Fabrication of Efficient Calix[4]arene-Adorned Magnetic Nanoparticles for the Removal of Cr(VI)/As(V) anions from Aqueous Solutions

Abstract

A new 1,3-distal diphenyl(4-piperidin)methanol-appended calix[4]arene derivative 3 has been successfully synthesized and characterized using FTIR, NMR and elemental analysis techniques. Synthesized 1,3-distal diphenyl(4-piperidin)methanol-appended calix[4]arene derivative 3 has been then grafted onto [3-(2,3-epoxypropoxy)-propyl]-trimethoxysilane-modified Fe3O4 magnetic nanoparticles to produce 1,3-distal diphenyl(4-piperidin)methanol-substituted calix[4]arene derivative-grafted EPPTMS-MN (4). The structure and surface morphology of 1,3-distal diphenyl(4-piperidin)methanol-substituted calix[4]arene derivative-grafted EPPTMS-MN have been determined by a combination of FTIR, transmission electron microscopy (TEM) and thermogravimetric analysis (TGA) techniques. Moreover, anion binding capabilities of 1,3-distal diphenyl(4-piperidin)methanol-substituted calix[4]arene derivative-grafted EPPTMS-MN toward HCr2O7 -, and H2AsO4 - ions have been evaluated. The results indicate that 1,3-distal diphenyl(4-piperidin)methanol-substituted calix[4]arene derivative-grafted EPPTMS-MN exhibited 80% sorption efficacy toward Cr(VI), whereas ∼8% sorption efficacy for As(V) was obtained.