Clathrate hydrate equilibria in mixed monoethylene glycol and electrolyte aqueous solutions

► New water activity of mixed salt(s) and MEG aqueous solutions were measured. ► New 3-phase H-Lw-V data for methane and a natural gas in equilibrium with MEG and NaCl solutions are reported. ► The CPA-EoS combined with a modified Debye Hückel electrostatic term is employed to model the phase equilibria. ► Water activity data were used to adjust parameters of the modified Debye Hückel electrostatic term. ► The modified model was independently validated using hydrate data.