Bridging chemistry and technology in hydrometallurgical processing: from phase equilibria to high-purity products at lab-pilot scale

Converting complex, multicomponent solutions into specification-grade products is one of the recurring problems in hydrometallurgy. Whatever the target compound or sector, the path from a raw electrolyte to a marketable product runs through the same stepwise process development, and the same underlying principles apply throughout. Combining thermodynamic modelling with experimental validation makes it possible to develop scalable inorganic processes across the energy, water treatment, recycling and specialty chemicals sectors.

This presentation walks through a typical workflow for developing and testing a hydrometallurgical process. Everything starts with a brine or leachate and its underlying chemistry. Besides the theoretical planning of the process, lab testing is essential, starting with bench-top tests, moving through large batch tests, and ending in continuous precipitation tests. Wherever possible, these tests are carried out with original brine. From the results, a transferable operating window is derived that scale-up decisions can be based on. The talk also covers the practical issues that often decide whether a process works, such as controlling crystal size, morphology and phase through seeding, or choosing the right sensors to monitor the process.

Examples from real pilot campaigns illustrate how the method affects product quality and scale-up confidence. Among them is the production of high-purity lithium carbonate from original brine, independently confirmed by five laboratories.