scholarly journals Ni Catalysts Based on Attapulgite for Hydrogen Production through the Glycerol Steam Reforming Reaction

Catalysts ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 650 ◽  
Author(s):  
Nikolaos D. Charisiou ◽  
Victor Sebastian ◽  
Steven J. Hinder ◽  
Mark A. Baker ◽  
Kyriaki Polychronopoulou ◽  
...  
Keyword(s):  
Steam Reforming ◽  
Carbon Deposition ◽  
Active Phase ◽  
Catalytic Performance ◽  
Ni Catalysts ◽  
Gaseous Products ◽  
Filamentous Carbon ◽  
Catalytic Material ◽  
Spent Catalysts ◽  
The Stability

Attapulgite (ATP, a natural clay) was used as carrier to produce a nickel-based catalyst (Ni/ATP) for the work that is presented herein. Its catalytic performance was comparatively assessed with a standard Ni/Al2O3 sample for the glycerol steam reforming (GSR) reaction. It was shown that the ATP support led to lower mean Ni crystallite size, i.e., it increased the dispersion of the active phase, to the easier reduction of NiO and also increased the basicity of the catalytic material. It was also shown that it had a significant effect on the distribution of the gaseous products. Specifically, for the Ni/ATP catalyst, the production of liquid effluents was minimal and subsequently, conversion of glycerol into gaseous products was higher. Importantly, the Ni/ATP favored the conversion into H2 and CO2 to the detriment of CO and CH4. The stability experiments, which were undertaken at a low WGFR, showed that the activity of both catalysts was affected with time as a result of carbon deposition and/or metal particle sintering. An examination of the spent catalysts revealed that the coke deposits consisted of filamentous carbon, a type that is known to encapsulate the active phase with fatal consequences.

scholarly journals The Effect of Tourmaline on SCR Denitrification Activity of MnOx/TiO2 at Low Temperature

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1020
Author(s):  
Yizhe Helian ◽  
Suping Cui ◽  
Xiaoyu Ma
Keyword(s):  
Low Temperature ◽  
Catalytic Reduction ◽  
Catalytic Performance ◽  
Scr Catalyst ◽  
Highly Efficient ◽  
Nh3 Scr ◽  
Catalytic Material ◽  
Acidic Sites ◽  
Denitrification Activity ◽  
The Stability

Selective catalytic reduction (SCR) technology is the most widely used flue gas denitration technology at present. The stability of a catalyst is the main factor limiting the development of this technology. In this study, an environmentally friendly and highly efficient NH3-SCR catalyst was prepared by coprecipitation method from acidolysis residue of industrial waste and tourmaline. We found that the addition of tourmaline has an important impact on the denitration activity of the catalytic material. The NOx conversion exceeded 97% at 200 °C with the dosage of 10% tourmaline, which is about 7% higher than that without doping. The improvement of catalytic performance was mostly attributed to the permanent electrodes of tourmaline, which effectively promotes the dispersion of MnOx/TiO2 catalytic materials, increases the number of acidic sites and changes the valence distribution of manganese ions in products, which speeds up the diffusion of protons and ions, resulting in the acceleration of redox reaction. These as-developed tourmaline-modified MnOx/TiO2 materials have been demonstrated to be promising as a new type of highly efficient low-temperature NH3-SCR catalyst.

Study on the Cu-Ni/Y2O3-ZrO2 Catalytic Performance in Ethanol Steam Reforming

2012 ◽  
Vol 512-515 ◽  
pp. 2257-2261 ◽  
Author(s):  
Hong Da Wu ◽  
Ying Gui Jia ◽  
Yu Yin ◽  
Lue Zhao
Keyword(s):  
Steam Reforming ◽  
Conversion Rate ◽  
Carbon Deposition ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Ethanol Conversion ◽  
Ethanol Steam Reforming ◽  
Impregnation Method ◽  
Catalyst Composition ◽  
Ethanol Steam

Y2O3-ZrO2 support was prepared by two-step precipitation method with ammonia and oxalic acid. A series of Cu-Ni/Y2O3-ZrO2 catalysts were prepared by impregnation method. The catalysts were investigated and then characterized by XRD and SEM results. The activity of catalysts in ethanol steam reforming was studied. The effects of the catalyst composition on the ethanol conversion rate were discussed and the catalysts inactivation phenomenon under the temperature ranging from 673K to 723K was then analyzed. The results show that 1Cu9Ni/1Y9Zr catalyst has higher activity in ethanol steam reforming, over which ethanol conversion rate is higher than 98% under the situation of 623K, while the inactivation of catalysts with Cu/Ni>3/7 at 673K~723K was caused by carbon deposition .

scholarly journals Oxy-Steam Reforming of Liquefied Natural Gas (LNG) on Mono- and Bimetallic (Ag, Pt, Pd or Ru)/Ni Catalysts

