scholarly journals Alumina Coated Silica Nanosprings (NS) Support Based Cobalt Catalysts for Liquid Hydrocarbon Fuel Production From Syngas

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1810
Author(s):  
Abdulbaset Alayat ◽  
Elena Echeverria ◽  
Farid Sotoudehniakarani ◽  
David N. Mcllroy ◽  
Armando G. McDonald
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Fixed Bed ◽  
Chemical Properties ◽  
Hydrocarbon Fuel ◽  
Liquid Hydrocarbon ◽  
Cobalt Catalysts ◽  
Impregnation Method ◽  
X Ray ◽  
Co Conversion

The effects of Al2O3 coating on the performance of silica nanospring (NS) supported Co catalysts for Fischer–Tropsch synthesis (FTS) were evaluated in a quartz fixed-bed microreactor. The Co/NS-Al2O3 catalysts were synthesized by coating the Co/NS and NS with Al2O3 by an alkoxide-based sol-gel method (NS-Al-A and NS-Al-B, respectively) and then by decorating them with Co. Co deposition was via an impregnation method. Catalysts were characterized before the FTS reaction by the Brunauer–Emmett–Teller (BET) method, X-ray diffraction, transmission electron microscopy, temperature programmed reduction, X-ray photoelectron spectroscopy, differential thermal analysis and thermogravimetric analysis in order to find correlations between physico-chemical properties of catalysts and catalytic performance. The products of the FTS were trapped and analyzed by GC-TCD and GC-MS to determine the CO conversion and reaction selectivity. The Al2O3 coated NS catalyst had a significant affect in FTS activity and selectivity in both Co/NS-Al2O3 catalysts. A high CO conversion (82.4%) and Σ > C6 (86.3%) yield were obtained on the Co/NS-Al-B catalyst, whereas the CO conversion was 62.8% and Σ > C6 was 58.5% on the Co/NS-Al-A catalyst under the same FTS experimental condition. The Co/NS-Al-A catalyst yielded the aromatic selectivity of 10.2% and oxygenated compounds.

scholarly journals Influence of Mesoporous Inorganic Al–B–P Amphiprotic Surfactant Material Resistances of Wood against Brown and White-Rot Fungi (Part 1)

Coatings ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 108
Author(s):  
Kouomo Guelifack Yves Beaudelaire ◽  
Biaorong Zhuang ◽  
John Tosin Aladejana ◽  
Dehong Li ◽  
Xinjun Hou ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Chemical Properties ◽  
White Rot Fungi ◽  
Untreated Wood ◽  
White Rot ◽  
Modulus Of Rupture ◽  
X Ray ◽  
Mass Losses ◽  
Surfactant Material

This study describes the application of aluminum sulfate Al2(SO4)3, boric acid H3BO3, phosphoric acid H3PO4 (Al–B–P) and amphiprotic surfactant material synthesis by the sol-gel process, which were adopted as novel precursors for wood modification. The efficacy of Al–B–P-treated wood was tested against Poria placenta and Coriolus versicolor. Untreated wood samples had higher mass losses (>40%) compared to the treated sample, which had the lowest wood mass losses (of 4%) against P. placenta and C. versicolor. To analyze the reaction mechanism of Al–B–P wood, the mechanical properties, chemical structure, crystallinity, thermal analysis, binding energy and wettability was examined by modulus of rupture (MOR), modulus of elasticity (MOE), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), Thermogravimetric analysis (TG) and X-ray photoelectron spectroscopy (XPS), respectively. Scanning electron microscopy- energy-dispersive X-ray spectroscopy (SEM-EDS) confirmed the wood colonization by fungi, and was used to identify the microstructures and morphologies changes that occurred in the cells during degradation by white and brown-rot fungi. At the same time, X-ray photoelectron spectroscopy (XPS) was employed to analyze the physical and chemical properties of the samples. Therefore, the study confirmed that Al–B–P and amphiprotic surfactant could replace the traditional wood preservative products, and have the potential to extend the service life of wood, particularly in soil contact and outdoor usage.

Photoconversion of CO2 using copper-modified titanium dioxide nanoparticles

2011 ◽  
Vol 76 (11) ◽  
pp. 1335-1346 ◽  
Author(s):  
Jing Wei ◽  
Xin Tan ◽  
Tao Yu ◽  
Lin Zhao
Keyword(s):  
Titanium Dioxide ◽  
Photoelectron Spectroscopy ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Chemical Properties ◽  
High Photocatalytic Activity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Illumination ◽  
One Step

A series of copper-modified titanium dioxide (Cu/TiO2) nanoparticles were synthesized via one-step sol-gel method. The crystal structure and chemical properties were characterized using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The Cu/TiO2nanoparticles were applied to CO2photoconversion and the yield of formaldehyde was used to evaluate the photocatalytic performance. The optimum amount of copper modifying was 0.6 wt.% and the yield of formaldehyde was 946 μmol/gcatunder UV illumination for 6 h. 20 wt.% Cu/TiO2also performed a high photocatalytic activity, which yielded 433 μmol/gcatformaldehyde under UV illumination for 6 h.

