The adsorbent is continuously washed by a flow of solvent (moving phase) passing through columu. Initially, the components of the mixture adsorb onto the solid phase at the top of the cilumn. The continuous flow of solvent through the column elutes, or washes the solutes off adsorbent and sweeps them down the column. The solutes are called eluates or elutants, and the solvents are called eluents.As the solutes ,pass down the column to fresh adsorbent, new equilibria are established among the adsorbent, the solutes , and the solvent. The constant equilibration means the different compounds will move down at differing rates depnding on their relative affinity for the adsorbent on the one hand,