Inhibition effect of ionic liquids and their mixtures with poly(N-vinylcaprolactam) on methane hydrate formation

Abstract Various ionic liquids (ILs) were tested as CH 4 hydrate inhibitors with/without polymeric hydrate inhibitor, PVCap. Equilibrium dissociation conditions for CH 4 hydrate were measured by the isochoric method in the presence of 10 wt% of ILs and they moved towards inhibition region as much as 1.4–1.8 K. Induction times of CH 4 hydrate formation were also measured in the presence of the individual ILs at various concentrations, and of the mixtures of PVCap and ILs. Some ILs showed better CH 4 hydrate inhibition behaviour than did PVCap. The mixtures of PVCap and several ILs exhibited enhanced kinetic inhibition effects for CH 4 hydrate formation.