scholarly journals Enhanced Reforming of Tar Based on Double-Effect Ni/CaO–Ca12Al14O33 Catalysts: Modified by Ce, Mg, and Fe

2021 ◽  
Vol 9 ◽  
Author(s):  
Panlei Wang ◽  
Weidong Zhang ◽  
Zhenyu Yu ◽  
Huaqing Xie ◽  
Mi Zhou ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Steam Reforming ◽  
Active Component ◽  
Double Effect ◽  
Coprecipitation Method ◽  
Fe Doping ◽  
Mg Doping ◽  
The Stability ◽  
Tar Reforming ◽  
Mg Doped

The double-effect Ni-based catalysts, modified with Ce, Mg, and Fe and synthesized by the coprecipitation method, were applied into the enhanced steam reforming process of real tar. The effects of the catalysts with different doping mass proportions (3, 6, 9, and 12%) of Ce, Mg, and Fe on the H2 yield, and H2 and CO2 concentrations were studied. The results revealed that the tar reforming efficiency was improved with appropriate proportions of the additives added. The Ce- or Mg-doped catalyst could change the distribution or morphology of the active component Ni. The modified catalyst with 6% Ce or 3% Mg doping showed the best catalytic activity in the reforming experiment, with the H2 yield reaching 86.84% or 85.22%, respectively. The Fe-doped catalyst could form an Ni–Fe alloy and improve the stability of the catalyst, and the better catalytic activity can be obtained at 9 and 12% Fe doping, with the H2 yield reaching 85.54 and 85.80%, respectively.

Effect of Sintered Magnesium Substituted Biphasic Calcium Phosphate (Mg-BCP)

2020 ◽  
Vol 1010 ◽  
pp. 567-572
Author(s):  
M.H.M. Marahat ◽  
Hasmaliza M. Mohamad ◽  
Shah Rizal Kasim
Keyword(s):  
Calcium Phosphate ◽  
Biphasic Calcium Phosphate ◽  
Chemical Constituents ◽  
Precipitation Method ◽  
Sintered Pellet ◽  
Mg Doping ◽  
Before And After ◽  
Quantification Analysis ◽  
The Stability ◽  
Mg Doped

Biphasic Calcium Phosphate (BCP) is a ceramic material that consisting of two phases which is Hydroxyapatite (HA) and β-Tricalcium Phosphate (β-TCP). In this work, BCP and Mg-BCP (Mg Doped) was synthesized using aqueous precipitation method at standard room temperature and pressure. The synthesized powder was pressed into pellet and sintered at three consecutive temperatures of 800 °C, 900 °C, and 1000 °C. The sintered pellet was characterized using XRD to obtained the quantification analysis on phases presence and to study the crystal orientation of HA and β-TCP before and after Mg doping was introduced. FTIR was used to determine chemical constituents of synthesized powders. Diameter shrinkage analysis was performed to study the effect of temperatures on the densification of the pellet body and SEM was used to observed the morphology of each pellet. Based on the XRD result, the Mg doping is affecting the stability of the phases presence and the crystal lattice creating a distortion due to the substitution of smaller Mg ion. Analysis on the SEM morphology have shown that Mg doped BCP resulting a dense structure with less formation of porosity, necking was formed clearly at temperatures of 900 °C to 1000 °C.

Catalytic activity of nanostructured plate-type Cu-based on ZnO nanorods promoted by additive metals for oxidative steam reforming of methanol

2011 ◽  
Vol 1303 ◽  
Author(s):  
Chien-Cheng Li ◽  
Ran-Jin Lin ◽  
Hong-Ping Lin ◽  
Li-Chyong Chen ◽  
Kuei-Hsien Chen
Keyword(s):  
Stainless Steel ◽  
Catalytic Activity ◽  
Electroless Plating ◽  
Steam Reforming ◽  
Zno Nanorods ◽  
Steam Reforming Of Methanol ◽  
The Stability ◽  
Steel Substrates ◽  
Highly Porous ◽  
Plate Type

ABSTRACTThe Cu-based film catalysts with various additive metals have been successfully prepared by the electroless plating on ZnO nanorods/stainless steel substrates. The microstructure features of the Cu-based films are highly porous and composed of plate-type grains. The addition of zirconium, aluminum, and iron into Cu-based film catalyst can improve the activity and the stability of the film catalysts. The catalytic durability of the Cu-based film catalysts has also been improved by addition of Zr, Al, and Fe into Cu-based films. This is attributed to the formation of the stable ZrO2, Al2O3, and Fe2O3 nanoparticles with good dispersion in the films.

scholarly journals Catalytic Hot Gas Cleanup of Biomass Gasification Producer Gas via Steam Reforming Using Nickel-Supported Clay Minerals

