Catalytic Decomposition of Methane: Effect of Various Factors on Catalytic Properties

2007 ◽  
Vol 544-545 ◽  
pp. 23-26 ◽  
Author(s):  
Hyun Chang Shin ◽  
Hyun Jung Kim ◽  
Dong Shin Yun ◽  
Jung Whan Yoo ◽  
Dong Jin Lee ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Reaction Temperature ◽  
Methane Conversion ◽  
Catalytic Properties ◽  
Catalytic Decomposition ◽  
Good Catalytic Activity ◽  
Decomposition Of Methane ◽  
Mesoporous Supports ◽  
Mcm 41

The effect of various reaction factors such as amount of Ni loaded, temperature, and variety of supports on the methane conversion were investigated to obtain higher methane conversion. The high activities were observed over Ni(10 wt%)/SiO2 catalyst and at 650oC of reaction temperature. Catalysts using mesoporous supports such as SiO2 and MCM-41 showed good catalytic activity and stability.

Alkylation of Benzene with Propylene over H3PW12O40 Supported on MCM-41 and -48 Type Mesoporous Materials

2010 ◽  
Vol 132 ◽  
pp. 192-204 ◽  
Author(s):  
M. Gómez-Ruiz ◽  
José Aarón Melo-Banda ◽  
C.E. Ramos Galván ◽  
S.E. López ◽  
R.R. Silva ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Mesoporous Materials ◽  
Reaction Temperature ◽  
Main Product ◽  
Catalytic Properties ◽  
Temperature Phase ◽  
Reaction Parameters ◽  
Phase Type ◽  
Alkylation Of Benzene ◽  
Mcm 41

The present work, the HPA Keggin structure was supported on four different MCM phase types (hexagonal, spherical, elliptical, and cubic); their catalytic properties were tested in the alkylation of benzene with propylene in order to produce cumene. In the reaction, parameters like propylene flow, reaction temperature, phase type, as well as WHSV-1, HPA, and Cs content in the best MCM phase support were studied. The results showed that the MCM-48 with (30 wt. % HPA) catalyst had the best behavior in catalytic activity, showing the higher conversion and selectivity toward cumene as the main product.

scholarly journals Transformation of 2-Butene into Propene on WO3/MCM-48: Metathesis and Isomerization of n-Butene

Catalysts ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 585 ◽  
Author(s):  
Derun Hua ◽  
Zheng Zhou ◽  
Qianqian Hua ◽  
Jian Li ◽  
Xinning Lu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
High Temperatures ◽  
Thermodynamic Analysis ◽  
Reaction Temperature ◽  
Thermodynamic Calculations ◽  
Metathesis Reaction ◽  
Good Catalytic Activity

The metathesis of 2-butene (Trans and Cis) to propene was investigated over W-based catalysts. Thermodynamic calculations for metathesis and isomerization were carried out at various temperatures to test the reactions. The results showed that the WO3/MCM-48 catalyst had good catalytic activity. The metathesis activity depended on the acidity of the catalyst and the dispersity of the WO3 on the supports. High temperatures promoted the isomerization of 2-butene to 1-butene. According to thermodynamic analysis, however, this is adverse to the metathesis reaction, making it important to determine an appropriate reaction temperature.

Catalytic Decomposition of Methane: Effect of Various Factors on Catalytic Properties

2007 ◽  
pp. 23-26
Author(s):  
Hyun Chang Shin ◽  
Hyun Jung Kim ◽  
Dong Shin Yun ◽  
Jung Whan Yoo ◽  
Dong Jin Lee ◽  
...  
Keyword(s):  
Catalytic Properties ◽  
Catalytic Decomposition ◽  
Decomposition Of Methane

Stability and catalytic properties of μ-oxo and μ-nitrido dimeric iron tetrasulfophthalocyanines in the oxidation of Orange II by tert-butylhydroperoxide

2014 ◽  
Vol 18 (07) ◽  
pp. 604-613 ◽  
Author(s):  
Anna S. Makarova ◽  
Evgeny V. Kudrik ◽  
Sergei V. Makarov ◽  
Oskar I. Koifman
Keyword(s):  
Catalytic Activity ◽  
Aqueous Solutions ◽  
Catalytic Oxidation ◽  
Organic Compounds ◽  
High Stability ◽  
Catalytic Properties ◽  
Orange Ii ◽  
Tert Butylhydroperoxide ◽  
Good Catalytic Activity ◽  
Very High

