Arenst Andreas

Delignification, Carbonization Temperature and Carbonization Time Effects on the Hydrothermal Conversion of Salacca Peel

Hydrochar from the hydrothermal treatment of biomass is considered as a potential precursor for activated carbons (AC) which has been widely utilized not only for adsorbents but also for energy storage application. The advantages of hydrochar from hydrothermal treatment include its high Oxygenated Functional Group (OFG) and high porosity. The authors have been working on the biomass conversion for energy storage application. In our study, salacca peel was used as a biomass source. In previous research for the preparation of AC, conventional carbonization and activation methods were used, resulting in a high surface area of AC. In the current research, the authors investigated the biomass conversion in hydrothermal conditions. Water at a subcritical condition (with temperatures of 200, 225 and 250 °C and at a pressure of 50 MPa) and carbonization time of 4, 5 or 6 hours, with or without delignification, were critical in the research to investigate the conversion of salacca peel into hydrochar. The produced hydrochar from 225 °C, 5 h was chemically activated and compared to commercially-AC. The hydrochar and AC were then used as electrodes for the supercapacitor, and capacitance was measured by cyclic voltammetry (CV). The results showed that the capacitance of hydrochar was higher than that of AC while ACs from salacca peel exhibited much higher levels of capacitance compared to commercially-AC.

A study on the adsorption equilibrium and kinetics of methylene blue onto orange peel wastes as biosorbents

The main aim of this work was to explore the potential application of orange peel waste as biosorbents for removing methylene blue (MB) in aqueous solution. We will investigate the effects of different adsorption parameters such as the initial concentration of MB, adsorption time; adsorbent dosage, adsorption temperature and initial pH on MB adsorption. It was found that the adsorption capacity was enhanced as the dye initial concentration, contact time and solution temperature. The adsorption equilibrium was studied by fitting the experimental data by three adsorption isotherms such as Langmuir, Temkin and Freundlich models. It was found that the equilibrium data could be best represented by the Freundlich model. Meanwhile, the best adsorption kinetic model was the pseudo-second-order kinetic model. From the experimental results, it indicated that orange peel waste might be used as effective and efficient biosorbent for the treatment of dye solution.