Adsorptive removal of anionic dye from aqueous solutions using powdered and calcined vegetables wastes as low-cost adsorbent

Abstract

In this study, we describe a behaviour comparison between powdered and calcined adsorbents prepared from vegetables waste of Persea species to remove Eriochrome Black T as anionic dye from aqueous solutions. Potential capabilities of these two adsorbents have been evaluated by studying some experimental parameters such as solution pH, adsorbent dosage, initial dye concentration, contact time and temperature. Kinetic study has been achieved by the application of pseudo-first and second orders and Elovich model. Results found agreed well with the pseudo-second order model. The experimental data were analysed using Langmuir, Freundlich and Tempkin isotherms models. The equilibrium data fitted well with the Freundlich isotherm and the adsorption capacities were calculated to be 120.50 mg/g and of 96.15 mg/g for calcined and powdered adsorbents, respectively. Thermodynamic study was also undertaken and provided important results indicating a spontaneous reaction and feasibility on the two adsorbents. The two adsorbents have been characterized via spectroscopic data such infrared spectrum, X-ray and by emission scanning electron microscopy.

Keywords

• persea species
• powdered adsorbent
• calcined adsorbent
• anionic dye
• removal