ABSTRACT
This chapter provides an overview of the hydrometallurgical processing of minerals and metals. The choice of the purification and concentration process is largely influenced by the type and quantities of impurities in the process solution and final purity target level in the resultant product. Chemical precipitation that includes hydroxide and sulphide precipitation is by far the most widely used process in the industry because of its simplicity, cost-effectiveness and ease of operation. Solvent extraction of metals is based on the use of an organic solution to extract metal ions from an aqueous solution. Ion exchange is a process applied in purification, concentration and decontamination of aqueous and other ion containing solutions using solid polymeric or mineralic ion exchangers. Adsorption is a natural process by which molecules of a dissolved compound collect on and adhere to the surface of a solid material. Biosorption is based on binding capacities of various biological materials such as living or dead microorganisms or plants.
