(257ad) Experimental Measurements of Dissociation Conditions for H2O + CO2+ Hexane and H2O + CO2+ Heptane Mixtures in the Hydrate Formation

Gas hydrates are ice-like non-stoichiometric compounds composed of encapsulated gases by water lattice at low temperatures and high pressures so that the guest molecules would have a suitable size to match the size of cavities. Gas hydrates formation leads to blockage of gas pipelines and equipment. Applying inhibitors shifts gas hydrate stability zone to lower temperatures or higher pressures through reduction of water activity so that the gas hydrates are not formed in the flowline. In México there are reservoirs with high content of water (20 % or more) like Cantarell where hydrate formation can be simple. In this work, the clathrates have been formed in aqueous solutions with mass fractions of 0.05 and 0.10 of hexane and heptane. The hydrate dissociation conditions have been measured using a modified apparatus designed and built to operate at pressures up to 40 MPa and temperature range of (253-303) K based in the isochoric method. The combined expanded uncertainties of the dissociation conditions measurements were evaluated to be less than 0.04 % in full scale of pressure, 0.020 K in temperature and 0.0002 % mol in composition.

Keywords: Clathrates, hydrates, dissociation conditions, alkanes.

* To whom correspondence should be addressed Luis A. Galicia-Luna,

E-mail: lgalicial@ipn.mx