As shown in Tables 1 and 2, Ni–Ca/D152 resins having a variation of nickel contents from 0% to 6.5% were pre- pared by exchanging Ca/D152 with Ni2+ solutions. The carbonization of the Ni–Ca/D152 yielded Ni–Ca/C with
a variation of nickel loadings from 0% to 12% and corre-
spondingly, a production yield variation from 50% to
38%. The mass loss in carbonization increased with the