Abstract
We studied the adsorption of two s-triazine and two substituted urea herbicides by three different soil humic acids, using elementary analyses and infrared spectroscopy.Obtained data show that adsorption occurs in all cases, involving such mechanisms as ionic bonds, only for the s-triazines; H-bonding; van der Waals forces; and possibly charge transfer in both s-triazine-HA and substituted urea-HA complexes.The extent of adsorption is higher for s-triazines than for substituted ureas, in the order: prometone > methoprotryne > monuron > fenuron. We studied the adsorption of two s-triazine and two substituted urea herbicides by three different soil humic acids, using elementary analyses and infrared spectroscopy. Obtained data show that adsorption occurs in all cases, involving such mechanisms as ionic bonds, only for the s-triazines; H-bonding; van der Waals forces; and possibly charge transfer in both s-triazine-HA and substituted urea-HA complexes. The extent of adsorption is higher for s-triazines than for substituted ureas, in the order: prometone > methoprotryne > monuron > fenuron. © Williams & Wilkins 1980. All Rights Reserved.