Journal
CHEMOSPHERE
Volume 65, Issue 11, Pages 2074-2081Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.chemosphere.2006.06.048
Keywords
dihydroxybenzoic acid; carboxylic group; inner-sphere complexation; natural organic matter; phenolic group
Categories
Ask authors/readers for more resources
The role of phenolic groups in the interaction of natural organic matter (NOM) with metal hydroxides was investigated with ATR-FTIR spectroscopy and adsorption tests by employing a series of dihydroxybenzoic acids (DHBAs) as the NOM surrogates and aluminum hydroxide as the adsorbent. All DHBAs examined in this study were found to be adsorbed on aluminum hydroxide by forming inner-sphere complexes. Carboxylic groups governed the complexation of DHBAs with aluminum hydroxide at low pH or in cases when the two hydroxyl groups were not adjacent to each other and neither of them was ortho to the carboxylic group. The involvement of the phenolic groups, ortho to another phenolic group or ortho to the carboxylic groups, in the complexation increased with increasing pH as the deprotonation of phenolic groups was easier at higher pH. The presence of phenolic groups increased the electron density of the carboxylic groups and facilitated the inner-sphere complexation of the carboxylic groups with metal hydroxide. The correlation between the pK(a) values and the amount of organic acid adsorbed on the aluminum hydroxide revealed that the adsorption of DHBAs at acidic pH was largely dependent on the surface chelate formation rather than on the electronic effect. (c) 2006 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available