Recovering ethyl acetate from aqueous solution using P(VDF-co-HFP) membrane based pervaporation

Poly (vinylidene fluoride-co-hexafluoropropene) (P(VDF-co-HFP)) was introduced as a novel membrane material for the pervaporation process. To enhance permeation flux, the multi-layered composite membranes were prepared using P(VDF-co-HFP) as skin layer on polypropene (PP) nonwoven fabric. The pervaporation properties of the P(VDF-co-HFP) /PP composite membranes for separating ethyl acetate (EtAc) from water solution were investigated and compared with those of poly (dimethylsixolane) (PDMS) and poly (ether block amide) (PEBA)membranes. It was found that EtAc concent in permeate could be as high as 60-90 wt% while the EtAc concentration in feed of EtAc/water mixture below 5.0 wt%. The relationships between pervaporation properties and the swelling in skin layer were discussed. Basing on these composite membranes had comparable performance to PDMS and PEBA membranes, it was indicated that P(VDF-co-HFP) should be a potential candidate in pervaporarion for separating organics from aqueous mixtures.