-Sample measurements in less than one hour, producing a higher number of dating analyses per day than conventional methods (higher productivity). All these advantages are due to the fact that in the traditional procedures, the radiation emitted by 14C is measured, but with AMS, we measure the total number of 14C atoms that are contained in the sample.
For radiocarbon measurements with accelerator mass spectrometry (AMS) at CNA solid graphite targets are required. Samples in the laboratory are therefore cleaned, and intrinsic carbon is extracted to be transformed in such material. In a general way, carbon is extracted as CO2 and is reduced to graphite with a graphitization system.
The Automated Graphitization Equipment (AGE) features a graphitization that is directly coupled to the sample combustion in an elemental analyzer (EA). AGE has been developed for fast and efficient sample preparations for radiocarbon measurement by means of accelerator mass spectrometry.
Traditionally, the cryogenic transport of CO2 into the graphitization reactors with liquid nitrogen is used after sample combustion. AGE uses instead a column filled with zeolite to trap the CO2 coming from the combustion in the EA. The CO2 can then be easily released by heating the zeolite trap and transferred to the reactor by gas expansion. The consequence of the AGE avoiding the use of liquid nitrogen is, that it is very compact and allows running fully automated for sample combustion and graphitization.
The new Carbonate Handling System (CHS) to obtain CO2 from carbonate samples is also coupled to AGE, but generates CO2 by acid dissolution instead of combustion. It uses an autosampler that purges the septum tubes in which the samples are stored, adds the acid, and transports the generated CO2 to the reactors.
The entire system with valves, ovens, temperature and pressure sensors is computer controlled. A LabVIEW program runs through all consecutive steps when processing a sample: catalyst preconditioning, sample combustion in the EA and CO2 trapping, thermal CO2 release from the trap into the reactor, and finally the graphitization reaction itself.