Analysis of methane hydrate nucleation in water-in-oil emulsions: Isothermal vs constant cooling ramp method and new method for data treatment

Temperature dependence of methane hydrate nucleation rate in 50 wt% water in oil emulsion was studied within the temperature range from +2 to −6 °C (supercooling values: 13–21 °C). It turned out that the temperature dependence of nucleation rate in this temperature interval cannot be described by the equations of the classical nucleation theory. This point is discussed with use of available literature data. An approach to the analysis of isothermal survival curves is suggested. Using the approach allows us to establish the amount of nucleation centers in the system and their relative activity. A probable number of nucleation centers and the effect of temperature on the manifestation activity of these centers were determined for the obtained experimental data. •The temperature dependence of the rate of methane hydrate nucleation in the w/o emulsion is investigated.•The temperature dependence of nucleation rate could not be described with the equations of the classical theory.•The activation of a nucleation center is a time-dependent process.•It is very probable that the mechanism of gas hydrate nucleation does not correspond to the classical one.•New approach to the analysis of survival curves is proposed.