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1401
Author(s):  
Pawel Mierczynski ◽  
Magdalena Mosinska ◽  
Waldemar Maniukiewicz ◽  
Krasimir Vasilev ◽  
Malgorzata Iwona Szynkowska-Jozwik
Keyword(s):  
Natural Gas ◽  
Steam Reforming ◽  
Hydrogen Generation ◽  
Active Phase ◽  
Liquefied Natural Gas ◽  
Precipitation Method ◽  
Ni Catalyst ◽  
Ni Catalysts ◽  
Catalytic Systems ◽  
Production Of Hydrogen

This work presents, for the first time, the comparative physicochemical and reactivity studies of a range of bimetallic Pt-Ni, Pd-Ni, Ru-Ni, and Ag-Ni catalysts in the oxy-steam reforming (OSR) of liquefied natural gas (LNG) reaction towards hydrogen generation. In order to achieve the intended purpose of this work, a binary oxide CeO2·ZrO2 (1:2) support was prepared via a co-precipitation method. The catalysts’ physicochemical properties were studied using X-ray diffraction (XRD), BET, TPR-H2, TPD-NH3, SEM-EDS and XPS methods. The highest activity in the studied process was exhibited by the 1%Pt-5%Ni catalyst supported on CeO2·ZrO2 (1:2) system. The highest activity of this system is explained by the specific interactions occurring between the components of the active phase and between the components of the active phase and the carrier itself. The activity results showed that this catalytic system exhibited above 71% of the methane conversion at 600 °C and 60% yield of hydrogen formation. The results of this work demonstrate that the Pt-Ni and Ru-Ni catalytic systems hold promise to be applied in the production of hydrogen to power solid oxide fuel cells.

Unravelling the Role of Ceria in Improving the Stability of Mo2C Based Catalyst for Steam Reforming of Dimethyl Ether

2021 ◽  
Author(s):  
Jing-Hong Lian ◽  
Hongyi Tan ◽  
Changqing Guo ◽  
Li-sha Shen ◽  
Zhuo-Xin Lu ◽  
...  
Keyword(s):  
Dimethyl Ether ◽  
Steam Reforming ◽  
Water Oxidation ◽  
Molybdenum Carbide ◽  
Catalytic Performance ◽  
Significant Problem ◽  
The Stability

The inactivation of molybdenum carbide catalyst by water oxidation is a significant problem in steam reforming of dimethyl ether (SRD) reaction. In this work, the catalytic performance and stability of...

Fabrication of Ce-Promoted Ni/Al2O3 Methane Steam Reforming Catalysts by Impregnation

2020 ◽  
Vol 20 (7) ◽  
pp. 4327-4330
Author(s):  
Ye Sol Lim ◽  
Min-Jin Lee ◽  
Kyoung-Jin Lee ◽  
Sangjin Lee ◽  
Haejin Hwang
Keyword(s):  
Particle Size ◽  
Microstructural Evolution ◽  
Steam Reforming ◽  
Carbon Deposition ◽  
Methane Steam Reforming ◽  
Ni Catalysts ◽  
Good Dispersion ◽  
Methane Steam ◽  
Reforming Catalysts ◽  
Steam Reforming Catalysts

CeO2-promoted Ni/Al2O3 catalysts were fabricated by impregnation. The effects of the CeO2 promotion and impregnation order on the microstructural evolution and catalytic durability were investigated for methane steam reforming. The CeO2-promoter nanoparticles resulted in good dispersion and reduced particle size of Ni catalysts. The enhanced durability of CeO2-promoted Ni/Al2O3 catalysts might be associated with the depression of carbon deposition by the presence of CeO2-promoter nanoparticles.

Nanoparticles of Ni-Co Alloy Derived from Layered Double Hydroxides and Their Catalytic Performance for CO Methanation

NANO ◽  
2016 ◽  
Vol 11 (10) ◽  
pp. 1650118 ◽  
Author(s):  
Jingge Liu ◽  
Ang Cao ◽  
Jing Si ◽  
Lihong Zhang ◽  
Qinglan Hao ◽  
...  
Keyword(s):  
Metallic Nanoparticles ◽  
Carbon Deposition ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
Co Methanation ◽  
Transmission Electron ◽  
Temperature Programmed ◽  
The Stability ◽  
Double Hydroxides ◽  
Adsorption Desorption

Sintering of the active metallic nanoparticles and carbon deposition are the key problems faced for CO methanation catalysts. For overcoming those problems, bimetallic nanocatalyst is a promising route. In this work, a series of Al2O3 supported Ni-Co alloy catalysts were prepared by reducing NiCoAl layered double hydrotalcite (LDHs), and characterized with X-ray diffraction (XRD), temperature programmed reduction TPR, N2 adsorption-desorption, transmission electron microscopy (TEM) and temperature programed oxidation (TPO) techniques. The resultant catalysts were mesoporous with nanoparticles of Ni-Co alloy ranging from 7.9[Formula: see text]nm to 9.2[Formula: see text]nm which were highly dispersed in alumina matrix. The sample Ni7Co3-Al2O3 catalysts showed very good catalytic performance during the stability test at 500/600[Formula: see text]C for 300[Formula: see text]h, meanwhile exhibited excellent anti-sintering ability and anti-carbon deposition ability, owing to the formation of Ni-Co alloy and the feature of LDHs. This strategy for improving anti-sintering and anti-carbon deposition should be extendable for catalysts of other reactions.

