the amount of the adsorbed dye onto cotton fiber increases with time and, at some point in time,
reaches a constant value beyond which no more is adsorbed from solution. At this point, the amount of dye being adsorbed onto cotton fiber is in a state of dynamic equilibrium with the amount of the dye desorbing from the fiber. The time required to attain this state of equilibrium is termed the equilibrium time, and the amount of dye adsorbed at the equilibrium time reflects the maximum adsorption capacity of the cotton fiber under those operating conditions