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7637184 
Journal Article 
Effect of salting out on the desorption-resistance of polycyclic aromatic hydrocarbons (PAHs) in coastal sediment 
Oh, S; Wang, Q; Shin, W; Song, DIk; , 
2013 
Yes 
Chemical Engineering Journal
ISSN: 1385-8947 
ELSEVIER SCIENCE SA 
LAUSANNE 
225 
84-92 
English 
WOS:000321313800011 
The effects of ''salting out'' on the sorption and desorption of polycyclic aromatic hydrocarbons (PAHs) in coastal sediment were investigated. The sorption and desorption isotherms of three PAHs (naphthalene, phenanthrene and pyrene) in coastal sediment were linear. The distribution coefficients of sorption (K-d,K-s) and desorption (K-d,K-d) increased with salinity and hydrophobicity (log K-ow). A three-dimensional model was proposed to explain the combined effects of solubility (S), log Kow and the organic-carbon normalized partition coefficient (log K-oc). The sequential desorption of phenanthrene at different salinities of 0-30 ppt from sediment was conducted after sequential sorption at 0 and 30 ppt, respectively. The desorption data was fitted to a biphasic desorption model including linear labile fraction and non-linear desorption-resistant fraction. The linear distribution coefficient (Kd(a)(lab)) for the labile desorption fraction was affected by the salinity in the previous sequential sorption stage, whereas the desorption-resistance parameters such as the maximum capacity of the desorption-resistant fraction (q(max)(res), mg/kg) and the organic carbon-normalized distribution coefficient in the desorption-resistant fraction (K-oc(res), L/kg-OC), were affected by the salinity in the current desorption stage. In conclusion, the salinity increased the sorbed capacity of PAH as well as the desorption-resistance (as indicated by both q(max)(res) and K-oc(res)) due to the "salting out effect". (C) 2013 Elsevier B.V. All rights reserved. 
Coastal sediment; Desorption; Desorption-resistance; PAHs; Salting out; Sorption