The Promotion Effect of Tetra n-Butyl Ammonium Fluoride (TBAF) on Methane Hydrate Formation

One of the main limitations in the process of hydrate formation for its positive application is the requirement of high pressures and low temperatures. Establishing a unit with these conditions is expensive and unsafe. Therefore, finding the methods for the promotion of this process is very important. The utilization of ammonium salts in water noticeably promotes the hydrate formation conditions. One of these salts is tetra n-butyl ammonium fluoride (TBAF). In this research, the equilibrium data of semi-clathrate hydrate for the system of water/TBAF/methane have been measured and reported. Three concentrations of TBAF (2, 5, and 15 wt.%) were used for the experimental measurements. The comparison of the measured data with the simple hydrate (the hydrate for the system of water/methane) equilibrium data showed the high promotion effect of TBAF on methane hydrate formation. By increasing the concentration of TBAF, its promotion effect increases and the hydrate formation P-T curve shifts to the right side.