The adsorption characteristics of helium on different activated carbons at 4.5-77 K

Abstract A crucial step in the development of helium isotope gas separation technology using adsorbents is the evaluation of the adsorption properties of different materials. In this study, a self-constructed cryostat was employed to establish the helium adsorption characteristics of several commercially available activated carbon. Experiments were conducted on two samples in the temperature-pressure range (4.5-77 K, 0.1 -1.0 MPa). The results showed that the coconut shell activated carbon had better helium adsorption capacity than coal activated carbon. The characterization parameters such as total BET surface area of these two activated carbons in this study were similar, while differences in adsorption isotherms were likely due to variations in micropore distribution and proportions. More types of adsorbents such as MOFs are to be tested.