Optimization of Methylene Blue Ultrasound-Assisted Adsorption onto Magnetic Sugarcane Bagasse Activated Carbon Using Response Surface Methodology

This study focused on the optimization of methylene blue removal on a magnetic activated carbon from the carbon-rich agro-industrial residue, sugarcane bagasse, synthesized by microwave method. The adsorption process was assisted by ultrasound. The magnetic sugarcane bagasse activated carbon (MSB) was characterized by FTIR and SEM-EDX. Based on FTIR results, the functional groups found in magnetic sugarcane bagasse activated carbon are O-H, C=C, C-O, and Fe-O. The SEM results show that MSB is porous with a rough surface. In addition, EDX data found the presence of three main elements, namely C, O, and Fe. Response Surface Methodology (RSM) Box-Behnken Design was applied to analyze the effects of three parameters, including adsorbent dosage (50-100 mg/L), ultrasonic power (100-200 W), and contact time (30-60 min). The obtained optimum conditions of the adsorption process were the sonication power of 155.65 W, the adsorbent dosage of 89.77 mg/L, and the sonication time of 57,81 minutes. The results indicated that the parameters of adsorbent dosage, ultrasonic power, and contact time influenced the response (qe and methylene blue removal).