Facile Processing of Polyelectrolyte Complexes for Immobilization of Heavy Metal Ions in Wastewater

Abstract

Practical application of polyelectrolyte complexes (PECs) has been limited due to inadequate techniques to overcome processing challenges. This study aimed to explore seamless PEC processing techniques to fabricate adsorbents for wastewater treatment. The phase transition associated with poly(diallyldimethylammonium) and poly(styrenesulfonate) complexes in an aqueous solvent was studied as a function of polymer concentration, charge stoichiometry, and ionic strength. The complex-to-coacervate and coacervate-to-solution phase transitions were observed as the ionic strength increases for all the charge stoichiometries studied. We demonstrate that spherical PEC resins were prepared by injecting the liquid-like coacervates into pure water in a controlled manner. Also, the wastewater treatment experiment revealed that the PEC resins show outstanding performance for heavy metal adsorption with significant uptakes and easy separation. The maximum Pb(II) uptake was measured as 690 ± 0.2 mg/g by the Sips model, and the equilibrium adsorption rate was achieved within ∼2 h. This study thus lays down a protocol for the facile processing of PECs and the fabrication of PEC-based adsorbents for wastewater treatment and related applications.

Efficient Removal of Pb2+ from Water by Bamboo-Derived Thin-Walled Hollow Ellipsoidal Carbon-Based Adsorbent

“…Thus, the pseudo-second-order model is more reliable and accurate for describing the adsorption kinetics for Pb 2+ on CPCs900. These results are consistent with the kinetic model fitting results for pollutant-adsorbent systems reported in the literature. − It has been reported that the adsorption conforming to the pseudo-second-order model is mainly chemical adsorption. − , As such, Pb 2+ adsorption on CPCs900 could be dominated by chemical adsorption.…”

“…We next explore the adsorption kinetics of Pb 2+ on CPCs900. Pseudo-first-order (eq ) and pseudo-second-order (eq ) models have been widely used for analyzing the adsorption kinetics of metal ions on solid materials. − q e and q t are the amounts of metal ions adsorbed on adsorbent at equilibrium and at time t , respectively. k 1 (min –1 ) and k 2 (g mg –1 min –1 ) are rate constants of pseudo-first-order and pseudo-second-order models, respectively .…”

“…33−35 It has been reported that the adsorption conforming to the pseudo-second-order model is mainly chemical adsorption. [30][31][32]36 As such, Pb 2+ adsorption on CPCs900 could be dominated by chemical adsorption.…”

A Brief Review of Gel Polymer Electrolytes Using In Situ Polymerization for Lithium-ion Polymer Batteries

“…The cross-sectional SEM image demonstrated the strong coupling between the cathode and SN-SPE without any discernible delamination ( Figure 8 b). As shown in Figure 8 c, the integrated ASSLIBs had smaller interface resistance than conventional ASSLIBs due to the better interface contact between electrode and electrolyte formed by in situ polymerization [ 104 ].…”

Interfacial stabilization of aqueous two-phase systems: a review

“…on the composition and properties of the coacervate and supernatant phases has emerged. 93 The crowded interiors of the coacervates and their ability to sequester charged (bio)macromolecules from their surroundings have promoted their utility as encapsulants and stabilizers in biological, 79,94 industrial, 95–97 environmental, 17,19,83 and cosmetic applications. 81,82…”