Facilitated Diffusional Transport:

While a simple diffusion procedure is coupled along with chemical reactions, the net permeation rate might be greatly affected. Such a diffusional permeation is known as facilitated diffusional transport. Facilitated diffusion occurs in liquid membrane systems. This mechanism needs a carrier substance (X) within the membrane that shuttles back and forth among the two sides of the membrane carrying the permeant molecule (A). The schematic of facilitated diffusion that occurs in liquid membranes is given in Figure.

Figure:  A schematic representation of facilitated diffusion in liquid membranes