Ammonium aluminium carbonate hydroxide NH 4 Al(OH) 2 CO 3 as an alternative route for alumina preparation: Comparison with the classical boehmite precursor

Autor: Didier Colson, François Puel, Robin Lafficher, Malika Boualleg, Fabien Salvatori, Mathieu Digne
Přispěvatelé: Laboratoire d'automatique et de génie des procédés (LAGEP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS), IFP Energies nouvelles (IFPEN), Laboratoire de Génie des Procédés et Matériaux - EA 4038 (LGPM), CentraleSupélec
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Powder Technology
Powder Technology, Elsevier, 2017, 320, pp.565-573. ⟨10.1016/j.powtec.2017.07.080⟩
ISSN: 0032-5910
DOI: 10.1016/j.powtec.2017.07.080⟩
Popis: International audience; Ammonium aluminium carbonate hydroxide NH 4 Al(OH) 2 CO 3 as an alternative route for alumina preparation: comparison with the classical boehmite precursor. Powder Technology, 320, 565-573, Abstract Ammonium aluminium carbonate hydroxide (AACH) is a promising alternative precursor for preparation of alumina with high purity and original textural properties. In this paper, both boehmite (classical alumina precursor) and AACH were precipitated in a stirred tank reactor with close process parameters. Preparation protocols were thus compared. Main differences between both protocols were pointed out (reactant molar ratio influence, alumina concentration, filtration / washing step). This study helps for the choice of the appropriate preparation route for alumina precursor synthesis. As-synthesized boehmite and AACH precursors were then calcined between 500 °C and 1000 °C. The textural properties of the corresponding aluminas were characterized. At 500 °C, AACH-derived alumina revealed to be particularly porous, with larger mean pore diameter (ca. 29 nm) than boehmite-derived alumina (ca.6 nm). Moreover, AACH-derived alumina exhibited a high surface area. However, a more accurate analysis revealed that this high specific surface area (407 m 2 .g-1) is mostly due to microporosity formation during the calcination step. At higher calcination temperature, boehmite and AACH-derived aluminas exhibited different behaviors against sintering. In particular, the latter showed an interesting ability to maintain a constant mean pore diameter, regardless of the calcination temperature.
Databáze: OpenAIRE