scholarly journals Carbon Monoxide Adsorption Studies on an Ru:Mn Bimetallic Alloy System for the Determination of Active Metal Sites

1996 ◽  
Vol 13 (6) ◽  
pp. 489-493 ◽  
Author(s):  
S. Tajammul Hussain
Keyword(s):  
High Surface ◽  
Co Adsorption ◽  
High Surface Area ◽  
Alloy System ◽  
Impregnation Method ◽  
Electronic Effects ◽  
Alumina Support ◽  
Bimetallic Alloy ◽  
Active Metal ◽  
Adsorption Of Co

A supported ruthenium:manganese bimetallic alloy system dispersed on a high surface area alumina support was prepared by the co-impregnation method. The adsorption of CO at atmospheric pressure was carried out in order to determine the number of active metal sites present. The data indicate that manganese was present as a covering layer on the surface of the ruthenium. With increasing manganese loading decreasing adsorption of CO was observed, indicating that the presence of manganese masked the active ruthenium sites responsible for CO adsorption. No CO adsorption occurred on isolated manganese sites. The data were interpreted in terms of the geometric and possible electronic effects caused by the addition of manganese.

A Green and Sustainable Approach for Acetalization of Benzaldehyde Using Tungstophosphoric Acid Loaded on Metal Oxide Catalysts

2019 ◽  
Vol 41 (5) ◽  
pp. 805-805
Author(s):  
Li Fanghao Li Fanghao ◽  
Li Chenjie Li Chenjie ◽  
Chen Junyi Chen Junyi ◽  
Wang Kuiwu Wang Kuiwu ◽  
Zhang Haijiang Zhang Haijiang ◽  
...  
Keyword(s):  
Metal Oxide ◽  
Condensation Reaction ◽  
High Surface ◽  
High Surface Area ◽  
Synergetic Effect ◽  
Reaction Model ◽  
Oxide Catalysts ◽  
Tungstophosphoric Acid ◽  
Impregnation Method ◽  
Metal Oxide Catalysts

A series of tungstophosphoric acid (H3PW12O40; HPW) loaded on metal oxide catalysts, namely H3PW12O40/M (M= TiO2, CeO2, ZrO2) was prepared by initial wetting impregnation method and their catalytic performances were also investigated during the condensation reaction of benzaldehyde with glycol. Among them, the 20 wt% H3PW12O40/TiO2 catalyst demonstrated highly active with superior acetal yield (90.1 %) and excellent durability. The high activity of the catalyst derived from high surface area, ultra-strong Brand#248;nsted acidity and synergetic effect of Brand#248;nsted-Lewis acid. Response surface methodology (RSM) based on Box-Behnken design (BBD) was used to optimize the course of the condensation reaction of benzaldehyde with glycol, and the optimal benzaldehyde glycol acetal yield (93.4 %) could be obtained. The optimized yield and the experimental results are similar. Moreover, under optimal reaction conditions, the activation energy (Ea) of reaction could be obtained through the kinetic study of the irreversible parallel reaction model, and the Ea was 23.24 kJ/mol.

scholarly journals Novel windows for “solar commodities”: a device for CO2 reduction using plasmonic catalyst activation

2015 ◽  
Vol 183 ◽  
pp. 249-259 ◽  
Author(s):  
Alexander Navarrete ◽  
Sergio Muñoz ◽  
Luis M. Sanz-Moral ◽  
Juergen J. Brandner ◽  
Peter Pfeifer ◽  
...  
Keyword(s):  
Light Transmission ◽  
High Surface ◽  
Stable Process ◽  
High Surface Area ◽  
Reaction System ◽  
Co2 Reduction ◽  
Impregnation Method ◽  
Catalyst Activation ◽  
Reverse Water Gas Shift ◽  
Rwgs Reaction

A novel plasmonic reactor concept is proposed and tested to work as a visible energy harvesting device while allowing reactions to transform CO2 to be carried out. Particularly the reverse water gas shift (RWGS) reaction has been tested as a means to introduce renewable energy into the economy. The development of the new reactor concept involved the synthesis of a new composite capable of plasmonic activation with light, the development of an impregnation method to create a single catalyst reactor entity, and finally the assembly of a reaction system to test the reaction. The composite developed was based on a Cu/ZnO catalyst dispersed into transparent aerogels. This allows efficient light transmission and a high surface area for the catalyst. An effective yet simple impregnation method was developed that allowed introduction of the composites into glass microchannels. The activation of the reaction was made using LEDs that covered all the sides of the reactor allowing a high power delivery. The results of the reaction show a stable process capable of low temperature transformations.

scholarly journals Bifunctional Materials for CO₂ Adsorption: Short Review

2021 ◽  
Vol 7 (2) ◽  
pp. 15-19
Author(s):  
S. M. Yusof ◽  
L. P. Teh
Keyword(s):  
Surface Area ◽  
Active Sites ◽  
Co2 Adsorption ◽  
High Surface ◽  
Co Adsorption ◽  
High Surface Area ◽  
Short Review ◽  
High Dispersion ◽  
High Porosity ◽  
Adsorption Performance

In recent years, there has been growing interest in adsorbents with high surface area, high porosity, high stability and high selectivity for CO2 adsorption. By the incorporation of the additive on the supports such as zeolite, silica, and carbon, the physicochemical properties of the adsorbent and CO2 adsorption performance can be enhanced. In this review, we focus on the overview of bifunctional materials (BFMs) for CO2 adsorption. The findings of this study suggests that the high surface area and high porosity of the support provide a good medium for high dispersion and accessibility of additives (amine or metal oxide), enhancing the CO2 adsorption efficiency. The excessive additive however may lead to a decrease of CO2 adsorption performance due to pore blockage and the decrease of active sites for CO2 interactions. The synergistic relationship of the supporting material and additive is significant towards the enhancement of CO2 adsorption.

