Phase equilibrium data of mixed carbon dioxide and tetrahydrofuran clathrate hydrate in aqueous electrolyte solutions

The phase behavior of a system consisting CO₂ hydrate is of great importance for many industrial and natural processes. On the one hand, CO₂ and water are part of natural gas streams and also they are found in oil reservoirs during EOR. In light of this, data for systems containing CO₂ and a promoter in aqueous electrolyte solutions are presented. The organic component chosen as promoter is tetrahydrofuran (THF). THF shows a hydrate promoting effect, which is concentration-dependent ≤ 7 mole % of THF in the aqueous solution. At higher concentration, THF shows an inhibition effect of hydrate formation. In contrast, all electrolytes show inhibition effects at all concentrations. Adding electrolyte such as NaCl causes the equilibrium pressure to increase significantly. This is an abstract of a paper presented at the 2007 AIChE Annual Meeting (Salt Lake City, UT 11/4-9/2007).