Browsing by Subject "Calcination"

Article

A comparative study of the steam reforming of phenol towards H2 production over natural calcite, dolomite and olivine materials

Constantinou, D. A.; Fierro, José Luis García; Efstathiou, Angelos M. (2010)

Pre-calcined (air, 850 °C) naturally occurring calcite, dolomite and olivine materials were studied for phenol steam reforming towards H2 production. The effect of reaction temperature, feed volume flow rate, and hydrogen ...

Article

Deactivation of Pd/Ce 0.5Zr 0.5O 2 model three-way catalyst by P, Ca and Zn deposition

Christou, Stavroula Y.; García-Rodríguez, S.; Fierro, José Luis García; Efstathiou, Angelos M. (2012)

The negative effects of P, P-Ca and P-Zn deposition on the surface of a model 1wt% Pd/Ce 0.5Zr 0.5O 2 " three-way" catalyst (TWC) on its structural, morphological, textural, oxygen storage and release, and catalytic ...

Article

The effect of calcination temperature on the oxygen storage and release properties of CeO2 and Ce-Zr-O metal oxides modified by phosphorus incorporation

Larese, C.; López Granados, M.; Mariscal, R.; Fierro, José Luis García; Lambrou, Panayiota S.; Efstathiou, Angelos M. (2005)

The present work reports on the effects of calcination temperature (T c) on the oxygen storage and release properties of CeO2 and Ce0.8Zr0.2O2 solids deliberately contaminated with CePO4. Pulsed-feed and stepped-feed dynamic ...

Article

Effect of thermal aging on the transient kinetics of oxygen storage and release of commercial Cex Zr1-x O2-based solids

Christou, Stavroula Y.; Bradshaw, H.; Butler, C.; Darab, J.; Efstathiou, Angelos M. (2009)

The use of powerful analytical methodologies for the evaluation of the performance of commercial oxygen storage materials based on oxygen transient isothermal isotopic exchange experiments is illustrated in this study. Ce ...

Article

Effects of calcination temperature on the stability of CePO4 detected in vehicle-aged commercial three-way catalysts

Larese, C.; Cabello Galisteo, F.; López Granados, M.; Mariscal López, R.; Fierro, José Luis García; Lambrou, Panayiota S.; Efstathiou, Angelos M. (2004)

Samples extracted from a vehicle-aged commercial TWC monolith (the inlet part of the first cartridge) have been shown to contain CePO4. The effects of calcination temperature in the 773-1173K range on these samples have ...

Article

The effects of P-poisoning of CexZr1-xO2 on the transient oxygen storage and release kinetics

Christou, Stavroula Y.; Efstathiou, Angelos M. (2013)

The present work reports on the investigation of the effects of chemical poisoning of CexZr1-xO2 solids by phosphorous (P) on the kinetics of oxygen storage and release (OSR) of the thus derived P-contaminated solids, as ...

Article

Hofmeister anion effects on surfactant self-assembly and the formation of mesoporous solids

Leontidis, Epameinondas (2002)

Recent work on mesoporous silica formation using cationic and non-ionic templates has unveiled a large number of anion effects. Anions are seen to change the hydrolysis rates of the silicate precursors, affecting the surface ...

Article

Investigation of the synthesis and properties of ternary V-Cu-Ce Oxides of Composition VxCuxCe1-2xO2

Attipa, Christothea; Theocharis, Charis R. (2009)

Aco-precipitation method has been used to prepare ternary mixed oxides based on ceria with the general formula VxCuxCe 1-2xO2, where x was varied between 0.05 and 0.45. The structural and surface properties as well as the ...

Article

Novel Zn-Ti-based mixed metal oxides for low-temperature adsorption of H2S from industrial gas streams

Polychronopoulou, Kyriaki; Fierro, José Luis García; Efstathiou, Angelos M. (2005)

The efficiency of various Zn-Ti-based mixed metal oxides prepared by the sol-gel method towards H2S adsorption from a gas mixture containing 0.06 vol.% H2S, 25 vol.% H2, 7.5 vol.% CO2 and 1 vol.% H2O was studied in the ...

Article

Organized silica films generated by evaporation-induced self-assembly as hosts for iron oxide nanoparticles

Andreou, Ioanna; Amenitsch, H.; Likodimos, Vlassis; Falaras, Polycarpos; Koutsoukos, Petros George; Leontidis, Epameinondas (2013)

In this work, we prepared oriented mesoporous thin films of silica on various solid substrates using the pluronic block copolymer P123 as a template. We attempted to insert guest iron oxide (FexOy) nanoparticles into these ...

Article

The phenol steam reforming reaction towards H2 production on natural calcite

Constantinou, D. A.; Fierro, José Luis García; Efstathiou, Angelos M. (2009)

The steam reforming of phenol towards H2 production was studied in the 650-800 °C range over a natural pre-calcined (air, 850 °C) calcite material. The effects of reaction temperature, water, hydrogen, and carbon dioxide ...

Article

The steam reforming of phenol over natural calcite materials

Constantinou, D. A.; Efstathiou, Angelos M. (2009)

Five natural calcite materials of different geographical origin were studied towards the steam reforming of phenol reaction and the activity results obtained were correlated with some of their physico-chemical properties. ...

Article

Suppression of the oxygen storage and release kinetics in Ce0.5Zr0.5O2 induced by P, Ca and Zn chemical poisoning

Christou, Stavroula Y.; Álvarez-Galván, M. C.; Fierro, José Luis García; Efstathiou, Angelos M. (2011)

The present investigation concerns for the first time the understanding of the individual and combined effects of phosphorous with calcium or zinc deposited on a Ce0.5Zr0.5O2 solid followed by calcination in 20%O2/He at ...

Article

Temperature programmed reduction of silica supported nickel catalysts

Afzal, M.; Theocharis, Charis R.; Karim, S. (1993)

Nickel oxide promoted catalysts are prepared by simple precipitation, precipitation from homogeneous solution and impregnation methods and their reduction behavior is monitored with temperature programmed reduction (TPR) ...