READ-As and GEH sorption materials for the removal of antimony from water

2015 ◽  
Vol 15 (3) ◽  
pp. 525-532 ◽  
Author(s):  
Ján Ilavský ◽  
Danka Barloková ◽  
Pavol Hudec ◽  
Karol Munka
Keyword(s):  
Physical Adsorption ◽  
Mercury Porosimetry ◽  
Surface Characteristics ◽  
Antimony Content ◽  
X Ray ◽  
Filter Materials ◽  
Breakthrough Concentration ◽  
Adsorption Of Nitrogen ◽  
Materials Used ◽  
Pilot Tests

The objective of this work was to verify the sorption properties of granular filter materials (GEH, READ-As) during the process of removing antimony from water. The pilot tests showed that the use of sorption materials could possibly decrease the antimony content in water to the values limited for drinking water (5 μg/L Sb). A more suitable adsorbent for removing antimony was READ-As. At a concentration of antimony in raw water ranging from 21.5 to 31.1 μg/L, a filtration rate of 5.58 m/h, the value of the bed volume of 3,967, and the adsorption capacity of 128.4 μg/g, which was achieved at a breakthrough concentration of 5 μg Sb/L, were determined. The surface characteristics of the sorption materials used through the physical adsorption of nitrogen, mercury porosimetry, X-ray microanalysis, and scanning electron microscopy (SEM) were studied.

Potential Evaluation of Gray Clay as Adsorbent of Heavy Metals Zinc (II) and Lead (II)

2014 ◽  
Vol 798-799 ◽  
pp. 622-627
Author(s):  
Wellington Siqueira Lima ◽  
José Vanderley Nascimento Silva ◽  
Aline Cadigna Lima Patrício ◽  
Guilherme Costa Oliveira ◽  
Meiry Glaúcia Freire Rodrigues
Keyword(s):  
Heavy Metals ◽  
Factorial Design ◽  
Metal Removal ◽  
Physical Adsorption ◽  
X Ray Diffraction ◽  
X Ray ◽  
Removal Capacity ◽  
Adsorption Of Nitrogen ◽  
Potential Evaluation ◽  
Good Percentage

The problems caused by contamination of heavy metals generate a growing need to implement technologies to reduce or eliminate them. This work aims to evaluate the potential of gray clay, the process of removal of zinc and lead from synthetic effluents in finite bath system. The clay was characterized by: X-ray diffraction, X-ray Spectroscopy Energy Dispersive and Physical Adsorption of Nitrogen. The tests were performed finite bath following a 22 factorial design, with the variables: pH and initial concentrations of metal. The clays were evaluated for their removal capacity and rate of metal removal. After the characterization and evaluation, it was found that the gray clay comprises clay of the groups of kaolinite and mica. The results of the factorial design shown that the adsorption of the metals zinc and lead can be developed with good percentage of removal.

Synthesis of Ni-Mo-W Sulfide Nanorods as Catalyst for Hydrodesulfurization of Dibenzothiophene

2008 ◽  
Vol 8 (12) ◽  
pp. 6406-6413 ◽  
Author(s):  
F. Paraguay-Delgado ◽  
R. García-Alamilla ◽  
J. A. Lumbreras ◽  
E. Cizniega ◽  
G. Alonso-Núñez
Keyword(s):  
Electron Microscopy ◽  
Physical Adsorption ◽  
Atomic Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Oxide Precursor ◽  
Transmission Electron ◽  
Adsorption Of Nitrogen ◽  
Diffraction Patterns ◽  
Scanning Electron

Two trimetallic sulfurs, MoWNiS and MoWSNi, were synthesized to be used as a catalyst in hydrodesulfurization reactions. The mixed oxide mesoporous nanostructured MoO3-WO3 with an Mo:W atomic ratio of 1:1 was used as the precursor. The first catalyst was prepared by impregnating nickel in the oxide precursor and then subsequent sulfiding with an H2S/H2 mix at 400 °C for 2 hours. The second catalyst was prepared by sulfiding the precursor and then impregnating the nickel, and finally reducing the material with a H2/N2 at 350 °C. In both catalysts the Mo:W:Ni atomic ratio was maintained at 1:1:0.5. The materials obtained were characterized by physical adsorption of nitrogen, X-ray diffraction, scanning electron microscopy, transmission electron microscopy. Furthermore, the materials obtained were evaluated by a dibenzothiophene hydrodesulfuration reaction. The diffraction patterns show that both materials are polycrystalline and mainly of MoS2 and WS2 phases.

