Clathrate Hydrate Formation from Cyclopentane-in-Water Emulsions

This paper reports the experimental examinations of hydrate-forming cyclopentane-in-water emulsions as potential thermal energy storage media for air-conditioning systems. It was demonstrated that an adequately compounded cyclopentane/water/surfactant mixture formed a stable emulsion with the aid of continuous agitation and, through its cooling to ∼2 °C, turned into a bulky mass of granular hydrate crystals. The behavior of the hydrate formation was investigated by varying the amount and composition of the surfactant (or surfactant mixture) in the sample cyclopentane/water/surfactant mixture from run to run in order to determine the appropriate preparation of the mixture for efficient hydrate formation. Also performed were measurements of the effective heat of dissociation for the granular hydrate products obtained in the above hydrate-forming experiments. The measurements showed that the effective heat of dissociation can be as high as ∼93% of the intrinsic heat of dissociation of cyclopentane hydrate crystals, thereby indicating a sufficient potential of the cyclopentane-in-water emulsions as thermal energy storage media.