Abstract
The presence of organic contaminants in water has caused great concern over their potential adverse health impact on humans and animals. Organic contaminants found in water are both naturally occurring and synthetic.
Various chemical and physical water treatment processes are being used to remove organic contaminants. Conventional water treatment methods include the utilization of activated carbon for the removal of organic contaminants. It is generally conceded that activated carbon owes its adsorptive properties primarily to its large surface area, as well as to its pore size. Although activated carbon is nonselective against most of the water contaminants, it does not remove the concentration of organic contaminants to acceptable levels i.e. ppb. Moreover, activated carbon also absorbs moisture from the air and as a result loses its absorptive effectiveness. For this reason attention has been being given to alternative methods for water treatment especially for the removal of organic pollutants.
In this study, cyclodextrin polymers that were water insoluble were synthesized and tested for their ability to remove organic species in water.
Cyclodextrins (CDs) and their corresponding derivatives have been used in a wide range of applications including pharmaceutical and pesticide removal and catalysis. Cyclodextrins are cyclic oligosaccharides derived from enzyme degradation of starch. They are known as molecular hosts capable of including of forming inclusion complexes, with a degree of selectivity, with a range of guest molecules via a noncovalent interaction in their hydrophobic cavities. Although the interaction between cyclodextrin and an organic molecule is the basis for absorption or separation of various organic agents, the solubility of cyclodextrin in water and organic solvents impose limitations to the application of cyclodextrins
in water treatment. Therefore, polymerizing a cyclodextrin monomer with an excess of a bifunctional linker produces an insoluble polymer which can form inclusion complexes with guest molecules.
In this project, the synthesis of a number of cyclodextrin polymers was performed by reacting cyclodextrin with bifunctional linkers.
Dr. B. B. Mamba
Dr. R. W. M. Krause
Dr. T. J. Malefetse