scholarly journals Catalytic Combustion of Voc in Air Stream Over Bimetallic Chromium-Copper Supported On Sicl4-Modified H-Zsm-5 Catalyst

2010 ◽  
Vol 7 (1) ◽  
pp. 37-45
Author(s):  
A.Z. Abdullah ◽  
M.Z. Abu Bakar ◽  
S. Bhatia
Keyword(s):  
Performance Studies ◽  
Catalytic Combustion ◽  
Surface Acidity ◽  
Silicon Tetrachloride ◽  
Metal Species ◽  
Pore Characteristics ◽  
Air Stream ◽  
Voc Combustion ◽  
Redox Ability

The performance of chromium (Cr) and copper (Cu) on silicon tetrachloride modified H-ZSM-5 (SiCl4-Z) catalyst in VOC combustion is reported. H-ZSM-5, modified with SiCl4 at 500?C for 3 h was impregnated with 1.0 wt. % of Cr and 0.5 wt. % of Cu. Performance studies were carried out at GHSV of 3,800 to 32,000 h-1 with 2,000 to 35,000 ppm of VOC. Changes in the activity of Cr-Cu/ SiCl4-Z were ascribed to extra framework deposits, surface acidity and pore characteristics. Cr-Cu/SiCl4-Z catalyst was more stable to coking, humidity and HCl than Cr-Cu/Z. In the combustion of chlorinated VOC, the chlorination of metal species deactivated the catalyst by rendering lower redox ability.

scholarly journals Catalytic Combustion of Low Concentration Methane over Catalysts Prepared from Co/Mg-Mn Layered Double Hydroxides

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Hongfeng Liu ◽  
Xingrui Fu ◽  
Xiaole Weng ◽  
Yue Liu ◽  
Haiqiang Wang ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Catalytic Activity ◽  
Layered Double Hydroxides ◽  
Catalytic Combustion ◽  
Mixed Oxides ◽  
Oxygen Mobility ◽  
Catalytic Combustion Of Methane ◽  
Redox Ability ◽  
Double Hydroxides ◽  
Mn Oxides

A series of Co/Mg-Mn mixed oxides were synthesized through thermal decomposition of layered double hydroxides (LDHs) precursors. The resulted catalysts were then subjected for catalytic combustion of methane. Experimental results revealed that the Co4.5Mg1.5Mn2LDO catalyst possessed the best performance with theT90=485°C. After being analyzed via XRD, BET-BJH, SEM, H2-TPR, and XPS techniques, it was observed that the addition of cobalt had significantly improved the redox ability of the catalysts whilst certain amount of magnesium was essential to guarantee the catalytic activity. The presence of Mg was helpful to enhance the oxygen mobility and, meanwhile, improved the dispersion of Co and Mn oxides, preventing the surface area loss after calcination.

A Kinetic Study of Catalytic Combustion of Ethyl Acetate and Benzene in Air Stream over Cr-ZSM-5 Catalyst

2003 ◽  
Vol 42 (24) ◽  
pp. 6059-6067 ◽  
Author(s):  
Ahmad Zuhairi Abdullah ◽  
Mohamad Zailani Abu Bakar ◽  
Subhash Bhatia
Keyword(s):  
Ethyl Acetate ◽  
Kinetic Study ◽  
Catalytic Combustion ◽  
Air Stream

Trade-off between redox ability and reactive behaviors for acrylonitrile selective catalytic combustion over the Cu-Ce-based UZM-9 catalysts

2021 ◽  
Vol 610 ◽  
pp. 117960
Author(s):  
Xiaoli Wei ◽  
Sheng Wang ◽  
Changjun Ni ◽  
Mingzhe Wang ◽  
Shudong Wang
Keyword(s):  
Catalytic Combustion ◽  
Trade Off ◽  
Redox Ability

Montmorillonite intercalated with SiO2, SiO2-Al2O3 or SiO2-TiO2 pillars by surfactant-directed method as catalytic supports for DeNOx process

2014 ◽  
Vol 68 (9) ◽  
Author(s):  
Lucjan Chmielarz ◽  
Andrzej Kowalczyk ◽  
Magdalena Wojciechowska ◽  
Paweł Boroń ◽  
Barbara Dudek ◽  
...  
Keyword(s):  
Transition Metal ◽  
Catalytic Reduction ◽  
Surface Acidity ◽  
High Surface ◽  
High Surface Area ◽  
Catalytic Performance ◽  
Pillared Clay ◽  
Metal Species ◽  
Reduction Of No ◽  
Catalytic Supports

AbstractThe intercalation of natural montmorillonite with SiO2, SiO2-Al2O3 or SiO2-TiO2 pillars by the surfactant-directed method resulted in the formation of high surface area porous materials; these were tested as catalytic supports for the process of selective catalytic reduction of NO (DeNOx). The incorporation of titanium or aluminium into the structure of the silica pillars significantly increased the surface acidity of the clay samples. Iron and copper were deposited onto the surface of the pillared clays mainly in the form of monomeric isolated cations and oligomeric metal oxide species. The contribution of the latter species was higher in the clay intercalated with SiO2-TiO2 pillars than in the samples modified with SiO2 and SiO2-Al2O3 pillars. The pillared clay-based catalysts were active in the DeNOx process but, in this group, the best results were obtained for the clay intercalated with SiO2-TiO2 pillars and doped with iron and copper. The catalytic performance of the samples is discussed in respect of their surface acidity and active forms of transition metal species deposited.

