Thermodynamic-Kinetic Reverse Optimization for CO2 Capture Absorbents

Abstract The conventional trial-and-error paradigm for developing amine-based absorbents is inherently limited in simultaneously optimizing absorption capacity, reaction kinetics, and regeneration energy for industrial CO2 capture under low partial-pressure conditions. Here, we present an inverse-design framework based on intrinsic thermodynamic and kinetic parameters. A coupled thermodynamic-kinetic model was established to describe CO2 absorption, and the enthalpy–entropy compensation relation was introduced, thereby establishing a theoretical correlation between the variations of the thermodynamic-kinetic parameters and the absorption performance indicators. A total of 10,000 parameter combinations were generated using Latin hypercube sampling, and the absorption behavior was systematically investigated over temperatures of 298.15–313.15 K and CO2 partial pressures of 0.03–0.30 bar through global Sobol sensitivity analysis. A capacity–time performance metric was further introduced to identify optimal parameter windows that simultaneously balance absorption performance and regeneration energy under different operating conditions. Case analysis of three representative absorbents–diethylamine/poly(ethylene glycol)-200 (DEA/PEG200), 2-ethylaminoethanol (2EAE), and monoethanolamine (MEA)–revealed distinct thermodynamic-kinetic performance signatures, demonstrating that the proposed framework can diagnose the dominant performance limitation and provide operating-condition-specific directions for absorbent optimization. This study establishes a parameter-driven inverse screening strategy for absorbent development, providing a theoretical basis for the efficient screening of liquid absorbents and their application-oriented optimization under industrially relevant temperature and CO2 partial-pressure conditions.