Dong Nguyen Thanh

Publications (4) View all

• Article: As(V) removal from aqueous media using alpha-MnO(2) nanorods-impregnated laterite composite adsorbents

  Dong Nguyen Thanh, Mandeep Singh, Pavel Ulbrich, Frantisek Stepanek, Nina Strnadova
  Materials Research Bulletin. 01/2012; 47(1):42-50.
• Article: Perlite incorporating γ-Fe2O3 and α-MnO2 nanomaterials: Preparation and evaluation of a new adsorbent for As(V) removal

  Dong Nguyen Thanh etal
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  ABSTRACT: Novel composite adsorbents for As(V) removal from aqueous solution were synthesized by successfully incorporating α-MnO2 nanorods and γ-Fe2O3 nanoparticles onto ball-milled expanded perlite carrier material. The composite adsorbents were characterized using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Powder X-ray diffraction (XRD) and Brunauer–Elmet–Teller nitrogen adsorption (BET-N2 adsorption). The BET surface area of ball-milled expanded perlite increased by 4.0 and 7.1 times after the incorporation of γ-Fe2O3 and α-MnO2 nanomaterials. The adsorption capacity for As(V) was found to be highly pH dependent and the adsorption kinetics followed the pseudo-second-order kinetic model. The Langmuir isotherm was found to be the best model to describe the adsorption of As(V) on both composites and the adsorption capacity was 4.64 and 7.09 mg g−1 for γ-Fe2O3 and α-MnO2 containing adsorbents as compared to 0.0025 mg g−1 for perlite alone, confirming that these composites retain the constituent nanomaterial properties while being macroscopic particles suitable for arsenic removal in water treatment technology.
  Separation and Purification Technology 10/2011; · 2.92 Impact Factor
• Article: Perlite incorporating gamma-Fe(2)O(3) and alpha-MnO(2) nanomaterials: Preparation and evaluation of a new adsorbent for As(V) removal

  Dong Nguyen Thanh, Mandeep Singh, Pavel Ulbrich, Nina Strnadova, Frantisek Stepanek
  Separation and Purification Technology 01/2011; 82:93-101. · 2.92 Impact Factor
• Article: Synthesis, characterization and study of arsenate adsorption from aqueous solution by α- and δ-phase manganese dioxide nanoadsorbents

  Mandeep Singh, Dong Nguyen Thanh, Pavel Ulbrich, Nina Strnadová, František Štěpánek
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  ABSTRACT: Single-phase α-MnO2 nanorods and δ-MnO2 nano-fiber clumps were synthesized using manganese pentahydrate in an aqueous solution. These nanomaterials were characterized using the Transmission Electron Microscope (TEM), Field Emission Scanning Electron Microscope (FE-SEM), Powder X-ray diffraction (XRD) and the Brunauer–Elmet–Teller nitrogen adsorption technique (BET-N2 adsorption). The structural analysis shows that α-MnO2 (2×2 tunnel structure) has the form of needle-shaped nanorods and δ-MnO2 (2D-layered structure) consists of fine needle-like fibers arranged in ball-like aggregates. Batch adsorption experiments were carried out to determine the effect of pH on adsorption kinetics and adsorption capacity for the removal of As(V) from aqueous solution onto these two types of nanoadsorbents. The adsorption capacity of As(V) was found to be highly pH dependent. The adsorption of As(V) onto α-MnO2 reached equilibrium more rapidly with higher adsorption capacity compared to δ-MnO2.Graphical abstractα-MnO2 (2×2 tunnel structure) nanorods and δ-MnO2 (2-D layered structure) nano-fiber clumps were synthesized in a facile way in an aqueous solution and characterized by TEM, FE-SEM, XRD and BET-N2 adsorption techniques. The structural analysis shows that α-MnO2 is needle shaped nanorods and δ-MnO2 consists of 2-D platelets of fine needle-like fibers arranged in ball-like aggregates. Further batch experiments confirmed that both nanoadsorbents are potential candidates for the adsorption of As(V) with a capacity of 19.41 and 15.33 mg g−1 for α-MnO2 and δ-MnO2, respectively. The presence of As3d peak in XPS study indicates that arsenic on the surface of nanoadsorbents is in the stable form of As(V) with a percentage of arsenate onto α-MnO2 is 0.099% as compared to 0.021% onto δ-MnO2, clearly indicating the higher adsorption of As(V) in case of α-MnO2 as compared to δ-MnO2, which is in good agreement with the adsorption studies results.
  Journal of Solid State Chemistry. 183(12):2979-2986.