Adsorption Study of Reactive Violet 8 and Congo Red Dyes onto Aloe Vera Micropowder Impregnated with Cu Atoms as a Natural Modified Sorbent and Related Kinetics and Thermodynamics

Abstract

In this research, at first ordinary Aloe Vera micropowder (OAMP) and its impregnated form (IAMP) as the natural sorbents were prepared and then characterized by several techniques such as Fourier transform spectrophotometry (FT-IR), Scanning electron microscopy (SEM), Elemental analysis (EA), Brunauer–Emmett–Teller and Barrett-Joyner-Halenda (BET/BJH) essay and X-ray powder diffraction (XRD). The removal efficiencies of the prepared adsorbents were assessed upon their capacities for removing Reactive violet 8 (RV8) and Congo red (CR) dyes as the organic pollutants. Our preliminary adsorption experiments showed that the OAMB ability for removing RV8 and CR is very less than the IAMP form, so we focused on the IAMP removal ability and we used it as a fairy powerful adsorbent in this study. The effect of several parameters such as initial adsorbate concentration (C0), adsorbent dosage, contact time, temperature and solution pH on the adsorption capacity of IAMP adsorbent were investigated and then several isotherm models were examined to fit the experimental results. Consequently, we concluded that the Langmuir and Freundlich models fit reasonably the experimental results. In addition, thermodynamic and kinetic studies of the adsorption process were also done and the corresponding thermodynamic and kinetic parameters were concluded and reported.