Electrospun Cellulose Acetate/Polyethylenimine Porous Fibers toward Highly Efficient Removal of Cr(VI)

Abstract

The development of an efficient, economical, and environmentally friendly monolithic adsorbent for the removal of toxic hexavalent chromium Cr­(VI) has invariably been a topic of great concern to researchers. In this paper, cellulose acetate (CA) and polyethylenimine (PEI) homogeneously blending porous fiber membranes with high porosity were successfully prepared by electrospinning, and PEI was further immobilized by cross-linking to form a stable biological adsorbent. The adsorption behavior and eliminating mechanism toward Cr­(VI) by the CA-c-PEI fibrous membranes were comprehensively explored. The maximum adsorption capacity was up to 285.7 mg/g (25 °C), higher than most of the biomass-based adsorbents. Specifically, the concentration of Cr­(VI) could be dramatically reduced from the initial 50 mg/L to 0.03 mg/L, much lower than the concentration standard for drinking water recommended by the World Health Organization. Even after being reused several times, the fibrous membrane still exhibited high removal efficiency.

Biomimetic Polylactic Acid Electrospun Fibers Grafted with Polyethyleneimine for Highly Efficient Methyl Orange and Cr(VI) Removal

“…40 The Cr 2p3/2 orbital also has two peaks, which are located at 576.6 and 578.7 eV, corresponding to the Cr(III) 2p3/2 orbital and the Cr(VI) 2p3/2 orbital, respectively. 80,81 It proves that LDF-3-70000 can reduce part of Cr(VI) to Cr(III). By calculating the corresponding peak areas of Cr(III) and Cr(VI), the atomic ratio of Cr(III) and Cr(VI) is 1.84:1, which indicates that LDF-3-70000 has strong reducibility, and 64.79% of the adsorbed Cr(VI) is reduced to Cr(III).…”

Diatomite-Based Adsorbent Decorated with Fe3O4 Nanoparticles for the Removal of Hazardous Metal Ions

“…Among them, the adsorption equilibrium constant K eq was obtained from Liu’s isotherm model, and the linear fitting results are shown in Figure g–i and Table S4. The values of Δ S ° were positive for Pb 2+ , Ni 2+ , and Cd 2+ , indicating that the adsorption process exhibits an increase in disorder at the solid/liquid interface and reflecting the potential structural adaptability in metal ions and MTDSA. , The positive value of Δ H ° implies that the adsorption is endothermic, which is consistent with analysis of the adsorption isotherms in that the increased temperature favors this adsorption process. Δ G ° decreased with an increase in the temperature, demonstrating that the whole adsorption process is spontaneous and the adsorption is more favorable at high temperature.…”

Synchronously Enhanced Removal Ability and Stability of MXene through Biomimetic Modification

“…To date, various means have been developed to remove heavy-metal ions from wastewater. These strategies include ion exchange, membrane separation, membrane filtration, photocatalytic degradation, chemical precipitation, adsorption, − etc. Among the above methods, the adsorption method is considered the most effective one, because it has the advantages of low cost, high removal efficiency, and easy recycling, and specifically, various substances may be adsorbed simultaneously.…”