Normally, molecular diffusion of contamination across the sediment-water interface is driven by chemical concentration gradient, then diffusive flux of dissolved contaminants from pore water to overlying water could be estimated through Fick’s First Law on this assumption.
In many previous reports, this Law was used to calculate the diffusive flux for many dissolved inorganic species (like nutrients and heavy metals). So, I want to know whether this Law could also be true for the cases of HOCs?
Besides, according to the Fick's equation, Ds (cm2 s-1), the sediment diffusion coefficient of the species derived from the diffusion coefficient D0 (cm2 s-1) of the species at infinite dilution. This parameter is crucial for getting the diffusive flux. However, there are few publications that report the values of several typical HOCs (such as 16 priority PAHs) under specific experimental conditions. Then, are there some theoretical approaches to get this parameter?
Thanks!