Professor James Economy's Group
Novel Organic-Inorganic Hybrid Chelating Materials
The objective of this project is to design novel tailored organic-inorganic hybrid chelating materials for environmental remediation, catalysis, and separations. Up to now, we have prepared a series of these new kinds of materials with tailored porosities in the form of fiber, powder, or granule. The covalently bound organic chelating groups in these materials include thiol, copper (II) ferrocyanide, iminodiethanol, cyclodextrins, calix[n]arenes, etc. These chelating materials are shown to be extremely efficient in removal of trace organic and inorganic contaminants, such as mercury, cesium, silver, humic acid, p-nitrophenol, nitrogen dioxide, from contaminated water or air. Our continuing studies on the preparation and application of these chelating materials are currently in progress.
Permit removal of
trace contaminants in the presence of high concentrations
of Na+ and K+
Polyvinyl Alcohol Mercaptyl Fibers for Arsenite
The work described here entails the synthesis (Fig.1)and characterization of polyvinyl alcohol mercaptyl fibers, coated on a fiberglass substrate, for the purpose of removing arsenite (As ) from water. Because thiols are chemically the most active functional groups found in cells and are capable of forming very stable complexes with metal ions, this functional group was selected as an excellent candidate for arsenite removal from water. The fibers were characterized through infrared spectroscopy, elemental analysis, analytical titration, scanning electron microscopy, and environmental scanning microscopy (Fig.2). The ability of these systems to chelate arsenite was measured using equilibrium adsorption isotherms at initial concentrations of 10 and 100 ppm (Figs 3 and 4). The ability to regenerate these systems is also described. The fibrous mercaptyl systems performance is compared to the commercial product, Duolites GT-73, a macroreticular polystyrenedivinylbenzene resin with chelating thiol functional groups.
Fig. 1. Polyvinyl alcohol mercaptyl fiber synthesis.
Ref. L. Dominguez, Z. Yue, J. Economy, and C. L. Mangun. Design of polyvinyl alcohol mercaptyl fibers for arsenite chelation. Reactive & Functional Polymers 53(2-3), 205-215. (2002)