In the reaction of Y coal with 17O2, the total amount of gas produced increased as the reaction temperature increased. The gas evolved was mainly isotope-free gas generated by the decomposition of oxygen functional groups in the coal. However, gas containing isotopic oxygen was also observed at 40°C, indicating that gas generation occurred via an oxidation reaction with ambient gas. More gas generation was observed in the untreated Y charcoal with moisture, but the ratio of oxygen-free CO2 gas generation was higher.
On the other hand, dry Y coals with faster exothermic rates had a higher ratio of C16O17O.
