Effect of La, Ce, Y and B addition on thermal stability of unsupported alumina membranes

Mesoporous activated alumina layers deposited on FeCrAl metallic substrates by an in situ hydrothermal method

“…The phase transformation of activated ␥-Al 2 O 3 to stable ␣-Al 2 O 3 is also responsible for the decrease of both the surface area and the pore volume. The alumina prepared by a hydrothermal method have a much higher surface area (360.1 m 2 /g, sintered at 600 • C) than the samples synthesized by a sol-gel method (266.8 m 2 /g, 600 • C) [12], which indicates that the alumina by the former method is more activated than the traditionally sol-gel-derived alumina. The pore volume is also much larger than that of the sol-gel-derived alumina, which may be due to the cavities left behind after the organic additives (CTAB and TEA) in the mixture are removed by calcination.…”

Preparation and characterization of mesoporous Al-MCM-41 layers deposited on FeCrAl metallic foils by an in-situ hydrothermal method

“…Connected directly to the surface of the sample and accessible to the guest species such as N 2 molecules, the open pores are in favor of the loading of noble metal catalysts compared to the so-called dead pores. The sample exhibits a BET surface area as high as 757.0 m 2 /g, twice as large as that of hydrothermally synthesized alumina [11] and 3 times as that of traditional so-gel-derived alumina [13] . The pore volume of the sample (0.72 cm 3 /g) is also larger than those of hydrothermally prepared alimunia (0.54 cm 3 /g) and so-gel-derived alumina (0.28 cm 3 /g).…”

The Role of CeO2-Doping of γ-Al_2O_3 on its Structural and Superficial Area

“…The transition from γ-Al 2 O 3 to α-Al 2 O 3 leads to a considerable reduction of the surface area, causing a degeneration of the catalytic activity [3]. Thermal stability can be enhanced by retarding or delaying phase transitions and it has been shown that rare earth element, such as Ce, will not only retard the phase transformation from γ-Al 2 O 3 to α-Al 2 O 3 , but will also stabilizes the pore structure of alumina [4][5][6]. The oxygen storage properties of ceria play a key role in all catalytic applications [7].…”