Retention of progesterone by four carbonaceous materials: study of the adsorption kinetics

The process by which progesterone in an ethanol solution is retained by four carbonaceous materials involves a reversible mechanism that conforms to a kinetic equation of unity partial order in both the progesterone concentration in solution, the coverage fraction (θ) of the adsorbing surface and (1−θ). Over the temperature range 10–40 °C, the specific rate constant varies from 5.29×10−4 to 44.85×10−4 s−1. The formation of the activated species involved in the adsorption process is an endothermal, exoentropic step. The rate of the adsorption–desorption process is primarily determined by diffusion of progesterone molecules in the pores of the sorbent.