(286d) Clathrate Hydrate Formation Using Fluorocarbons

Global demand for freshwater continues to increase and as a response to this pressing need, hundreds of desalination plants have been constructed over in the past decade. Most plants utilize reverse osmosis (RO) or multi-stage flash distillation (MSF) as the separation technology. However, pumping large volumes of water to high pressures for RO and the significant thermal heating requirement for MSF makes these technologies expensive. Clathrate hydrates serve as an economic alternative desalination technology if it can be operated near ambient conditions. Fluorocarbon refrigerants have shown promising results as clathrate formers for producing clathrates at such conditions. However, concerns regarding global warming potential and ozone depletion have limited the extent to which some fluorocarbons can be used.
Understanding the conditions in terms of temperature and pressure at which clathrates form between fluorocarbons and water is an important aspect in evaluating optimum clathrate formers. Our studies use accurate gravimetric and volumetric techniques to measure sorption of different fluorocarbon gases into water to determine phase transition conditions. Combining these two methods allows us to investigate the solubility of the refrigerant in water and the rate of formation of the clathrates.