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Stable synthesis of methane hydrate is the best technique to store an ample amount of methane during storage and transportation. However, the use of conventional promoters is limited by marginal improvement in the kinetics of hydrate, which can be addressed by the use of solid particles if synthesized by a single-step technique. Single-step technique facilitates control on the size of synthesized nanoparticles (NPs) which is not possible with a two-step technique or commercial NPs. Thus, in this study, a single-step technique was used to synthesize silica nanofluids of different NP sizes (5–100 nm) and concentrations (0.5–2 wt %) and compare their impact on kinetic of hydrate, stabilized by a conventional surfactant, cetyltrimethylammonium bromide (CTAB). Nanofluids exhibited superior stability with zeta potential between −36 and −48 mV. Properties such as mole consumption, gas consumed, rate of gas consumed, and apparent rate constant were studied at 6 MPa and two test temperatures 274.15 and 277.15 K. NPs offered significant improvements in the kinetic properties of CTAB-based hydrates, resulting in improved induction time by 56%, while moles of gas consumption and apparent rate constant increased by 88.4 and 184% with NP inclusion of 1.5 wt % at 274.15 K. With an increase in the test temperature by 3 K, these properties marginally reduced at 277.15 K but remained 36.84% higher (in storage capacity) than those of conventional CTAB. The NP concentration of 1.5 wt % was found optimum in the hydrate stabilized by solid particles as further NP addition showed reverse behavior and was considered uneconomical as evident from the results of sample composition of 2 wt % SiO2. It is also important to highlight that the single-step technique is able to synthesize NPs of desired size, which is difficult to achieve with the two-step technique where particles are externally procured followed by mixing with intensive energy. The insights of the study are extremely useful for the use of promoters in effective energy storage during transportation.

Gas hydrate is a tremendous source of clean energy found all over the world. The controllable extraction of natural gas for commercial applications from gas hydrates is a difficult and challenging task. In the oil and gas industry, hydrate inhibitors are crucial for flow assurance, especially in subsea and deepwater operations. These hydrates can block pipelines and equipment, leading to flow restrictions, reduced efficiency, and potential safety hazards. Therefore, managing hydrate formation is a key concern in the industry. Also, designing better hydrate inhibitor formulations is becoming the need of the hour as the world is moving toward a more gas-based economy. So, it is very important to understand the effect of these additives on CH4hydrate. However, the mechanism and extent of hydrate inhibition with additives, such as alcohol, are yet to be understood fully. Hence, understanding the CH4hydrate dissociation process and various thermodynamic parameters under the influence of these additives is very important. In this study, an investigation was done to determine the effect of ethylene glycol concentration on CH4hydrate dissociation by molecular dynamic simulation under varying thermodynamic conditions. The water cage integrity is investigated at different times, temperatures, and pressures. To be able to quantify the decomposition and mechanism of CH4hydrate, the radial distribution function (RDF) and total energy were studied. The result of the RDF and mean square displacement of water and ethylene glycol shows that the hydrate cages stability decreases as the temperature increases. When the ethylene glycol concentration was increased from 0% to 5%, gas hydrate dissociation increased. Dissociation of the hydrate system is enhanced by both increasing concentration and temperature or both, respectively. According to the results of this study and previous research findings, such a work would aim to offer effective tips/guidelines for processing hydrate formations and dissociations.