Influence of Tetra n-Butylammonium Chloride and Polysorbate 80 on the Kinetics of Methane Hydrate Formation

抄録

The presence of semiclathrate hydrate former salts such as tetra n-butylammonium chloride (TBAC) mild the thermodynamic conditions of hydrate formation, considerably. As opposed to the abundant studies undertaken on the thermodynamics of hydrate forming in the presence of these salts, their kinetics needs further investigation. In this research, the kinetics of methane-TBAC semiclathrate hydrate forming has been focused on. The effects of the polysorbate 80, various weight fractions of TBAC, and beginning pressure of the cell on the moles of gas encaged in hydrate cavities and storage capacity of formed hydrates are investigated. The tests were carried out in the isothermal condition of 276.65 K. The results revealed that by raising the weight fraction of TBAC from 5 to 15 wt%, the moles of gas encaged in hydrate cavities and storage capacity of formed hydrate decreases. Utilization of polysorbate with a concentration of 15 ppm along with TBAC, promotes the kinetics of semiclathrate hydrate forming process (HFP) and raises the storage capacity, compared to TBAC aqueous solution. Finally, the influence of the beginning pressure of the cell on the kinetics of TBAC-methane hydrate forming is studied. Results indicate that by raising the beginning pressure of the cell, the moles of gas encaged in hydrate cavities and storage capacity raises.