Removal of methylene blue from aqueous solutions by silica gel supported calix[4]arene cage: Investigation of adsorption properties

Abstract

The silica gel supported dinitro calix[4]arene cage (DNCC) was successfully prepared by immobilization of 3-glycidoxypropyl-bonded stationary phase (GBS) on p-tert-butylcalix[4]arene derivative having p-nitro benzyloxy moieties. The structural and composition analysis of the DNCC was performed by FT-IR, XRD, EDX, SEM, BET, and TGA techniques. After that, the proposed polymeric material as an adsorbent was used for the adsorption of methylene blue (MB) from aqueous solutions. Initial adsorption experiments demonstrated that DNCC showed outstanding performance for the removal of MB from aqueous solutions. Furthermore, many adsorption experiments were performed to evaluate the effects of some adsorption criteria on the MB adsorption. The MB adsorption capacity of DNCC was obtained approximately 212.770 mg g(-1). Besides, thermodynamic parameters were evaluated and it was concluded that the MB adsorption came true in exothermically and spontaneously. Adsorption phenomena of MB on DNCC were clarified by the investigation of isotherm and kinetic criteria. Finally, the applicability of proposed adsorbent for MB adsorption was investigated in real samples such as tap water and textile wastewater.