Investigation of Ionic Liquid as Hydrate Inhibitor at Different Range of Temperature and Pressure

Hydrate is an ice-like structure which is formed by the interaction between water molecules and natural gas at high pressure and relatively low temperature. Methane hydrate deposit is identified at deepwater marine settings and permafrost settings [1]. In this project, the equilibrium phase of methane hydrate is measured in the presence of ionic liquid as hydrate inhibitor. Ionic liquid is chosen due to its dual function inhibitors which can give thermodynamic and kinetic inhibition effects. In contrast to conventional thermodynamic inhibitor such as methanol and ethanol, ionic liquid is needed in a low dosage and it is environment friendly solvents [2]. The performance of this ionic liquid towards the equilibrium phase boundary of methane hydrate is studied using the hydrates studies system (HYDREVAL). From the literature research studied, 1 wt% of 1-butyl-3-methyl-imidazolium bromide ([BMIM]-Br) is used as ionic liquid and several runs are conducted at pressure range of 3 - 6 Mpa to investigate the performance of [BMIM]-Br at different pressure and temperature. The equilibrium phase of methane hydrate in the presence of [BMIM]-Br is compared with other hydrate inhibitors from previous studies likes methanol and [EMIM]-Cl. In the presence of [BMIM]-Br, there is a temperature shift on the equilibrium phase of methane hydrate. Compare to conventional thermodynamic hydrate inhibitor, methanol shows a significant temperature shift. However, high dosage of methanol is needed to give a significant thermodynamic effect.