Non-aqueous titration of a fulvic acid sample, with use of an internal reference compound.
The use of an internal reference compound in non-aqueous acid-base titrations as a relatively simple, reliable and accurate means of obtaining information on the acidity spectrum of natural organic acids is reported. Acid-base titrations in dimethylformamide, DMF, with tetrabutylammonium hydroxide as the titrant and p-hydroxybenzoic acid as an internal reference compound have been performed to determine the carboxylic acid and the acidic hydroxyl components of a fulvic acid sample isolated from surface water in the Bersbo area, south-east of Sweden. A carboxylic acid capacity of 4.78 +/- 0.05 meq/g and an acidic hydroxyl group capacity of 1.35 +/- 0.03 meq/g were found for the aquatic fulvic acid.
Ephraim
J H
JH
Institute of Theme Research, Department of Water and Environmental Studies, Linkoping University, S-581 83 Linkoping, Sweden.