Effect of Ultralow Concentration of Methanol on Methane Hydrate Formation

Methane hydrates were produced in an isochoric high pressure cell in the presence of an ultralow concentration of methanol as an additive. Methanol concentrations examined were in the range 1.5−20 ppm by weight. The real gas equation and the nucleation probability distribution have been used to understand the effect of ultralow concentrations of methanol on the amount of hydrate formation, the rate of nucleation, and the range of probability distribution function in which random nucleation of methane hydrates occur. Comparisons with the pure water baseline experiment showed that an ultralow concentration of methanol exhibits dual effect, both as an inhibitor and as a promoter on structure I methane hydrate formation.