Nonaqueous Alkanolamine-Based Carbon Capture Systems: Modeling Alkanolamine/CO2/Organic Cosolvent Systems in s-SAFT-γ Mie

Abstract

Alkanolamine-based chemical absorption carbon capture may present a promising pathway to achieving much-needed CO2 emissions reductions, although high energy requirements pose a key challenge. A potential solution could be to replace water, the traditional alkanolamine cosolvent, with an organic (nonaqueous) alternative. To this end, this work presents the final step in parametrizing the s-SAFT-γ Mie predictive group-contribution equation of state (EoS) for alkanolamine/CO2/organic cosolvent systems. s-SAFT-γ Mie is extended to CO2/glyme and CO2/ethylene glycol mixtures and finally to alkanolamine/CO2/organic cosolvent systems. Using only a single parameter set, s-SAFT-γ Mie provides qualitatively meaningful predictions for a wide range of systems. This highlights the broad generalizability afforded by the group-contribution approach. While this generalizability comes at the cost of quantitative accuracy for individual systems, s-SAFT-γ Mie’s robust predictive capabilities and wide applicability render it suitable for potential use within an alkanolamine solvent/organic cosolvent screening tool.