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.

Sol–gel synthesis of Ni and Ni supported catalysts for hydrogen production by methane decomposition

RSC Advances ◽  
2014 ◽  
Vol 4 (79) ◽  
pp. 42159-42167 ◽  
Author(s):  
Yi Shen ◽  
Aik Chong Lua
Keyword(s):  
Hydrogen Production ◽  
Supported Catalysts ◽  
Sol Gel ◽  
Methane Decomposition ◽  
Sol Gel Synthesis ◽  
Ni Supported Catalysts

Sol-gel synthesis of NiO and supported NiO catalysts for hydrogen production by methane decomposition.

scholarly journals Effect of Precipitated Precursor on the Catalytic Performance of Mesoporous Carbon Supported CuO-ZnO Catalysts

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 582
Author(s):  
Yandong Li ◽  
Guangfen Liang ◽  
Chengrui Wang ◽  
Yanhong Fang ◽  
Huamei Duan
Keyword(s):  
Electron Microscopy ◽  
Mesoporous Carbon ◽  
Catalyst Activity ◽  
Catalyst Support ◽  
Catalytic Performance ◽  
Chemical Energy ◽  
X Ray Diffraction ◽  
Methanol Production ◽  
Transmission Electron ◽  
Co Precipitation

As part of concepts for chemical energy storage of excess chemical energy produced from renewable sources, we investigated the performance of CuO/ZnO catalysts supported on mesoporous carbon to convert CO2 hydrogenation to methanol. In this work, mesoporous carbon was used as the catalyst support for CuO-ZnO catalysts. Four catalysts with different precipitated precursors were synthesized and analyzed by N2-physisorption, X-ray diffraction (XRD), thermogravimetric analysis (TG-DTG), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that catalyst CZ-in situ had the highest turnover frequency (TOF) (2.8 × 10−3 s−1) and methanol production rate (0.8 mmol g−1·h−1). The catalysts for co-precipitation of copper and zinc on carbon precursors are more active. Cu/ZnO domains that are accessible to the reactant gas are another reason for the catalysts being active. The Cu-ZnO interface is crucial to methanol catalyst activity.

Production of Hydrogen through Decomposition of Methane with Ni-supported Catalysts

1999 ◽  
Vol 28 (11) ◽  
pp. 1179-1180 ◽  
Author(s):  
Kiyoshi Otsuka ◽  
Takeshi Seino ◽  
Shoji Kobayashi ◽  
Sakae Takenaka
Keyword(s):  
Supported Catalysts ◽  
Production Of Hydrogen ◽  
Decomposition Of Methane ◽  
Ni Supported Catalysts

scholarly journals Ni-γ-AL2O3 catalysts for obtaining nanocarbon by decomposition of natural gas

2021 ◽  
Author(s):  
Hikmet Ibrahimov ◽  
Sara Malikli ◽  
Zenfira Ibrahimova ◽  
Rahim Babali ◽  
Sevinc Aleskerova
Keyword(s):  
Natural Gas ◽  
Specific Surface ◽  
Catalytic Converter ◽  
Sol Gel ◽  
Nickel Content ◽  
Maximum Yield ◽  
Methane Decomposition ◽  
Impregnation Method ◽  
Decomposition Of Methane ◽  
Gas Supply

Abstractγ-Al2O3 was synthesized by the Sol–gel method, Ni (NO3)2 was placed in the pores by the impregnation method, and Ni-γ-Al2O3 was obtained by pyrolysis in a hydrogen stream in a CVD device. By the method of chemical vapors phase deposition (CVD) on Ni-Al2O3 catalytic converter with decomposition of methane in the natural gas produced carbon nanotubes (CNT) (Chunduri et al. in Mater Express 4(3):235–241, 2014; Zhou et al. in Appl Catal B 208:44–59, 2017). The catalytic activity of the catalysts in methane decomposition was examined from 650 °C to 900 °C by the method of chemical vapors phase deposition (CVD), the yield of CNTs tends to increase with the growth at the ratio of natural gas supply to hydrogen. The specific surface increases with an increase of nickel content and can reach 265.5 m2/g for a sample of 2% Ni-A12O3 at 850 °C. Growth at the temperature of methane decomposition leads to reduction in its specific surface. It has been established that the use of the Ni-Cu/γ-Al2O3 catalytic system, in which copper acts as a stabilizing additive, makes it possible to double the maximum yield of the carbon product during the decomposition of natural gas.

scholarly journals Chemical Quantification of Atomic-Scale EDS Maps under Thin Specimen Conditions

2014 ◽  
Vol 20 (6) ◽  
pp. 1782-1790 ◽  
Author(s):  
Ping Lu ◽  
Eric Romero ◽  
Shinbuhm Lee ◽  
Judith L. MacManus-Driscoll ◽  
Quanxi Jia
Keyword(s):  
Atomic Scale ◽  
Specimen Thickness ◽  
Peak Width ◽  
Thin Specimen ◽  
Gaussian Peak ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
The Relationship ◽  
Chemical Quantification

AbstractWe report our effort to quantify atomic-scale chemical maps obtained by collecting energy-dispersive X-ray spectra (EDS) using scanning transmission electron microscopy (STEM) (STEM-EDS). With thin specimen conditions and localized EDS scattering potential, the X-ray counts from atomic columns can be properly counted by fitting Gaussian peaks at the atomic columns, and can then be used for site-by-site chemical quantification. The effects of specimen thickness and X-ray energy on the Gaussian peak width are investigated using SrTiO3 (STO) as a model specimen. The relationship between the peak width and spatial resolution of an EDS map is also studied. Furthermore, the method developed by this work is applied to study cation occupancy in a Sm-doped STO thin film and antiphase boundaries (APBs) present within the STO film. We find that Sm atoms occupy both Sr and Ti sites but preferably the Sr sites, and Sm atoms are relatively depleted at the APBs likely owing to the effect of strain.

