IMX Talks - Thermodynamic-kinetic modelling of precipitation processes

The understanding of solid formation from solution is an important topic in many fields of science and technology. It is a complex phenomenon result of convoluted elementary processes described by approximated equations, which are based on simplified theoretical frameworks. Despite these limitations, it is possible to tackle the problem by collecting accurate experimental data and applying models in order to identify a plausible and consistent pathway on the solid formation, with some prediction capabilities. Moreover, the some physical properties of the solid, such as the solid-liquid interfacial energy, can be estimated. The ultimate goal is that to influence the formation pathway in order to control the physicochemical properties of the product.
This exercise needs a multidisciplinary approach where analytical techniques, using ordinary laboratory apparatus or with the help of synchrotron light, are combined with computational tools. The coding needs to solve thermodynamic constraints on aqueous speciation, kinetics equations associated with the elementary processes, such as nucleation and growth, as well as mass balance equations associated with the particulate system, such as by means of the population balance approach.
In the talk, a possible strategy to study a precipitation process will be described, using the formation of calcium aluminate sulfates as case study, an important class of materials for the cement industry.
Bio: Andrea Testino, Senior Scientist at the Paul Scherrer Institut, is focusing his scientific interests on fundamental aspects of nanoparticles formation and characterization. The applied synthetic approaches are selected among those that allow collecting time-resolved experimental data and might be scaled to larger quantities. The investigation method has been applied for the preparation of nanomaterials as metals (such as Ni, Ag, Au, Pt), simple and complex metal oxides (such as Ce_xZr_(1-x)O₂, perovskites, spinels), doped-metal oxide (such as noble metal doped CeO₂), and sparingly soluble salts such as calcium carbonate, silicate, phosphate, and aluminum sulfate hydrate. The produced materials are used for several applied fields, from catalysis to biomedical devices.