Calcined Black Soldier Fly Shells as a Sustainable Bio-Derived Coagulant for Efficient Removal of Cd, Cu, Pb, and Fe from Aqueous Systems Wahyu Setiawan (a), Siska Nuri Fadilah (a), Subriyer Nasir (b), Muhammad Said (b), Diah Kartika Sari (c), Fakhili Gulo (a,c*)
a) Department of Environmental Science, Postgraduate Program, Universitas Sriwijaya, Palembang 30139, South Sumatera, Indonesia
*fgulo[at]unsri.ac.id
b) Department of Chemical Engineering, Faculty of Engineering, Universitas Sriwijaya, Palembang, 30139, South Sumatera, Indonesia
c) Department of Chemistry Education, Universitas Sriwijaya, Inderalaya, Ogan Ilir 30862, Indonesia
Abstract
Heavy metal pollution in water is a significant environmental challenge and requires efficient, sustainable treatment technologies. Black Soldier Fly (BSF) is known to have a high carbonate mineral content, making it a potential bio-derived coagulant. This study evaluated the performance of calcined Black Soldier Fly shells (CBSFS) as a biomass-based biocoagulant for the removal of Cd, Cu, Pb, and Fe from solution. The experiment was conducted in batches with varying contact times (5-120 minutes) and initial concentrations (10 until 100 mg/L) at 28 celcius, natural pH, and stirring at 160 rpm. Metal concentrations were analysed using Atomic Absorption Spectroscopy (AAS). The results showed that CBSFS performance increased significantly over time, with efficiencies reaching 99.46% (Pb), 99.04% (Cd), 98.43% (Cu), and 96.90% (Fe) within 30 minutes and remaining high (>96%) for up to 120 minutes. At various concentrations, the removal efficiency ranged from 92.31 to 99.02%, indicating stable performance against changes in metal load. This removal pattern indicated the dominance of the coagulation-precipitation mechanism involving floc formation and separation through sedimentation. Overall, CBSFS demonstrated effective, stable performance and high potential as a biocoagulant for low-cost, efficient, and environmentally friendly heavy metal-contaminated water treatment applications that support a circular economy.
Keywords: Biocoagulant, CaCO3, Hermetia illucens, Heavy metals removal, Water treatment
