Utilization of Fruits Peel as a Sorbent for Removal of Methylene Blue

The potential of using fruits skin as a low cost sorbent in the removal of methylene blue from aqueous solution was studied. The sorption behaviour of various fruits skin for methylene blue was carried out as a function of pH, contact time, concentration of methylene blue and sorption isotherms. The sorption process was rapid with high percentage of uptake taking place within the first 1 h, regardless of its initial concentration. Different kinetic models were selected to interpret the experimental data. The sorption process conformed to Langmuir isotherm and maximum sorption capacities for methylene blue were 56.50, 34.97, 50.51, 48.54, 48.31 and 78.74 mg/g for mangosteen's peel, pulasan's peel, pineapple's peel, durian husk, orange's peel and pamelo's peel, respectively. Mathematical models were employed to analyze and explain experimental data obtained. It was found that application of pseudo-second order kinetics provides better correlation of the experimental data than the pseudo-first order model for the different systems studied.