scholarly journals Removal of Aniline and Benzothiazole Wastewaters Using an Efficient MnO2/GAC Catalyst in a Photocatalytic Fluidised Bed Reactor

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5207
Author(s):  
Cristian Ferreiro ◽  
Natalia Villota ◽  
José Ignacio Lombraña ◽  
María J. Rivero ◽  
Verónica Zúñiga ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Metal Oxide ◽  
Manganese Dioxide ◽  
Reaction Times ◽  
Fluorescence Analysis ◽  
Active Phase ◽  
Fluidised Bed ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Fluidised Bed Reactor

This work presents an efficient method for treating industrial wastewater containing aniline and benzothiazole, which are refractory to conventional treatments. A combination of heterogeneous photocatalysis operating in a fluidised bed reactor is studied in order to increase mass transfer and reduce reaction times. This process uses a manganese dioxide catalyst supported on granular activated carbon with environmentally friendly characteristics. The manganese dioxide composite is prepared by hydrothermal synthesis on carbon Hydrodarco® 3000 with different active phase ratios. The support, the metal oxide, and the composite are characterised by performing Brunauer, Emmett, and Teller analysis, transmission electron microscopy, X-ray diffraction analysis, X-ray fluorescence analysis, UV–Vis spectroscopy by diffuse reflectance, and Fourier transform infrared spectroscopy in order to evaluate the influence of the metal oxide on the activated carbon. A composite of MnO2/GAC (3.78% in phase α-MnO2) is obtained, with a 9.4% increase in the specific surface of the initial GAC and a 12.79 nm crystal size. The effect of pH and catalyst load is studied. At a pH of 9.0 and a dose of 0.9 g L−1, a high degradation of aniline and benzothiazole is obtained, with an 81.63% TOC mineralisation in 64.8 min.

Effect of Silicon on High Temperature Oxidation Of Stainless Steels★

CORROSION ◽  
1959 ◽  
Vol 15 (11) ◽  
pp. 73-77 ◽  
Author(s):  
JOHN F. RADAVICH
Keyword(s):  
Metal Oxide ◽  
Oxide Scale ◽  
Oxidation Resistance ◽  
Stainless Steels ◽  
Oxide Films ◽  
Fluorescence Analysis ◽  
X Ray Diffraction ◽  
Oxide Interface ◽  
Temperature Oxidation ◽  
X Ray

Abstract Growth of oxide films at 600 and 800 C on a series of 16 Cr-10 Ni-bal Fe stainless steels with silicon contents ranging from 0.17 to 3.55 percent was studied by electron microscopy, electron diffraction, X-ray diffraction and X-ray fluorescence analysis techniques. Oxide scales and sub-scales formed during oxidation at 1000 C were studied optically in cross section as well as by X-ray diffraction and fluorescence analysis. Results show that as silicon content increases oxidation resistance increases rapidly until at the high silicon level, 3.55 percent, a very thin oxide film is formed at 60u and 800 G and very little oxide scale forms at 1000 C. Mechanism of oxidation resistance imparted by silicon appears to be that it decreases the number of defects in the initial oxide films formed at the metal-oxide interface. With a lesser number of defects in the thin film, an enrichment of Cr at the metal-oxide interface and in the oxide films occurs and the rate of diffusion of iron outward to form the oxide scale is greatly retarded. 2.3.7

scholarly journals Synthesis and characterization of antibacterial magnetite-activated carbon nanoparticles

2019 ◽  
Vol 44 (1-2) ◽  
pp. 80-87
Author(s):  
Roonak Golabiazar ◽  
Zagros A Omar ◽  
Rekar N Ahmad ◽  
Shano A Hasan ◽  
S Mohammad Sajadi
Keyword(s):  
Electron Microscopy ◽  
Fourier Transform ◽  
Activated Carbon ◽  
Carbon Nanoparticles ◽  
Fourier Transform Infrared ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphological Studies ◽  
Vis Spectroscopy

