High temperature pyrolysis to extract 36Cl for Accelerator Mass Spectrometry measurements

Abstract 36 Cl and stable Cl were extracted from solids by high temperature pyrolysis and then analyzed by Accelerator Mass Spectrometry (AMS). Cl was quantitatively extracted from rock, ore, vegetation and freshwater sediments in samples weighing from 100 mg to 2 g. 36 Cl:Cl activity ratios measured following Cl extraction by pyrolysis agreed with those measured following Cl extraction by acid leaching. The simple pyrolysis extraction has the additional advantages that stable Cl − can be measured on the same sample along with other anions, the 36 Cl:Cl ratio can be adjusted by diluting the known Cl − concentration in the collection solution to control the activity of 36 Cl in the target and the potential interference of 36 S can also be assessed prior to the AMS measurements.