This project will tackle one of the key technical challenges facing the development of commercially viable CO2 transport networks: modelling the phase behaviour of impure carbon dioxide, under the conditions typically found in carbon capture from power stations, and in high-pressure (liquid phase) and low-pressure (gas phase) pipelines. Models for phase behaviour are known as equations of state (EoS). EoS vary in their mathematical form, accuracy, region of validity and computational complexity. Because different applications have different requirements, there is no single EoS that is ideal for all applications. This project will use cutting-edge computer algorithms to automatically reparameterise EoS for CCS modelling. This flexible technique will allow a user to specify their requirements and re-derive model parameters matched to their needs. Our algorithms will directly produce functional forms for EoS from experimental data, thus fully automating the derivation of EoS. This will enable users to rapidly produce bespoke EoS that are tailored to their particular application, and will enable these models to continually evolve as new measurements become available, ensuring that experimental advances are rapidly converted into improved CCS modelling and, ultimately, better performance and efficiency of real CCS processes. Grant number: UKCCSRC-C1-22.