Characterization and prediction of the CO2 effect on polymeric materials within the CO2 transport chain

Carbon capture and storage (CCS) is accepted by the international scientific community as the most viable short-term measure to limit CO2 emission in the atmosphere, avoiding reversible changes on the planet's climate. While CO2 capture and storage are of primary importance to allow a reduction of the carbon emission, viable and economically feasible CO2 transport solutions must be ensured to enable the CCS deployment. In particular, avoidance of leaks or failures within the entire transport chain is key to ensure that the effort of CO2 capture is not lost due to leakage during transportation. The transport of dense or liquid CO2 represents a challenge for many of the materials which come in contact with it. Particularly, polymeric materials may undergo temporary or permanent changes in structure when exposed to CO2 and this can affect their performance. However, there are still significant knowledge gaps in how polymer materials are affected by dense phase CO2. The CO2 EPOC project is closing these knowledge gaps by investigating the compatibility between polymeric materials and CO2 streams. This knowledge is being disseminated to enable more informed polymeric material selection within the CO2 transport chain. Two PhD candidates are nearing completion in the CO2 EPOC project: PhD1 at University of Oslo, Norway focusses on the compatibility of CO2 with polymer materials based on experimental work PhD2 at University of Bologna, Italy focusses on modelling of the interaction of CO2 with polymer materials A recent publication presented the sorption, diffusion, and permeation properties of various fluorinated thermoplastic polymers when exposed to high-pressure carbon dioxide. Furthermore, the obtained results are analyzed by a thermodynamic equation of state (EoS) model to describe the solubility behavior, while the standard transport model (STM) provides a reliable representation of gas transport through the polymers (https://doi.org/10.1021/acsapm.3c02056). Links to further published results from the CO2EPOC project, together with project newsletters are shared on the CO2 EPOC project website: https://www.sintef.no/en/projects/2020/co2-epoc/

Sustainable and efficient deployment of carbon capture and storage (CCS) requires suitable and reliable solutions at all levels of the value chain. Demonstrations of capture and storage technologies developed in the last decades have already realised a TRL able to support a quick CCS deployment, but knowledge gaps still exist regarding which polymer materials may be safely and effectively used in the CO2 transport infrastructure (e.g., elastomeric seals, gaskets, pipe liners etc as leakage seals and protective barriers). Transport of supercritical CO2 by pipeline or transport of cryo-compressed CO2 by ship create very different, but both highly demanding environments. These environments have different effects on polymeric materials, and can lead to transient and permanent changes in the materials (such as stiffening, cracking, seal leakage and premature part failure), resulting in re-emission of the CO2 during transport. The CO2-EPOC project aims to create knowledge on the compatibility between polymeric materials and CO2 streams to aid proper selection of polymer-based materials across the CO2 transport infrastructure (pipelines and ships) in order to avoid leakage and failure. Any losses during transport of the CO2 due to leakage greatly undermines the efforts spent on CO2 capture. The goal will be pursued by implementing a multilevel approach, spanning from experimental characterization of how representative polymers react to CO2 (including contaminants), to fundamental modelling to predict this behaviour in other application scenarios. Synergy between the levels will give improved understanding of the effect of CO2 on polymer materials, providing much needed knowledge for the design of efficient and reliable CO2 transport systems.