Magnetite iron oxide nanoparticles synthesized using the co-precipitation methods were further functionalized with activated carbon. The magnetite-activated carbon nanoparticles were characterized by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and UV-Vis spectroscopy. X-ray diffraction and Fourier transform infrared confirmed the functionalization of the Fe3O4 nanoparticles with the activated carbon. The X-ray diffraction studies demonstrate that magnetite-activated carbon nanoparticles were indexed into the spinel cubic lattice with a lattice parameter of 0.833 nm and an average particle size of about 14 nm. Various parameters such as dislocation density, microstrain, and surface morphological studies were calculated. However, this work implicated the use of magnetite-activated carbon nanoparticles in antibacterial studies. Further, the antibacterial effect of magnetite-activated carbon nanoparticles was evaluated against three pathogenic bacteria, which showed that the nanoparticles have moderate antibacterial activity against both Gram-positive ( Staphylococcus aureus) and Gram-negative ( Proteus mirabilis and Pseudomonas aureginosa) pathogenic bacterial strains in the presence of different magnetite-activated carbon nanoparticle concentrations at room temperature.

Metal complexes supported on activated carbon as catalysts for the hydrogenation of anthracene

2017 ◽  
Vol 15 (5) ◽  
Author(s):  
Liliana Giraldo ◽  
Moreno-Piraján ◽  
John J. Hurtado
Keyword(s):  
Catalytic Activity ◽  
Activated Carbon ◽  
Supported Catalysts ◽  
Reaction Times ◽  
Chemical Characteristics ◽  
Distribution Analysis ◽  
X Ray ◽  
Different Temperatures ◽  
Surface Area Determination ◽  
Area Determination

Abstract In this work, the catalytic activity was investigated in the hydrogenation of anthracene by BaSO3 and Cu(II), Zn(II) and Ni(II) complexes that contain the ligand bis(3,5-dimethyl-1-pyrazolyl) methane (L). The compounds were supported on activated carbon (AC) and studied as catalysts for the hydrogenation of anthracene over different temperatures and reaction times. The supported catalysts (Cat/AC) were prepared by direct impregnation on the support and characterized by surface area determination, FTIR spectroscopy, and X-ray powder diffraction and pore size distribution analysis. The results showed high conversions and selectivity toward hydrogenated products, where the highest value was obtained using LNiCl2/AC and the lowest with BaSO3/AC. It was established that the selectivity for Tetrahydroanthracene was more highest quantity as a product of hydrogenation using Cat/AC which is dependent of the temperature, reaching a peak at 450 °C. At this temperature and with very short reaction times, the catalytic activity is influenced mainly by the chemical characteristics of the metal in the complexes and the AC support.

Synthesis and Characterization of Mg(OH)2-Impregnated Activated Carbon Adsorbent from Coconut Shell

2019 ◽  
Vol 948 ◽  
pp. 49-53
Author(s):  
Andri Saputra ◽  
Hary Sulistyo ◽  
Deni Swantomo
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Carbon Adsorbent ◽  
Fluorescence Analysis ◽  
Coconut Shell ◽  
X Ray ◽  
Impregnation Ratio ◽  
Bet Method ◽  
Treated Carbon

Introducing or impregnating Mg(OH)2onto activated carbon is a promising path for wastewater treatment of uptake (removal) uranium from aqueous solution. The present study aims to synthesize and characterize Mg(OH)­2-impregnated activated carbon from coconut shell. The introducing or impregnating Mg(OH)2into treated biochar by activation method using various impregnation ratio (IR) of MgCl2(IR = 0.5; 1.0; 2.0). Characterization of functional groups in produced activated carbon was conducted with the aid of FTIR spectroscopy. The presence of O-H or Mg(hydroxyl) bond was confirmed by FTIR analysis at 3343.50 cm-1with the highest intensity of the obtained peak at impregnation ratio (IR) 2.0. Due to the surface area is one of the important factors that control a material’s ability to adsorb contaminations, the surface area of activated carbon was measured about 353-358 m2/g by BET method. To indicate that introducing or impregnating Mg(OH)2or Mg(hydroxyl) into treated carbon is successfully work, the presence of Mg (%w) in activated carbon was performed using X-Ray Fluorescence Analysis with the highest Mg presence about 28.587 (%w) at impregnation ratio (IR) 2.0.

scholarly journals Removal of Congo Red Dye using Synthesised Copper(II) Activated Carbon from Date Seeds

