PHASE-EQUILIBRIA FOR TETRALIN WATER AND 1-METHYLNAPHTHALENE WATER MIXTURES AT ELEVATED-TEMPERATURES AND PRESSURES

Vapor-liquid and liquid-liquid equilibrium phase compositions and vapor-liquid critical points have been measured for tetralin-water and 1-methylnaphthalene-water mixtures at temperatures from 300-400-degrees-C and pressures up to the mixture critical pressure. A flow experimental technique was used for the measurements of phase compositions to minimize thermal degradation of the hydrocarbon at elevated temperatures and to facilitate sampling at elevated pressures. The apparatus contains a high-pressure view cell equipped with sapphire windows to allow visual observation of phase separation, the number of coexisting phases, and critical opalescence. Observations of critical endpoints for three-phase, vapor-liquid-liquid equilibrium have also been made for both hydrocarbon-water mixtures using a static equilibrium cell. These critical endpoints are shown to be sufficient for classifying the pressure-temperature projection of each binary mixture.