Examination of the liquid scintillation cocktails for C-14 monitoring of exhaust

Nakajima, Junya ; Yamada, Katsunori; Yokoyama, Hiroya; Shishido, Nobuhito; Muto, Yasushi

We implement C-14 monitoring of exhaust in such a way as to measure mono-ethanolamine which is a collector of CO with a liquid scintillation counter. Since Aquasol-2, which we have used so far was finished selling, we have done technical examinations on Insta-Gel plus and Ultima Gold for the alternative cocktail of Aquasol-2. In the result, as for the both cocktails, we confirmed that mono-ethanolamine can merge into the cocktails with some chemical additive, and detection limits of C-14 can comply the law limit of C-14 concentration of exhaust. However, chemical luminescence of Ultima Gold was so intense that it might affect the measurement in the case of measuring H-3 at the same time. Because of this, we chose Insta-Gel plus as the alternative cocktail.