Reactions between fulvic acid,a soil humic material,and dialkyl phthalates

Summary Fulvic acid, a water-soluble soil humic material that occurs widely in soils and waters, can complex hydrophobic dialkyl phthalates and make them soluble in water. The extent of the reaction depends on the type of phthalate. Thus, one number-average molecular weight of FA can solubilize four moles of bis(2-ethylhexyl) phthalate but only one mole of dibutyl phthalate, while 2 number-average molecular weights of FA can interact with three moles of dicyclohexyl phthalate. IR spectroscopy failed to provide evidence for the occurrence of chemical reactions between FA and the phthalates. The latter appeared to be adsorbed on the surface of the FA molecule.Contribution No. 362.