Application of magnetic-biomass-derived activated carbon as an adsorbent for the treatment of recalcitrant wastewater

Two types of biomass adsorbents have been developed in this study using Palm Kernel Shell Activated Carbon (PKS-AC), iron oxide, and zeolite. Micrographs and the adsorbent’s chemical composition were identified using a scanning electron microscopy with a energy-dispersive X-ray (SEM-EDX), and a Brunauer–Emmett–Teller analysis was used to determine the specific surface area of the adsorbents. The newly developed adsorbents have been used for the adsorption of Palm Oil Mill Effluent (POME). The effects of adsorbent dosage, contact time, and initial solution pH were identified using Design of Experiment. The Iron Oxide Palm Kernel Shell Activated Carbon (Fe/PKS-AC) shows the highest color removal efficiency (93.2 percent) compared to Zeolite Iron Oxide Palm Kernel Shell Activated Carbon (Zeolite-Fe/PKS-AC) using 5 g/L of adsorbent dosage, an initial pH of 3 and a retention time of 40 min and 60 min, respectively. Besides, Zeolite-Fe/PKS-AC reported higher degradation efficiency (62.6%) than Fe/PKS-AC within an hour of contact time. The reusability study also shows that Zeolite-Fe/PKS-AC could retain its adsorbent capability over five cycles and had a minimal decrease of 5.6 %. It can be deduced that the newly developed biomass adsorbents from palm kernel shells can provide a cost-effective alternative for the treatment of POME and other recalcitrant wastewaters.