Cu-ZIF@ red soil nanocomposite sufficient sorbent for dye removal

Abstract

In this study, Cu-ZIF and Cu-ZIF@ Red soil Nano composite were synthesized in room temperature. Red soil, Cu-ZIF and Cu-ZIF@ Red soil Nano composite were fully characterized by different techniques such as Fourier transform spectroscopy infrared (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), elemental mapping, BET and thermal gravimetric analysis (TG). The results of FESEM indicated Cu-ZIF@ Red soil had meso porous nature with uniform spherical shape of 30 nm. The XRD result showed the main phase of red soil was hematite (Fe2O3) and hexagonal crystal system (primitive R3) and α-SiO2 and the crystal structure of red soil and Cu-ZIF remain unchanged after formation of composite. Adsorption of malachite green (MG) by prepared samples were studied. The highest percent of MG adsorption was occurred at contact time of 60 min, pH 10, and adsorbent dose of 0.1 g. Kinetic studies indicated that the adsorption of MG follows by pseudo second-order model. Thermodynamic results revealed that the adsorption of MG is endothermic, spontaneously process and feasible in the range of 298–338 K. The adsorption isotherm experimental data was fitted better by Langmuir model than Freundlich model. The maximum adsorption capacity of MG for Red soil, Cu-ZIF and Cu-ZIF@ Red soil Nano composite was observed 132, 366.6 and 382 mg g−1, respectively at pH 10. Cu-ZIF@ Red soil Nano composite acts as sufficient reusable sorbent for MG dye.