Catalytic Activity of Epitaxially Grown Ni Supported Catalysts

1974 ◽  
Vol 13 (S2) ◽  
pp. 489 ◽  
Author(s):  
G. Dalmai-Imelik ◽  
C. Leclercq ◽  
J. Massardier ◽  
A. Maubert-Franco ◽  
A. Zalhout
Keyword(s):  
Catalytic Activity ◽  
Supported Catalysts ◽  
Ni Supported Catalysts

Characterization and Catalytic Activity of Poly(4-Vinylpyridine-Co-Divinylbenzene)-Co2+ Complex

2005 ◽  
Vol 494 ◽  
pp. 363-368 ◽  
Author(s):  
D. Lončarević ◽  
Ž. Čupić
Keyword(s):  
Catalytic Activity ◽  
Molecular Level ◽  
Supported Catalysts ◽  
Lone Pair ◽  
Polymer Support ◽  
Polymeric Complex ◽  
Reaction Conditions ◽  
Pyridine Nitrogen ◽  
Nitrogen Lone Pair ◽  
Thermal Stability Of

Poly(4-vinylpyridine-co-divinylbenzene)-Co2+ was characterized using infrared spectroscopy (IR), thermogravimetric analysis (TG-DTA), N2-physisorption and polarography. Thermal analysis suggests sufficient thermal stability of the polymer support, under reaction conditions. From polarography measurements, the Co2+ content on polymer-supported catalysts is estimated and it was proved that no significant leaching occurred during the activity tests. At the molecular level, FTIR of P4VP-DVB-Co2+ reveals that the pyridine nitrogen lone pair coordinates to the metal center in the polymeric complex. The obtained P4VP-DVB-Co2+ catalysts performed interesting catalytic activity in reaction of the cyclohexane oxidation with air, indicating that increasing Co2+ content lowers the initiation temperature and raises the decomposition of cyclohexylhydroperoxide.

scholarly journals The Effect of Catalyst Support on the Decomposition of Methane to Hydrogen and Carbon

1970 ◽  
Vol 5 (1) ◽  
Author(s):  
Sharif Hussein Sharif Zein Abdul Rahman Mohamed
Keyword(s):  
Supported Catalysts ◽  
Catalyst Activity ◽  
Catalyst Support ◽  
Methane Decomposition ◽  
Filamentous Carbon ◽  
Transmission Electron ◽  
Decomposition Of Methane ◽  
Long Lifetime ◽  
The Relationship ◽  
Ni Supported Catalysts

Decomposition of methane into carbon and hydrogen over Cu/Ni supported catalysts was investigated. The catalytic activities and the lifetimes of the catalysts were studied. Cu/Ni supported on TiO2 showed high activity and long lifetime for the reaction. Transmission electron microscopy (TEM) studies revealed the relationship between the catalyst activity and the formation of the filamentous carbon over the catalyst after methane decomposition. While different types of filamentous carbon formed on the various Cu/Ni supported catalysts, an attractive carbon nanotubes was observed in the Cu/Ni supported on TiO2. Key Words:  Methane decomposition, carbon nanotube, Cu/Ni supported catalysts.

scholarly journals Chiral MnIII (Salen) Immobilized on Organic Polymer/Inorganic Zirconium Hydrogen Phosphate Functionalized with 3-Aminopropyltrimethoxysilane as an Efficient and Recyclable Catalyst for Enantioselective Epoxidation of Styrene

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 212 ◽  
Author(s):  
Xiaochuan Zou ◽  
Yue Wang ◽  
Cun Wang ◽  
Kaiyun Shi ◽  
Yanrong Ren ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Supported Catalysts ◽  
Organic Polymer ◽  
Solid Catalyst ◽  
Homogeneous Catalyst ◽  
Hydrogen Phosphate ◽  
Characterization Methods ◽  
Salen Complexes ◽  
Enantioselective Epoxidation ◽  
Better Than

