Production of Activated Biochar from Palm Kernel Shell for Methylene Blue Removal

In this study, Palm kernel shell (PKS) is utilized as a raw material to produce activated biochar as adsorbent for dye removal from wastewater, specifically methylene blue (MB) dye, by utilizing a simplified and cost-effective approach. Production of activated biochar was carried out using both a furnace and a domestic microwave oven without an inert atmosphere. Three samples of palm kernel shell (PKS) based activated biochar labeled as samples A, B and C were carbonized inside the furnace at 800°C for 1 h and then activated using the microwave-heating technique with varying heating times (0, 5, 10, and 15 min). The heating was conducted in the absence of an inert gas. Fourier Transform Infrared Spectroscopy (FTIR) highlighted a significant Si-O stretching vibration between 1040.5 to 692.7 cm−1, indicating the presence of key components (Silica and Alumina) in all PKS-based activated biochar samples. For wastewater treatment, activated biochar samples were tested against a 20 mg/L Methylene Blue (MB) solution, and the MB percentage removal was calculated for each run using a standard curve. Central Composite Design (CCD) experiments were conducted for optimization, with activated biochar Sample C exhibiting the highest adsorption capacity at 88.14% MB removal under specific conditions. ANOVA analysis confirmed the significance of the quadratic model, with a p-value of 0.0222 and R2 = 0.9438. In conclusion, the results demonstrated the efficiency of PKS-based activated biochar as an adsorbent for MB removal in comparison to other commercial adsorbents.