Characterization of Spent Catalysts during Hydrodemetallization of Atmosphere Residue

2011 ◽  
Vol 236-238 ◽  
pp. 538-542
Author(s):  
Yong Jun Liu

The deactivation behavior of industrial hydrodemetallization catalysts was investigated in the presented work. The main objective of the study is to contribute to a better understanding of the nature of the coke and metal deposition on the used catalysts by applying chemical analysis and various advanced analytical techniques, such as X-ray diffraction analysis (XRD), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM), and solid-state carbon-13 nuclear magnetic resonance spectroscopy (13C NMR). The results are discussed scientifically based on the physico–chemical properties of origin and used catalysts.

Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


2014 ◽  
Vol 979 ◽  
pp. 440-443
Author(s):  
W. Siriprom ◽  
K. Teanchai ◽  
S. Kongsriprapan ◽  
J. Kaewkhao ◽  
N. Sangwaranatee

The chemical and physical properties of topsoil and subsoil which collected from the cassava cropping area in Chonburi Province have been investigated. The characterization of both soil sample were used X-Ray Diffraction (XRD), Energy Dispersive X-Ray Fluorescence (EDXRF) while FTIR used to confirmed the formation of intermolecular bonding and Thermo-Gravimetric Analysis (TGA) used for investigated the crystalline. It was found that, the XRD pattern indicated quartz phase. The chemical composition by XRF reported that the soils samples consist of Si, Al, Ca, Fe, K, Mn, Ti, Cr, Zn, Ag and Cu. and TGA results, noticed that the removal of moisture and organics material.


2010 ◽  
Vol 5 (4) ◽  
pp. 1934578X1000500 ◽  
Author(s):  
Naresh D Sanandiya ◽  
Kamalesh Prasad ◽  
Ramavatar Meena ◽  
Arup K Siddhanta

Cellulose was extracted from the roots, stems and stem tips of Salicornia brachiata Roxb. Each crude cellulose sample obtained was fractionated into α- and β-celluloses. The yields of crude cellulose from the stems and stem tips were greatest and lowest, respectively, while the yields of α- and β-celluloses were in the order, roots > stems > stem tips. The cellulose samples were characterized by Fourier transform infrared spectroscopy (FTIR), solid state cross polarisation magic angle spinning carbon-13 nuclear magnetic resonance spectroscopy (CP/MAS 13C NMR), X-ray diffraction pattern (XRD), thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM). The data were compared with those of the celluloses (predominantly α-cellulose) isolated from Whatman filter paper No. 4 (WFP).


2017 ◽  
Vol 0 (0) ◽  
Author(s):  
T. M. Morsi ◽  
Ahmed M. Elbarbary ◽  
Mohamed M. Ghobashy ◽  
Sameh H. Othman

AbstractA nanoparticles chelating solution was synthesized by copolymerization of acrylonitrile (AN) and methacrylic acid (MAA) by radiation induced polymerization technique using 17 kGy irradiation doses. A high copolymer yield was obtained by using 80/20% of AN/MAA and comonomer concentration of 50% (w/w) at a dose rate of 2.58 KGy/h. The resultant cyano group (–CN) of nano-poly(AN/MAA) was converted by chemical modification using hydroxylamine (NH2–OH) to an amidoxime group [–C(=NOH)NH2], which was then confirmed by Fourier transform infrared spectroscopy (FTIR). The physico-chemical properties of poly(AN/MAA) and amidoximated poly(AN/MAA) nanoparticles were studied by FTIR, transmission electron microscopy (TEM), dynamic light scattering (DLS) and thermal gravimetric analysis (TGA). The morphological analysis by TEM and DLS showed a spherical and uniform size of the amidoximated poly(AN/MAA) nanoparticles. TGA results indicated that the thermal stability of poly(AN/MAA) increased by the amidoximation process. The surface decontamination due to uranium was also investigated by the prepared chelating nanoparticles solution. A high purity germanium detector (HPGe) was used as a surface contamination detection tool. The results showed the presence of peaks at different energies, namely, 186.2 keV for Ra-226 (U-238) and 143.76 keV, 163.35 keV and 205.31 for U-235 before the decontamination process. The disappearance of these peaks after decontamination confirmed the applicability and efficiency of the nanoparticles solution in uranium surface decontamination.


2011 ◽  
Vol 55-57 ◽  
pp. 1506-1510 ◽  
Author(s):  
Jing Wei ◽  
Xin Tan ◽  
Tao Yu ◽  
Lin Zhao

A series of Y/TiO2nanoparticles (NPs) were synthesized via sol-gel method. The crystal structures, morphologies and chemical properties were characterized using X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). We investigated the effects of different doping amounts of Y on the reaction of CO2photoreduction. The results shown that 0.1 wt.%Y/TiO2(0.1YT) performed the highest photocatalytic activity, which yielded 384.62 µmol/g∙cat. formaldehyde after 6 h of UV illumination.


