Fe۳O۴/Polystyrene-Alginate Nanocomposite as a Novel Adsorbent for Highly Efficient Removal of Dyes

In this study, Fe۳O۴/polystyrene-alginate nanocomposite with high adsorption capacity was successfully prepared. Characterization of Fe۳O۴/polystyrene-alginate nanocomposite was carried out by various instruments, including SEM, EDX, FT-IR, XRD, and TGA. Then, the prepared nanocomposite was applied to remove malachite green as a cationic dye from aqueous solutions. The kinetic study was performed and the results showed the suitability of the pseudo-second-order kinetic model (R۲ = ۰.۹۹۴). The influence of different parameters, such as initial dye concentration, solution pH, adsorbent dosage, and contact time on the procedure was extensively investigated. The maximum adsorption of malachite green onto Fe۳O۴/polystyrene-alginate nanocomposite was found at an initial concentration of ۲۰ mg/L, pH ۷, adsorbent’s dosage ۵۰۰ mg/L, contact time equal to ۲۰ min. To understand the nature of the adsorption procedure, the equilibrium adsorption isotherms were investigated. The linear correlation coefficients of Langmuir and Freundlich isotherms were obtained. The adsorption of malachite green was better fitted to Langmuir isotherm (R۲ = ۰.۹۹۶). According to the Langmuir isotherm model, the maximum adsorption capacity of Fe۳O۴/polystyrene-alginate nanocomposite for sequestering malachite green was about ۹۰.۸۱ mg/g. In addition, negative ΔG۰ and ΔH۰ values obtained through thermodynamic investigation implied that the adsorption of malachite green onto Fe۳O۴/polystyrene-alginate nanocomposite was simultaneous and exothermic in nature, respectively.

کلیدواژه ها:

Fe۳O۴/polystyrene-alginate nanocomposite ، Malachite green ، Operational parameters ، Adsorption isotherms ، Thermodynamic investigation