Comparative study on biosorption of arsenite ions onto raw and chemically activated orange peel powder in batch reactor

Abstract

In present work, comparative study of sorption potential of raw and chemically activated orange peel powder has been explored for the removal of arsenite ions (As III) from wastewater. Several operating parameters such as contact time, adsorbent dose, adsorbate ion concentration, solution pH as well as temperature were studied in batch reactor. Surface as well as physicochemical analysis of orange peel was done by using FTIR (Fourier Transform Infrared Spectroscopy), SEM (Scanning Electron Microscopy), proximate and ultimate analysis. Maximum removal of As (III) 86.3% and 87% was obtained at initial metal ion concentration 20 mg/l and 25 mg/L, optimum pH 2 and 2.8, temperature 30°C and 25°C, contact time 120 and 150 minutes as well as the adsorbent dose 4g for raw and chemically activated orange peel respectively. Modeling of experimental data showed that Freundlich model (R² = 97.45) had a better fit over Langmuir isotherm (R² = 96.33) for raw orange peel and the Freundlich model (R² =99.8%) in comparison to Langmuir model (R² =94.5%) shows better fit. The present comparative study depicts that the chemically activated orange peel powder are more effective than raw orange peel powder. Thus, orange peel is found to be promising simple material for removal of arsenite ions (As III) ions.