scholarly journals INFLUENCE OF GAS-PHASE REDUCTION DURATION ON THE COMPOSITION OF POLYMER-STABILIZED CATALYTIC SYSTEMS OF LIQUID-PHASE HYDROGENATION OF BENZENE

Author(s):  
Алексей Владимирович Быков ◽  
Галина Николаевна Демиденко ◽  
Линда Жанновна Никошвили

В работе исследовано влияние продолжительности восстановления металлосодержащих полимерстабилизированных систем Ме/MN100 на их активность в процессе жидкофазного гидрирования бензола. Каталитические системы охарактеризованы методами инфракрасной спектроскопии диффузного отражения и рентгенофотоэлектронной спектроскопии. В ходе исследования показано, что продолжительность восстановления в токе водорода при 300С влияет на активность изученных систем и состав их поверхности. The effect of the reduction duration of metal-containing polymer-stabilized Me/MN100 systems on their activity in the process of liquid-phase hydrogenation of benzene is studied. Catalytic systems are characterized by diffuse reflection infrared spectroscopy and x-ray photoelectron spectroscopy. The study shows that the duration of reduction in the hydrogen flow at 300C affects the activity of the studied systems and the composition of their surface.

2019 ◽  
Vol 5 (11) ◽  
pp. 26-36
Author(s):  
A. Bykov ◽  
G. Demidenko

The study is aimed at creating a polymer-stabilized ruthenium-containing catalytic system for liquid-phase hydrogenation of arenes in alkanes, including the creation of catalytic systems for upgrading the fuels of internal combustion engines. As a catalyst system, a catalyst based on ruthenium compounds stabilized in an industrial hypercrosslinced polystyrene MN100 has been proposed. Dodecane was selected as a model reaction solvent. During the study, the effect of temperature and pressure of hydrogen on the speed and differential selectivity of the hydrogenation of benzene and toluene in their mixture in dodecane was studied. It was shown that the differential selectivity of hydrogenation with respect to benzene increases with temperature up to 160°C and decreases with an increase in the total pressure in the reaction mixture. A study of the nature of the active phase of the catalytic system by X-ray photoelectron spectroscopy showed that ruthenium (IV) oxide is formed during the reduction of the catalyst.


2011 ◽  
Vol 383-390 ◽  
pp. 3188-3191
Author(s):  
Han Jie Huang ◽  
Wen Long She ◽  
Ling Wen Yang ◽  
Hai Peng Huang

A visible-light-responsive TiO2-xNx photocatalyst was prepared by a very simple method. Ammonia solution was used as nitrogen resource in this paper. The TiO2-xNx photocatalyst was characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), UV-Vis diffuse reflection spectra (DRS), and X-ray photoelectron spectroscopy (XPS). The ethylene was selected as a target pollutant under visible light excitation to evaluate the activity of this photocatalyst. The new prepared TiO2-xNx photocatalyst with strong photocatalytic activity under visible light irradiation was demonstrated in the experiment.


1990 ◽  
Vol 93 (9) ◽  
pp. 6357-6362 ◽  
Author(s):  
M. P. Keane ◽  
S. Svensson ◽  
A. Naves de Brito ◽  
N. Correia ◽  
S. Lunell ◽  
...  

Catalysts ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 11 ◽  
Author(s):  
Shahram Alijani ◽  
Sofia Capelli ◽  
Stefano Cattaneo ◽  
Marco Schiavoni ◽  
Claudio Evangelisti ◽  
...  