Organic polymers/inorganic zirconium hydrogen phosphate (ZSPP, ZPS-IPPA, and ZPS-PVPA) functionalized with 3-aminopropyltrimethoxysilane were prepared and used to support chiral MnIII (salen) complexes (Jacobsen’s catalyst). Different characterization methods demonstrated that the chiral MnIII (salen) complexes was successfully supported on the surface of the carrier (ZSPP, ZPS-IPPA, or ZPS-PVPA) through a 3-aminopropyltrimethoxysilane group spacer. The supported catalysts effectively catalyzed epoxidation of styrene with m-chloroperbenzoic acid (m-CPBA) as an oxidant in the presence of N-methylmorpholine N-oxide (NMO) as an axial base. These results (ee%, 53.3–63.9) were significantly better than those achieved under a homogeneous counterpart (ee%, 46.2). Moreover, it is obvious that there was no significant decrease in catalytic activity after the catalyst 3 was recycled four times (cons%: from 95.0 to 92.6; ee%: from 64.7 to 60.1). Further recycles of catalyst 3 resulted in poor conversions, although the enantioselectivity obtained was still higher than that of corresponding homogeneous catalyst even after eight times. After the end of the eighth reaction, the solid catalyst was allowed to stand in 2 mol/L of dilute hydrochloric acid overnight, prompting an unexpected discovery that the catalytic activity of the catalyst was recovered again at the 9th and 10th cycles of the catalyst.

Sulfur adsorption and release properties of bimetallic Pd–Ni supported catalysts

2015 ◽  
Vol 408 ◽  
pp. 161-171 ◽  
Author(s):  
Yulia Hilli ◽  
Niko M. Kinnunen ◽  
Mika Suvanto ◽  
Auli Savimäki ◽  
Kauko Kallinen ◽  
...  
Keyword(s):  
Supported Catalysts ◽  
Adsorption And Release ◽  
Sulfur Adsorption ◽  
Ni Supported Catalysts

Catalytic Performance of SO2 by Colloidal Gold Supported on Nano γ-Fe2O3

2010 ◽  
Vol 178 ◽  
pp. 65-70 ◽  
Author(s):  
Sheng Rui Xu ◽  
Qin Shuai ◽  
Jin Hua Cheng ◽  
Xiao Ge Wang
Keyword(s):  
Gas Chromatography ◽  
Gold Nanoparticles ◽  
Catalytic Activity ◽  
Metal Oxides ◽  
Water Vapour ◽  
Colloidal Gold ◽  
Supported Catalysts ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Sulfate Species

A new catalyst of gold supported on nanometal oxide for oxidation of SO2 was developed. Deposition-precipitation method was used to prepare gold-based catalysts. The catalytic activity of the catalysts was evaluated by determining the concentration of SO2 with gas chromatography under reaction temperature from 100 to 700°C. The results showed that there was an enhancement of catalytic activity when gold nanoparticles were dispersed on the surface of nano-metal oxides, furthermore, γ-Fe2O3 showed the highest activity as the support of the colloidal gold supported catalysts among the nanometal oxides including γ-Fe2O3, Fe2O3, ZnO, and Al2O3. It was also found that water vapour in the reaction enhanced the catalytic activity of Au/γ-Fe2O3. The Au/γ-Fe2O3 was characterized by XRD and FTIR methods, which indicated that the gold nanoparticles were dispersed on the γ-Fe2O3 support and sulfate species were formed on the surface of catalysts.

scholarly journals Effect of the oxygen coordination environment of Ca–Mn oxides on the catalytic performance of Pd supported catalysts for aerobic oxidation of 5-hydroxymethyl-2-furfural

2019 ◽  
Vol 9 (23) ◽  
pp. 6659-6668 ◽  
Author(s):  
Jie Yang ◽  
Haochen Yu ◽  
Yanbing Wang ◽  
Fuyuan Qi ◽  
Haodong Liu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Charge Transfer ◽  
Active Sites ◽  
Supported Catalysts ◽  
Aerobic Oxidation ◽  
Oxygen Adsorption ◽  
Catalytic Performance ◽  
Coordination Environment ◽  
Oxygen Coordination ◽  
Mn Oxides

Pd/CaMn2O4 provides ideal active sites for oxygen adsorption and desorption, resulting in the promoted charge transfer ability and catalytic activity.

scholarly journals Effect of support acidity during selective hydrogenolysis of glycerol over supported palladium–ruthenium catalysts

