PENYERAPAN TIMBAL(II) dan KROMIUM(VI) DARI LARUTAN MENGGUNAKAN LIMBAH KULIT SINGKONG (Manihot Esculenta Crantz) SEBAGAI BIOSORBEN

Biosorption is a method of absorbing contaminants using a biosorbent to adsorb contaminants through chemical or physical interactions. The biosorbent possesses a chemical structure that can interact with the pollutant molecules. This study employed cassava peel as a biosorbent for the adsorption of Pb(II) and Cr(VI) metals in wastewater. The optimal adsorption parameters were determined by varying the pH, initial concentration, and contact time. The results indicated that the optimum adsorption of Pb(II) occurred at pH 5, initial concentration of 1000 mg/L, and contact time of 50 minutes. On the other hand, the optimal adsorption of Cr(VI) was achieved at pH 2, initial concentration of 1200 mg/L, and contact time of 70 minutes. The adsorption isotherms of both metals tended to follow the Langmuir model, while the adsorption kinetics followed the pseudo-second-order model. Thermodynamic parameters indicated that the adsorption process was spontaneous ΔG° negative, endothermic ΔH° positive, and exhibited surface dispersion on the biosorbent ΔS° positive. Characterization using FTIR, XRF, SEM, and TGA provided evidence of both physical and chemical adsorption.The adsorption capacity of cassava peel was also tested on samples collected approximately 30 meters from the bay shoreline, resulting in a removal percentage of 94.67% for Pb(II) and 82.28% for Cr(VI) under optimal pH and contact time conditions