Aqueous precipitation and crystallization for the production of particulate solids with desired properties

It is the scope of this paper to review and apply the theory of crystallization kinetics to the analysis and design of aqueous inorganic hydrometallurgical precipitation systems. In particular the critical role of supersaturation in controlling the properties (crystallinity–stability, particle size and cleanliness) of the precipitated compounds is emphasized. The approach taken is of generic nature and not system-specific; however, reference is made to particular precipitation systems such as production of very fine monodispersed particles, hydrolysis/neutralization of acidic ferric sulphate liquors, iron precipitation from zinc process solutions, immobilization of arsenic in the form of crystalline scorodite, and gypsum crystallization in waste water treatment. Reference to these systems is not made with the purpose of describing the respective processes but rather to reinforce the validity of the supersaturation-controlled approach to industrial inorganic precipitation processes.