Abstract

A biodegradable material was developed with adsorptive capacity for Cu2+ ions, this material was intended for mining tailings mitigating, environmental impact decrease and economic retribution, for this were elaborated two types of fibers by electrospinning: (1) a cellulose acetate (CA) matrix and (2) a cellulose acetate (CA)/chitosan (CH) matrix evaluating the effect of CH in CA on its physicochemical properties. Through IR-DIRFT the incorporation of chitosan in the matrix was identified, observing the band of the amino group at 1500 - 1600 [cm-1]. By SEM, TEM, Hg porosimetry, and CO2 isotherm at 273 K were identified the intrafiber microporosity and interfiber macroporosity, with an increase in the distribution of macropores for CA/CH fibers. The tensile test indicated that CH in the matrix produces more ductile and tenacious behavior, where the % elongation at break increased by 33% with the other parameters constant. Thermal analysis (DSC and TGA) showed that the incorporation of chitosan produces higher retention of water molecules, decreasing the specific heat and thermoplastic properties of the matrix since the glass transition temperature and softening temperature disappear. Batch adsorption study suggests, the optimum pH was 7 with a qe of 10 mg/g for CA fibers and 12 mg/g for CA/CH fibers. The adsorption study showed, the best isotherm model adapted to the experimental results corresponds to the Sips model and the kinetics study corresponds to pseudo-second order, with an optimum time of 2 h with 50% adsorption. XPS analysis demonstrated that the active centers of complex formation were C2 and C3, associated with amino group (-NH2) and hydroxyl group (-OH) respectively for CA and CA/CH matrix. Finally, the metal competition test (Cu, Cd, Zn, Pb) on AC and CA/CH fibers shows a higher selectivity for Cu2+ cation with a qe of 5.2 mg/g.