Layered doubled hydroxides nanocomposites for enhanced water and wastewater treatment: from ancient tradition to recent advances

Over different periods of human history till date, absorption has been one of the most popular techniques for the purification of water. This owes to the adsorption process's inherent simplicity as well as readily available adsorbent materials which included natural materials such as clay bentonite and charcoal. Recent technological advances and the synthesis of functional materials have provided the opportunity for the emergence of different types and classes of highly adsorptive materials that include layered double hydroxides (LDH) nanocomposites. LDHs are traditionally characterized by high surface area and excellent performances for effective decontamination of water and wastewater treatment via adsorption processes. In light of historical perspectives of applications adsorption for water treatment, this paper reports on LDH nanocomposites synthesized their characterization and adsorptive performance evaluations. Their improved adsorptive characteristics in terms of improved sorption surface area, surface oxygen-functional groups, higher pore sizes and higher adsorptive capacities showcase the potential of these nanocomposites for utilization as adsorbents for the treatment of water and wastewater laden with organic and inorganic pollutants. Compared with many other reported similar adsorptive materials, these emerging LDH nanocomposite adsorbents demonstrated superlative adsorption capacities for a wide range of target contaminants while exhibiting higher regenerability capabilities. The prospect of using these novel nanomaterials synthesized as a result of modern advances in materials science led to a substantial opportunity for the treatment of wastewater, including industrial which significantly, advanced ancient civilization practices.