An evaluation of the adsorption and flotation of nonpolar organic compounds in clay colloid suspensions

Jar test were run to determine the amount of adsorption that occurred. A bench scale DAF unit was used for the flotation process. The samples were analyzed using an ultra-violet spectrophotometer.

The following results were determined from the research. As the surface area (SA) and cation exchange capacity (CEC) increased with each clay, the amount of adsorption that occurred increased. Adsorption was found to be essentially complete after 30 minutes. It was found that the amount of adsorption occurring did not increase proportionally as the amount of clay increased. This indicates that there was a limiting factor in the process. The attraction for adsorption by hydrophobic bonding was not significantly greater than the attractive forces between the water and the organic compounds which results from dipole-dipole interaction and hydrogen bonding. The DAF process was effective in removing the clay and a certain amount of volatilization of the compounds occurred.

The overall process does not remove the compounds to trace levels. Because of this the usefulness of the process is limited in its application. Continued research on selected industrial wastestreams should be done to determine the effectiveness of the overall process.