Organic cosolvent effects on the sorption and transport of neutral organic chemicals

Soil column miscible displacement techniques were used to investigate the effects of an organic cosolvent (methanol) on the sorption and transport of three neutral organic chemicals, naphthalene, phenanthrene, and the herbicide diuron, through a sandy surface soil. A two-domain, or bicontinuum, first-order mass transfer model described the experimental data well. For the three solutes used in this study, the equilibrium sorption coefficient (K) decreased log-linearly as the volume fraction of methanol (fc) increased. The physical properties calculator of the SPARC computer model was used for generating solute solubility profiles to estimate the slope of the Log K-fc relationship.