Hydrate method to capture and store CO2 under sea floor as one of the most novel and promising methods to deal with the greenhouse effect and reduce carbon emission has gained increasing attention nowadays. But how to grow CO2 hydrate under promotion in confinement has rarely been exploited. Here the growth of CO2 hydrate with tetrahydrofuran (THF) promoter in confinement was systematically investigated by molecular dynamics simulations, with the counterpart growth but without promoter as a comparison. With promoter, an obviously more rapid growth of CO2 hydrate was observed and CO2 molecules went inside water cages along with the THF ones but not gathered into bubbles during the formation of clathrate. However, the gathering of CO2 bubbles in the system without promotion hindered the obvious formation of clathrate. The vivid movies and physical quantities were analyzed in detail in order to further unravel the physical mechanism of the growth process and the promotion effect of THF. The obtained simulation results proved that THF could indeed promote the confined growth of CO2 hydrate by preventing the formation of large CO2 bubbles, providing a theoretical foundation for the geological storage of CO2 hydrate in permafrost areas and marine sediments.

中文翻译：

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CO2 水合物的快速生长是缓解温室效应的一种有前途的方法


在海底捕获和储存 CO2 的水合物方法作为应对温室效应和减少碳排放的最新颖和最有前途的方法之一，如今越来越受到关注。但是，如何在密闭条件下种植二氧化碳水合物很少被开发。在这里，通过分子动力学模拟系统研究了具有四氢呋喃 （THF） 启动子的 CO2 水合物在限制中的生长，与对应的生长但没有启动子进行比较。使用启动子，观察到 CO2 水合物明显更快地生长，CO2 分子与 THF 分子一起进入水笼，但在笼状物形成过程中没有聚集成气泡。然而，CO2 气泡在系统中聚集而没有促进，阻碍了包合物的明显形成。详细分析了生动的电影和物理量，以进一步揭示 THF 生长过程的物理机制和促进作用。所得模拟结果证明，THF 确实可以通过阻止大 CO2 气泡的形成来促进 CO2 水合物的有限生长，为多年冻土区和海洋沉积物中 CO2 水合物的地质封存提供了理论基础。