Thermodynamic behavior of hydrogen‐hydrocarbon mixtures

By use of the Benedict‐Webb‐Rubin (BWR) equation of state an attempt has been made to correlate experimental vapor‐liquid equilibrium data on hydrogen‐methane‐propane mixtures in the temperature range from 0° to −250°F. and pressure range from 500 to 1,500 lb./sq. in. abs. Considerable improvement in hydrogen K values has been obtained by adjusting the coefficient ν in the BWR equation for hydrogen. In the final adjustment it was necessary to specify a new value of ν for hydrogen at each temperature. The root‐mean‐square deviation of calculated from observed K values for hydrogen is 6.6% As a further check the recommended BWR coefficients for hydrogen have been used to calculate the low‐temperature hydrogen K values in mixtures with ethane and ethylene with good results. The predicted K values for propane at temperatures below −150°F. have not been altered and are still in error by as much as 2 orders of magnitude.