Sustainable Porous Carbon from Tapioca Peel waste for Dye Adsorption

The present investigation examines the adsorptive capacity of the charcoal obtained from the peel of Manihot esculenta tuber, an inexpensive and abundantly available waste activated using microwaves. This tuber is commonly called tapioca or cassava . The steadily growing interest in the field of adsorption research is the preparation of activated carbons. The activation includes chemical and thermal processes that require long processing time, involve high energy and chemical consumption, which may negatively affects the quality of the activated carbons prepared. In this study, charcoal made from tapioca peel was activated with microwave irradiation and comparative studies were carried out for thermally activated carbon and microwave activated carbon. Batch mode adsorption studies were carried out to study the effect of contact time, adsorbent dosage, concentration, temperature and pH. Adsorption kinetics were analysed using Pseudo second order model. MWTPC showed greater adsorptive capacity of 238mg g ^-1 and highest rate constant of .012 g mg ^-1 min ^-1 which is ten times greater than that for TATPC. Results of the Freundlich and Langmuir adsorption isotherms were determined and discussed technically. Isotherms also showed superior performance for Microwave activated carbons. MWTPC showed enhanced adsorption at smaller dosage of 2g L ^-1 . Thermodynamic parameters such as ∆H, ∆G, and ∆S were calculated and the adsorption was found to be more feasible. The adsorbents were characterized using IR and SEM. Studies showed the distinct nature of adsorbents, enhanced adsorptive capacity and improved feasibility of the adsorbent as a result of microwave activation