In this study, a membrane prepared by gelling trihexyl(tetradecyl)phosphonium dicyanamide ionic liquid (IL) with poly(vinylidene fluoride-co-hexafluoropropylene) copolymer is tested for performance and stability in pervaporative separation of 1-butanol. Feed concentration and temperature affected separation performance mainly through plasticizing and swelling effects in the membrane which promoted liquid-like transport behavior. Microscale IL-in-polymer networks formed within the gel matrix where the neat IL possibly functioned as conventional liquid membrane. IL gelling has significantly improved the membrane operational lifetime to approximate to 80h, a significant improvement on the approximate to 10h shown by a simple supported IL membrane counterpart. The instability was consequent to polymer-IL incompatibility and so further investigations are underway to resolve this issue.