scholarly journals Acetalization of Glycerol with Citral over Heteropolyacids Immobilized on KIT-6

Catalysts ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 81
Author(s):  
José Castanheiro
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Fixed Time ◽  
Tungstophosphoric Acid ◽  
X Ray Diffraction ◽  
Glycerol Conversion ◽  
X Ray ◽  
Inductively Coupled ◽  
Catalytic Stability ◽  
Scanning Electron

Glycerol acetalization with citral was studied using a heteropolyacid (tungstophosphoric acid) supported on KIT-6, as a catalyst, at 100 °C. Different catalysts were synthesized. Catalysts were characterized by scanning electron microscopy (SEM), inductively coupled plasma (ICP), X-ray diffraction (XRD), attenuated total refletion-Fourier transform infrared spectroscopy (ATR-FTIR), and potentiometric titrations. At a fixed time, the glycerol conversion increased with the H3PW12O40 (PW) on KIT-6. PW4-KIT-6 material had a higher conversion than other catalysts. The optimization of glycerol’s acetalization with citral was studied under the PW4-KIT-6 catalyst. After 5 h, it was found that, at T = 100 °C, with m = 0.3 g of solid, molar glycerol:citral = 1:2.25, the conversion of glycerol was 89%. Moreover, the PW4-KTI-6 catalyst showed good catalytic stability.

scholarly journals Efflorescent Sulfate Crystallization on Fractured and Polished Colloform Pyrite Surfaces: A Migration Pathway of Trace Elements

Minerals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 12
Author(s):  
Dimitrina Dimitrova ◽  
Vassilka Mladenova ◽  
Lutz Hecht
Keyword(s):  
Electron Microscopy ◽  
Trace Elements ◽  
Inductively Coupled Plasma ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
X Ray ◽  
Inductively Coupled ◽  
Migration Pathway ◽  
Plasma Mass Spectrometry ◽  
Scanning Electron

The colloform pyrite variety incorporates many trace elements that are released in the environment during rapid oxidation. Colloform pyrite from the Chiprovtsi silver–lead deposit in Bulgaria and its oxidation efflorescent products were studied using X-ray diffractometry, scanning electron microscopy, electron microprobe analysis, and laser ablation inductively coupled plasma mass spectrometry. Pyrite is enriched with (in ppm): Co (0.1–964), Ni (1.8–3858), Cu (2.9–3188), Zn (3.1–77), Ag (1.2–1771), As (8179–52,787), Se (2.7–21.7), Sb (48–17792), Hg (4–2854), Tl (1.7–2336), Pb (13–7072), and Au (0.07–2.77). Gypsum, anhydrite, szomolnokite, halotrichite, römerite, copiapite, aluminocopiapite, magnesiocopiapite, coquimbite, aluminocoquimbite, voltaite, and ammoniomagnesiovoltaite were identified in the efflorescent sulfate assemblage. Sulfate minerals contain not only inherited elements from pyrite (Cr, Fe, Co, Ni, Cu, Zn, Ag, In, As, Sb, Hg, Tl, and Pb), but also newly introduced elements (Na, Mg, Al, Si, P, K, Ca, Sc, Ti, V, Mn, Ga, Rb, Sr, Y, Zr, Sn, Cs, Ba, REE, U, and Th). Voltaite group minerals, copiapite, magnesiocopiapite, and römerite incorporate most of the trace elements, especially the most hazardous As, Sb, Hg, and Tl. Colloform pyrite occurrence in the Chiprovtsi deposit is limited. Its association with marbles would further restrict the oxidation and release of hazardous elements into the environment.

scholarly journals Geochemical characteristics of elements in coal seams 41 and 42 of Heshan Coalfield, South China

