New approaches on the removal of pharmaceuticals from wastewaters with adsorbent materials

Abstract

This review article summarizes the alternative use of adsorbent materials for treatment of pharmaceutical wastewaters. Pharmaceutical wastewaters are very hazardous and toxic not only for the human but also for environmental life. The existence of various drug pollutants in such effluents surcharges the aqueous media. Therefore, apart from the proposed conventional (until now) methods applied (biodegradation, photocatalysis, ozonation, Fenton process, etc.), the applicability of adsorption as simple and low-cost technique is recently applied. Some of the most important materials discussed in this work are clays, polymers (chitosan), zeolites, various types of (activated) carbons, composite materials (graphene-based), agricultural wastes or soils. The key-factor about the selection of the most suitable adsorbent material has resulted after adsorption experiments varying some major parameters (pH, contact time, initial pharmaceutical compound concentration, ionic strength, etc.). However, the most crucial factor is the adsorption capacity. So, some isotherm models are also commented here (Langmuir, Freundlich, Sips), which predict the maximum theoretical adsorption capacity (Qm) of each material used.