| Summary: | This research attempts to remove extremely toxic methylene blue dye (MB) from water through adsorption process using rice husk based activated carbon (RHAC). This work utilized a simple RHAC preparation method from rice husk via microwace irridiation activation process involving carbon dioxide, CO2 gasification. Response surface methodology (RSM) was implemented to obtained an optimum preparation conditions of RHAC. The optimum preparation conditions were at microwave radiation power of 440 W for 4.28 minutes of activation time, which gave 83.93 % of MB removal and RHAC yield of 32.55 %. Adsorption performance of RHAC for MB removal was evaluated by batch adsorption process where the effects of 3 different variables (initial MB concentration, contact time and solution temperature) were studied. As MB initial concentration increased, the MB uptakes increased whilst MB percentage removal decreased. MB uptakes and percentage removal were found to increase with contact time. Highest MB removal was obtained at highest solution temperature of 60 °C with 88.82 %, thus signified endothermic nature. Characterization results showed an improvement in terms of surface functionality (Fourier-transform infrared spectroscopy, FTIR), high fixed carbon content of 70.34 %, and excellent physical properties where optimized RHAC have pore volume of 0.35 cm3/g, surface area of 668.30 m2/g and average pore diameter of 4.42 nm. Last but not least, the adsorption equilibrium analysis of RHAC/MB adsorption system was found to well matched the Freundlich isotherm. Meanwhile, for adsorption kinetic analysis, pseudo-first-order kinetic model was best suited the MB-RHAC system. © Malaysian Journal of Microscopy (2023). All rights reserved.
|
|---|