.
Photo: cold chromium reduction set-up for the distillation of H235S from incubated sediments