Abstract
The recycling of depleted high global warming mixtures of fluorinated gases (F-gases) with close-boiling or azeotropic behavior requires advanced separation processes to obtain effectively the pure components. Herein, several types of PIM-1 membranes were tested for the first time towards the separation of hydrofluorocarbons and hydrofluoroolefins, showing extraordinarily high permeability coefficients for the value-added difluoromethane (R-32), up to 4100 barrer, coupled with high selectivity for the F-gas pairs of interest. Additionally, the solubility of selected F-gases in PIM-1 was measured and fitted to the dual-mode and Guggenheim, Anderson and de Boer sorption models. The separation performance of the standard PIM-1 and a highly branched PIM-1 was examined with the mixture R-410A (containing R-32 and pentafluoroethane R-125) to assess the influence of the membrane topology on the mixed-gas permeation properties over time (physical aging). Considering that the branched PIM-1 membrane was the least impacted by the aging phenomena, it was used to recover high purity R-32 (concentration in the permeate side as high as 98.9 vol % was achieved) from refrigerant gas mixtures R-410A and R–454B (mixture of R-32 and R-1234yf) in continuous long-term experiments. Results showed the great potential of PIM-1 membranes for the separation of R-32 from refrigerant mixtures collected from end-of-life equipment.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.