This chapter reports the possible use of ionic liquids (ILs) in solid-liquid separation processes by their immobilization in suitable solid supports. This method presents some beneits such as economical one-due to the fact that a smaller quantity of ILs is used and the loss of ILs in the aqueous phase is avoided and second the eiciency beneitbecause the advantages of the ILs are combined with the properties of the solid support, and this enhances the removal process of metal ions from aqueous solutions and could be successfully used in the removal processes of metal ions from aqueous solutions containing trace amounts. The type of solid supports used for the immobilization of diferent ILs, and the methods used for the immobilization were discussed. "lso the adsorption eiciency of these ionic liquid immobilized solid supports in the removal process of diferent metal ions (Cr, Hg, Pt, "u, Pd, Cs, Sr, Tl, etc.) from aqueous solutions were presented. The inorganic materials present a higher eiciency to be used as solid supports for the immobilization of the ILs. It was observed that the physical method of impregnation, especially ultrasonication, has a positive efect on the adsorption capacities of the materials obtained.