Synthesis of CeO2 Supported BaCoO3 Perovskites for Chemical-Looping Methane Reforming to Syngas and Hydrogen

2017 ◽  
Author(s):  
Haoran Ding ◽  
Yongqing Xu ◽  
Linyi Xiang ◽  
Qiyao Wang ◽  
Cheng Shen ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Fixed Bed ◽  
Gas Production ◽  
Fixed Bed Reactor ◽  
Methane Reforming ◽  
Chemical Looping ◽  
X Ray ◽  
Syngas Production ◽  
Fuel Reactor

In order to reduce the hotspots in partial oxidation of methane, CeO2 supported BaCoO3 perogvskite-type oxides were synthesized using a sol-gel method and applied in chemical-looping steam methane reforming (CL-SMR). The synthesized BaCoO3-CeO2 was characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). XRD and XPS results suggested that the obtained BaCoO3 was pure crystalline perovskite, its crystalline structure and lattice oxygen could regenerate after calcining. The reactivity of perovskite-type oxides in CL-SMR was evaluated using a fixed-bed reactor. Gas production rates and H2/CO ratios showed that the optimal reaction temperature was about 860 °C and the properly reaction time in fuel reactor was about 180s when Weight Hourly Space Velocity (WHSV) was 23.57 h−1. The syngas production in fuel reactor were 265.11 ml/g, hydrogen production in reforming reactor were 82.53 ml/g. (CSPE)

scholarly journals Sulfur resistance of Ce-Mn/TiO 2 catalysts for low-temperature NH 3 –SCR

2018 ◽  
Vol 5 (3) ◽  
pp. 171846 ◽  
Author(s):  
Quan Xu ◽  
Wenjing Yang ◽  
Shitong Cui ◽  
Jason Street ◽  
Yan Luo
Keyword(s):  
Low Temperature ◽  
Photoelectron Spectroscopy ◽  
Conversion Rate ◽  
Active Sites ◽  
Sol Gel ◽  
Textural Properties ◽  
Catalyst Loading ◽  
Impregnation Method ◽  
No Conversion ◽  
X Ray

Ce-Mn/TiO 2 catalyst prepared using a simple impregnation method demonstrated a better low-temperature selective catalytic reduction of NO with NH 3 (NH 3 –SCR) activity in comparison with the sol-gel method. The Ce-Mn/TiO 2 catalyst loading with 20% Ce had the best low-temperature activity and achieved a NO conversion rate higher than 90% at 140–260°C with a 99.7% NO conversion rate at 180°C. The Ce-Mn/TiO 2 catalyst only had a 6% NO conversion rate decrease after 100 ppm of SO 2 was added to the stream. When SO 2 was removed from the stream, the catalyst was able to recover completely. The crystal structure, morphology, textural properties and valence state of the metals involving the novel catalysts were investigated using X-ray diffraction, N 2 adsorption and desorption analysis, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive spectroscopy, respectively. The decrease of NH 3 –SCR performance in the presence of 100 ppm SO 2 was due to the decrease of the surface area, change of the pore structure, the decrease of Ce 4+ and Mn 4+ concentration and the formation of the sulfur phase chemicals which blocked the active sites and changed the valence status of the elements.

Characterization of Y/TiO2 Nanoparticles and their Reactivity for CO2 Photoreduction

2011 ◽  
Vol 55-57 ◽  
pp. 1506-1510 ◽  
Author(s):  
Jing Wei ◽  
Xin Tan ◽  
Tao Yu ◽  
Lin Zhao
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Illumination ◽  
Transmission Electron ◽  
And Chemical Properties

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.

scholarly journals High Selectivity and Stability of Nickel Catalysts for CO2 Methanation: Support Effects

Catalysts ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 24 ◽  
Author(s):  
Jeremías Martínez ◽  
Edgar Hernández ◽  
Salvador Alfaro ◽  
Ricardo López Medina ◽  
Guadalupe Valverde Aguilar ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Fixed Bed ◽  
Tetragonal Zirconia ◽  
Nickel Catalysts ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
Methane Formation ◽  
Co2 Methanation ◽  
X Ray

In this work, we present an investigation concerning the evaluation of the catalytic properties of Ni nanoparticles supported on ZrO2, SiO2, and MgAl2O4 for CO2 hydrogenation to methane. The supports were prepared by coprecipitation and sol-gel, while Ni was incorporated by impregnation (10–20 wt %). X-ray diffraction, nitrogen physisorption, temperature-programmed reduction, H2 pulse chemisorption, Raman spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy were the main characterization techniques employed. A laboratory fixed-bed reactor operated at atmospheric pressure, a temperature range of 350–500 °C, and a stoichiometric H2/CO2 molar ratio was used for catalyst evaluation. The most outstanding results were obtained with nickel catalysts supported on ZrO2 with CO2 conversions of close to 60%, and selectivity to methane formation was 100% on a dry basis, with high stability after 250 h of reaction time. The majority presence of tetragonal zirconia, as well as the strong Ni–ZrO2 interaction, were responsible for the high catalytic performance of the Ni/ZrO2 catalysts.

