Efficient attenuation of 17a-ethynylestradiol (EE2) and tetracycline using novel hybrid materials: batch and column reactor studies

Abstract

Clay minerals are composed of ne particles of hydrous aluminosilicates, and develop plasticity when mixed with water. A common characteristic of clay minerals is their layer structure, although they have diverse chemical, mineralogical, and physical characteristics. Clays possess a permanent net negative charge because of isomorphous substitution, which is responsible for the presence of exchangeable cations in the interspace region.1–3 Therefore, the electrical charge possessed by clay minerals and their microscale porosity makes them suitable as natural sorbing materials for several pollutants in the treatment of contaminated water. Although clay minerals are used widely to decontaminate inorganic pollutants from wastewater, pristine clay minerals possesses low sorption capacity for several hydrophobic and low- or nonpolar organic pollutants owing to the hydrophilic nature of these materials.4 Moreover, most clays show low settling capacity, limiting their wider practical application in wastewater treatment.5 The exchange of clay cations with organic cations produces useful hybrid materials for the attenuation of several non-polar organic contaminants (NOC) from aqueous solutions.6–10 Likewise, hybrid materials obtained by pillaring with poly(hydroxo-metal) cations and simultaneous intercalation of suitable organic cations are particularly suitable for wastewater treatment, because these materials show good affinity for organic impurities, and possess satisfactory settling capacity, allowing easy separation of solid and aqueous components.3