Role of Chemical Activating Agent on the Characteristics of Activated Carbon Derived from Fruit-Peel Waste for Aqueous Dye Removal

Abstract

Dye pollutants are commonly found in waste water, posing a health risk. Adsorption is a potential technique for dye removal, because of its long-term viability, bio-adsorption is favored. Bio-adsorbent derived from local sources provides a long-term production supply. However, there is a wide range of bio-adsorption, which leads to differences in bio-adsorbent kinetics and characteristics. Tanjung fruit (Mimusops Elengi) peels are used to make activated carbon with a large specific surface area and high porosity. This fruit is one of the readily accessible native fruits in East Kalimantan. The effects of three activators (H3PO4, NaCl, and KOH) were studied. Characterization and analysis is conducted by Scanning Electron Microscopy (SEM) for surface morphology analysis and BET method for porosity analysis.The results reveal that acid activation (H3PO4) was successful in producing highly porous activated carbon, which has greater adsorption performance than salt (NaCl) and alkaline activation (KOH). The use of salt (NaCl) as an activating agent resulted in a greater development of broad porosity during the activation thermal treatment that followed. The carbon was activated at 500°C had a BET surface area of 587.59 m2g-1 and a pore size of 28.27 ml g-1, respectively. For isothermal and kinetics, the Langmuir model and pseudo-first-order reaction are the best fit models. Our findings provide important information on the guided synthesis of large-surface-area, extremely porous activated carbons from local biomass waste, which has a potential for adsorptive dye removal.