Bs. Xing et al., CROSS-CORRELATION OF POLARITY CURVES TO PREDICT PARTITION-COEFFICIENTS OF NONIONIC ORGANIC CONTAMINANTS, Environmental science & technology, 28(11), 1994, pp. 1929-1933
Accurate sorption coefficients are: important for models to predict fa
te and movement of organic chemicals in soils or sediments. We report
here on a new method for predicting partition coefficients (K-d) of no
nionic chemicals onto soils and geological materials. It includes prop
erties of sorbents and of sorbates, thereby yielding more accurate org
anic carbon-normalized partition coefficients (K-oc) than a single val
ue derived from an octanol-water partition coefficient (K-ow). A regre
ssion of log K-oc on log K-ow and polarity index (PI: [(O + N)/C]) was
established using benzene, toluene, and o-xylene as sorbates and usin
g model organic polymers as sorbents K-oc data for sorption of o-xylen
e onto soils and geological materials were used in a rearranged form o
f the regression equation to determine effective polarity of the soils
, Effective polarity was then used together with the respective K-ow v
alues to predict K-oc of benzene and toluene on each soil. This method
provides a range of K-oc values that are soil sensitive. The effectiv
e polarity provides a new parameter to describe soil organic sorbents
and includes any influence that mineral components may exert on the so
rptive properties. of organic matter.