2020 ◽  
Vol 378 (2176) ◽  
pp. 20200055
Author(s):  
Susana Guadix-Montero ◽  
Alba Santos-Hernandez ◽  
Andrea Folli ◽  
Meenakshisundaram Sankar
Keyword(s):  
Catalytic Activity ◽  
Supported Catalysts ◽  
Bond Cleavage ◽  
Strong Acid ◽  
Acid Sites ◽  
Ruthenium Catalysts ◽  
Impregnation Method ◽  
Selective Hydrogenolysis ◽  
Strong Acid Sites ◽  
Effect Of Support

We report the role of the acidity of support during the selectivity hydrogenolysis of glycerol over supported bimetallic palladium–ruthenium (PdRu) catalysts. The PdRu nanoparticles were supported on a series of metal oxides and zeolitic supports via the modified impregnation method and tested for the liquid-phase hydrogenolysis of glycerol using gaseous hydrogen. The relative acid site densities of selected catalysts were determined by ammonia temperature-programmed desorption and pyridine desorption experiments. Based on these studies, we report a direct correlation between the catalytic activity (conversion and 1,2 propane diol yield) and two different acid sites (strong acid sites and very strong acid sites). Besides zeolite-supported catalysts, TiO 2 supported PdRu nanoparticles exhibit moderate catalytic activity; however, this catalyst shows high selectivity for the desired C–O bond cleavage to produce C3 products over the undesired C–C bond cleavage to produce < C3 products. This article is part of a discussion meeting issue ‘Science to enable the circular economy’.

Catalytic Pyrolysis of Shenhua Coal to Prepare Fuel Gases Using Metallic Oxide Supported Catalysts

2012 ◽  
Vol 443-444 ◽  
pp. 1084-1090
Author(s):  
Zhan Ying Guo ◽  
Rong Ran ◽  
Xin Qian Shu ◽  
Ying Ying Yuan ◽  
Yue Zhang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
High Temperature ◽  
Catalytic Pyrolysis ◽  
Supported Catalysts ◽  
Positive Influence ◽  
Metallic Oxide ◽  
Medium Temperature ◽  
Strong Adsorption ◽  
Series Of Experiments ◽  
The Individual

In order to study the catalytic activity in the preparation of fuel gases from catalytic pyrolysis of coal, the author selects NixOy/γ-Al2O3、CrxOy/γ-Al2O3，AgxOy/γ-Al2O3 and CoxOy/γ-Al2O3, respectively as the metal oxide supported catalysts from the previous experiment’s results. These catalysts have been added to Shenhua coal for a series of experiments. After these experiments, GC (gas chromatography) has been used for the analysis on the yield changes of CO and CH4 which result from the experiments. The results show that all of these catalysts have a positive influence on the yield of CO and CH4. As to the yield of CO, catalytic activity of CrxOy/γ-Al2O3 represents the most prominent performance at medium temperature period and CoxOy/γ-Al2O3 represents the same performance at high temperature period, while NixOy/γ-Al2O3, in which a great number of aluminum acid nickel spinels are reduced into metallic Ni at high temperature period, which results in different catalytic activity center from raw metallic Ni reduced from NiO. Consequently, the former reduced Ni shows outstanding catalytic activity. As to the yield of CH4, four catalysts mentioned above represent either the similar catalytic activity with CO or the individual characteristic —on one hand ,due to the strong adsorption of AgO and CrO3, CH4 gas is changed into H2 via pyrolysis at medium temperature as the yield of CH4 slumps ,on the other hand, due to an enormous amount of H2 production ,there is a drastically chemical reaction between H2 and these catalysts at high temperature, in which the yield of CH4 upswings toward the maximum amount greatly at the same time. Therefore, CrxOy/γ-Al2O3, AgxOy/γ-Al2O3 and CoxOy/γ-Al2O3 are more efficient at medium temperature and high temperature respectively. However, NixOy/γ-Al2O3 demonstrates the positive influence only from 800°Con. All of these results depend on the essence of catalysts to some extent. The study would have some theoretical guidance about increasing the utilization of coal and about industrial application of fuel gases generated from catalytic pyrolysis of coal.

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