Development of a monoethanolamine/n-butanol biphasic solution with tunable phase separation for CO2 absorption via combined experimental and computational study: Role of solvation environment, phase separation mechanism

•An energy-efficient MEA/n-butanol biphasic absorbent with tunable phase separation was developed.•The effect of solvation environment on phase separation behavior and absorption/desorption performance was analyzed.•The phase separation mechanism was explored by NMR analysis and MD simulations.•The tunable phase separation was related to the strong intermolecular interaction between amine products.