Research progress in theory and technology of gibbsite precipitation from sodium aluminate solution

The precipitation of sodium aluminate solution is the key process for alumina refinery by alkaline method.The research progress in theory and technology of the precipitation process was summarized.Five important aspects,including the thermodynamics and macrokinetics,aluminium-bearing species present in the aluminate solution and the species evolution,the behavior of aluminum trihydroxide particles,the interaction regulation of the interface between gibbsite particles and aluminate solution and the strengthening techniques for gibbsite precipitation,were discussed.It is held that the aluminate species favoring gibbsite precipitation is and thus the ways of converting other complex aluminate species to would increase the precipitation rate,and that the key of improving the precipitation rate is to increase the smallest particle size in the late period of precipitation.It is also held that it is the research fundamental of seeded precipitation to study the principle and method for coordinately regulating physicochemical properties of aluminate solution,ion structure and the interaction of the interface between gibbsite particle and aluminate solution.