Synthesis, characterization, and utilization of poly-amino acid-functionalized lignin for efficient and selective removal of lead ion from aqueous solution

Mannich Reaction: Review of Amine‐Functionalized Lignin Derivatives and Their Applications

“…Lin et al. established γ‐polyglutamic acid (γ‐PGA) and ϵ‐poly‐L‐lysine (ϵ‐PL) functionalized lignin (DLGS and DLLS) employing soda lignin (Figure 5A) via demethylation, phenolation and amination for removal of Pb 2+ from polluted water [28] . The prepared DLGS and DLLS showed 275.9 (40 min) and 231.8 (60 min) mg/g adsorption, following pseudo‐second‐order and Langmuir isotherm models.…”

“…A. Synthesis of γ-polyglutamic acid (DLGS) and ε-poly-L-lysine (DLLS) functionalized lignin Reproduced from ref. [28], copyrights (2022), with permission from Elsevier and B). The synthesis of lignin-based magnetic adsorbents (L1@MNP and L2@MNP), Reproduced from ref.…”

Lignin‐based materials for the detection and adsorption of metal ions

“…A detailed proposed mechanism is shown in Figure 10, wherein the phenol moieties after demethylation were assumed to be oxidized to form carboxylate that can bind well to chromium ions. In another work, lignin could be functionalized with two polyamino acids: polyglutamic acid having carboxyl groups and polylysine having amino groups 74 . The synthesis began with lignin modification, wherein acidic phenolation and demethylation were able to afford the high content of phenol groups on lignin (Figure 11).…”

“…Chemical modification of lignin with polypeptide and dithiocarbamate. Reproduced with permission from Reference 74. Copyright 2022 Elsevier Ltd.…”

Selective capacitive removal of Pb2+ ion contaminants from drinking water via nickel foam/Mn2CoO4@tannic acid-Fe3+ electrodes

“…7 Among the many water treatment technologies for removing heavy metal ions, adsorption has been studied more because of its technical advantages of high efficiency and simple operation compared with co-precipitation chemical and ion exchange methods. 8 Researchers have developed a variety of new adsorption materials, such as the combination of pyridine rings and carboxyl groups in porous aromatic frameworks, 9 poly(amino acid)-functionalized lignins, 10 polymerization of dopamine in the pore structures of metal-organic frameworks, 11 amorphous hydrous manganese dioxide, 12 chemical immobilization of tetrathiomolybdate on Fe 3 O 4 nanoparticles in situ, 13 sulfatedoped flower-like layered double oxides and others that can all achieve the selective adsorption of Pb 2+ . 14 However, this technology still faces some drawbacks, such as difficult recovery, limited stability in solution and limited efficiency at low concentrations.…”