GEOC 182 |
| Kaori Masuda1, Taishiro Haramaki2, Takahiro Otsuka2, and Satoru Nakashima3. (1) Department of Earth and Planetary Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo, 152-8550, Japan, (2) Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo, 152-8550, Japan, (3) Interactive Research Center of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo, 152-8550, Japan |
| The thermal stability of dissolved organic compounds and their reactions in groundwater are essential for evaluating long-term behavior of organics relevant to resource and environment issues. In order to determine precise kinetic parameters for these reactions, in-situ UV and IR spectroscopic methods have been developed by using heatable solution cells. In-situ UV heating experiments at 100-160 oC for humic acid and salicylic acid gave their thermal decomposition rates with activation energies of around 50 and 80 kJ/mol. In-situ ATR-IR heating cell has been newly constructed and tested for its capability of tracing reactions of several analogues such as amino acids, peptides and sugars up to 200 oC and 20 MPa. The thermal decomposition kinetics of glycylglycine to glycine at 140-160 oC was successfully represented by the first order reactions with activation energy of 123 kJ/mol. These data can provide quantitative bases for the evaluation of lifetime of naturally occurring organics. |
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Vibrational Spectroscopy in the Earth and Environmental Sciences
1:30 PM-4:50 PM, Thursday, April 1, 2004 Marriott -- Marquis NE, Oral
Division of Geochemistry |