Mechanistic Insight and Optimal Remediation Strategy of Methylene Blue Using Waste Banana Peel in a Circular Economy Approach

Compared to other approaches, using biosorbents for dye removal has several benefits. Biosorbents are inexpensive, very effective and environmentally beneficial. Banana peel (BP) was used as the feedstock to create a biosorbent for methylene blue (MB) adsorption in aqueous medium. Several analytical methods such as Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) analysis and field emission scanning electron microscope (FE-SEM) analysis were used to characterize the produced composite. FTIR spectroscopy reveals the presence of functional groups. The optimum percentage of removal of 97.41% for MB, was achieved at pH 7, 10 mg/L of dye solution and 400 mg/L of adsorbent dosage, agitated for 24 h at 120 rpm. Each experimental runs’ parameters were determined and the adsorption level was optimized using the Box-Behnken design (BBD) of the response surface methodology (RSM). For MB, the optimized elimination efficiency was found to be 96.524%. The experimental data that were gathered agreed well with what the model anticipated, proving the value of the RSM methodology for modelling and optimization. The availability of cheap biological raw materials for the mass production process makes it economically feasible.