scholarly journals Investigation the Effects of Green-Synthesized Copper Nanoparticles on the Performance of Activated Carbon-Chitosan-Alginate for the Removal of Cr(VI) from Aqueous Solution

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2617
Author(s):  
Inas A. Ahmed ◽  
Hala S. Hussein ◽  
Ahmed H. Ragab ◽  
Najla AlMasoud ◽  
Ayman A. Ghfar
Keyword(s):  
Electron Microscopy ◽  
Activated Carbon ◽  
Contact Time ◽  
Sem Analysis ◽  
Adsorption Efficiency ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chromium Vi ◽  
Transmission Electron ◽  
Freundlich Adsorption Isotherm

In the present investigation, green nano-zerovalent copper (GnZVCu), activated carbon (AC), chitosan (CS) and alginate (ALG) nanocomposites were produced and used for the elimination of chromium (VI) from a polluted solution. The nanocomposites GnZVCu/AC-CS-alginate and AC-CS-alginate were prepared. Analysis and characterization were performed by the following techniques: X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The SEM analysis revealed that the nanocomposites are extremely mesoporous, which leads to the greatest adsorption of Cr+6 (i.e., 97.5% and 95%) for GnZVCu/AC-CS-alginate and AC-CS-alginate, respectively. The adsorption efficiency was enhanced by coupling GnZVCu with AC-CS-alginate with a contact time of 40 min. The maximum elimination of Cr+6 with the two nanocomposites was achieved at pH 2. The isotherm model, Freundlich adsorption isotherm and kinetics model and P.S.O.R kinetic models were discovered to be better suited to describe the exclusion of Cr+6 by the nanocomposites. The results suggested that the synthesized nanocomposites are promising for the segregation of Cr+6 from polluted solutions, specially the GnZVCu/AC-CS-alginate nanocomposite.

scholarly journals Biomass-Derived Activated Carbon as a Catalyst for the Effective Degradation of Rhodamine B dye

Processes ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 926
Author(s):  
Shamim Ahmed Hira ◽  
Mohammad Yusuf ◽  
Dicky Annas ◽  
Hu Shi Hui ◽  
Kang Hyun Park
Keyword(s):  
Electron Microscopy ◽  
Activated Carbon ◽  
Rhodamine B ◽  
Photoelectron Spectroscopy ◽  
High Specific Surface Area ◽  
High Porosity ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
X Ray ◽  
Transmission Electron

Activated carbon (AC) was fabricated from carrot waste using ZnCl2 as the activating agent and calcined at 700 °C for 2 h in a tube furnace. The as-synthesized AC was characterized using Fourier-transform infrared spectroscopy, X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller analysis; the results revealed that it exhibited a high specific surface area and high porosity. Moreover, this material displayed superior catalytic activity for the degradation of toxic Rhodamine B (RhB) dye. Rate constant for the degradation of RhB was ascertained at different experimental conditions. Lastly, we used the Arrhenius equation and determined that the activation energy for the decomposition of RhB using AC was approximately 35.9 kJ mol−1, which was very low. Hopefully it will create a great platform for the degradation of other toxic dye in near future.

scholarly journals Crown-Ether-Modified SBA-15 for the Adsorption of Cr(VI) and Zn(II) from Water

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5060
Author(s):  
Jong-Man Yoo ◽  
Sung Soo Park ◽  
Yong-Zhu Yan ◽  
Chang-Sik Ha
Keyword(s):  
Electron Microscopy ◽  
Metal Ions ◽  
Covalent Attachment ◽  
X Ray Diffraction ◽  
X Ray ◽  
Langmuir Adsorption ◽  
Chromium Vi ◽  
Transmission Electron ◽  
Ftir Spectrometry ◽  
Adsorption Desorption

