PARTITIONING OF POLYCYCLIC AROMATIC-HYDROCARBONS FROM DIESEL FUEL INTO WATER

An experimental evaluation of a model derived using Raoult's law convention for activity coefficients and hypothetical supercooled liquid solubilities is presented for the partitioning of eight polycyclic aromatic hydrocarbons (PAHs), all solids in their standard state, between four diesel fuels and water. The UNIFAC (UNIQUAC functional group activity coefficient) model was used to calculate the likely nonidealities resulting from interactions between components in the diesel fuel. Both the UNIFAC model simulations and the observed diesel-water partition coefficients suggest that, for the PAHs examined, the extent of nonideality is sufficiently small (i.e., errors remain within a "factor of 2"), such that Raoult's law may be acceptable for most field-scale applications.