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1875
Author(s):  
Prashanth Reddy Buchireddy ◽  
Devin Peck ◽  
Mark Zappi ◽  
Ray Mark Bricka
Keyword(s):  
Catalytic Activity ◽  
Surface Area ◽  
Steam Reforming ◽  
Catalyst Deactivation ◽  
Nickel Content ◽  
Coke Formation ◽  
Biomass Gasification ◽  
Supported Nickel Catalyst ◽  
Fuel Gas ◽  
Removal Efficiencies

Amongst the issues associated with the commercialization of biomass gasification, the presence of tars has been one of the most difficult aspects to address. Tars are an impurity generated from the gasifier and upon their condensation cause problems in downstream equipment including plugging, blockages, corrosion, and major catalyst deactivation. These problems lead to losses of efficiency as well as potential maintenance issues resulting from damaged processing units. Therefore, the removal of tars is necessary in order for the effective operation of a biomass gasification facility for the production of high-value fuel gas. The catalytic activity of montmorillonite and montmorillonite-supported nickel as tar removal catalysts will be investigated in this study. Ni-montmorillonite catalyst was prepared, characterized, and tested in a laboratory-scale reactor for its efficiency in reforming tars using naphthalene as a tar model compound. Efficacy of montmorillonite-supported nickel catalyst was tested as a function of nickel content, reaction temperature, steam-to-carbon ratio, and naphthalene loading. The results demonstrate that montmorillonite is catalytically active in removing naphthalene. Ni-montmorillonite had high activity towards naphthalene removal via steam reforming, with removal efficiencies greater than 99%. The activation energy was calculated for Ni-montmorillonite assuming first-order kinetics and was found to be 84.5 kJ/mole in accordance with the literature. Long-term activity tests were also conducted and showed that the catalyst was active with naphthalene removal efficiencies greater than 95% maintained over a 97-h test period. A little loss of activity was observed with a removal decrease from 97% to 95%. To investigate the decrease in catalytic activity, characterization of fresh and used catalyst samples was performed using thermogravimetric analysis, transmission electron microscopy, X-ray diffraction, and surface area analysis. The loss in activity was attributed to a decrease in catalyst surface area caused by nickel sintering and coke formation.

Effect of the ionizing radiation on the catalytic activity of the BASF K-3-10 catalyst in the low-temperature conversion of carbon monoxide by water vapour. Stability of the radiation catalytic effects

1986 ◽  
Vol 51 (8) ◽  
pp. 1571-1578 ◽  
Author(s):  
Alois Motl
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Low Temperature ◽  
Catalytic Effect ◽  
Catalytic Properties ◽  
Beta Radiation ◽  
Fast Neutrons ◽  
Time Interval ◽  
The Stability ◽  
Catalytic Effects

The radiation catalytic properties of the BASF K-3-10 catalyst were studied, namely the dependence of these effects on the time interval between the catalyst irradiation and the reaction itself and also on the length of the catalyst use. The catalytic effects decrease exponentially with the interval between the irradiation and the reaction if the catalyst is kept in the presence of air. The stability of effects induced by various types of radiations increases in the sequence beta radiation - gamma radiation - fast neutrons. The radiation catalytic effect stability in the reaction increases in the same sequence.

scholarly journals Catalytic Activity of Oxidation-Reduction Pre-Treated Ni3Al for Methane Steam Reforming

2010 ◽  
Vol 89-91 ◽  
pp. 645-650 ◽  
Author(s):  
Ya Xu ◽  
Dong Hyun Chun ◽  
Jun Hyuk Jang ◽  
Masahiko Demura ◽  
Dang Moon Wee ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Steam Reforming ◽  
Active Surface ◽  
Methane Steam Reforming ◽  
Reduction Treatment ◽  
Highly Active ◽  
Methane Steam ◽  
Oxidation Reduction ◽  
Pre Treatment ◽  
Oxidation In Air

The catalytic activity of oxidation-reduction pre-treated Ni3Al powder for methane steam reforming was examined. The oxidation-reduction pre-treatment consisted of two steps: oxidation in air at various temperatures from 973 to 1373 K, and then followed by reduction in H2 at 873 K. It was found that the oxidation-reduction treatments significantly reduced the onset temperature of activity, i.e., improved the activity of Ni3Al powder at low temperatures. The characterization of Ni3Al surface showed that an outer surface layer of fine NiO particles were formed on the surface of Ni3Al after oxidation. These NiO particles were reduced to metallic Ni by the subsequent reduction treatment, resulting in the high activity for methane steam reforming. These results indicate that the Ni3Al can form highly active surface structure with oxidation-reduction treatment, having excellent heat resistance.

