The current work deals with modification of the surface of a silica–polyamine with amine-based ionic liquid (IL) and its application for removal of Cu²⁺ from an aqueous media. The absorbent is simply prepared from commercially available reagents. The material is characterized by FT-IR spectroscopy, thermogravimetric analysis (TGA), N₂ adsorption–desorption, and transmission electronic microscopy (TEM). Effects of several parameters on absorption efficiency, as well as activity of the absorbent to other metals, are also investigated. Moreover, the reusability of the absorbent is studied at the optimized condition.