Self-assembly of polyelectrolytes for the removal of metal cations from aqueous solutions

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

“…It is noted that the pseudo-second-order model gives better correlation for the Pb­(II) adsorption onto the resins than the pseudo-first-order model . Considering that the pseudo-second-order model describes chemisorption kinetics, this reflects that the adsorption is induced by chelation and electrostatic attractions between the PEC resins and metal ions. , …”

“…The metal adsorption of the PEC resins is mainly attributed to the stronger electrostatic affinity of the anionic sulfonate group to cationic metal ions than potassium ions and a chelation reaction provided by the quaternary ammonium group of PDADMA . To understand the metal binding mechanisms, a potassium ion leaching test was carried out in which the amount of potassium ions released from the PEC resins was measured in deionized water and Pb­(II)-bearing wastewater (see Figure S12).…”

“…While most investigations dealing with processing PECs have focused on the possibility of the shape designs and their potential applications, much less have demonstrated the practical applications of the PECs. Because of charged nature, the PECs have potential for immobilizing metal ions in aqueous media, yet they are insoluble at lower ionic strength; both characteristics are required for effective water/wastewater treatment. − Among the various types of water pollutants, heavy metals, usually exposed to the environment through the industrial activities of agriculture, pharmaceutical, mining, and energy production, pose significant threats to human health and ecological environments due to their non-biodegradability and accumulation in living cells. − Even dilute concentrations can cause intense carcinogenic and other adverse health effects such as encephalopathy (brain dysfunction), nephropathy (kidney disease), anemia, chalcosis of the eye, and metal poisoning. ,, Therefore, it is necessary to maintain all wastewaters below acceptable concentration limits of the heavy metals prior to discharging into water bodies. , While the heavy metal ions can be removed by adsorption, solvent extraction, chemical precipitation, membrane separation, and cementation, , the adsorption is significantly favorable owing to low cost, simplicity of operation, high efficiency, and limited secondary pollution. ,− Few notable studies have shown immobilizations of metal complexes by adding polyelectrolytes into the wastewater solutions and subsequent precipitation of the polyelectrolyte–metal complexes. , The main drawback of this approach is difficult separation after use, which requires advanced gravity separation and ultrafiltration technique.…”

Humics‐based interpolyelectrolyte complexes for antierosion protection of soil: Model investigation

“…). On the other hand, it follows from the literature(Boamah et al, 2015;Zhao, Wang, Zhang, Gu, & Gao, 2018) divalent metal ions typically form two ionic bonds with carboxylic groups of water-soluble polymers. This offers another way to calculate the saturating Cu 2+ concentration (column 5).The table shows different results for the two approaches.The next step was to study the NIPEC interaction with a synthetic hydrophilic colloid regarded as a simple soil model.…”