Interfaces in Structural Ceramics

MRS Bulletin ◽  
1990 ◽  
Vol 15 (10) ◽  
pp. 51-59 ◽  
Author(s):  
M. Grant Norton ◽  
C. Barry Carter
Keyword(s):  
Structural Ceramics ◽  
Interface Engineering ◽  
Micro Structure ◽  
Complete Understanding ◽  
Intimate Contact ◽  
Transmission Electron ◽  
Processed Material ◽  
Wide Range ◽  
Alternative Materials ◽  
The Relationship

Structural ceramics are necessarily polycrystalline and their usefulness is largely determined by the interfaces between the grains. The relationship between the structure and chemistry of different interfaces and the micro-structure can be illustrated by reviewing studies of interfaces in a wide range of materials including such classical ceramics as Al2O3, the current “hightech” polyphase ceramics exemplified by ZrO2-toughened Al2O3, and the composite materials of the future. Using transmission electron microscopy is essential for a complete understanding, but limitations to its use must be recognized. Only by understanding the factors that control the behavior of these interfaces will it become possible to further extend the application of interface engineering.Structural ceramics are a group of materials that can be used for applications requiring their strength to persist at high temperatures or in conditions that would be particularly corrosive to alternative materials, which are usually metallic. Strength and strength-related properties such as toughness depend largely on the microstructural features of the processed material.The microstructure is defined by the morphology and size of the grains and the interfaces between these grains. If the grains are in intimate contact, then the interface is a grain boundary of the type familiar from studies of metals.

The relationship between emerging neural crest cells and basement membranes in the trunk of the mouse embryo: a TEM and immunocytochemical study

Development ◽  
1986 ◽  
Vol 98 (1) ◽  
pp. 251-268
Author(s):  
J. Sternberg ◽  
S. J. Kimber
Keyword(s):  
Neural Crest ◽  
Neural Tube ◽  
Cell Shape ◽  
Type Iv Collagen ◽  
Neural Crest Cell ◽  
Basement Membranes ◽  
Type Iv ◽  
Transmission Electron ◽  
The Relationship ◽  
Crest Cell

The earliest stage of neural crest cell (NCC) migration is characterized by an epitheliomesenchymal transformation, as the cells leave the neural tube. There is evidence that in a number of cell systems this transformation is accompanied by alteration or depletion of associated basement membranes. This study examines the ultrastructural relationship between mouse NCCs and adjacent basement membranes during the earliest stages of migration from the neural tube. Basement membranes were identified by transmission electron microscopy (TEM) and immunofluorescence using antibodies to type-IV collagen. The ultrastructural features of NCCs and their relationship with surrounding tissues were also examined using TEM. In the dorsal region of the neural tube, from which NCCs originate, the basement membrane was depleted or absent, and with the immunofluorescence technique it was shown that this pattern was reflected in a deficit of type-IV collagen. TEM observations indicated that ultrastructurally NCCs differ from their neuroepithelial neighbours only in overall cell shape and their relationship to other cells and the extracellular matrix.

Nickel Nanoparticles Supported on Diphenylphosphinated Poly(Vinyl Alcohol-Co-ethylene) as a New Heterogeneous and Recyclable Catalyst for Mizoroki–Heck Reactions

2017 ◽  
Vol 41 (9) ◽  
pp. 541-546 ◽  
Author(s):  
Farzaneh Ebrahimzadeh
Keyword(s):  
Vinyl Alcohol ◽  
Nickel Nanoparticles ◽  
Supported Catalysts ◽  
Low Cost ◽  
Poly Vinyl Alcohol ◽  
X Ray Diffraction ◽  
Heck Reactions ◽  
Modified Polymer ◽  
Transmission Electron ◽  
High Metal

Nickel nanoparticles (NiNPs) supported on diphenylphosphinated poly(vinyl alcohol- co-ethylene) (DPP-PVA- co-PE) were synthesised by first reacting poly(vinyl alcohol- co-ethylene) with chlorodiphenylphosphine (ClPPh2) under basic conditions and then treating the product with Ni(OAc)2 followed by reduction with NaBH4. (DPP-PVA- co-PE)-NiNPs, a new metallised polymer, was then shown to efficiently catalyse Mizoroki–Heck reactions of aryl iodides, bromides or activated chlorides with olefins such as styrene and n-butyl acrylate in dimethylformamide. In contrast with other polymer-supported catalysts, the main advantage of this method is the low cost of the catalyst due to the simple synthetic route using easily obtained materials and good recoverability. Transmission electron microscopy and X-ray diffraction measurements were used to show the high metal dispersion and small sizes of Ni nanoparticle on the surface of the modified polymer. DPP-PVA- co-PE-NiNPs could be recycled several times.

Sign in / Sign up

Export Citation Format

Share Document