Recently, the release of some metal ions to the environment has been observed to cause serious damages to human health and the environment. Herein, a chromium(VI)- and zinc(II)-selective adsorbent (CB18crown6/SBA-15) was successfully fabricated through the covalent attachment of 4′-carboxybenzo-18-crown-6 (CB18crown6) as a ligand on mesoporous silica support (SBA-15). The CB18crown6/SBA-15 adsorbent was characterized by Fourier-transform infrared (FTIR) spectrometry, X-ray diffraction (XRD), N2 adsorption–desorption, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). To evaluate its ability to selectively capture Cr(VI) and Zn(II), adsorption experiments were conducted. The influences of pH, initial concentration of metal ions, and coexisting metal ions on the adsorption process were examined. The CB18crown6/SBA-15 selectively adsorbed Cr(VI) at pH 2 and Zn(II) at pH 5, respectively, from the mixed aqueous solutions of chromium, zinc, lithium, cadmium, cobalt, strontium, and cesium ions. The data for the adsorption of Cr(VI) onto the CB18crown6/SBA-15 were well explained by the Langmuir adsorption isotherm. In addition, the recycling and reuse of CB18crown6/SBA-15 was successfully achieved, and 71 and 76% reuse efficiency of Cr(VI) and Zn(II), respectively, was obtained after five cycles. This study suggests that the use of the CB18crown6/SBA-15 can be a feasible approach for the selective remediation of Cr(VI) and Zn(II) contamination.

scholarly journals The use of zinc metalloporphyrin grafted magnetic nanoparticles for the removal of sulfate ions from wastewaters

2019 ◽  
Vol 2 (2) ◽  
pp. 65-76
Author(s):  
Tahereh Poursaberi ◽  
Ali Akbar Miran Beigi
Keyword(s):  
Electron Microscopy ◽  
Contact Time ◽  
Optimal Conditions ◽  
X Ray Diffraction ◽  
Sulfate Ions ◽  
X Ray ◽  
Transmission Electron ◽  
Naoh Solution ◽  
Ft Ir ◽  
Scanning Electron

This study investigates an application of zinc metalloporphyrin grafted Fe3O4 nanoparticles as a new adsorbent for removal of sulfate ions from wastewaters. The modification of magnetite nanoparticles was conducted by 3-aminopropyltriethoxysilane followed by zinc (II) porphyrin in order to enhance the removal of sulfate ions. Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) was used to characterize the synthesized nano sorbent. The effect of important experimental factors such as pH, contact time, sorbent dosage and some co-existing anions present in aqueous solutions were investigated. Under optimal conditions (i.e. contact time: 30 min, pH: 6.5 and nanosorbents dosage: 100 mg) for a sulfate sample (50 mL, 50 mgL-1 ) the percentage of the extracted sulfate ions was 94.5%. Regeneration of sulfate adsorbed material could be possible by NaOH solution and the modified magnetic nano sorbent exhibited good reusability.

scholarly journals Nanosized Zincated Hydroxyapatite as a Promising Heterogeneous Photo-Fenton-Like Catalyst for Methylene Blue Degradation

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Van Dat Doan ◽  
Van Thuan Le ◽  
Thi Thanh Nhi Le ◽  
Hoai Thuong Nguyen
Keyword(s):  
Electron Microscopy ◽  
Methylene Blue ◽  
Contact Time ◽  
Degradation Mechanism ◽  
X Ray Diffraction ◽  
Methylene Blue Degradation ◽  
X Ray ◽  
Transmission Electron ◽  
Substitution Degree

This study is devoted to synthesis of nanosized zincated hydroxyapatite (Zn-HA) and its utilization as a heterogeneous photo-Fenton-like catalyst for degradation of methylene blue (MB) in aqueous solution. The prepared catalyst was characterized by various techniques such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray, and Fourier transform infrared spectroscopy. The catalytic activity of Zn-HA towards MB and the effects of various experimental factors such as pH, zinc substitution degrees, initial MB concentration, and H2O2 dosage were studied in detail. The results showed that the zinc substitution degree of 0.4 is optimal to get the highest degradation efficiency under conditions of pH = 10, H2O2 dosage of 0.05 M, and MB concentration of 30 mg/L for a contact time of 120 min. The degradation mechanism was proposed and discussed thoroughly. Besides, the ability of long-term use for the synthesized catalyst was also evaluated.