A study of catalytic activity of μ-nitrido- and μ-oxo-dimeric iron tetrasulfophthalocyanines in the oxidation of Orange II by tert-butylhydroperoxide in aqueous solutions has been performed. It is shown that though in one catalytic cycle activity of μ-oxo-dimer is higher, stability of this complex in oxidative conditions is poor. μ-nitrido-dimer combines relatively good catalytic activity with very high stability in the presence of tert-butylhydroperoxide. The mechanisms of oxidative decomposition of dimers and catalytic oxidation of Orange II have been proposed on the base of kinetic results. The products of catalytic processes are shown to be bio-degradable non-toxic small organic compounds.

Effect of Ag-doping of nanosized FeMgO system on its structural, surface, spectral, and catalytic properties

2012 ◽  
Vol 66 (8) ◽  
Author(s):  
Sahar El-Molla ◽  
Laila Ali ◽  
Nabil Amin ◽  
Anwer Ebrahim ◽  
Hala Mahmoud
Keyword(s):  
Catalytic Activity ◽  
Catalytic Properties ◽  
Textural Properties ◽  
Catalytic Decomposition ◽  
Molar Ratio ◽  
Paramagnetic Species ◽  
Ag Doping ◽  
H2o2 Decomposition ◽  
Physico Chemical ◽  
Structural Surface

AbstractThe effects of Ag-doping on the physico-chemical, spectral, surface, and catalytic properties of the FeMgO system with various Fe2O3 loadings were investigated. The dopant (Ag) molar ratio varied between 0.01 % and 0.05 %. The techniques employed for characterisation of catalysts were TG/DTG, XRD, ESR, N2 adsorption at −196°C, and catalytic decomposition of H2O2 at 25–35°C. The results obtained revealed that the investigated catalysts consisted of nanosized MgO as the major phase, apart from the MgFe2O4 and/or Fe3O4 phases. ESR result of the FeMgO system revealed the presence of paramagnetic species as a result of Ag-doping. The textural properties including SBET, porosity and St were modified by Ag-doping. The doping process with Ag-species improved the catalytic activity of the FeMgO system. Increasing the calcination temperature from 400°C to 800°C increased the catalytic activity (k*30 °C) of 0.05 AgFeMgO in H2O2 decomposition by 21.2 times.

Methane decomposition over unsupported mesoporous nickel ferrites: effect of reaction temperature on the catalytic activity and properties of the produced nanocarbon

RSC Advances ◽  
2016 ◽  
Vol 6 (72) ◽  
pp. 68081-68091 ◽  
Author(s):  
Manoj Pudukudy ◽  
Zahira Yaakob ◽  
Mohd Sobri Takriff
Keyword(s):  
Catalytic Activity ◽  
Reaction Temperature ◽  
Methane Decomposition ◽  
Precipitation Method ◽  
Decomposition Of Methane ◽  
Thermocatalytic Decomposition ◽  
Co Precipitation

Unsupported mesoporous nickel ferrites were successfully synthesized via a facile co-precipitation method and used for the thermocatalytic decomposition of methane into hydrogen and nanocarbon at various reaction temperatures.

scholarly journals Decomposition of methane into carbon and hydrogen over Ni-Li/CaO catalysts

2018 ◽  
Author(s):  
◽  
Ronald Wafula Musamali
Keyword(s):  
Fuel Cells ◽  
Hydrogen Production ◽  
Steam Reforming ◽  
Methane Conversion ◽  
Catalytic Decomposition ◽  
Lithium Hydroxide ◽  
Methane Decomposition ◽  
Hydrogen Yield ◽  
Carbon Fibres ◽  
Decomposition Of Methane