Liquid-Phase Hydrogenation to 2, 4-Tolylenediamine over Supported HY Catalysts

2012 ◽  
Vol 512-515 ◽  
pp. 2381-2385
Author(s):  
Xue Mei Zhang ◽  
Feng Xing Niu
Keyword(s):  
Catalytic Activity ◽  
Liquid Phase ◽  
Catalytic Hydrogenation ◽  
Active Component ◽  
Experimental Results ◽  
Mass Ratio ◽  
Liquid Phase Hydrogenation ◽  
Catalytic Test

We have successfully prepared a novel passivation Ni/HY catalyst by the technologies of macerate-precipitatio.The catalysts are comprised of two contents: HY as carrier, Ni as active component，and we put it into the process of preparating aromatic amines.The nature of the catalysts was discussed based on the characterization results of BET , IR , SEM , XRD , TEM ,TPD , XPS and TPR . The catalytic hydrogenation technology for 2,4-dinitrobenzene in liquid phase can be an attractive and elegant routine for production of 2,4-tolylenediamine. The catalytic activity is evaluated at 2.2 MPa, 90 °C, 750r/min, solvent with reaction materials mass ratio of 60, catalyst with reaction materials mass ratio of 0.1. In the catalytic test, The experimental results over the catalyst showed that 2,4-dinitrobenzene and 2,4-tolylenediamine conversion and selective of 99.88% and 99.16% were obtained respectively.It is found that the catalyst is highly dispersion, stable, and reusable. No obvious deactivation of the catalyst was observed after repeated using twelve times.

scholarly journals Preparation of Palladium-Impregnated Ceria by Metal Complex Decomposition for Methane Steam Reforming Catalysis

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Worawat Wattanathana ◽  
Suttipong Wannapaiboon ◽  
Chatchai Veranitisagul ◽  
Navadol Laosiripojana ◽  
Nattamon Koonsaeng ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Metal Complex ◽  
Steam Reforming ◽  
Organic Ligand ◽  
Methane Steam Reforming ◽  
Microwave Assisted ◽  
Methane Steam ◽  
Bet Specific Surface Area ◽  
Ceria Catalysts

Palladium-impregnated ceria materials were successfully prepared via an integrated procedure between a metal complex decomposition method and a microwave-assisted wetness impregnation. Firstly, ceria (CeO2) powders were synthesized by thermal decomposition of cerium(III) complexes prepared by using cerium(III) nitrate or cerium(III) chloride as a metal source to form a metal complex precursor with triethanolamine or benzoxazine dimer as an organic ligand. Palladium(II) nitrate was consequently introduced to the preformed ceria materials using wetness impregnation while applying microwave irradiation to assist dispersion of the dopant. The palladium-impregnated ceria materials were obtained by calcination under reduced atmosphere of 10% H2 in He stream at 700°C for 2 h. Characterization of the palladium-impregnated ceria materials reveals the influences of the metal complex precursors on the properties of the obtained materials. Interestingly, the palladium-impregnated ceria prepared from the cerium(III)-benzoxazine dimer complex revealed significantly higher BET specific surface area and higher content of the more active Pdδ+ (δ > 2) species than the materials prepared from cerium(III)-triethanolamine complexes. Consequently, it exhibited the most efficient catalytic activity in the methane steam reforming reaction. By optimization of the metal complex precursors, characteristics of the obtained palladium-impregnated ceria catalysts can be modified and hence influence the catalytic activity.

A new three-phase heterocrystal catalysts and their superior treatment efficiency for tetracycline

2016 ◽  
Vol 10 (03) ◽  
pp. 1750015
Author(s):  
Feng-Rui Wang ◽  
Hui-Ping Sun ◽  
Yan Wang ◽  
Jin-Ku Liu ◽  
Yi Fang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Band Structure ◽  
Antibiotic Residues ◽  
Treatment Efficiency ◽  
Electron Hole ◽  
Three Phase ◽  
Catalytic Material ◽  
Water Based ◽  
The Stability ◽  
Functional Components

An easy recyclable and interesting Ag3PO4@Pt@TiO2 (APTP) three-phase heterocrystal chains were self-assembled by the cohesive action and chemical construction of polyvinylpyrrolidone (PVP). We found that a new electron–hole transmission path has been built via the rematch of the band structure of Ag3PO4, Pt and TiO2 which extends the light absorption and promoted the electron–hole separation to treat the antibiotic residues in the water. Based on the thorough investigations, a new catalytic material was provided for antibiotics degradation. The catalytic activity of APTP toward the degradation of tetracycline solution was enhanced by 166.67% and the stability increased remarkably compared with pure Ag3PO4 through the integration of different functional components.

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