2016 ◽  
Vol 8 (2) ◽  
Author(s):  
Reza Mahjub ◽  
Robabeh Allahyar ◽  
Morteza Rafiee-Tehrani ◽  
Farid Abedin Dorkoosh

AbstractCyclosporine is considered a highly lypophilic compound meaning low bioavailability through oral administration. In this study, cyclosporine was entrapped in a novel aromatic, quaternized derivative of chitosan (i.e. methylated N-(4-N,N-dimethyl aminobenzyl) chitosan) in order to improve solubility and bioavailability. Methylated N-(4,N,N-dimethyl aminobenzyl) chitosan was synthesized by the Schiff base reaction method. Polymeric nanoparticles containing cyclosporine was prepared and the physico-chemical properties of prepared nanoparticles were determined. The nanoparticles were studied morphologically using transmission electron microscopy (TEM). Finally, the release of cyclosporine from nanoparticles was studied in vitro using simulated intestinal fluid adjusted to pH of 6.8. For the preparation of nanoparticles, different formulations were studied and it was found that proper nanoparticles were prepared in equal concentration (1 mg/mL) of polymer and sodium tri-poly phosphate (TPP). The size, zeta potential, PdI, EE% and LE% of the prepared nanoparticles were reported as 173±36 nm, 23.1±4.18 mV, 0.243±0.05, 97.1±4.38% and 3.2±0.21%, respectively. The TEM images of nanoparticles revealed spherical to sub-spherical nanoparticles with no sign of agglomeration. This study suggests that preparations of nanoparticles composed of methylated N-(4,N,N-dimethyl aminobenzyl) chitosan can be a good candidate for improving the oral bioavailability of cyclosporine.


2021 ◽  
Author(s):  
Taher Ghrib ◽  
Athaa Al-Otaibi ◽  
Qasim Mahmoud ◽  
Filiz Ercan ◽  
Asghar Ali ◽  
...  

Abstract In this work, it was highlighted synthesis strategy and fundamental characterization of the pure and Ce doped Ba2TiMoO6 with different Ce concentrations were presented. It was investigated its thermal stability by using the Thermal Gravimetric Analysis and Differential Thermal Analysis. The crystal structures and the purity of the compounds were analyzed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The Surface morphology was examined by using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and surface area analysis. The optical properties were examined by using the UV-Vis diffuse reflectance and photoluminescence (PL) spectroscopies. The prepared Ba2TiMoO6 nanopowders are characterized by band gap of 3.41~3.6 eV and violet emission of 426.67 nm wavelength. The degradation efficiency was found approximately 16% of Methyl Blue (MO) after 120 min duration. Our results will predicate new Perovskites materials, which can be used for future environmental applications.


Heritage ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 3908-3918
Author(s):  
Pagona-Noni Maravelaki ◽  
Antonis Theologitis ◽  
Meral Budak Unaler ◽  
Chrysi Kapridaki ◽  
Kali Kapetanaki ◽  
...  

This work characterizes ancient mortars used in construction of the Bronze Age Minoan port at Kommos in Crete. The port dates from c. 1850 BCE with port facilities at the harbor and residences on the Central hillside and the Hilltop. A Greek, Phoenician, and Roman sanctuary overlies the administrative center. The first step collected representative samples from the different construction phases, previous conservation interventions, exposure to different environmental factors, and different material composition. From these 10 mortar samples were analyzed using stereo- and digital microscopy, X-ray diffraction (XRD), X-ray Fluorescence (XRF), and Fourier Transform Infrared spectroscopy (FTIR) to determine texture, morphology, mineralogical, and physico-chemical properties. The physico-chemical and mineralogical analyses divided the samples into two groups: lime binder mortars and earthen binder mortars. The main minerals identified in the samples are calcite, quartz, dolomite, illite, albite, kaolinite, and vermiculite. Analysis of local clay showed that local materials were used in the production of these mortars. The analysis of mortar samples with stereomicroscopy, XRF, and FTIR showed that the samples are mainly composed of calcite and silicates in major quantities along with aluminum, magnesium, and iron oxide in minor quantities. A wide variety of local aggregates and ceramic fragments were used in the production of these ancient mortars. The mortar condition resulted in a decay state that needs conservation interventions. This characterization of the ancient mortars was important for the design of compatible restoration mortars.


2013 ◽  
Vol 680 ◽  
pp. 49-53
Author(s):  
Chang Yu ◽  
Xu Zhang ◽  
Kan He ◽  
Yue Liu ◽  
Jie Shan Qiu

A novel biocompatible Fe2+-chitosan (CTS)/citric acid modified carbon nanotube (CA-CNTs) composite (Fe2+-CTS/CA-CNTs) has been successfully synthesized by covalent bonding and crosslinking chemistry, followed by the reduction. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-Vis spectrum, X-ray diffraction (XRD), inductively coupled plasma (ICP), thermal gravimetric analysis (TGA), and vibrating sample magnetometer (VSM) techniques. The results show that the CTS has been successfully grafted to the CA-CNTs carrier and Fe2+ ions are absorbed on the CTS by coordination bond mode. It was found that the Fe2+-CTS/CA-CNTs composite shows good magnetic properties with a low ratio of remanence to saturation magnetization and is in a superparamagnetic state at room temperature. It is believed that the Fe2+-CTS/CA-CNTs composite will be potential for application in MRI.


2016 ◽  
Vol 1133 ◽  
pp. 501-504 ◽  
Author(s):  
Muhammad Zulfiqar ◽  
Abdul Aziz Omar ◽  
Sujan Chowdhury

In this paper, TiO2 nanotubes (TNTs) were synthesized through simple chemical hydrothermal treatment process when anatase TiO2 nanopowder is chemically treated with 10 M NaOH and >99.5% ethanol at 180°C for 24 hr. According to the transmission electron microscopic (TEM) image analysis TNTs tubes were formed in the length sizes from 400 to 700 nm with inner diameter of 5 nm and outer diameter of 8 nm. The morphological and structural properties of synthesized TNTs was characterized by powder X-ray diffraction (XRD), thermal gravimetric analysis (TGA), UV–Vis diffuse reflectance spectra (DRS).


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