Experimental investigation and DFT studies of fluorescein adsorption onto modified agave angustifolia fiber biosorbent

This study aims to assess the potential application of Agave angustifolia “Marginata” fibers as a readily available biosorbent in the sequestration process of fluorescein dye (FD) waste water. Three distinct samples were analyzed with the help of Fourier transform infrared (FTIR), scanning electron microscope (SEM), and energy dispersive spectroscopy (EDS) analysis, batch biosorption kinetics, batch biosorption isotherms, density functional theory (DFT) simulations, and desorption analysis. Three distinct Agave angustifolia samples-natural (NAA), chemically altered (CAA), and sonicated (SAA)-were used in the study. This high-performance study showed the potential application of the Agave angustifolia fibers with their ability to spontaneously undergo monolayer adsorption following pseudo-second-order reaction kinetics, with Langmuir isotherms. The study showed that the highest capacity reached 37.18 mg/g with CAA, 28.74 mg/g with SAA, and 11.30 mg/g with NAA. Desorption analysis successfully showed the regenerability of the fiber.