SYNTHESIS OF NANOSTRUCTURED POROUS CARBON

2005 ◽  
Vol 04 (02) ◽  
pp. 261-268 ◽  
Author(s):  
FABING SU ◽  
LU LV ◽  
X. S. ZHAO
Keyword(s):  
Porous Carbon ◽  
Carbon Materials ◽  
Physical Adsorption ◽  
High Surface ◽  
High Surface Area ◽  
Microscopic Structure ◽  
X Ray ◽  
Transmission Electron ◽  
Adsorption Of Nitrogen ◽  
Scanning Electron

In this paper, high-surface-area porous carbons with crumpled nanowalls were synthesized by carbonization of sucrose in the presence of zeolite template. The pore structures of the carbon materials were characterized using physical adsorption of nitrogen. Their surface chemistry was analyzed using X-ray photoelectron spectrometer (XPS). The microscopic structure features of the samples were imaged by field-emission scanning electron microscope (FESEM) and transmission electron microscopy (TEM). The nanostructure of synthesized porous carbon with a combination of micro-, meso- and macropores has been obtained.

Evaluation of Bentonite Clay Type in the Chocobofe Zinc Adsorption in Finite Bath System

2015 ◽  
Vol 820 ◽  
pp. 539-544
Author(s):  
J.V. do N. Silva ◽  
Janaína Rafaella Scheibler ◽  
M.G.F. Rodrigues
Keyword(s):  
Physical Adsorption ◽  
Bentonite Clay ◽  
Exchange Capacity ◽  
X Ray Diffraction ◽  
Promising Alternative ◽  
X Ray ◽  
Smectite Clays ◽  
Bet Method ◽  
Adsorption Of Nitrogen ◽  
Percentage Removal

In this work the smectite clays Chocobofe from the state of Paraíba was investigated to evaluate their affinity and capacity for removal of zinc using a finite bath system. The clay was characterized by means of X-Ray Diffraction (XRD), Infrared Spectroscopy in the Region (IV) and Cation Exchange Capacity (CEC) and Physical Adsorption of Nitrogen (BET method). A 22 factorial design was conducted with three center points in a finite bath system to determine the percentage removal (% Rem) and removability (qeq) of the clay. Values of 83.35 to 98.83% and the percentage removal from 3.83 to 4.24 mg / g removal were achieved in experiments, indicating that the use of clay Chocobofe appears as a promising alternative to remove of Zn2+

Photocatalytic activity of TiO2 synthesized by anodization and anodic spark deposition

MRS Advances ◽  
2020 ◽  
Vol 5 (61) ◽  
pp. 3141-3152
Author(s):  
Alma C. Chávez-Mejía ◽  
Génesis Villegas-Suárez ◽  
Paloma I. Zaragoza-Sánchez ◽  
Rafael Magaña-López ◽  
Julio C. Morales-Mejía ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Surface Characteristics ◽  
Amorphous Solids ◽  
X Ray Diffraction ◽  
X Ray ◽  
Catalytic Activities ◽  
Anodic Spark Oxidation ◽  
Porous Surfaces ◽  
Scanning Electron

AbstractSeveral photocatalysts, based on titanium dioxide, were synthesized by spark anodization techniques and anodic spark oxidation. Photocatalytic activity was determined by methylene blue oxidation and the catalytic activities of the catalysts were evaluated after 70 hours of reaction. Scanning Electron Microscopy and X Ray Diffraction analysis were used to characterize the catalysts. The photocatalyst prepared with a solution of sulfuric acid and 100 V presented the best performance in terms of oxidation of the dye (62%). The electric potential during the synthesis (10 V, low potential; 100 V, high potential) affected the surface characteristics: under low potential, catalyst presented smooth and homogeneous surfaces with spots (high TiO2 concentration) of amorphous solids; under low potential, catalyst presented porous surfaces with crystalline solids homogeneously distributed.

scholarly journals Study on Adsorption Properties of Modified Corn Cob Activated Carbon for Mercury Ion

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4483
Author(s):  
Yuyingnan Liu ◽  
Xinrui Xu ◽  
Bin Qu ◽  
Xiaofeng Liu ◽  
Weiming Yi ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Photoelectron Spectroscopy ◽  
Adsorption Process ◽  
Physical Adsorption ◽  
Raw Material ◽  
Order Kinetic ◽  
Mercury Ions ◽  
Corn Cob ◽  
Adsorption Time ◽  
X Ray

