Stability and inter-conversion of synthetic dawsonites in aqueous media

Ammonium aluminium carbonate hydroxide NH4Al(OH)2CO3 as an alternative route for alumina preparation: Comparison with the classical boehmite precursor

“…However, we also observed that excessive washing (V washing /V suspension > 1.6) could lead to a progressive formation of boehmite phase, while crystallized AACH was disappearing. This was consistent with the findings of Stoica et al [20] about the highly reactive nature of AACH in deionized water. In our case, such a transformation was possible because of the poor filterability of AACH suspension and therefore the long time during which the cake was exposed to water.…”

“…We observed in the literature that AACH is generally compared to boehmite from a textural point of view exclusively. However, since these two precursors can exhibit a different behaviour due to their particular properties [20], their preparation steps cannot be considered as being equivalent. Synthesis of pure AACH or boehmite thus requires certain specificities that need to be taken into account to compare the interest of both precursors from a more global perspective.…”

Bioinspired Synthesis of Monolithic and Layered Aerogels

“…To demonstrate that the new APD approach is applicable to a broad range of aerogel compositions, we have also produced an alumina‐based aerogel (dawsonite—sodium aluminum carbonate hydroxide) by the same method, as shown in Figure h. XRD and FTIR (see the Supporting Information) are consistent with NaAlCO 3 (OH) 2, dawsonite . Nitrogen adsorption–desorption isotherms show that these dawsonite aerogels have a mesoporous structure with a surface area of 345 m 2 g −1 and an average pore diameter of 5.7 nm.…”

Uncertainties of geochemical modeling during CO2 sequestration applying batch equilibrium calculations

“…While performing the required experiments, the kinetically limited precipitation of secondary minerals has to be regarded (Fu et al 2009;Zhu and Lu 2009). Studies pointing to the evaluation of dawsonite stability under specific conditions as in Stoica and Pérez-Ramírez (2010) or Coelha (2010) can help to answer open questions. When performing geochemical model calculations, we, therefore, recommend conducting scenario calculations varying the thermodynamic database and the secondary mineral assemblage.…”

“…However, to our knowledge, dawsonite production has not been identified in laboratory experiments under CCS reservoir conditions so far (See for example Kaszuba et al 2005). Furthermore, Stoica and Pérez-Ramírez (2010) pointed out that, among other things, a low pH value, as is found in CCS reservoirs, reduces the stability of dawsonite. Using K-feldspar as the starting material for reactions, products identified were kaolinite, illite, and boehmite (Bertier et al 2006;Shiraki and Dunn 2000;Fu et al 2009).…”