Oxygen isotope effect in disproportionation reactions

A scale of hydrogen isotope separation in the disproportionation reaction is studied experimentally and theoretically: thermal decay and acidic carbonate decomposition and also sulfate and carbonate fluorination. In is shown that thermal carbonate decay is accompanied by an isotope-hydrogen equilibrium in the MeO-CO2 system whereas other types of above disproportionation reactions lead to an intramolecular isotopic effect independent on time and reaction temperature. A magnitude of separation factor during the sulfate fluorination in the 300-550 deg C temperature range is shown to be dependent on a fluorine reagent kind and is controlled by an effect of almost simultaneous rupture of sulfur and hydrogen bonds