STUDY OF THE OXIDATION OF OIL-SHALE AND KEROGEN BY FOURIER-TRANSFORM INFRARED-EMISSION SPECTROSCOPY

Infrared emission spectroscopy has been used to monitor the chemical m odifications taking place during the oxidation of bitumen-free Kerosen e Creek shale, the bitumen-carbonate-free shale, and the bitumen-carbo nate-silicate-free shale (kerogen). The samples were heated, in air, a t temperatures in the range 50-700 degrees C at intervals of 50 degree s C. Oxidation of the samples at increasing temperatures showed a stea dy decrease in the signals due to aliphatic hydrocarbons (3000 cm(-1) to 2700, 1460, and 1375 cm(-1)) as well as in the carbonyl/carboxyl si gnals (similar to 1710 cm(-1)) and the carbonyl signal at 1740 cm(-1), along with an increase in the anhydride signals at 1775 cm(-1) and at similar to 1850 cm(-1) Constant temperature (300 degrees C) oxidation produced a steady increase in the anhydride peaks at similar to 1775 cm(-1) and at similar to 1850 cm(-1) while the 1710 and 1740 cm-1 peak s slowly decreased. Of the mineral bands, those characteristic of carb onates totally disappeared at 700 degrees C while the other bands rema ined. The rate of decomposition of organic functionalities is generall y fastest for the bitumen-carbonate-free sample. Analysis of the kinet ic data clearly showed that the presence of carbonates and silicates l owered the activation energy for the oxidation of aliphatic C-H groups .