Minerals containing molecular water are important phases at shallow levels in Earth's crust. Quantitative models of the stability of these minerals are necessary for predicting their role in the overall geochemical behavior of the earth; however, the fact that molecular water readily enters and leaves these minerals complicates such models. This research project addresses this difficulty through experimental determination of the effects of hydration and dehydration on the stability of zeolites, which are one of the most abundant types of water-bearing minerals. This is accomplished through direct observations of the water content of zeolites as a function of temperature and humidity, and direct measurements of the heat consumed or produced as these minerals hydrate and dehydrate.
Broader impacts of the proposed study include integrated research and educational experiences derived from the direct involvement of graduate and undergraduate students, who will receive training and experience in modern experimental methods and thermodynamic analysis. In addition, the methods of the proposed study will be used to develop innovative classroom exercises to give students hands-on experience in thermochemical methods in the P.I.'s physical geochemistry course. Data generated in the study will be disseminated not only as publications in international scholarly journals, but will also be available for free download on the Internet, thereby contributing to the infrastructure of science. The resultant data will have application not only in geochemistry, but also in materials science (where zeolites are important catalysts and sorbent materials).