Development of quasi-two-dimensional Nb2O5 nanoflakes with thickness-depended electro-chemical properties

2015 ◽  
Vol 08 (01) ◽  
pp. 1550007 ◽  
Author(s):  
Serge Zhuiykov ◽  
Eugene Kats ◽  
Tomoaki Sato ◽  
Hiroshi Ikeda ◽  
Norio Miura
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Chemical Properties ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Conductive Atomic Force Microscopy ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Structural Surface

Quasi-two-dimensional (Q2D) Nb 2 O 5 nanoflakes were synthesized by combined sol–gel/exfoliation method with the average thickness of 10–25 nm. Their structural, surface- and electro-chemical properties were closely studied and analyzed by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), conductive atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy techniques.

scholarly journals Effect of Ce Addition on Adsorption and Oxidation of NO over MnO x /Al2O3

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Chunhui Mou ◽  
Hui Li ◽  
Ning Dong ◽  
Shien Hui ◽  
Denghui Wang
Keyword(s):  
Catalytic Activity ◽  
Catalytic Oxidation ◽  
Photoelectron Spectroscopy ◽  
Active Sites ◽  
Catalyst Surface ◽  
Fixed Bed ◽  
No Oxidation ◽  
Impregnation Method ◽  
X Ray ◽  
Oxidation Of No

The MnO x /Al2O3 catalysts with different Ce content doping were prepared by an ultrasonic impregnation method, and the catalytic activity for NO oxidation removal was tested in a fixed-bed quartz tube furnace. Simultaneously, the catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), full-automatic physical-chemical adsorption instrument, and field emission scanning electron microscope (FESEM) to analyze the effect of Ce addition on the adsorption capacity and catalytic activity. Experimental results validated that the activity of the MnO x /Al2O3 catalyst was greatly promoted with Ce addition. According to the characterization results, it could be concluded that Ce doping led to significant changes in the crystalline phase on the catalyst surface, which increased the relative content of surface lattice oxygen and promoted the catalytic oxidation of NO. By observing the physical properties of the surface and analyzing the surface elements of the catalyst, it could be inferred that a manganese-cerium solid solution was formed on the surface of Mn0.4Ce0.05/Al. Moreover, Ce addition increased the catalyst pore size, which enhanced the adsorption and contact of NO and O2 with the active sites on the catalyst surface, and reduced the resistance of the reactants during internal diffusion. All these variations assigned to Mn0.4Ce0.05/Al were favorable for the catalytic oxidation of NO.

Effects of Calcination Temperature on Photoreduction Activity of Cu/TiO2 Nanoparticles

2011 ◽  
Vol 55-57 ◽  
pp. 1648-1652
Author(s):  
Jing Wei ◽  
Xin Tan ◽  
Tao Yu ◽  
Lin Zhao
Keyword(s):  
Calcination Temperature ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Chemical Properties ◽  
Titania Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
One Step ◽  
Doped Titania

A one step sol-gel method was used for preparation of Cu doped titania nanoparticles (NPs). The crystal structures, morphologies and chemical properties were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). We discussed the calcination temperature effection on the photoreduction activity of Cu/TiO2. When the calcination temperature was 500°C, the synthesized Cu/TiO2 performed the highest photocatalytic activity.

scholarly journals Effect of Operating Temperature, Pressure and Potassium Loading on the Performance of Silica-Supported Cobalt Catalyst in CO2 Hydrogenation to Hydrocarbon Fuel

Catalysts ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 807 ◽  
Author(s):  
Iloy ◽  
Jalama
Keyword(s):  
Photoelectron Spectroscopy ◽  
Operating Temperature ◽  
Fixed Bed ◽  
Co2 Hydrogenation ◽  
Fixed Bed Reactor ◽  
Activation Process ◽  
Operating Pressure ◽  
Impregnation Method ◽  
X Ray ◽  
Temperature Programmed

Potassium (1–5 wt.%)-promoted and unpromoted Co/SiO2 catalysts were prepared by impregnation method and characterized by nitrogen physisorption, temperature-programmed reduction (TPR), CO2 temperature-programmed desorption (TPD), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques. They were evaluated for CO2 hydrogenation in a fixed bed reactor from 180 to 300 °C within a pressure range of 1–20 bar. The yield for hydrocarbon products other than methane (C2+) was found to increase with an increase in the operating temperature and went through a maximum of approximately 270 °C. It did not show any significant dependency on the operating pressure and decreased at potassium loadings beyond 1 wt.%. Potassium was found to enhance the catalyst ability to adsorb CO2, but limited the reduction of cobalt species during the activation process. The improved CO2 adsorption resulted in a decrease in surface H/C ratio, the latter of which enhanced the formation of C2+ hydrocarbons. The highest C2+ yield was obtained on the catalyst promoted with 1 wt.% of potassium and operated at an optimal temperature of 270 °C and a pressure of 1 bar.

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