Bridging molecular modeling and 3E cycle analysis in absorption cooling using biomass-based solvents

Improving the sustainability of thermal processes has fostered growing interest in renewable, biodegradable, and non–toxic compounds. Among them, biomass–derived solvents present significant advantages over traditional petroleum–based alternatives, contributing to circular economy strategies. In this study, we develop a comprehensive thermodynamic framework to assess the potential of new refrigerant–solvent working pairs for absorption refrigeration systems (ARS). These pairs combine fluorinated refrigerants and CO 2 with five green organic solvents: Propylene Carbonate, Solketal, Terpinolene, γ –Valerolactone, and Rhodiasolv PolarClean. The solubility of refrigerants in these solvents is modeled using an extended version of the SAFT–VR Mie equation of state, incorporating descriptors for planar ring structures and polar contributions. Refrigerants are treated as non–associating but dipolar fluids, and their thermophysical properties are successfully reproduced. Mixture behavior is captured with a single, temperature–independent binary interaction parameter, enabling reliable extrapolation to process conditions. The validated model is employed to quantify the working capacity of each refrigerant–solvent pair, serving as a pre–screening tool to choose the most promising pairs for cycle simulation. Single–effect (SE) and compression–assisted (CA) ARSs are evaluated through a detailed parametric study. Then, a comprehensive 3E analysis (energetic, exergetic, and environmental) is conducted, incorporating Key Performance Indicators, including the energy and exergy coefficients of performance, circulation ratio, high–pressure levels, and the total equivalent warming impact (TEWI). Finally, the TOPSIS multi–criteria decision–making method is applied to rank the working pairs and identify the best options for each configuration, revealing that R32/ γ –Valerolactone stands out as the best working pair in CA–Cycles when environmental concerns are considered. • Biomass-derived solvents with F-gases and CO 2 assessed as new working pairs. • SAFT-VR Mie models account for association, polarity and ring formation. • γ -Valerolactone and Rhodiasolv Polarclean show the highest working capacity. • TEWI analysis confirms the dominant role of indirect emissions in CA-ARS. • TOPSIS ranking identifies R32/ γ -Valerolactone as optimal CA working pair.