Adsorption potential of Ionic Liquid-Modified ZnO nanoparticles for highly efficient removal of azo dye: Detailed isotherms and kinetics

Abstract In this study, bare and ionic liquid-modified nanoparticles have been synthesized using microwave irradiation method. The fabricated nanoparticles were characterized by different techniques viz. XRD, FT-IR, FESEM, and UV-Visible spectroscopy and were explored as adsorbent for effective removal of (Brilliant Blue R-250) azo dye from aqueous solutions. Various factors affecting the adsorption efficiency of synthesized nanoparticles (bare/ionic liquid-modified) such as concentration of dye, pH of reaction media, dose of nanoparticles, and reaction time, were thoroughly investigated with varying experimental conditions; on magnetic stirrer and in sonicator. The results exhibited a high adsorption efficiency of ionic liquid-modified nanoparticles for removal of dye as compared to the bare one. Also, an enhanced adsorption was observed via sonication than by magnetic stirring. Different isotherms such as Langmuir, Frendluich, and Tempkin were elaborated. Also, an evaluation of adsorption kinetics showed a linear pseudo-second-order equation for adsorption process.