Study of the Clinoptilolite-Rich Tuff-Based Composites for Some Aqueous Anionic Species Recovery

Abstract

Batch and column sorption experiments have been performed to study a significantly enhanced removal of toxic oxyanions, i.e. chromate and arsenate from aqueous effluents on inland clinoptilolite modified by the octadecylammonium acetate [ODA]. The arrangements (orientation and length) of the surface-attached organic chains and thus the initial concentration of ODA — modifier by composite preparation have been the important factor for the difference in the adsorption states of the guest species [oxyanions]. Novel nano-structure inorganic — organic composites prepared have been investigated using SEM, thermogravimetry, NMR, IR, HR TEM, UV-VIS DRS and powder XRD spectral analytical methods. Finally, adsorption isotherms for system studied have been expressed. Some approach for regeneration of exhausted surfactant-immobilized clinoptilolite with inorganic salt solutions under dynamic regime has been proposed, respectively.