and finally Ni–Ca/C spheres (40–70 meshes) were obtained.
The pretreated resin beads were brown.
The spherical product was metallic black after carbonization.
Nickel-doped activated carbon (Ni/AC) was prepared using the impregnation method.
The pretreatment procedures of activated carbon (30–60 meshes ,obtained from China Medicine Co.) included washing with HNO3 (0.5 M) and distilled water and finally drying at 110 C for 5 h.
Its BET specific surface area was measured as 750 m2/g and the pore volume was 0.68 ml/g.
Five grams of the pretreated activated carbon was added to 150 ml solution of Ni(NO3)2 (0.05 M).
The mixture was kept on an 80 C water bath until it dried, then further dried at 110 C for 5 h,
and finally calcined in N2 gas at 500 C for 5 h.