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followed by the formation of metastable phase, dehydroxylation of brucite-like layers and decomposition of carbonates resulting in formation of double mixed oxide and/or spinel (after further heating) [ 21 , 28 , 29 ]. Similar steps were observed

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CH 3 OH synthesis and shift reaction), CuO catalyst, and CuCr 2 O 4 spinel catalyst [ 30 , 31 , 38 , 40 , 48 , 51 , 53 – 60 ]. First, we consider the partially reduced forms of the SNM-1 catalyst. The reduction was performed by

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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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-2261) in the solids Mn–Ce(Na) 100–0 and 50–50. In the solids Mn–Ce(Na) 50–50 and 0–100, the XRD patterns confirm the presence of CeO 2 (with fluorite-type structure JCPDS # 43-1002). In the samples Mn–Ce(Na)Cu 100–0, the presence of spinel Cu (JCPDS # 70

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