Adsorption of Methylene Blue Dye from Aqueous Solution by using Activated Carbon Orange Peels

Methylene blue (MB) dye present in industrial wastewater is hazardous to the environment and health due to it toxicity and does not degrade easily. Available treatments are expensive and not environmentally friendly, while activated carbon (AC) depends heavily on non-renewable resources. In this study, the adsorption of MB dyes from aqueous solution was performed by using orange peels waste activated carbon (OPWAC) produced through a carbonization and chemical activation using sulfuric acid (H2SO4). This study aims to reveal how AC derived from orange peels waste is capable of removing MB dyes effectively. To comprehend the adsorption studies, the effect of concentration varied from 100-500 mg/L were investigated and UV-Vis spectroscopy was employed to quantify the adsorption efficiency by evaluating the decrease in MB’s characteristic absorbance near 664 nm. It was found that OPWAC absorbs significant amounts of dye, reaching a maximum capacity of 176.908 mg/g and removing 89.07% of the dye at 500 mg/L and the efficiency rises as the initial dye level in the solution increases, in accordance with adsorption isotherm models.The FTIR analysis confirmed that OPWAC interacted with MB dye and showed various changes in its functional groups during the adsorption process. OPWAC is found as suitable adsorbent that can be used for treating wastewater and recycling agricultural waste, while also supporting circular economy practices.