The effect of water temperature and composition on Henryʹs law constant for various PAHʹs

Henryʹs Law Constants (H) for benzene, naphthalene, phenanthrene and anthracene were experimentally determined at various water temperatures (5°C to 35°C) in distilled water using an on-line monitoring technique. The results from these experiments were compared to the values available in the literature and to the ratio of vapor pressure and solubility data using experimental and calculated data. The effect of salt concentration on H for naphthalene was measured at 25°C. H values increased with salt concentration and were proportional to the decrease in solubility of naphthalene in water. A good correlation between the observed H for naphthalene in sea water as a function of temperature and the ratio of vapor pressure and solubility was observed.