Helium separation from gas mixtures using a temperature-regulated trapdoor zeolite

Abstract

Alternative methods of recovering helium from natural gas such as adsorption processes are often more cost-effective than cryogenic distillation approaches for small-scale reserves. However, conventional adsorbents tend to selectively adsorb bulk components like nitrogen and methane rather than the minor helium component, increasing overall gas production costs. Here, we show that a trapdoor potassium chabazite, K-CHA can selectively capture helium from a helium‐nitrogen mixture. Isobaric measurements of helium adsorption capacities on K-CHA were found to exhibit a distinctive bell shape indicative of a trapdoor guest admission rather than a monotonic increase of adsorption capacity with dec..