Juanjuan Li,Wenlong Zhao,Peng Xiao,Hui Zhang,Kang Liu,Meixia Qi,Boxu Yang,Guangjin Chen,Changyu Sun
The ice powder with unfrozen surfactant solution layer (active ice) is efficient in intensifying gas hydrate formation, however, only in a narrow temperature range. To broaden the temperature range, the effects of gas injection mode, gas pressure and temperature, and particle size on the hydrate formation in the active ice were investigated. The results suggested that continuous gas injection enhanced hydrate formation by producing more unfrozen solution layer at low temperatures; the hydrate formation rate and the gas uptake increased with the increase of gas pressure, while increased with the increase of gas temperature only at low ice temperatures; increasing the gas temperature is more effective in smaller ice particles. The suitable temperature range for fast hydrate formation in the active ice was broadened to 273.15 ∼ 266.15 K from 273.15 ∼ 271.65 K. This study improves the feasibility of hydrate-based gas storage or separation via the active ice.
Gas hydrates provide alternative solutions for gas storage & transportation and gas separation. However, slow formation rate of clathrate hydrate has hindered their commercial development. Here we report a form of porous ice containing an unfrozen solution layer of sodium dodecyl sulfate, here named active ice, which can significantly accelerate gas hydrate formation while generating little heat. It can be readily produced via forming gas hydrates with water containing very low dosage (0.06 wt% or 600 ppm) of surfactant like sodium dodecyl sulfate and dissociating it below the ice point, or by simply mixing ice powder or natural snow with the surfactant. We prove that the active ice can rapidly store gas with high storage capacity up to 185 V g V w −1 with heat release of ~18 kJ mol −1 CH 4 and the active ice can be easily regenerated by depressurization below the ice point. The active ice undergoes cyclic ice−hydrate−ice phase changes during gas uptake/release, thus removing most critical drawbacks of hydrate-based technologies. Our work provides a green and economic approach to gas storage and gas separation and paves the way to industrial application of hydrate-based technologies.
危险品化学品经营许可证（带存储）