Choline prolinate-based ionic liquid solvent blend for carbon capture: development and mini-pilot evaluation

This study investigates the ionic liquid blend choline-prolinate ([Cho][Pro]) utilized as a carbon-capture solvent at a mini-pilot (TRL 4) scale. The CO₂ absorption capacity was determined through laboratory measurements and validated under pilot-scale conditions. Data reconciliation was applied to pilot-plant measurements to ensure material-balance consistency. Key performance indicators, such as specific reboiler duty, solvent durability, viscosity, and emission behavior, were evaluated and benchmarked against 30 wt% monoethanolamine (MEA). The results demonstrated that the IL solvent exhibited competitive performance. Although minor loading-dependent chemical changes were observed, the solvent indicated a high resistance to gum formation. Emission analysis indicated low solvent compound concentrations across both streams, consistent with its low vapor pressure. These findings indicate that [Cho][Pro] can serve as an environmentally friendly alternative to the benchmark solvent, offering comparable energy performance while being known to be non-corrosive and non-toxic.