Exchange between N230 and N228 over Iron Catalysts

The rates of exchange between N228 and N230 obtained on doubly- and singly-promoted iron catalysts is of the right order to be accounted for by assuming that all nitrogen evaporating from the surface of the catalyst is completely equilibrated with respect to the nitrogen isotope exchange. Large concentrations of hydrogen (50 percent H2 in N2) markedly accelerate the reaction. Small traces of surface oxides poison the iron catalysts severely for the isotope exchange.