2019 ◽  
Vol 38 (1) ◽  
pp. 137-157 ◽  
Author(s):  
Qiaojing Zhao ◽  
Yongjie Niu ◽  
Zhizhong Xie ◽  
Kuangming Zhang ◽  
Jinming Zhou ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Geochemical Characteristics ◽  
X Ray Diffraction ◽  
Coal Seams ◽  
X Ray ◽  
Inductively Coupled ◽  
Reducing Environment ◽  
Conventional Microscopy ◽  
Hydrothermal Activities ◽  
Scanning Electron

Coal seams 41 and 42 of the Heshan Coalfield belong to superhigh-organic-sulfur coals. In order to study the geochemical characteristics of the coals, 15 coal samples and 6 rock samples were collected from both coal seams and the roof/floor rocks. The samples were investigated by using conventional microscopy, inductively coupled plasma mass spectroscopy, X-ray diffraction, X-ray fluorescence, and scanning electron microscopy with an energy-dispersive X-ray spectroscopy. The results show that minerals in the coals are dominated by kaolinite and a mixed layer illite/smectite and illite; small ratios of pyrite, quartz, chlorite, smectite, calcite, and dolomite are also present. Under the microscope, these pyrites occur as framboidal, euhedral, homogeneous, anhedral, nodular, and fine dissemination shapes. In Shicun Mine, the trace elements Li, Y, Zr, Sn, Sm, and Tb are enriched; Zn and Ba are depleted. However, in the Heliluoshan Mine, Mo is significantly enriched; Li, Zr, Cs, and U are enriched; and Co and Ba are depleted. The occurrence of Li and Ga is associated mainly with organic matter and sulfate minerals. U and Mo occur in silicate minerals, carbonate minerals, illite, I/S, and pyrite. A reducing environment is beneficial for the enrichment of V, Cr, Mn, Ni, Mo, Cd, and U. The abundances of sulfur in Heshan were controlled mainly by the degree of seawater influence and hydrothermal activities.

scholarly journals Use of the System S2o3 (2-) -O2 for the Leaching of Precious Metals Contained in a Mineral From Molango in the State of Hidalgo, Mexico

2018 ◽  
Vol 14 (3) ◽  
pp. 48 ◽  
Author(s):  
Edmundo Roldán-Contreras ◽  
Juan Hernández-Ávila ◽  
Eduardo Cerecedo-Sáenz ◽  
Ma. Isabel Reyes-Valderrama ◽  
Eleazar Salinas-Rodríguez
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Energy Dispersive Spectrometry ◽  
Precious Metals ◽  
X Rays ◽  
X Ray ◽  
Plasma Spectrometry ◽  
Inductively Coupled ◽  
Inductively Coupled Plasma Spectrometry ◽  
Scanning Electron

The newer tendencies of research, related with the leaching of precious metals, involves the use of non toxic reagents that allows the leaching of a mineral of sedimentary origin using the system S2 - O3 2- - O2. Prior to thisprocess, the mineral was characterized by Scanning Electron Microscopy (SEM) in conjunction with Energy Dispersive Spectrometry of X – rays (EDS), X- ray mapping. Finally, the chemical composition was executed by Inductively Coupled Plasma Spectrometry (ICP). According to the results obtained, it was possible to determine that the mineral studied has adequate contents of gold, palladium, silver, and platinum. And after the leaching process, it could be possible to leach the gold and palladium that it contains, getting recoveries of 90% and 85 %, respectively. In the case of silver, a redissolution or precipitation could occur during the first minutes of reaction.

The nature and origin of non-marine 10 Å clay from the Late Eocene and Early Oligocene of the Isle of Wight (Hampshire Basin), UK

Clay Minerals ◽  
2001 ◽  
Vol 36 (3) ◽  
pp. 447-464 ◽  
Author(s):  
J. M. Huggett ◽  
A. S. Gale ◽  
N. Clauer
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Late Eocene ◽  
X Ray Diffraction ◽  
Wetting And Drying ◽  
Wet Chemistry ◽  
X Ray ◽  
Inductively Coupled ◽  
Early Oligocene ◽  
Transmission Electron

