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Hydrate-based desalination is a promising technology that offers low energy consumption. However, the low hydrate conversion rate and sluggish hydrate formation still hinder its applicability and therefore has not been commercialized yet, as it is necessary to enhance hydrate formation kinetics and obtain more freshwater. Hence, this study introduces a dual function (thermodynamic and kinetic) promoter cyclopentane and hydrophobic graphite and investigates the effect of cyclopentane/water volume ratio from 0.05 to 0.325, graphite size (75 μ m − 1. 6 μ m), and graphite/water volume ratio (ranging from 0.625 mg/mL to 3.25 mg/mL) on the CO 2 + C 3 H 8 hydrate formation kinetics at 275.6 K and 2.0–3.0 MPa. The results indicated that cyclopentane could shift the hydrate phase equilibrium condition to low pressure and high temperature and accelerate CO 2 + C 3 H 8 hydrate formation. Additionally, the experimental findings highlighted that the cyclopentane/water volume ratio of 0.175 afforded a faster hydrate formation rate and water conversion to hydrate. Moreover, we demonstrated that hydrophobic graphite with a smaller size provided more sites for hydrate nucleation and growth, and the synergy of graphite and cyclopentane reduced the hydrate induction time from 8.25 (±4.42) mins to 1.95 (±1.7) mins and increased the hydrate conversion rate from 35.62 (±1.76) % to 43.25 (±0.14) %. Overall, this study provides a guide for selecting the appropriate experimental condition, promoter, and porous media and lays a foundation for the hydrate-based desalination technology's feasibility and sustainable development. [Display omitted] • Cyclopentane combined with graphite to enhance hydrate formation rate was studied. • Synergy of cyclopentane and graphite shortens the hydrate induction time. • Cyclopentane/water volume ratio of 0.175 shows the fastest hydrate formation rate. • Graphite size of 6. 5 μ m indicates the highest gas uptake and hydrate conversion rate. [ABSTRACT FROM AUTHOR]