Gas-liquid phase equilibrium in the system ammonia-hydrogen-nitrogen

Abstract

An instrument has been developed to measure the gas-liquid phase equilibrium in a mixture, which can, as a first approximation, be considered a binary system. The range covered in the experiments on nitrogen-hydrogen-ammonia mixtures was limited to pressures of 10 to 800 atm. and temperatures between 0 and 120° Celsius although these limits were not dictated by principal features of the instrument. The P-t-x relations for the two phases have been measured; the results are presented in diagrams giving the isotherms in the P-x projection, the isobars in the t-x projection and the lines of constant concentration in the P-t diagram. From the shape of the 115°C isotherm it is obvious that the phenomenon of retrograde condensation is realised in this system.