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Biosurfactants catalyzed natural gas hydrate formation in sand/clay packs saturated with seawater. Representative samples from the five possible biosurfactant classifications enhanced hydrate formation rate and decreased hydrate induction time. Biosurfactants increased rates 96% to 288% and decreased induction times 20% to 71% relative to the control. Micellar‐forming rhamnolipid reached a critical micellar concentration at 13 ppm at hydrate‐forming conditions; these micelles migrated readily through a seawater‐saturated sand pack to catalyze hydrate formation in another zone. The type of biosurfactant, in conjunction with specific porous media, help determine massive, dispersed, nodular, or stratified forms of hydrates. Results suggested that minimal microbial activity in ocean‐floor sands can greatly influence gas hydrate formation.

The need for alternative fuels to replace liquid petroleum-based fuels has been accelerated in recent years by environmental concerns, concerns of shortage of imported liquid hydrocarbon, and congressional prompting. The fact is accepted that natural gas is the cheapest, most domestically abundant, and cleanest burning of fossil fuels. However, socio-economical and technical handicaps associated with the safety and efficiency of on-board fuel storage inhibit its practical use in vehicles as an alternative fuel. A concept is presented for safely storing fuel at low pressures in the form of hydrates in natural gas vehicles. Experimental results lead to gas storage capacities of 143 to 159 volumes/volume. Vehicle travel range could be up to 204 mi. Controlled decomposition rate of hydrates is possible for feeding an automotive vehicle. Upon sudden pressure decrease in the event of a vehicle accident, the rate of release of hydrocarbons from the hydrates at constant temperature is 2.63 to 12.50 percent per min, slow enough to prevent an explosion or a fireball. A model is given for predicting the rates of gas release from hydrates in a vehicle wreck. A storage tank design is proposed and a process is suggested for forming and decomposing hydrates on-board vehicles. A consistent fuel composition is obtained with hydrates.