The AIMD simulations highlight the significant role of protons and Li⁺ ions in governing the diffusion of C2H4 and C2H6 in H-SAPO-RHO and Li-SAPO-RHO frameworks. In all cases, C2H6 diffuses more slowly than C2H4. Moreover, any modification of the AlPO framework to incorporate Si atoms with compensating protons or Li + ions increases the activation energy for C2H6 diffusion.