AbstractVariegated palaeosols, which formed from weathering of clays, silts and brackish to freshwater limestones, are present in the Late Eocene–Early Oligocene Solent Group of the Hampshire Basin, southern UK. The composition and origin of the clay in three segments of the lower part of the Solent Group have been investigated by X-ray diffraction, microprobe analysis, inductively coupled plasma-mas spectrometry, K/Ar dating, high resolution scanning electron microscopy, analytical transmission electron microscopy and wet chemistry. The detrital clay mineral suite is dominated by illite and smectite with minor kaolinite and chlorite. Seasonal wetting and drying in gley soils has resulted in replacement of smectite by Fe-rich, or illite-rich illitesmectite. Illite has also formed with gypsum and calcite in ephemeral hypersaline alkaline lakes that periodically dried out. This illite may have precipitated directly from solution. X-ray diffraction data and probe analyses indicate that the neoformed illite is Fe-rich. The K and Fe for the illitization are thought to be derived from weathered glauconite reworked from the underlying Bracklesham Group and Barton Beds.

scholarly journals Ag nanoparticles immobilized on new mesoporous triazine-based carbon (MTC) as green and recoverable catalyst for reduction of nitroaromatic in aqueous media

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Narges Vahedi-Notash ◽  
Majid M. Heravi ◽  
Ali Alhampour ◽  
Pourya Mohammadi
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Aqueous Media ◽  
Catalytic Efficiency ◽  
Active Species ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inductively Coupled ◽  
Transmission Electron ◽  
Recoverable Catalyst

Abstract In this research, we reported an effective method for the synthesis of a new mesoporous triazine-based carbon (MTC) substrate and its application as the green and recoverable catalyst in the synthesis of organic compounds. The porous carbon acted as a substrate for silver active species after its surface modification by chloroacetonitrile (Ag@MTC). The Ag@MTC nanocatalyst was characterized by several techniques namely, Fourier-transform infrared spectroscopy, field emission scanning electron microscopy with energy dispersive spectroscopy, X-ray diffraction, transmission electron microscopy, Brunauer–Emmett–Teller surface area analysis, and inductively coupled plasma. The Ag@MTC catalyst was applied for the reduction of nitroaromatic compounds in aqueous media by using NaBH4 (reducing agent) at room temperature. This nanocatalyst can be readily recovered and recycled for at least nine runs without a notable decrease in its efficiency. Catalytic efficiency studies exhibited that Ag@MTC nanocatalyst had good activity towards reduction reactions.

Synthesis and Characterization of Fe2+-CTS/CA-CNTs Composite and its Magnetic Properties

2013 ◽  
Vol 680 ◽  
pp. 49-53
Author(s):  
Chang Yu ◽  
Xu Zhang ◽  
Kan He ◽  
Yue Liu ◽  
Jie Shan Qiu
Keyword(s):  
Electron Microscopy ◽  
Magnetic Properties ◽  
Inductively Coupled Plasma ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inductively Coupled ◽  
Transmission Electron ◽  
Superparamagnetic State

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.

Bausch & Lomb-ARL: Where We Come From, Who We are

1981 ◽  
Vol 35 (2) ◽  
pp. 226-235 ◽  
Author(s):  
Robert L. Eklund
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Applied Research ◽  
Optical Emission ◽  
X Ray ◽  
Inductively Coupled ◽  
Scanning Electron ◽  
Alex Haley

Remembering where we came from, points out author Alex Haley in Roots, helps us know who we are today. The roots of spectroscopy are closely intertwined with those of Bausch & Lomb-ARL, known to the industry for more than 45 years as Applied Research Laboratories. A member of Bausch & Lomb's Instrument Group, ARL today is a major multinational supplier of spectrochemical instruments in the optical emission, inductively coupled plasma (ICP), X-ray fluorescence and diffraction, microanalysis, and scanning electron microscopy fields. Its story begins with a graduate student's dream—which, unlike most dreams, came true.

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