Sustainable nanofibrous cellulose-based hydrogel beads derived from cigarette filter waste, functionalized with hyaluronic acid and encapsulated in chitosan/polyethylenimine for enhanced nickel(II) adsorption from aqueous media.

The inadequate disposal of cigarette butts markedly influences urban ecosystems, resulting in pollution and resource depletion. This research focused on reclaiming discarded cigarette filters for cellulose extraction, leading to the formulation of a cellulose-based adsorbent enhanced with hyaluronic acid. The adsorbent was then encapsulated using chitosan and polyethylenimine and underwent a crosslinking procedure with epichlorohydrin. Because of these comprehensive techniques, the researchers effectively created hydrogel beads made from cigarette filter nanofibers, designated as CFNF hydrogel beads. Characterization utilized XRD, XPS, FT-IR, SEM, EDX, and nitrogen adsorption-desorption isotherms for porosity analysis. The adsorbent effectively captures divalent nickel (II) ions, realizing an impressive adsorption capability of 281.4 mg/g owing to the abundance of functional groups like amine, hydroxyl, and carboxylic groups. Various factors with dosage, pH, temperature, and original concentration were analyzed. Adsorption kinetics fit pseudo-second-order models and followed the Langmuir isotherm. Optimal adsorption conditions, identified via Box-Behnken design software, were establish to be a pH of 6 and 0.02 g of CFNF per 25 mL solution. Additionally, the adsorbent demonstrated reusability completed five sequences, show casing stability. This study presents an innovative approach to convert cigarette filter waste into sustainable materials with improved adsorption properties.