(251a) The Performance of Imidazolium Ionic Liquids and Their Mixtures in Inhibiting Methane Hydrate Formation

The performance of imidazolium ionic liquids, a novel ionic liquid inhibitor for gas hydrate, in inhibiting methane hydrate at low and high ionic liquid concentrations is investigated in a pressure range of 100–300 bar. The effects of different substituents and functional groups of ionic liquid on hydrate dissociation conditions are further explored. Experiments on methane hydrate dissociation conditions in the presence of mixed ionic liquid and conventional inhibitors, such as sodium chloride and monoethylene glycol (MEG), as well as mixtures containing two ionic liquids are also performed to investigate any possible synergistic effects. It is observed that single component solutions of ionic liquid demonstrate a progressive increase in inhibition effect with increasing concentration, which may surpass the effectiveness of MEG at high concentrations. Ionic liquid substituents and functional groups that are effective in inhibiting hydrate formation will be discussed. The thermodynamic inhibition performance of ionic liquid mixtures, which shows synergistic effects, will also be presented.