Sol-gel monoliths for optical copper (II) determination

Author

Cheri Whitehead Clavier

Date of Award

12-2001

Degree Type

Thesis

Degree Name

Master of Science

Major

Chemistry

Major Professor

Ziling (Ben) Xue

Committee Members

Craig E. Barnes, S. Douglass Gilman

Abstract

Heavy metal ions are used in a variety of industrial applications and many are considered pollutants. Currently, metal ion concentration measurements are determined off-site, using techniques that are costly, time-consuming, and inconvenient. This work describes the development of optical Cu²⁺ sensors prepared through the sol-gel process. Initial work was carried out exploring the basic properties of sol-gel glasses with amine ligands incorporated directly into the sol-gel matrix. The sol-gel process was modified to produce physically robust, optically transparent, crack-free sol-gel monoliths incorporating either diamine NH₂(CH₂)₂NH(CH₂)₃Si(OMe₃)₃ or monoamine H₂N(CH₂)₃Si(OMe)₃ directly into the sol-gel matrix using Si(OMe)₄ as a cross-linking agent. The kinetics of cupric ion uptake by the gels in Cu²⁺ solutions of various concentrations was studied by measuring the change in the absorbance of the blue metal:ligand complexes within the gels over time using UV-VIS spectrophotometry. A simple correlation between the rate of complex formation and [Cu²⁺] in solution was observed. The gels containing diamine ligand could not be regenerated, and could therefore only be used as one-time Cu²⁺ probes, possibly in environmental applications. The gels containing monoamine ligand could be regenerated with EDTA and used in subsequent Cu²⁺ uptake-removal cycles, and thus showed potential as industrial Cu²⁺ ion sensors.

Recommended Citation

Clavier, Cheri Whitehead, "Sol-gel monoliths for optical copper (II) determination. " Master's Thesis, University of Tennessee, 2001.
https://trace.tennessee.edu/utk_gradthes/9581