Microwave-assisted production of biochar from oil palm mesocarp fiber and its dye removal properties

Malaysia is one of the largest producers of palm oil in the world, which inevitably would also result in huge production of oil palm biomass. Without proper management, this biomass could pose serious environmental problems. Oil palm mesocarp fiber (OPMF) is one type of oil palm biomass which can be processed further for useful application such as dye removal from water. In the present study, OPMF was thermally treated using microwave-assisted pyrolysis. The sample was characterized (proximate, ultimate, lignin content, BET, FTIR, and SEM) and investigated using thermogravimetric analyzer. The activation energy and pre-exponential factor achieved from the Kissinger, Kissinger-Akahira-Sunose (KAS) and Ozawa-Flynn-Wall (OFW) methods were 159.74, 161.90, 163.29 kJ mol−1, and 1.02 × 10−10, 1.90 × 10−13, 3.79 × 10−17 min−1, respectively. The dye removal performance was evaluated using methylene blue (MB) with parameters of initial concentration of MB, contact time, biochar dosage, temperature and pH. The kinetics of MB removal by OPMF was best described using the pseudo-second order kinetic model, followed by Elovich, pseudo-first order and Weber-Morris. As a conclusion, OPMF generated from oil palm processing has the potential to be used as alternative raw materials to produce biochar for dye removal application