Abstract
The effects of variations of fluid velocity and sea water concentration due to tidal motion on adsorption of anionic surfactants to suspended solids (SS) were examined. The laboratory experiments gave the following results.
1) There were no significant effects of fluid velocity and pH on the adsorption of linear alkylbenzenesulfonates (LAS) to SS.
2) LAS adsorption was affected by electric conductivity due to the high concentration of coexistent substances. As the electric conductivity increased, the LAS adsorption capacity of SS increased.
On the basis of the above results, field observations of the tidal river in Tokushima city were carried out. The following results were obtained concerning the adsorption of MBAS to SS.
3) The COD of SS increased and the SS concentration in water decreased the MBAS adsorption, respectively. These results were similar to those found in former studies.
4) As the electric conductivity of water increased, the MBAS adsorption capacity of SS was likewise increasd. The result see 2) obtained by the laboratory experiments was confirmed by the field observations.
5) The Freundlich isotherms were applied. k was formulated by the parameters which describe the above characteristics under the assumption that n=1.
In the tidal river, where the coexistent substance concentration has large variations due to sea water intrusion, the coexistent substance has a significant effect on the anionic surfactants adsorption to SS.
