Carbon-derived Black Soldier Fly (BSF) Larvae for Adsorption of Methylene Blue Dye: Characterization, Kinetic and Thermodynamic Studies

Abstract

The most effective substance for effectively adsorbing organic dyes is activated carbon (AC). We looked at the possibility of using Black Soldier Fly (BSF) larvae (Hermetia illucens Genome, MG) as a source for AC in this study. The two unique materials known as MG(300) and MG(500) were produced as a result of the larvae being heated for two hours at 300 and 500°C, respectively. These MG materials were further activated (MGO) using hydrogen peroxide (H2O2), and subsequently utilized for the adsorption of methylene blue (MB) dye. The objectives of this research include: (1) Investigation of the cabonization temperature and activation effects of the MG and MGO towards adsorption capacity; (2) Study of the physico-chemical properties of the adsorbents; (3) Exploration of the adsorptivity of MG and MGO in different parameters, including initial dye concentration, contact time, and temperature; (4) Examination of the kinetic and thermodynamic findings for the MG and MGO towards adsorption capacity. To analyze the obtained carbon, various analytical methods, including FTIR, WDXRF, SEM, and BET, were used. The equilibrium and kinetics of MB dye's adsorption behaviour on the AC were carefully investigated. It's interesting to note that within the first 10 minutes of contact time, all adsorbents demonstrated quick MB adsorption. The dye removal percentage (%) and adsorption capacities (mg×g-1) were measured at 65.7% and 6.33 mg×g⁻¹ for MG(300), 76.5% and 11.07 mg×g⁻¹ for MG(500), 91.1% and 16.41 mg×g⁻¹ for MGO(300), and 96.1% and 17.13 mg×g⁻¹ for MGO(500). Furthermore, the kinetics of dye adsorption using the pseudo-first-order (PFO) and pseudo-second-order (PSO) models were conducted, whereby PSO is the best fit with R2 in the range of 0.949 to 0.999.