In this study, corn cob was used as raw material and modified methods employing KOH and KMnO4 were used to prepare activated carbon with high adsorption capacity for mercury ions. Experiments on the effects of different influencing factors on the adsorption of mercury ions were undertaken. The results showed that when modified with KOH, the optimal adsorption time was 120 min, the optimum pH was 4; when modified with KMnO4, the optimal adsorption time was 60 min, the optimal pH was 3, and the optimal amount of adsorbent and the initial concentration were both 0.40 g/L and 100 mg/L under both modified conditions. The adsorption process conforms to the pseudo-second-order kinetic model and Langmuir model. Scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and Zeta potential characterization results showed that the adsorption process is mainly physical adsorption, surface complexation and ion exchange.

scholarly journals Characterization of calcium oxide in root perforation sealer materials

2012 ◽  
Vol 23 (5) ◽  
pp. 539-546 ◽  
Author(s):  
Carlos Estrela ◽  
Manoel Damião Sousa-Neto ◽  
Orlando Aguirre Guedes ◽  
Ana Helena Gonçalves Alencar ◽  
Marco Antonio Hungaro Duarte ◽  
...  
Keyword(s):  
Calcium Oxide ◽  
Mineral Trioxide Aggregate ◽  
Chemical Compounds ◽  
Internal Diameter ◽  
X Ray ◽  
Final Sample ◽  
Materials Used ◽  
Main Components ◽  
White Mineral

Root perforation represents an undesirable complication that may lead to an unfavorable prognosis. The aims of this study were to characterize and to compare the presence of calcium oxide (CaO) on the chemical composition of materials used for root perforation therapy: gray and white mineral trioxide aggregate (MTA) and Portland cement (PC), gray MTA+5%CaO and gray MTA+10%CaO. The last two materials were analyzed to evaluate the increase of CaO in the final sample. CaO alone was used as a standard. Eighteen polyethylene tubes with an internal diameter of 3 mm and 3 mm in length were prepared, filled and then transferred to a chamber with 95% relative humidity and a temperature of 37ºC. The chemical compounds (particularly CaO) and the main components were analyzed by energy-dispersive X-ray microanalysis (EDX). EDX revealed the following concentrations of CaO: gray MTA: 59.28%, white MTA: 63.09%; PC: 72.51%; gray MTA+5%CaO: 63.48% and gray MTA+10%CaO: 67.55%. The tested materials presented different concentrations of CaO. Even with an increase of 5 and 10% CaO in gray MTA, the CaO levels found in the MTA samples were lower than those found in PC.

Removal of Heavy Metal Ions from Aqueous Solution by Manganese Dioxide-Coated Polypropylene Granules: An Implication of Rainwater Runoff Treatment

2007 ◽  
Vol 544-545 ◽  
pp. 131-134
Author(s):  
Sardor Abdukakharovich Mavlyankariev ◽  
Dong Seok Rhee
Keyword(s):  
Metal Ions ◽  
Manganese Dioxide ◽  
Surface Area ◽  
Mercury Porosimetry ◽  
Surface Characteristics ◽  
Metal Species ◽  
Adsorption Model ◽  
Rainwater Runoff ◽  
Flow Through ◽  
Fast Removal

Modified polypropylene granules (MDPG) were coated by manganese dioxide and their surface and adsorptive characteristics were studied. Surface characteristics of the adsorbent were investigated by B.E.T. surface area and mercury porosimetry. Coating has significantly increased the surface area of granules from 0.12 m 2 /g B.E.T. N 2 to 15.42 m 2 /g. Gas pycnometry measurements resulted in low density of 0.13 g/cm 3 for uncoated granules, the fact ascribed to 0.65 porosity measured. Coating increased micro pore volume of raw granules by a factor of 58. Adsorption experiments were conducted in column flow-through reactors at pH 6.0 and 10 g/L sorbent dosage for mixture of four metal species, each having 5 mg/L initial concentration. More than 60 % of Pb and Cu was removed within first 20 min, whereas just over 29 and 13 % for Cd and Zn respectively. Furthermore, more than 99, 84, 40, 16 % of Pb, Cu, Cd, and Zn was removed within 1 h. Adsorption efficiencies for 5 ppm of initial metal concentration at pH 5.0 and 10 g/L sorbent/solute ratio resulted in 4.9, 3.9 mg of Pb and Cu sorbed per gram of sorbent. And these ratios for separate metal ions were substantially higher than those for the mixture of the four metal ions. For 5 g/L of sorbent under the same parameters, removal efficiencies of Cd and Zn were respectively 0.98, 0.75 mg/g, correlating well with Freundlich adsorption model. Adsorption kinetics showed relatively fast removal rates within first 5 h of sorption. Desorption resulted in eluting 57, 70, 76, 78 % of the initial feeding concentrations for Pb, Cu, Cd, Zn, respectively.

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