George Schweitzer

Alumni Distiguished Service Professor
Inorganic Chemistry

Lanthanide chemistry; ion exchange processes

B.A., Central College (1945)
M.S., University of Illinois (1946)
Ph.D., University of Illinois (1948)

NSF Faculty Fellow

Research

In our research group, we are pursuing several lines of experimental investigation.

We are preparing polymeric substances in which a metal chelate with polymerizable ligands is incorporated in a styrene/divinylbenzene matrix. Pulverization and acid treatment are employed to remove the metal ion, leaving the polymer with cavities lined with coordinating agents to fit the size, coordination number, coordination geometry, charge, and bonding characteristics of the original metal ion and no others. The systems are characterized by equilibrium and rate studies. The aim is to produce highly-selective cation absorbents for use in metal separation, removal, recovery, and refining.
A second project involves investigations of the perturbations of laser-induced lanthanide-ion fluorescence spectra by other cations and anions. Lanthanide ions form charged complexes with a number of polydentate chelating agents, and these substances exhibit very narrow fluorescence lines. These complexes carry a cation or an anion. Different cations or anions shift the fluorescence line differently, giving rise to the possibility of a multi-ion analytical technique.
A third research area in which we are working is the characterization of ion-exchange equilibria of carboxylic, phosphonic, phosphinic, sulfonic, and dual-function chelating resins. Selectivity coefficients are being determined for numerous cations, and quantitative affinity series are calculated. These approaches are meant to quantitatively define the abilities of various resins to separate cations.
A fourth project has to do with the determination of standard EMF potentials of ion exchange resins with reducing exchange groups. These substances are useful for the isolation and separation of reducible ions, and a knowledge of their standard potentials permits calculations which optimize their use.
A fifth experimental investigation treats the use of ion-exchange resins in the hydrogen form as agents for the selective dissolution of insoluble inorganic compounds including minerals and industrial wastes.
A further project involves the improvement of analytical techniques for the monitoring of low-level radioactive contamination in water and foods. Ion-exchange concentration and separations are coupled with gamma spectroscopy and liquid scintillation counting to provide rapid and accurate methods.

Representative publications

Luminescence study of europium chloride. N.A. Stump, G.K. Schweitzer, J.K. Gibson, R.G. Haire, and J.R. Peterson, Appl. Spectrosc. 48, 937 (1994).

Luminescence study of cation exchange in sodium europium pyridinedicarboxylate. N.A. Stump, G.K. Schweitzer, G.M. Murray, and J.R. Peterson, J. Lumin. 60/61, 104 (1994).

Perturbations of luminescence of europium-EDTA salts by cations. L.L. Pesterfield, N.A. Stump, G.K. Schweitzer, and J.R. Peterson, J. Alloys Comp. 180, 201 (1992).

Preparation of site-selective ion-exchange resins. D.A. Harkins and G.K. Schweitzer, Separ. Sci. and Tech. 26, 412 (1991).

Corrosion system modeling using microcomputer programs for free-energy minimization. G.M. Murray, G.K. Schweitzer, and F.A. Haecker, Corrosion 46, 95 (1990).

Cation affinity series for comparable carboxylic, phosphinic, and sulfonic ion-exchange resins. G.K. Schweitzer, A.M.M. Radzi, and S.D. Alexandratos, Analyt. Chim. Acta 225, 322 (1989).

Biographical sketch

Dr. Schweitzer earned his B.A. in chemistry from Central College in 1945, his M.S. in chemistry from the University of Illinois in 1946, and his Ph.D. in chemistry from the University of Illinois in 1948. Dr. Schweitzer also earned an M.A. in philosophy from Columbia University in 1959 and a Ph.D. in philosophy from New York University in 1964, and was awarded a Sc.D. for his work in the history of science in 1965. He joined the faculty at the University of Tennessee in 1948 and has done and continues to do research and consult with several of the facilities at Oak Ridge: K-25, Y-12, ORNL, ORAU, AEC, UT-AEC, ARP. Dr. Schweitzer has been the recipient of numerous awards, fellowships, and lectureships, including an NSF Faculty Fellowship (1959-60).

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