Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1021/es2023835
Title (Primary) Kinetics of desorption of organic compounds from dissolved organic matter
Author Kopinke, F.-D.; Ramus, K.; Poerschmann, J.; Georgi, A.
Source Titel Environmental Science & Technology
Year 2011
Department TUCHEM
Volume 45
Issue 22
Page From 10013
Page To 10019
Language englisch
Abstract

This study presents a new experimental technique for measuring rates of desorption of organic compounds from dissolved organic matter (DOM) such as humic substances. The method is based on a fast solid-phase extraction of the freely dissolved fraction of a solute when the solution is flushed through a polymer-coated capillary. The extraction interferes with the solute-DOM sorption equilibrium and drives the desorption process. Solutes which remain sorbed to DOM pass through the extraction capillary and can be analyzed afterwards. This technique allows a time resolution for the desorption kinetics from sub-seconds up to minutes. It is applicable to the study of interaction kinetics between a wide variety of hydrophobic solutes and polyelectrolytes. Due to its simplicity it is accessible for many environmental laboratories. The time-resolved in-tube solid-phase microextraction (TR-IT-SPME) was applied to two humic acids and a surfactant as sorbents together with pyrene, phenanthrene and 1,2-dimethylcyclohexane as solutes. The results give evidence for a two-phase desorption kinetics: a fast desorption step with a half-life of less than 1 s and a slow desorption step with a half-life of more than 1 min. For aliphatic solutes, the fast-desorbing fraction largely dominates, whereas for polycyclic aromatic hydrocarbons such as pyrene, the slowly desorbing, stronger-bound fraction is also important.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=11741
Kopinke, F.-D., Ramus, K., Poerschmann, J., Georgi, A. (2011):
Kinetics of desorption of organic compounds from dissolved organic matter
Environ. Sci. Technol. 45 (22), 10013 - 10019 10.1021/es2023835