Catalytic performance of supported Ni catalysts in partial oxidation and steam reforming of tar derived from the pyrolysis of wood biomass

2006 ◽  
Vol 115 (1-4) ◽  
pp. 254-262 ◽  
Author(s):  
Tomohisa Miyazawa ◽  
Takeo Kimura ◽  
Jin Nishikawa ◽  
Shigeru Kado ◽  
Kimio Kunimori ◽  
...  
Keyword(s):  
Partial Oxidation ◽  
Steam Reforming ◽  
Catalytic Performance ◽  
Wood Biomass ◽  
Ni Catalysts ◽  
Supported Ni Catalysts ◽  
Supported Ni

scholarly journals Hydrogen Production on Cu-Ni Catalysts via the Oxy-Steam Reforming of Methanol

Catalysts ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 273 ◽  
Author(s):  
Magdalena Mosinska ◽  
Natalia Stępińska ◽  
Waldemar Maniukiewicz ◽  
Jacek Rogowski ◽  
Agnieszka Mierczynska-Vasilev ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Physicochemical Properties ◽  
Steam Reforming ◽  
Catalytic Properties ◽  
Active Phase ◽  
Alloy Formation ◽  
High Catalytic Activity ◽  
Active System ◽  
Ni Catalysts ◽  
Steam Reforming Of Methanol

In this work, bimetallic Cu-Ni catalysts supported on binary oxides containing ZnO, ZrO2, CeO2 and Al2O3 were investigated in hydrogen production via the oxidative steam reforming of methanol (OSRM). Their physicochemical properties were extensively studied using various methods such as BET, TPR-H2, TPD-NH3, XRD, SEM-EDS, ToF-SIMS and XPS. The reactivity measurements showed that the active phase and support composition played an important role in the activity of the catalyst in the OSRM. The most active system at higher temperatures was 30% Cu–10% Ni/CeO2·Al2O3, with high catalytic activity attributed to the Cu0.8Ni0.2 alloy formation. In addition, the reactivity results showed that the most active catalyst exhibited high acidity and was easily reduced. At low temperatures, the best catalytic properties were exhibited by 30% Cu–10% Ni/ZrO2·Al2O3. The reactivity and physicochemical properties of the studied catalysts confirmed the crucial role of alloy composition on their catalytic properties in the oxy-steam reforming of methanol. The obtained results validate the possibility of using Cu-Ni catalysts for hydrogen production.

scholarly journals Structural Investigation of the Carbon Deposits on Ni/Al2O3 Catalyst Modified by CaO-MgO for the Biogas Dry Reforming Reaction

2020 ◽  
Vol 2 (1) ◽  
pp. 15
Author(s):  
Nikolaos D. Charisiou ◽  
Georgios I. Siakavelas ◽  
Victor Sebastian ◽  
Steven J. Hinder ◽  
Mark A. Baker ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Structural Investigation ◽  
Catalytic Performance ◽  
Dry Reforming ◽  
Ni Catalysts ◽  
Carbon Deposits ◽  
Carbon Structures ◽  
Spent Catalysts ◽  
Adsorption Desorption ◽  
Al2o3 Catalyst

Ni catalysts based on Al2O3 and Al2O3 modified with CaO-MgO were tested for the dry reforming of biogas (BDR). Time-on-stream experiments were carried out between 600 and 800 °C, and the spent catalysts were examined using a variety of characterization techniques including, N2 adsorption/desorption, thermogravimetric analysis (TGA), Raman spectroscopy, electron microscopy (STEM-HAADF and HR-TEM), and X-ray photoelectron spectroscopy (XPS). It was revealed that the carbon deposits consisted of carbon nanotubes and amorphous carbon for both samples. XPS studies showed the presence of Ni0 on both catalysts and Ni2O3/NiAl2O4 on the Ni/Al2O3 sample. The time-on-stream experiments showed that the Ni/CaO-MgO-Al2O3 catalyst is more resistant to deactivation and more active and selective for all temperatures under investigation. It was concluded that doping Al2O3 with CaO-MgO enhances catalytic performance as: (a) it helps to maintain highly dispersed Ni0 during the BDR as the interaction between metal and support is a stronger one, (b) it leads to the formation of carbon structures that are easier to oxidize, and (c) it facilitates the gasification of the carbon deposits because its increased surface basic sites enhance the adsorption of carbon dioxide.

Sign in / Sign up

Export Citation Format

Share Document