Sorption of Nitrogen-16 on Graphite

Abstract

IN the course of experiments designed to determine the specific activity of nitrogen-16 in the carbon dioxide coolant of a Calder Hall nuclear reactor, it was discovered that this nuclide is adsorbed on various surfaces in the presence of overwhelmingly large concentrations of the carbon dioxide carrier gas. Adsorption occurred at room temperature on copper, iron, rust and graphite, being strongest on the last two materials. Sorption on to aluminium and polythene was negligible. The present communication describes preliminary experiments to establish the basic nature of the adsorption process. In these experiments a graphited surface, such as is common within a nuclear reactor, was chosen as adsorbent.