if you want to degrade a dyestuff, you measure the degradation kinetic. if you want to measure an adsorption process, you must be sure, that you dont have a degradation, that can interact with your adsorption.
The important point in every kinetic analysis, is the factor that you get enough data point from the start of the kinetic. If the equilibrium is almost reached, you can't do a kinetic analysis of the data.