Adsorption of brilliant cresyl blue using NaOH-activated biochar derived from sewage sludge

¹ Laboratory of Materials, Nanotechnologies and Environment, Faculty of Sciences, Mohammed V University in Rabat, Morocco
² Laboratory of Advanced Materials and Process Engineering, Department of Chemistry, Faculty of Sciences, Ibn Tofaïl University, B.P. 133, Kenitra 14000, Morocco
³ Laboratory of Quality Control of Waters, National Office of Electricity and Drinking Water (ONEE), Rabat, Morocco
⁴ Laboratory of Spectroscopy, Molecular Modeling, Materials, Nanomaterials, Water and Environment, Environmental Materials Team, ENSAM, Mohammed V University in Rabat, Morocco

^* Corresponding author: majda-benali@um5r.ac.ma

Abstract

The treatment of sewage wastewater generates a substantial amount of sludge, which poses significant ecotoxicological and environmental challenges. Managing this sludge is critical, as traditional disposal methods carry risks: agricultural use can lead to environmental contamination, while landfill disposal raises concerns about solid waste management and the preservation of landfill sites. Our research focuses on converting this urban sludge into activated carbon. We employed various techniques to characterize NaOH-activated biochar, including infrared (IR) analysis. BET analysis revealed a specific surface area of 62.35 m²/g. We also assessed NaOH-activated biochar for its effectiveness in adsorbing brilliant cresyl bleu (BCB). The SSE error calculations indicated a first-order adsorption, while the isotherms suggested a better fit with the Sips model, indicating heterogeneous adsorption with an ns value of 0.95. Our study highlights the effectiveness of biochar in adsorbing dyes such as brilliant cresyl bleu BCB.