Adsorption of polycyclic aromatic hydrocarbons on banana peel activated carbon

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are potential pollutants, released in aqueous systems through various sources such as industrial wastewaters, agricultural run-off, and deposition from the polluted air. The present study proposes an efficient and inexpensive approach to remove PAHs from aqueous system using activated carbon synthesized from waste banana peel. The Brunauer–Emmett–Teller N2 surface area of the developed banana peel-activated carbon (BPAC) is more than 900 m2/g. Effects of contact time, adsorbent dose, pH, and temperature on adsorption of PAHs have been examined. Results were fitted to Langmuir and Freundlich models, and characteristic parameters for both the adsorption isotherms were calculated. Data is better fitted to Freundlich model. The equilibrium time for the adsorption on BPAC is found to be 80 min. Equilibrium constants obtained from Langmuir adsorption isotherms have been used to calculate the thermodynamic parameters, such as (Formula presented.) , (Formula presented.) , and (Formula presented.). The result revealed that adsorption of PAHs onto BPAC is spontaneous and endothermic. Quantitative desorption of PAHs from BPAC has been achieved using sodium hydroxide and ethanol mixture, indicating the reuse of prepared activated carbon. The study thus provides cheap and easily acquirable adsorbent which effectively removes PAHs from aqueous system. © 2015 Balaban Desalination Publications. All rights reserved.