The report describes a thermodynamic framework, established for the development of a model of the phase equilibria of mixtures of methanol and the major constituents found in gases produced from coal. Two approaches were used to model the equilibrium behavior: (1) an equation of state was used to describe both gas and liquid phases, and (2) an equation of state was used to describe the gas while a solution model involving activity coefficients was used to describe the liquid. The approach chosen for each species was based on the component volatility. An experimental apparatus was constructed to obtain data against which the model predictions could be tested. The comparison was favorable. P-T-x-y data on mixtures of CO2, methanol, and water, and mixtures of CO2, nitrogen, and methanol at temperatures in a range of -30 to 25 C and pressures up to 54 atm (5472 kPa) were obtained. Comparisons of the calculated and measured values of bubble point pressures and/or liquid compositions of the dissolved gases were satisfactory.