Glycogen-assisted biosynthesis of MnO2 for adsorptive elimination of methylene blue from water

A novel biosynthesis of manganese dioxide (MnO 2 ) NPs was achieved by oxidizing glycogen with KMnO 4 in an alkaline medium. X-ray powder diffraction, Fourier-transform infrared spectroscopy, N 2 sorption, and transmission electron microscope (TEM) techniques were utilized to assess the physicochemical characteristics of the prepared MnO 2 . The impacts of different adsorption parameters, including contact time, pH, concentration, temperature, and adsorbent dose, on methylene blue (MB) elimination utilizing the prepared MnO 2 NPs, were investigated. It was found that the Langmuir model well describes how the dye molecules arrange themselves on the MnO 2 surface compared to other models. This proposes a single layer of dye forms, with each molecule attaching to a specific site on the MnO 2 . Additionally, the results were well-matched with a pseudo-2nd-order model, demonstrating that chemical reactions had a significant role in the adsorption experiment. Under specific conditions (RT, natural pH of the dye solution, and 30 -minute contact time), the MnO 2 could hold up to 40.85 mg of dye per gram of MnO 2 (mg/g). Further analysis reflected that the adsorption procedure was spontaneous, which means it happened favorably without needing extra energy input. This suggests that biosynthesized MnO 2 has great potential as an eco-friendly material for cleaning up MB dye contamination in water.