Another key feature for any water treatment technology is the use of sorbent materials by several adsorption-desorption cycles. For regeneration and reusability of nanostructured adsorbents, surface treatment with alkaline eluents (e.g., NaOH) allowed the sorbent regeneration by removing 99% of arsenic from graphene-oxide composites with metal oxides such as CuFe2O4, Gd2O3, Fe3O4, and CuO), Zn-Fe mixed metal oxides, Fe3O4/Halloysite nanocomposites, Fe/Cu-polyurethane nanoparticles, and Tioxides . Therefore, the phosphorene oxide reusability as a function of the oxidation degree was investigated by considering hydroxide (OH -) anions as eluents.