Chemical Engineering Research & Design, Vol.105, 16-23, 2016
Solubility and diffusivity of carbon dioxide in perfluoropolyethers
The main objective of this work was to obtain new data for equilibrium and transport properties in the absorption of carbon dioxide into liquid solvents not yet investigated to this purpose. To this end, an experimental setup for measuring gas solubility and diffusivity in non-volatile solvents was designed, realized, and tested by comparison with literature data for the methane/n-dodecane pair. The solubility of carbon dioxide, nitrogen and oxygen in two different perfluoropolyethers, Fomblin (R) M03 and Fomblin (R) Y04, was measured at different temperature ranging from 10 degrees C to 100 degrees C and for pressures up to 7 bar. The diffusivity of carbon dioxide in the solvents was measured at 25 degrees C and 50 degrees C, through a pressure decay method. The results obtained in terms of carbon dioxide solubility and selectivity over other gases are encouraging for the possible use of Fomblin (R) perfluoropolyethers for the absorption of carbon dioxide from flue gases of industrial plants, also due to the complete immiscibility with water of this solvents. New compounds with similar chemical structure are being developed and tested in order to maximize the performances of the absorption process. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Keywords:Gas solubility;Gas diffusivity;Perfluoropolyethers;Gas absorption;Carbon dioxide;Pressure decay