Extraction of Dissolved Inorganic Carbon (DIC) from Seawater Samples at CEDAD: Results of an Intercomparison Exercise on Samples from Adriatic Sea Shallow Water

Abstract

A dedicated sample processing line for the extraction of dissolved inorganic carbon (DIC) from seawater and groundwater for accelerator mass spectrometry (AMS) radiocarbon analysis has been developed at CEDAD, the Center for Dating and Diagnostic of the University of Salento, Lecce, Italy. The features of the new system are presented together with tests carried out to determine its functionality and background levels. The first results obtained at CEDAD for analyzing seawater samples taken from the Northern Adriatic compare well with results obtained for the same samples analyzed at ETH Zurich.

Radiocarbon Dating of Marine Samples: Methodological Aspects, Applications and Case Studies

“…This can be seen in Figure 3 which shows that the 14 C concentration in the marine pool is systematically lower than in the coeval atmosphere while high frequency fluctuations components are damped [14]. Figure 4 shows the comparison between the 14 C concentration measured in the atmosphere [16] and in Dissolved Inorganic Carbon (DIC) extracted from shallow water sampled from the Northern Adriatic Sea in 2010 at depth ranging from 14 to 30 m [17]. It can be immediately seen that sea water is depleted in 14 C concentration when compared with the atmosphere.…”

Estimation of Groundwater Residence Time Using Radiocarbon and Stable Isotope Ratio in Dissolved Inorganic Carbon and Soil CO2

“…A schematic diagram for the extraction of DIC from water is shown in Figure 3. The extraction system was modified from some existing techniques (e.g., Carmi et al 2007;Macchia et al 2013;Ge et al 2016;Takahashi et al 2021). About 10 mL commercial orthophosphoric acid (85%) was taken in a flask of ∼1 L capacity and was evacuated to ∼1 × 10 -2 mbar.…”