Sessile dissociation in the stoichiometric spinel MgAl2O4

Spinel (MgAl2O4) formation from stoichiometric MgO and Al2O3 is strongly mineralized by B-containing compounds such as boron oxide (B2O3), lithium tetraborate (Li2B4O7) and sodium tetraborate (Na2B4O7) at 1000°C. TEM confirms that the mineralization with each compound involves borate glass which is presumably formed on cooling from liquid at 1000°C. EDS shows the boron-containing liquids formed from B2O3 and Na2B4O7-mineralized samples contain little alumina suggesting a templated grain growth whereas those in Li2B4O7-mineralized samples dissolve sufficient alumina to suggest dissolution-precipitation is occurring at this temperature. XRD shows that Li2B4O7 is the most effective mineralizer producing single- phase spinel with 3 wt% addition at 1000°C whereas B2O3 produces Mg3B2O6 at 1.5 wt% addition and both B2O3 and Na2B4O7- mineralized samples show incomplete spinelisation which may be explained by the composition of the liquids formed with these two mineralizers.

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Geometry of {001} Surfaces of Spinel (MgAl2O4): First-Principles Simulations and Experimental Measurements

Journal of the American Ceramic Society ◽

10.1111/j.1551-2916.2005.00315.x ◽

2005 ◽

Vol 88 (6) ◽

pp. 1544-1548 ◽

Cited By ~ 27

Author(s):

N. J. van der Laag ◽

C. M. Fang ◽

G. de With ◽

G. A. de Wijs ◽

H. H. Brongersma

Keyword(s):

First Principles ◽

Experimental Measurements ◽

Spinel Mgal2o4

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Stoichiometry Defect at Grain Boundary Observed by Nano-Scale TEM Microanalysis in Spinel MgAl2O4

Advanced Engineering Materials ◽

10.1002/adem.200400083 ◽

2004 ◽

Vol 6 (10) ◽

pp. 822-825

Author(s):

N. Nuns ◽

F. Béclin ◽

J. Crampon

Keyword(s):

Grain Boundary ◽

Nano Scale ◽

Spinel Mgal2o4

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Ab initio simulation of the short-range order structure of Al ions and substitutional Fe, Cr impurities in S.S. Spinel (MgAl2O4)

International Journal of Quantum Chemistry ◽

10.1002/qua.20091 ◽

2004 ◽

Vol 100 (4) ◽

pp. 567-572 ◽

Cited By ~ 1

Author(s):

S. L. Votyakov ◽

A. V. Porotnikov ◽

Yu. V. Shchapova ◽

E. I. Yuryeva ◽

A. L. Ivanovskii

Keyword(s):

Ab Initio ◽

Short Range ◽

Short Range Order ◽

Range Order ◽

Order Structure ◽

Ab Initio Simulation ◽

Spinel Mgal2o4 ◽

Substitutional Fe

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Hydrogen Production from Methane Cracking in Dielectric Barrier Discharge Catalytic Plasma Reactor Using a Nanocatalyst

Energies ◽

10.3390/en13225921 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5921

Author(s):

Asif Hussain Khoja ◽

Abul Kalam Azad ◽

Faisal Saleem ◽

Bilal Alam Khan ◽

Salman Raza Naqvi ◽

...

Keyword(s):

Dielectric Barrier Discharge ◽

Barrier Discharge ◽

Plasma Reactor ◽

Dielectric Barrier ◽

X Ray ◽

Novel Approach ◽

Spinel Mgal2o4 ◽

The Stability ◽

Co Precipitation ◽

Methane Cracking

The study experimentally investigated a novel approach for producing hydrogen from methane cracking in dielectric barrier discharge catalytic plasma reactor using a nanocatalyst. Plasma-catalytic methane (CH4) cracking was undertaken in a dielectric barrier discharge (DBD) catalytic plasma reactor using Ni/MgAl2O4. The Ni/MgAl2O4 was synthesised through co-precipitation followed customised hydrothermal method. The physicochemical properties of the catalyst were examined using X-ray diffraction (XRD), scanning electron microscopy—energy dispersive X-ray spectrometry (SEM-EDX) and thermogravimetric analysis (TGA). The Ni/MgAl2O4 shows a porous structure spinel MgAl2O4 and thermal stability. In the catalytic-plasma methane cracking, the Ni/MgAl2O4 shows 80% of the maximum conversion of CH4 with H2 selectivity 75%. Furthermore, the stability of the catalyst was encouraging 16 h with CH4 conversion above 75%, and the selectivity of H2 was above 70%. This is attributed to the synergistic effect of the catalyst and plasma. The plasma-catalytic CH4 cracking is a promising technology for the simultaneous H2 and carbon nanotubes (CNTs) production for energy storage applications.

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