Graphitization reaction via zinc reduction: How low can you go?

Abstract In a previous work, isotopic fractionation in the graphitization reaction for Radiocarbon Accelerator Mass Spectrometry ( 14 C-AMS) was evaluated for amounts of Zn ranging from 20 to 50 mg. The results have shown that a slightly lower variation in δ 3 C during graphitization was achieved with less Zn. In the present paper, assuming that low amounts of Zn would provide the best results, we go further and test isotopic fractionation for 0, 10 and 20 mg of Zn in the graphitization reaction. The results show that the use of 10 mg of Zn yields similar fractionation to that using 20 mg, while using only TiH 2 and no Zn produces the same scattering for amounts from 30 to 50 mg. The absence of Zn, on the other hand, plays a major role on the reaction yield for the tested conditions, limiting it to 50%.