Role of boehmite/solution interface in boehmite precipitation from supersaturated sodium aluminate solutions

This work presents the developments made in the Laboratory of Metallurgy of the National Technical University of Athens in the field of boehmite precipitation from supersaturated sodium aluminate solutions under atmospheric conditions. Initially, the boehmite process is described by giving emphasis to kinetic problems that reduce the process efficiency and make it less attractive. Moreover, it is demonstrated that the physicochemical properties of the boehmite/solution interface are of great importance for the understanding of the boehmite precipitation mechanism. Therefore, the physicochemical properties of the boehmite/solution interface are theoretically determined giving emphasis to the surface speciation diagrams and the surface potential that are presented as a function of pH and the boehmite seed concentration in the solution. Finally, the theoretical data are correlated to the mechanism of boehmite precipitation and utilized for the understanding of alternative precipitation methods that improve the process efficiency. (C) 2004 Elsevier B.V. All rights reserved.