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: