The facilitated transport of Cr(VI) through a bulk liquid membrane (BLM) is investigated, using the by p-tert-butylcalix[4]-arene amine derivative as mobile carrier. The transport ef.ciency of Cr(VI) by p-tert-butylcalix[4]arene amine derivative was investigated under various experimental conditions such as the in.uence of pH on the donor and the acceptor phase, effect of Cr(VI) and carrier concentration, the type of solvent, the stirring speed, and the temperature. The kinetic parameters (k1, k2, Rmaxm, tmax, Jmaxd, Jmaxa) were calculated for the interface reactions assuming two consecutive, irreversible first order reactions. The activation energy values are calculated as 5.94 and 12.51 kJ mol-1 for extraction and reextraction, respectively. The values of the calculated activation energy indicate that the process is diffusionally controlled by species. © Taylor & Francis Group, LLC.