The effect of temperature and adsorbate concentration on biosorption on Pb and Cu using spent mushroom substrate Coprinus comatus
摘要
Riau Province is Indonesia’s largest palm oil plantation area, with an annual Crude Palm Oil (CPO) production of 9,059,611 tons. Each factory produces 22–30 tons of Empty Fruit Bunches (EFB) per hour, which can be processed into Spent Mushroom Substrate (SMS). Copper (Cu) and lead (Pb) are highly toxic heavy metals, and their removal from wastewater can be effectively achieved through biosorption—a simple, cost-effective, and environmentally friendly method. This study investigates the optimal temperature and initial concentration for biosorbing Pb(II) and Cu(II) by evaluating removal efficiency and biosorption capacity, as well as determining isotherm and thermodynamic parameters. The experimental variables included temperature (30 °C, 40 °C, 50 °C) and initial concentration (10, 20, 30, 40, 50 mg/L). BET analysis showed that the surface area of SMS is 1.467 m2/g. The highest biosorption efficiencies were observed at 50 °C and an initial concentration of 10 mg/L, with Pb(II) achieving 87.50% and Cu(II) 86.82%. The maximum biosorption capacities were 19.466 mg/g for Pb(II) and 19.092 mg/g for Cu(II). The Langmuir and Freundlich models best described the isotherms, with high R2 values for both metals. Thermodynamic analysis indicated that biosorption is spontaneous and endothermic, with increased disorder between the biosorbent surface and the adsorbate. These findings suggest that SMS is an effective biosorbent for Pb(II) and Cu(II) removal from wastewater under optimal conditions.