EXPERIMENTAL-STUDY ON PROPANE HYDRATE EQUILIBRIUM CONDITIONS IN AQUEOUS-ELECTROLYTE SOLUTIONS

Hydrate equilibrium data (aqueous solution - gas - hydrate) on propane hydrates in electrolyte solutions containing NaCl, KCl, CaCl2 and the ir binary and ternary mixtures, and in a synthetic sea water were expe rimentally obtained in the temperature range 263 - 276 K using a ''pre ssure search'' method. The ionic strengths of the solutions ranged fro m 0.7 to 4.77 in molality units. The data obtained in 10 wt% NaCl solu tion in this work were close to one set of published data but were in disagreement with two other sets of published data having their own mu tual disagreement. The inconsistency was investigated by employing a ' 'temperature search'' method for this solution. The two sets of data o btained in this work by the two different procedures were in close agr eement with each other. The predictive method of Englezos and Bishnoi was used to compute the equilibrium pressures at the experimental temp eratures for all the electrolyte solutions studied. The computed value s matched the experimental data obtained in this work very well, inclu ding those for 10 wt% NaCl solution.