CO2 Capture Using Fluorinated Hydrophobic Solvents

Finding more efficient gas-liquid scrubbing systems with lower parasitic energy penalties is important for the future deployment of carbon capture plants for large point source CO2 emitters. Minimization of the energy penalty using advanced solvents is one way to reduce the energy penalty. Nonaqueous, hydrophobic solvents are one type of solvent in which the physical properties of the solvent combined with low heats of absorption and low loading at high temperature even with high CO2 pressure result in promising solvents with low estimated reboiler heat duty. In this paper, a solvent composed of a hydrophobic amine (2-fluorophenethylamine) combined with an acidic, hydrophobic alcohol (octafluoropentanol) is studied mechanistically, and the experimentally determined reaction products, heats of absorption, and vapor liquid equilibria are reported. Approximating process models are compared and indicate the potential to lower reboiler heat duty in a commercial implementation.