Removal of Methyl Orange from Aqueous Solution Using Orange Peel as a Low Cost Adsorbent

Abstract

The objective of this research was to evaluate the feasibility of using orange peels as a low-cost adsorbent to remove methyl orange (MO) from water solutions. The orange peel adsorbent underwent characterization through Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) Spectroscopy to determine its properties before and after adsorption. A series of batch adsorption experiments were carried out to investigate the effects of various parameters such as contact time, adsorbent dosage, particle size, and initial dye concentration on the adsorption process. In each case, varying the value of the parameter of interest while keeping all other parameters constant. Results revealed that the highest removal of the dye from the adsorbent was achieved at a contact time of 90 min, the adsorbent dosage of 0.5 g, a particle size of less than 63 µm, and an initial concentration of 300 mg/L. Furthermore, the adsorption rate increased with increasing contact time, adsorbent dosage, and initial concentration, while it decreased with increasing particle size of the adsorbent. Concentrations of methyl orange were analyzed using a UV-Vis spectrophotometer. The experimental equilibrium data was analyzed using Langmuir and Freundlich isotherm models. The Langmuir isotherm provided the best fit for the experimental data with a correlation coefficient value of 0.9964 and a maximum adsorption capacity of 17.69 mg/g.