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hydrocarbons [ 17 – 22 ] and unsaturated aldehydes [ 12 , 23 – 25 ], water–gas shift reaction [ 26 ], and many other processes [ 27 , 28 ] where the optimal carriers for platinum are a major issue. Magnesium aluminate spinel (MgAl 2 O 4 ) is a favorable

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Souhila Boumaza, Aline Auroux, Simona Bennici, Amel Boudjemaa, Mohamed Trari, Aissa Bouguelia, and Rabah Bouarab

Abstract  

Cu-based mixed oxides were prepared by a co-precipitation method and characterized by XRD analysis, BET and H2-TPR. For all catalytic systems, it was found by XRD analysis that the spinel phase is the majority phase. Catalysts were tested for the production of hydrogen via the water gas shift reaction between 150 and 250 °C. It was demonstrated by TPR that Cu–Zn–Al and Cu–Al were easily reduced. This may be responsible for relatively high catalytic activity in comparison with the results obtained by Cu–Co and Zn–Al catalysts prepared by the same method. The oxide systems can be ranked as follows: Cu–Zn–Al > Cu–Al > Cu–Mn, Cu–Cr > Cu–Fe ≫ Zn–Al > Cu–Co at 250 °C.

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Reaction Kinetics, Mechanisms and Catalysis
Authors: R. Thinesh Kumar, N. Clament Sagaya Selvam, T. Adinaveen, L. John Kennedy, and J. Judith Vijaya

Introduction Nanostructured metal aluminate spinels constitute an interesting class of oxide ceramics with important technological applications such as lower temperature sinterability, greater thermal stability, increased

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Introduction Ferrite spinels are important catalysts for various chemical reactions like the water gas shift reaction, carbon monoxide (CO) oxidation, alkylation reactions etc. [ 1 – 3 ] due to their structural and redox

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obtained ((NH 4 )[Fe 2 Cu(C 4 H 4 O 6 ) 2 (OH) 5 ]·9H 2 O) was submitted to thermal treatment, 800 °C for 2 h in order to obtain well crystallized copper spinel. The specific surface and the pore size distribution of the samples were determined from

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Viorel Chihaia, Karl Sohlberg, B. Grzybowska-Świerkosz, M. Ruszel, R. Grabowski, L. Kępiński, M. A. Małecka, and J. Sobczak

objects of fundamental studies: the supports possess the same spinel structure and similar specific surface area; they differ, however, depending on cation M II , in physicochemical properties, in particular, reducibility. A correlation between the

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Viorel Chihaia, Karl Sohlberg, Margarita Gabrovska, Rumeana Edreva-Kardjieva, Dorel Crişan, Peter Tzvetkov, Maya Shopska, and Iskra Shtereva

-stoichiometric Ni–Al spinel-like phase, which may be hypothesized to be located at the interface between NiO and the alumina-type phase and Phase III: an alumina-type phase doped with small amounts of Ni 2+ ions, probably ‘grafted’ on the spinel-like phase. The

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Viorel Chihaia, Karl Sohlberg, Monica Dan, Maria Mihet, Alexandru R. Biris, Petru Marginean, Valer Almasan, George Borodi, Fumiya Watanabe, Alexandru S. Biris, and Mihaela D. Lazar

TPR pattern indicated the possible presence of non-stoichiometric Ni–Al spinel on catalyst surface, but in the XRD patterns, it was hard to distinguish this from γ-Al 2 O 3 due to their similar morphology and characteristic peaks. For all samples, the

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.5 Spinel Pure NiFe 2 O 4 7.7 Spinel ca. 3 % Fe 2 O 3 (hematite

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Yunfeng Hu, Jinpeng Cao, Jun Deng, Baoyu Cui, Mingwei Tan, Junfei Li, and Hongsheng Zhang

], the formation of the spinel CuAl 2 O 4 is easy at lower copper loading. The presence of CuO bulk phase in samples can be rather easily detected, but this is not the case for CuAl 2 O 4 which also has spinel type structures and their diffractograms

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