Adsorption of organic compounds onto solids from aqueous solutions
The use of solids to remove pollutants is not novel in the sense that solids are used presently for this purpose. For example, the use of charcoal is well known, and the use of alumina in phosphate removal has been investigated. The removal of phenol from aqueous solutions on a variety of solids has been studied in this work. The rationale for this study is as follows. An aqueous solution containing a pollutant (phenol) is a three component system consisting of a solute (phenol) and solvent (water) in contact with a solid. The question arises, what about the removal of the pollutant by the solid? In many instances the kinds of solids that have been used are those which not only compete for the pollutant, but also compete for water. Thus, not only is the interaction between the pollutant and the solid important, but also the Interaction between the water and the sol id. In many systems, for example herbicides, insecticides, and phenol, there is a Iimited solute concentration, which means that there is a basic incompatability in the system to start with. Then as this solution is put in contact with a solid surface, the amount of pollutant and the amount of water removed become relevant. If the solid has an attraction for water in addition to the pollutant, water may be removed and block parts of the solid which could be effective in removing the pollutant. This study has been concerned with the adsorption of phenol from aqueous solutions on several solids chosen to alter the competition of water and phenol for the surface of the solid.