Determination of the subcooled liquid solubilities of PAHs in partitioning batch experiments

Abstract

a b s t r a c tSubcooled liquid solubility is the water solubility for a hypothetical state of liquid. It is an important parameter for multicomponent nonaqueous phase liquids (NAPLs) containing polycyclic aromatic hydrocarbons (PAHs), which can exist as liquids even though most of the solutes are solid in their pure form at ambient temperature. So far, subcooled liquid solubilities were estimated from the solid water solubility and fugacity ratio of the solid and (subcooled) liquid phase, but rarely derived from experimental data. In our study, partitioning batch experiments were performed to determine the subcooled liquid solubility of PAHs in NAPL-water system. For selected PAH, a series of batch experiments were carried out at increased mole fractions of the target component in the NAPL and at a constant NAPL/ water volume ratio. The equilibrium aqueous PAH concentrations were measured with HPLC and/or GC-MS. The subcooled liquid solubility was derived by extrapolation of the experimental equilibrium aqueous concentration to a mole fraction of unity. With the derived subcooled liquid solubility, the fugacity ratio and enthalpy of fusion of the solute were also estimated. Our results show a good agreement between the experimentally determined and published data.

Chronic toxicity of selected polycyclic aromatic hydrocarbons to algae and crustaceans using passive dosing

“…where T m and T are the melting point of the test substance and the temperature of the test in 8K, respectively. A recent study has confirmed the reliability of this approximation for PAHs [37].…”

“…This latter value was calculated by dividing the measured water solubility of the substance by the maximum chemical activity ( a max ), which was computed from the substance melting point using Walden's rule : where T m and T are the melting point of the test substance and the temperature of the test in °K, respectively. A recent study has confirmed the reliability of this approximation for PAHs .…”

A combined experimental and modeling study to evaluate pH-dependent sorption of polar and non-polar compounds to polyethylene and polystyrene microplastics

“… Properties are either taken from EPISuite (molecular weight and log K OW of neutral species) or the PubChem database (pK a ). Subcooled liquid solubilities (WS) were estimated based on melting points according to Kan and Tomson [ 18 ] and Liu et al [ 24 ] …”

Quantitation and prediction of sorptive losses during toxicity testing of polycyclic aromatic hydrocarbon (PAH) and nitrated PAH (NPAH) using polystyrene 96-well plates

“…Subcooled liquid solubility, the water solubility for a hypothetical state of a subcooled liquid (Liu et al, 2013), has been used to model multi-component non-aqueous phase liquids (NAPLs), containing polycyclic aromatic hydrocarbons (PAHs), in ground water and for predicting sorption to laboratory glassware (Liu et al, 2013; Qian et al, 2011). Subcooled liquid solubility can be derived from model system or environmental properties (such as organic carbon or mineral content of the soil), but can also be calculated using thermodynamic properties for the analytes of interest (Liu et al, 2013; Peters et al, 1999, 1997).…”

“…Subcooled liquid solubility can be derived from model system or environmental properties (such as organic carbon or mineral content of the soil), but can also be calculated using thermodynamic properties for the analytes of interest (Liu et al, 2013; Peters et al, 1999, 1997). Previous modeling of chemicals in the environment, including sorption to soil and organic matter, places the focus of the model on properties of the environmental system, rather than the analytes of interest (Karickhoff et al, 1979; Su et al, 2006).…”