scholarly journals Reduction of Magnetite in the Presence of Activated Carbon Using Mechanical Alloying

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Ledwaba Harry Moloto ◽  
Sunnyboy Stanley Manzini ◽  
Ezekiel Dixon Dikio
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Activated Carbon ◽  
Mechanical Alloying ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Reduction Behaviour ◽  
Scanning Electron

The reduction behaviour of magnetite using graphite under ball-milling conditions (using a planetary mono mill, Fritsch Pulverisette 6) has been investigated. The reaction of magnetite and graphite at different milling conditions leads to the formation of Fe2+and Fe3+species, the former increasing at the expense of Fe3O4. Fe3O4completely disappeared after a ball to powder ratio of 50 : 1 and beyond. The Fe2+species were confirmed to be due to FeO using Mössbauer Spectroscopy and X-ray diffraction techniques. Scanning electron microscopy and transmission electron microscopy analyses confirm the reduction of magnetite to wüstite.

A High Resolution Study of G.P. Zones in Aluminum - 4.2 at % Silver

1982 ◽  
Vol 40 ◽  
pp. 722-723 ◽  
Author(s):  
R. Gronsky
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Computer Simulations ◽  
Structural Characteristics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Resolution Study

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.

Identification of calcium oxalate crystals in dried or fixed tobacco leaf

1984 ◽  
Vol 42 ◽  
pp. 288-289
Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Growth And Development ◽  
Polarized Light ◽  
Calcium Oxalate Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

The Effect of the Microstructure of Diffusion Barriers on the Palladium Activation for Electroless Copper Deposition

2002 ◽  
Vol 716 ◽  
Author(s):  
Seok Woo Hong ◽  
Yong Sun Lee ◽  
Ki-Chul Park ◽  
Jong-Wan Park
Keyword(s):  
Electron Microscopy ◽  
Diffusion Barriers ◽  
Copper Deposition ◽  
X Ray Diffraction ◽  
Plan View ◽  
X Ray ◽  
Transmission Electron ◽  
Electroless Copper ◽  
Sheet Resistance Measurement ◽  
Scanning Electron

AbstractThe effect of microstructure of dc magnetron sputtered TiN and TaN diffusion barriers on the palladium activation for autocatalytic electroless copper deposition has been investigated by using X-ray diffraction, sheet resistance measurement, field emission scanning electron microscopy (FE-SEM) and plan view transmission electron microscopy (TEM). The density of palladium nuclei on TaN diffusion barrier increases as the grain size of TaN films decreases, which was caused by increasing nitrogen content in TaN films. Plan view TEM results of TiN and TaN diffusiton barriers showed that palladium nuclei formed mainly on the grain boundaries of the diffusion barriers.

Palladium Nanowire Thin Films via Template Growth

2003 ◽  
Vol 775 ◽  
Author(s):  
Donghai Wang ◽  
David T. Johnson ◽  
Byron F. McCaughey ◽  
J. Eric Hampsey ◽  
Jibao He ◽  
...  
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Conductive Substrate ◽  
Palladium Nanowires ◽  
Efficient Route ◽  
Silica Thin Film

AbstractPalladium nanowires have been electrodeposited into mesoporous silica thin film templates. Palladium continually grows and fills silica mesopores starting from a bottom conductive substrate, providing a ready and efficient route to fabricate a macroscopic palladium nanowire thin films for potentially use in fuel cells, electrodes, sensors, and other applications. X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate it is possible to create different nanowire morphology such as bundles and swirling mesostructure based on the template pore structure.

scholarly journals Quartz Crystallite Size and Moganite Content as Indicators of the Mineralogical Maturity of the Carboniferous Chert: The Case of Cherts from Eastern Asturias (Spain)

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 611
Author(s):  
Celia Marcos ◽  
María de Uribe-Zorita ◽  
Pedro Álvarez-Lloret ◽  
Alaa Adawy ◽  
Patricia Fernández ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Crystallite Size ◽  
Archaeological Sites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Infrared And Raman Spectroscopy ◽  
First Time ◽  
Geological Formations

Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.

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