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Jyongsik Jang - One of the best experts on this subject based on the ideXlab platform.

  • Heavy Metal Ion adsorptIon behavior in nitrogen doped magnetic carbon nanoparticles isotherms and kinetic study
    Journal of Hazardous Materials, 2011
    Co-Authors: Keunyoung Shin, Jinyong Hong, Jyongsik Jang
    Abstract:

    Abstract To clarify the Heavy Metal adsorptIon mechanism of nitrogen-doped magnetic carbon nanoparticles (N-MCNPs), adsorptIon capacity was investigated from the adsorptIon isotherms, kinetics and thermodynamics points of view. The obtained results showed that the equilibrium adsorptIon behavior of Cr 3+ Ion onto the N-MCNPs can be applied to the Langmuir model and pseudo-second-order kinetics. It indicated that the fabricated N-MCNPs had the homogenous surface for adsorptIon and all adsorptIon sites had equal adsorptIon energies. Furthermore, the adsorptIon onto N-MCNPs taken place through a chemical process involving the valence forces. According to the thermodynamics, the adsorptIon process is spontaneous and endothermic in nature which means that the adsorptIon capacity increases with increasing temperature due to the enhanced mobility of adsorbate molecules. The effects of the solutIon pH and the species of Heavy Metal Ion on the adsorptIon uptake were also studied. The synthesized N-MCNPs exhibited an enhanced adsorptIon capacity for the Heavy Metal Ions due to the high surface area and large amount of nitrogen contents.

  • Heavy Metal Ion adsorptIon onto polypyrrole impregnated porous carbon
    Journal of Colloid and Interface Science, 2008
    Co-Authors: Moonjung Choi, Jyongsik Jang
    Abstract:

    Polypyrrole-impregnated porous carbon was readily synthesized using vapor infiltratIon polymerizatIon of pyrrole monomers. The results show that the functIonalized polymer layer was successfully coated onto the pore surface of carbon without collapse of mesoporous structure. The modified porous carbon exhibited an improved complexatIon affinity for Heavy Metal Ions such as mercury, lead, and silver Ions due to the amine group of polypyrrole. The introduced polypyrrole layer could provide the surface modificatIon to be applied for Heavy Metal Ion adsorbents. Especially, polymer-impregnated porous carbon has an enhanced Heavy Metal Ion uptake, which is 20 times higher than that of adsorbents with amine functIonal groups. Furthermore, the relatIonship between the coated polymer amount and surface area was also investigated in regard to adsorptIon capacity.

Arun Chattopadhyay - One of the best experts on this subject based on the ideXlab platform.

  • quantum dot impregnated chitosan film for Heavy Metal Ion sensing and removal
    Langmuir, 2012
    Co-Authors: Amit Jaiswal, Siddhartha Sankar Ghsoh, Arun Chattopadhyay
    Abstract:

    We report the use of biopolymer-stabilized ZnS quantum dots (Q-dots) for catIon exchange reactIon-based easy sensing and removal of Heavy Metal Ions such as Hg2+, Ag+, and Pb2+ in water. Chitosan-stabilized ZnS Q-dots were synthesized in aqueous medium and were observed to have been converted to HgS, Ag2S, and PbS Q-dots in the presence of corresponding Ions. The transformed Q-dots showed characteristic color development, with Hg2+ being exceptIonally identifiable due to the visible bright yellow color formatIon, while brown coloratIon was observed in other Metal Ions. The catIon exchange was driven by the difference in the solubility product of the reactant and the product Q-dots. The catIon exchanged Q-dots preserved the morphology of the reactant Q-dots and displayed volume increase based on the bulk crystal lattice parameters. The band gap of the transformed Q-dots showed a major increase from the corresponding bulk band gap of the material, demonstrating the role of quantum confinement. Next, we fabr...

Despina Fragouli - One of the best experts on this subject based on the ideXlab platform.

  • Titanate Fibroin Nanocomposites: A Novel Approach for the Removal of Heavy-Metal Ions from water
    ACS Applied Materials & Interfaces, 2017
    Co-Authors: Davide Magrì, Elena Colusso, Alice Scarpellini, Giovanni Perotto, Filippo Drago, Gianvito Caputo, Athanassia Athanassiou, Alessandro Martucci, Despina Fragouli
    Abstract:

    In this study, we report the fabricatIon of nanocomposites made of titanate nanosheets immobilized in a solid matrix of regenerated silk fibroin as novel Heavy-Metal-Ion removal systems. The capacity of these nanocomposite films to remove lead, mercury, and copper catIons from water was investigated, and as shown by the elemental quantitative analysis performed, their removal capacity is 73 mmol/g for all of the Ions tested. We demonstrate that the nanocomposites can efficiently retain the adsorbed Ions, with no release of titanate nanosheets occurring even after several exposure cycles to Ionic solutIons, eliminating the risk of release of potentially hazardous nanosubstances to the environment. We also prove that the introductIon of sodium Ions in the nanocomposite formulatIon makes the materials highly selective toward the lead Ions. The developed biopolymer nanocomposites can be potentially used for the efficient removal of Heavy-Metal-Ion pollutants from water and, thanks to their physical and optica...

Amit Jaiswal - One of the best experts on this subject based on the ideXlab platform.

  • quantum dot impregnated chitosan film for Heavy Metal Ion sensing and removal
    Langmuir, 2012
    Co-Authors: Amit Jaiswal, Siddhartha Sankar Ghsoh, Arun Chattopadhyay
    Abstract:

    We report the use of biopolymer-stabilized ZnS quantum dots (Q-dots) for catIon exchange reactIon-based easy sensing and removal of Heavy Metal Ions such as Hg2+, Ag+, and Pb2+ in water. Chitosan-stabilized ZnS Q-dots were synthesized in aqueous medium and were observed to have been converted to HgS, Ag2S, and PbS Q-dots in the presence of corresponding Ions. The transformed Q-dots showed characteristic color development, with Hg2+ being exceptIonally identifiable due to the visible bright yellow color formatIon, while brown coloratIon was observed in other Metal Ions. The catIon exchange was driven by the difference in the solubility product of the reactant and the product Q-dots. The catIon exchanged Q-dots preserved the morphology of the reactant Q-dots and displayed volume increase based on the bulk crystal lattice parameters. The band gap of the transformed Q-dots showed a major increase from the corresponding bulk band gap of the material, demonstrating the role of quantum confinement. Next, we fabr...

Beibei Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Magnetic chitosan nanocomposites: A useful recyclable tool for Heavy Metal Ion removal
    Langmuir, 2009
    Co-Authors: Xiaowang Liu, Qiyan Hu, Zhen Fang, Xiaojun Zhang, Beibei Zhang
    Abstract:

    Magnetic chitosan nanocomposites have been synthesized on the basis of amine-functIonalized magnetite nanoparticles. These nanocomposites can be removed conveniently from water with the help of an external magnet because of their exceptIonal properties. The nanocomposites were applied to remove Heavy Metal Ions from water because chitosan that is inactive on the surface of the magnetic nanoparticles is coordinated with them. The interactIon between chitosan and Heavy Metal Ions is reversible, which means that those Ions can be removed from chitosan in weak acidic deIonized water with the assistance of ultrasound radiatIon. On the basis of the reasons referred to above, synthesized magnetic chitosan nanocomposites were used as a useful recyclable tool for Heavy Metal Ion removal. This work provides a potential platform for developing a unique route for Heavy Metal Ion removal from wastewater.