General Reserach Interests:

My general research interests are in the area of aquatic chemistry of both freshwater and marine systems. Specific projects involve, the thermodynamics of the interactions of transition metals with both organic and inorganic constituents of natural waters; the catalytic effect of transition metals on both anthropogenic and natural phenolic compounds in the environment; and the effect of co-solvents on ion interactions in aqueous systems.

Thermodynamics of Aqueous Solutions:

The project involving the thermodynamics of the interaction of transition metals with constituents of natural waters have concentrated on their interactions with the major inorganic constituents. These studies have involved volumetric and calorimetric studies to determine the effect of pressure and temperature on these interactions. The systems that we are examining are mixtures of either transition metal chlorides or sulfates with NaCl, MgCl2, HCl, NaSO4, MgSO4 or H2SO4. The transition metal ions involved in these studies are Mn2+, Co2+, Ni2+, Cu2+, Zn2+, & Cd2+. The work on organic constituent interactions with transition metals has concentrated studies of substituted phenols. These studies have involved both the calorimetric determination of heats of complexation and the spectrophotometric determination of equilibrium constants. The substituted phenols that have been examined are catechol, salicylic acid and caffeic acid.

The Catalytic Oxidation of Organic Compounds Natural Waters

The studies of the catalytic effect of transition metals on organic compounds in natural waters grew out of complexation studies of caffeic acid. We found in our studies that under certain conditions trace metals catalyzed an oxidation and subsequent polymerization of caffeic acid instead of simple complexation. This work has been expanded to examine the fate of other naturally occurring organic compounds as well as some man-made compounds. These studies include an examination of the importance of other parameters including light, oxygen, pH, and solid substrates on the oxidation of the compounds. This work utilizes UV/Visible spectroscopy and High Performance Liquid Chromatography.

Thermodynamics of Mixed Solvent Systems:

The studies of the effect of a co-solvent on the interactions of ions in aqueous systems are also an outgrowth of the aqueous ion interaction studies. This work is aimed at modifying existing models to be able to handle the effects of the co-solvent on the ion-interactions. These experiments involved volumetric and calorimetric studies of the mixed solvent system for comparison with similar aqueous studies.