Improved carbon dioxide stripping by membrane contactors using hydrophobic electrospun poly(vinylidene fluoride-co-hexafluoro propylene) (PVDF-HFP) membranes

Electrospun poly(vinylidene fluoride-co-hexafluoro propylene) (PVDF-HFP) nanofibre membranes are developed for CO2 stripping within a membrane contactor. The porous and hydrophobic nature of the membranes is ideal for membrane CO2 stripping applications, providing fast gas transport, high CO2 recovery and mechanical strength. Three different morphologies of the PVDF-HFP membranes are assessed: nanofibre membranes (NFM), bead-on-string membranes (NFM-BS) and microparticles on nanofibre membranes (NFM-MP). We illustrate that both the bead-on-string and microparticles on nanofibre membranes are more hydrophobic compared to nanofibre constructs and a traditional asymmetric control membrane. The NFM-BS and NFM-MP membranes both exhibit significantly improved CO2 stripping flux over short times, while the NFM-BS membranes provides significantly improved stripping flux over longer times (240 h) compared to all other treatments, including conventional asymmetric phase inversion membranes. The structures may also show promise for membrane distillation applications.

Automated summary

Electrospun PVDF-HFP nanofibre membranes exhibit excellent performance for CO2 stripping, with improved hydrophobicity and CO2 stripping flux compared to traditional membranes. The bead-on-string membranes show superior long-term CO2 stripping flux, suggesting potential for membrane distillation applications.