Accelerative Effect of Carbon Nanotubes and Lecithin Coupled with Loofah Matrix on the Kinetics of Methane Hydrate Formation

Methane hydrate (MH) has attracted considerable attention as a safe and efficient method for storing and transporting natural gas. Its rapid formation and high storage capacity are key factors in natural gas storage and transportation technology. Given this background, this study aimed to improve the kinetics of MH formation and investigated the synergistic effect of carbon nanotubes (MCNTs) and lecithin (PC) in loofah supports to promote the formation kinetics of MH. It was found that the induction time was shortened by 92.40 to 94.30% when the concentration of MCNTs in the dynamic system was increased from 0.005 to 0.025 wt % compared to the pure water system, and the maximum gas storage could reach up to 142.83 V/V, with 0.015 wt % MCNTs having the greatest effect. On this basis, in the static system constructed by coupling loofah, the formation of MH was significantly accelerated by the synergistic effect of MCNTs and loofah, the induction time was shortened by 93.60%, and the gas storage capacity was increased by 23.03% compared to the dynamic system with 0.015 wt % MCNTs alone. Furthermore, the introduction of PC shortened the induction time by 50% and promoted the wall climbing growth of MH, although the impact on gas storage volume and water-to-hydrate conversion rate was smaller. Finally, based on the enhancement efficiency and cost-effectiveness evaluation, we found that the coupled system of MCNTs, PC, and loofah excellently promoted the kinetics of MH formation and was economically green. This system offers an efficient, economical, and environmentally friendly new approach to methane storage and transport technology.