Overdependence on fossil-based fuels and their effect on environment is a global concern by energy stake holders. Bulk of present day hydrogen comes from gasification of coal, steam reforming and partial oxidation of hydrocarbons. Steam reforming accounts for over 50% of world hydrogen production despite producing carbonaceous gases which are harmful to the environment and poisonous to both; proton exchange fuel cells and alkaline fuel cells. Natural gas is a preferred feed for hydrogen production, because it is abundantly available on earth. Catalytic decomposition of ammonia can produce clean hydrogen but ammonia itself is an air pollutant. Catalytic decomposition of methane into carbon and hydrogen is an attractive option to producing clean hydrogen because its products are carbon and hydrogen. In this work, five different catalysts comprising of varying quantities of nickel and lithium, supported on calcium oxide were synthesized by incipient wetness impregnation method and designated according to weight % as; 30%Ni/CaO, 37.5%Ni-12.5%Li/CaO, 25.0%Ni- 25.0%Li/CaO, 12.5%Ni-37.5%Li/CaO and 50%Li/CaO. The synthesized catalysts were characterized by (XRD, SEM, BET and TEM) and tested for methane decomposition. From the XRD patterns of the synthesized catalysts, distinct crystalline phases of CaO and NiO were positively identified in 50%Ni/CaO according to their reference JCPDS files. Introduction of Lithium hydroxides improved the crystalline structure of the Ni/CaO catalyst. SEM analyses of the catalyst material using Image-J software confirmed that all catalyst materials were nanoparticles ranging from 3.09-6.56nm. BET results confirmed that, all the catalysts are mesoporous with pore sizes ranging from 20.1nm to 45.3nm. Introduction of LiOH to Ni/CaO generates mesoporous structures by destructing the lattices of the CaO structure during the formation of Ni-Li/CaO species. Particle size distribution in TEM analyses revealed that, a higher nickel loading in the catalyst favours the formation of carbon nanotubes while higher lithium hydroxide loading favours the formation of carbon fibres (CF). Low yield of carbon fibres from methane decomposition on unsupported Ni catalyst in 50%Ni/CaO was attributed to the presence of large Ni particles with low index planes which were incapable of dissociating the unreactive methane molecule. The aim of this work was to synthesize a catalyst for use in decomposition of methane into carbon and hydrogen, that addresses drawbacks of traditional solid metal catalysts such as sintering and coking. From the experimental results, 37.5%Ni-12.5%Li/CaO catalyst recorded 65.7% methane conversion and 38.3%hydrogen yield while 50%Ni/CaO recorded the lowest methane conversion of 60.2% and a hydrogen yield of 35.7% at 650℃. Outstanding performance of the 37.5%Ni-12.5%Li/CaO catalyst is attributed to the incorporation of lithium hydroxide which provided more catalyst active sites and a molten environment for proper dispersion of the nickel metal. The solid 50%Ni/CaO catalyst readily deactivated due to coking unlike the supported molten 37.5%Ni-12.5%Li/CaO catalyst in which methane decomposition reaction took place by both surface reaction and chemisorption.

Catalytic Synthesis of Dioctyl Phthalate over Al-MCM-41 Molecular Sieves

2011 ◽  
Vol 306-307 ◽  
pp. 1741-1746
Author(s):  
Hua Feng Zhou ◽  
Yong Jin Yang ◽  
Jin Son Zhang
Keyword(s):  
Catalytic Activity ◽  
Molecular Sieves ◽  
Hydrothermal Process ◽  
Analytical Techniques ◽  
Catalytic Performance ◽  
Dioctyl Phthalate ◽  
Catalytic Synthesis ◽  
Al Content ◽  
Good Catalytic Activity ◽  
Mcm 41

In this paper, mesoporous MCM-41 and Al-MCM-41(Si/Al =100, 70, 40, 10, 5) molecular sieves were synthesized by direct hydrothermal process and characterized by various analytical techniques. Their catalytic performance in the synthesis of dioctyl phthalate (DOP) was also studied. The results show that while keeping the mesostructure of Al-MCM-41(Si/Al=100, 70, 40), increasing Al content can increase the acidity and so forth effectively improve the catalytic activity. But too much aluminum incorporation can destroy the structure of Al-MCM-41(Si/Al=10). The Al-MCM-41 molecular sieves with proper Si/Al ratios have good catalytic activity and stability in DOP synthesis. When Al-MCM-41(40) was used as the catalyst, A high PA conversion of 98.45% can be reached in 4 h. After being reused for five times, Al-MCM-41(40) still remains good catalytic activity.

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