The catalytic performance of a series of 1 wt % Pd/C catalysts prepared by the sol-immobilization method has been studied in the liquid-phase hydrogenation of furfural. The temperature range studied was 25–75 °C, keeping the H2 pressure constant at 5 bar. The effect of the catalyst preparation using different capping agents containing oxygen or nitrogen groups was assessed. Polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and poly (diallyldimethylammonium chloride) (PDDA) were chosen. The catalysts were characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The characterization data suggest that the different capping agents affected the initial activity of the catalysts by adjusting the available Pd surface sites, without producing a significant change in the Pd particle size. The different activity of the three catalysts followed the trend: PdPVA/C > PdPDDA/C > PdPVP/C. In terms of selectivity to furfuryl alcohol, the opposite trend has been observed: PdPVP/C > PdPDDA/C > PdPVA/C. The different reactivity has been ascribed to the different shielding effect of the three ligands used; they influence the adsorption of the reactant on Pd active sites.


2019 ◽  
Vol 80 (6) ◽  
pp. 1076-1084 ◽  
Author(s):  
Hualin Chen ◽  
Huajun Xie ◽  
Jiangmin Zhou ◽  
Yueliang Tao ◽  
Yongpu Zhang ◽  
...  

Abstract In this study, starch-stabilized nanoscale zero-valent iron (S-nZVI) was produced using the liquid-phase reduction method. It was used to remove chromium from wastewater, and compared to a commercial nanoscale zero-valent iron (C-nZVI). Both nZVIs were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The characterization results showed that S-nZVI had smaller particles and a more uniform particle size distribution than C-nZVI. Both nZVIs showed a core-shell structure with the Fe0 core prominently surrounded by less iron oxides of Fe2+ and Fe3+. The optimal application methods to remove Cr(VI) from wastewater were also explored. The results showed that both the removal efficiencies of total Cr and Cr(VI) increased with increases in the addition of nZVIs, while the removal efficiencies of total Cr and Cr(VI) by S-nZVI were clearly higher than that of C-nZVI, especially in a low pH range (pH = 1.0–6.0). This research indicated that starch-stabilized nanoscale zero-valent iron is a valuable material to remove heavy metals from wastewater due to its stability and high reactivity.


1977 ◽  
Vol 55 (8) ◽  
pp. 1279-1284 ◽  
Author(s):  
Barry C. Trudell ◽  
S. James W. Price

The gas phase X-ray photoelectron spectra, XPS, were observed for the series C6F5X (X = F, Cl, I, Br, H). Binding energies were determined from the spectra using the ESCAPLOT Program. Charge calculations were carried out using Equalization of Electronegativity, CNDO/2, and ACHARGE approaches on each molecule. The more sophisticated analysis leads to the following equation correlating the (C 1s) binding energies and the atomic charges qi[Formula: see text]


2020 ◽  
Vol 73 (11) ◽  
pp. 1088
Author(s):  
Altafhusen Naikwade ◽  
Megha Jagadale ◽  
Dolly Kale ◽  
Gajanan Rashinkar

A new magnetic nanoparticle supported ionic liquid phase (SILP) catalyst containing perruthenate anions was prepared by a multistep procedure. The various analytical techniques such as FT-IR spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, thermogravimetric analysis, energy dispersive X-ray analysis, and vibrating sample magnetometer analysis ascertained the successful formation of catalyst. The performance of a magnetically retrievable SILP catalyst was evaluated in the selective oxidation of alcohols. The split test and leaching studies of the SILP catalyst confirmed its heterogeneous nature. In addition, the reusability potential of SILP catalyst was also investigated which revealed its robust activity up to six consecutive cycles.


1984 ◽  
Vol 39 (11) ◽  
pp. 1536-1540 ◽  
Author(s):  
Reinhard Schulz ◽  
Armin Schweig

Abstract The gas-phase pyrolysis of cyclohexeno-1,2,3-selenadiazole and cycloocteno-1,2,3-selenadiazole has been investigated by variable temperature photoelectron spectroscopy and matrix IR spectroscopy. The ring contracted, highly reactive products cyclopentylidenselenoketene (cyclopentylidenmethanselone) and cycloheptylidenselenoketene (cycloheptylidenmethanselone) - which had not been found in liquid phase thermolysis experiments - have been detected. Additionally HeI photoelectron and IR spectra of analogous ketenes and thioketenes are presented for comparative reasons.


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