open access

https://hdl.handle.net/2115/94092

Supersaturation dependent nucleation of methane plus propane mixed-gas hydrate

英語

2024-02-21

AIP Publishing

Journal of chemical physics

160(7)

074502

Before hydrates can be widely used in industry, we should better understand the problematic issues of hydrate nucleation, particularly its stochastic nature. Here, we report on measurements of the nucleation probability of mixed-gas hydrates in which the guest molecules are a mixture of methane and propane. For the pure cases, at a supersaturation near 1.0, we had previously measured an induction time for the methane hydrate of about 1 h, whereas for the propane hydrate, it was over one day. Using the same experimental setup, we examine here the nucleation probability for a mixture of 90% methane and 10% propane as the guest gas for a range of supersaturations. For the experiments, the temperature was 274 +/- 0.5 K and the stirring rate was about 300 rpm. The experiments were repeated at least ten times under the same condition, exchanging the sample water every time. We define the nucleation probability at a given time as the fraction of trials that nucleated by that time and then determine the nucleation probability distribution. The resulting nucleation frequency is found to have a power-law relation to supersaturation. Then, we examine how the nucleation frequency is affected by the existence of ultrafine bubbles in the initial water. We find that the ultrafine bubbles increase the nucleation frequency but much less than that of typical changes in supersaturation.

学術雑誌論文

Version of Record

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Tsutomu Uchida, Ren Sugibuchi, Masato Hayama, Kenji Yamazaki; Supersaturation dependent nucleation of methane + propane mixed-gas hydrate. J. Chem. Phys. 21 February 2024; 160 (7): 074502 and may be found at https://doi.org/10.1063/5.0189967.

0021-9606