scholarly journals Catalytic Combustion With Steam Injection

1982 ◽  
Author(s):  
David N. Anderson ◽  
Robert R. Tacina
Keyword(s):  
Experimental Study ◽  
Catalytic Combustion ◽  
Fuel Injection ◽  
Steam Injection ◽  
Combustion Performance ◽  
Air Stream

This report describes an experimental study to determine: (1) if catalytic combustion performance is degraded when steam is injected into the air-stream, and (2) if steam-assisted fuel injection might eliminate the upstream burning problems which have occurred in past studies of catalytic combustion of residual fuels.

scholarly journals Promoting Effect of Ti Species in MnOx-FeOx/Silicalite-1 for the Low-Temperature NH3-SCR Reaction

Catalysts ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 566
Author(s):  
Jialiang Gu ◽  
Rudi Duan ◽  
Weibin Chen ◽  
Yan Chen ◽  
Lili Liu ◽  
...  
Keyword(s):  
Catalytic Reduction ◽  
Surface Acidity ◽  
Space Velocity ◽  
Acid Sites ◽  
Impregnation Method ◽  
Promoting Effect ◽  
Nh3 Scr ◽  
Nh3 Adsorption ◽  
Redox Ability

Manganese and iron oxides catalysts supported on silicalite-1 and titanium silicalite-1 (TS-1) are synthesized by the wet impregnation method for the selective catalytic reduction (SCR) of NOx with NH3 (NH3-SCR), respectively. The optimized catalyst demonstrates an increased NOx conversion efficiency of 20% below 150 °C, with a space velocity of 18,000 h−1, which can be attributed to the incorporation of Ti species. The presence of Ti species enhances surface acidity and redox ability of the catalyst without changing the structure of supporter. Moreover, further researches based on in situ NH3 adsorption reveal that Lewis acid sites linked to Mn4+ on the surface have a huge influence on the improvement of denitration efficiency of the catalyst at low temperatures.

scholarly journals Experimental study on the properties of modern blue clay brick for Kaifeng People's Conference Hall

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shaochun Ma ◽  
Youwen Wu ◽  
Peng Bao
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Performance Studies ◽  
Clay Brick ◽  
X Ray Diffraction ◽  
Pore Characteristics ◽  
Clay Bricks ◽  
Building Assessment ◽  
Current Design ◽  
Softening Coefficient

AbstractThis article presents building assessment research comprising on-site inspections, indoor scientific tests, and material performance studies on the wall blue clay bricks in the Kaifeng People’s Conference Hall, objectively developing an enhanced scientific understanding to renovate modern buildings. Using X-ray diffraction (XRD), scanning electron microscopy (SEM), alongside a parametric study of density, moisture content, water absorption, void ratio, frosting, compressive strength, and softening coefficient in assessing the material health of the blue clay bricks and it’s non-key parts, in developing “appropriate and compatible renovation” to repair contemporaneous buildings. The composition, pore characteristics, weathering degree, and mechanical properties of the blue clay brick samples were analyzed. These parameters showed that blue clay brick fired at less than 1000 °C; the main mineral composition as quartz, followed by albite, mica, and anorthite. Its density was 1.573 g/cm3, less than the 1.70 g/cm3 of ordinary clay brick. According to the standards, the water absorption was greater than that of regular sintered bricks by more than 18% and was slightly frosted. Compressive strength being less than MU10 did not meet the current design specifications for masonry. Its softening coefficient was between 0.70 and 0.85, but its water resistance was relatively good. The research results provide an essential reference for judging the health and longevity of modern buildings to achieve scientific guidelines for practical protection.

scholarly journals The Deactivation Mechanism of the Mo-Ce/Zr-PILC Catalyst Induced by Pb for the Selective Catalytic Reduction of NO with NH3

Nanomaterials ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2641
Author(s):  
Chenxi Li ◽  
Jin Cheng ◽  
Qing Ye ◽  
Fanwei Meng ◽  
Xinpeng Wang ◽  
...  
Keyword(s):  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Surface Acidity ◽  
Catalyst Activity ◽  
Acid Sites ◽  
Nh3 Scr ◽  
Highly Active ◽  
Negative Effect ◽  
Redox Ability ◽  
Deactivation Mechanism

As a heavy metal, Pb is one component in coal-fired flue gas and is widely considered to have a strong negative effect on catalyst activity in the selective catalytic reduction of NOx by NH3 (NH3-SCR). In this paper, we investigated the deactivation mechanism of the Mo-Ce/Zr-PILC catalyst induced by Pb in detail. We found that NO conversion over the 3Mo4Ce/Zr-PILC catalyst decreased greatly after the addition of Pb. The more severe deactivation induced by Pb was attributed to low surface area, lower amounts of chemisorbed oxygen species and surface Ce3+, and lower redox ability and surface acidity (especially a low number of Brønsted acid sites). Furthermore, the addition of Pb inhibited the formation of highly active intermediate nitrate species generated on the surface of the catalyst, hence decreasing the NH3-SCR activity.

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