Activity of Ethylene Epoxidation over High Surface Area Alumina Support Au–Ag Catalysts

2006 ◽  
Vol 39 (3) ◽  
pp. 321-326 ◽  
Author(s):  
Siriphong Rojluechai ◽  
Sumaeth Chavadej ◽  
Johannes W. Schwank ◽  
Vissanu Meeyoo
Keyword(s):  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Alumina Support ◽  
Ethylene Epoxidation ◽  
Ag Catalysts

scholarly journals Multifunctional and Environmentally Friendly TiO2–SiO2 Mesoporous Materials for Sustainable Green Buildings

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4226
Author(s):  
Ghedini ◽  
Menegazzo ◽  
Manzoli ◽  
Di Michele ◽  
Puglia ◽  
...  
Keyword(s):  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Environmentally Friendly ◽  
Green Building ◽  
Structural Features ◽  
Modulated Dsc ◽  
Synthetic Approach ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method

This work deals with the formulation of environmentally friendly, cheap, and readily-available materials for green building applications, providing the function of air purificator by improving the safety and the comfort of an indoor environment. High surface area TiO2–SiO2 samples, prepared by a simple, cost effective, and scalable synthetic approach, proved to be effective in maximizing the properties of each component, i.e., the photocatalytic properties of titania and the high surface area of silica. TiO2 was introduced onto an ordered mesoporous silica Santa Barbara Amorphous-15 (SBA-15), that is featured by interesting insulating features, by using an incipient wetness impregnation method. The photocatalytic activity was evaluated in gas phase oxidation of ethylbenzene, which was selected as model volatile organic compound (VOC) molecule. The morphological, textural and structural features along with the electronic properties, the hydrophilicity and heat capacity of the materials were investigated in depth by scanning electron microscopy, powder X-ray diffraction, N2 physisorption, diffuse reflectance UV-Vis, FT-IR spectroscopies, and modulated DSC (MDSC) dynamic scan. Outstanding performances in the ethylbenzene abatement results are promising for further application in the green building sector.

Surface Functionalization of Ordered Mesoporous Carbon by Immobilization of Diamine for Cobalt-Ion Adsorption

2014 ◽  
Vol 602-603 ◽  
pp. 300-303 ◽  
Author(s):  
Shu Ya Geng ◽  
Li Min Dong ◽  
Chen Wang ◽  
Tong Xiang Liang
Keyword(s):  
Surface Functionalization ◽  
Mesoporous Carbon ◽  
High Surface ◽  
High Surface Area ◽  
Mesoporous Structure ◽  
Adsorption Properties ◽  
Ordered Mesoporous Carbon ◽  
Ion Adsorption ◽  
Ordered Mesoporous ◽  
Adsorption Of Co

Highly ordered mesoporous carbon (CMK-3) was fabricated for the adsorption of cobalt from aqueous solutions. With the high surface area of1112.7m2/g and pore size of 17.2 nm, its abundant mesopores were benefit for providing channels for liquid propagate. In order to improve the adsorption properties,CMK-3 was modified by hydroxylation and amination. Fourier transform infrared (FTIR) spectroscopy can be seen that the amino group was successfully grafted onto the CMK-3 with highly ordered mesoporous structure. The functionalized ordered mesoporous carbon (CMK-3-EDA) ,CMK-3 and CMK-3-OX were used as absents for the adsorption of Co (II) from aqueous solution. The results showed that CMK-3-EDA were more twice effective in adsorption of Co (II) compared to CMK-3, which indicated that CMK-3-EDA had great potential for the adsorption of Co (II).

Effect of Pd on CH4 Reforming with CO2 Catalyzed by Ni over Mixed Titian –Alumina Support

2012 ◽  
Vol 476-478 ◽  
pp. 513-518 ◽  
Author(s):  
A.S. Al–Fatesh ◽  
A.H Fakeeha ◽  
A.E. Abasaeed
Keyword(s):  
Catalyst Activity ◽  
Poor Performance ◽  
Feed Ratio ◽  
Impregnation Method ◽  
Catalytic Reforming ◽  
Alumina Support ◽  
Active Metal ◽  
Spent Catalysts ◽  
Α Al2o3 ◽  
Effect Of Pd

The catalytic reforming of methane with carbon dioxide using Pd promoter on 1% Ni/20%TiO2-P25+80%α-Al2O3 was investigated. An experimental study was carried out using the catalyst prepared by impregnation method. The catalysts were dried at 120°C and calcined at 900°C. The reforming reactions were carried out using CO2/CH4/N2 feed ratio of 5/5/1, F/W=44 ml/min.gcat and reaction temperature of 700°C. The effect of nominal load of Pd ranging from 0.0 to 0.48 was studied by evaluating catalyst activity, stability, coke and (H2/CO) ratio. The prepared catalysts were tested in micro reactor at atmospheric pressure. The effluents were analyzed using an online gas chromatography equipped with a thermal conductivity detector. EDS and TGA for the fresh and spent catalysts were evaluated. Results indicate that the addition of small amounts of Pd is preferable in terms of activity and carbon deposition than higher Pd loading. For instance, 0.01%Pd gives a conversion of 78.4 for CH4 and 4.9% deactivation factor. While, 0.48%Pd gives a conversion of 75.6 for CH4 and 29.9% deactivation factor. Thus higher loading of Pd causes the catalyst to show poor performance with lower conversion and higher carbon formations. It can be concluded that Pd promoter has an optimal concentration with respect to the active metal of the catalyst beyond which the performance deteriorates.

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