Converting Blended Chicken Bone And Rice Food Wastes Into Activated Carbon Via Microwave Process: Box-Benken Optimization For Methyl Violet Dye Removal

Herein, chicken bone (CB) and rice waste (RW) food were converted to activated carbon (CBRWAC) via microwave assisted H₃PO₄ activation. The applicability of CBRWAC as an efficient adsorbent was evaluated for its removal  efficacy of a cationic dye, namely methyl violet (MV), from an aqueous environment. The physicochemical properties of CBRWAC were characterized by several analytical methods such as BET, XRD, pH_pzc, FTIR, and SEM–EDX. The Box-Behnken design (BBD) was adopted to optimize the effect of three adsorption processing variables namely CBRWAC dose (0.02–0.1 g/100 mL), solution pH (4–10), and contact time (10–200 min) for the removal of MV dye. The results of the equilibrium and kinetic investigation indicates that the adsorption of MV dye by CBRWAC was well described by the Langmuir and Freundlich isotherm models, as well as the pseudo-second-order model for adsorption kinetics. The CBRWAC has a maximum adsorption capacity (q_max) of 126.3 mg/g. The proposed adsorption mechanism of MV by CBRWAC was assigned to the electrostatic interactions, π -π stacking, pore filling, and H-bonding. The current investigation highlights the possibility of food waste conversion into activated carbon with potentially wider utility for the removal of a wider range of toxic cationic dyes from contaminated water.