The Structure and Interactions of Species in Supersaturated Caustic Aluminate Solutions

✍ Scribed by Addai-Mensah, Jonas ;Li, Jun ;Prestidge, Clive A.

• Publisher: Curtin University of Technology
• Year: 2008
• Tongue: English
• Weight: 522 KB
• Volume: 10
• Category: Article
• ISSN: 0969-1855
• DOI: 10.1002/apj.5500100608

✦ Synopsis

Abstract

The influence of akali metal ions (Na^+^ and K^+^), hydrogen isotope (H and D) and temperature on apparent hydrodynamic molar volumes, structure and interactions of species in synthetic, supersaturated caustic aluminate solutions (Bayer liquors) has been investigated. A strong dependency of structure, size and species interactions (ion‐ion and ion‐solvent) on the three primary variables was revealed. Sodium and deuterium‐based liquors displayed higher viscosities, reflected in greater attractive interactions, higher activation energies and entropies of viscous flow, than potassium and hydrogen‐based liquors. The apparent, hydrodynamic molar volumes of the viscosity modifying species were larger in sodium and hydrogenated than in potassium and deuterated aluminate liquors, and decreased with increasing temperature. Ionic strength‐independent average molar mass of Al(III)‐containing species close to 100 g mol^1^ and corresponding to monomeric, tetrahydroxo aluminate (Al(OH)) species was observed.