2021 ◽  
Vol 14 ◽  
pp. 1-9
Author(s):  
Nur rahimah Said ◽  
Hazirah Syahirah Zakria ◽  
Siti Nor Atika Baharin ◽  
Nurul' Ain Jamion
Keyword(s):  
Activated Carbon ◽  
Surface Area ◽  
Congo Red ◽  
Bet Surface Area ◽  
Activation Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Effective Removal ◽  
Vis Spectroscopy ◽  
Red Dye

Azo dyes are recognised as contaminants from the textile and printing industries that lead to human toxicity. Copper(II) activated carbon (CuAC) is an effective removal agent of dyes in these industries. The purpose of this study is to synthesise and characterise CuAC from date seeds. In addition, the efficiency of CuAC as a removal of Congo red (CR) in aqueous solution is also studied. Activated carbon (AC) was prepared from date seeds using phosphoric acid as activating agent, followed by activation process in a furnace at 500 ℃ for 2 hours. Copper(II) nitrate was used in the impregnation of AC to produce CuAC. The AC and CuAC were characterised using Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy (ATR-FTIR), BET surface area (SBET), Scanning Electron Microscope-Energy Dispersive X-Ray Spectroscopy (SEM-EDX), Atomic Absorption Spectroscopy (AAS) and X-Ray Diffraction (XRD). UV-VIS Spectroscopy was used to determine dye concentrations after treatment with removal agent of CuAC. The characterisation data proved that the CuAC has been successfully synthesised with 0.33% Cu(II) loaded onto AC and its surface area increased from 8.37 m2/g to 384.82 m2/g. The dye removal study was conducted at 10 ppm concentration of dye. Result revealed that 0.2 g of CuAC at pH 2 in 90 min removed 100% of CR dye.

An x-ray microprobe based upon a close-coupled focal-spot / glass capillary arrangement

1992 ◽  
Vol 50 (2) ◽  
pp. 1758-1759
Author(s):  
D. A. Carpenter ◽  
M. A. Taylor
Keyword(s):  
Imaging Techniques ◽  
Fluorescence Analysis ◽  
High Sensitivity ◽  
Specimen Preparation ◽  
X Rays ◽  
Glass Capillary ◽  
Close Coupling ◽  
X Ray ◽  
Point To Point ◽  
Beam Damage

The development of intense sources of x rays has led to renewed interest in the use of microbeams of x rays in x-ray fluorescence analysis. Sparks pointed out that the use of x rays as a probe offered the advantages of high sensitivity, low detection limits, low beam damage, and large penetration depths with minimal specimen preparation or perturbation. In addition, the option of air operation provided special advantages for examination of hydrated systems or for nondestructive microanalysis of large specimens.The disadvantages of synchrotron sources prompted the development of laboratory-based instrumentation with various schemes to maximize the beam flux while maintaining small point-to-point resolution. Nichols and Ryon developed a microprobe using a rotating anode source and a modified microdiffractometer. Cross and Wherry showed that by close-coupling the x-ray source, specimen, and detector, good intensities could be obtained for beam sizes between 30 and 100μm. More importantly, both groups combined specimen scanning with modern imaging techniques for rapid element mapping.

XRMF applications of a monolithic, polycapillary, focusing x-ray optic

1996 ◽  
Vol 54 ◽  
pp. 240-241
Author(s):  
D. A. Carpenter ◽  
Ning Gao ◽  
G. J. Havrilla
Keyword(s):  
Trace Elements ◽  
Point Source ◽  
Focal Spot ◽  
Fluorescence Analysis ◽  
X Rays ◽  
Focal Distance ◽  
Spot Diameter ◽  
X Ray ◽  
Focal Spot Diameter

A monolithic, polycapillary, x-ray optic was adapted to a laboratory-based x-ray microprobe to evaluate the potential of the optic for x-ray micro fluorescence analysis. The polycapillary was capable of collecting x-rays over a 6 degree angle from a point source and focusing them to a spot approximately 40 µm diameter. The high intensities expected from this capillary should be useful for determining and mapping minor to trace elements in materials. Fig. 1 shows a sketch of the capillary with important dimensions.The microprobe had previously been used with straight and with tapered monocapillaries. Alignment of the monocapillaries with the focal spot was accomplished by electromagnetically scanning the focal spot over the beveled anode. With the polycapillary it was also necessary to manually adjust the distance between the focal spot and the polycapillary.The focal distance and focal spot diameter of the polycapillary were determined from a series of edge scans.

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