The preparation of a series of cobalt-molybdenum (Co-Mo) catalysts
supported on SiO2 and carbonized egg shells were investigated using standard
procedures; the catalysts were further calcined at the 500
o
C temperature to generate
the internally consistent set, and the metal atoms content were varied in a regular
manner. The ratio 1:4 (Co
2+
: Mo
6+
) by weight was employed for the various catalysts
prepared. The carbonized egg shells were divided into two parts: the first part was
leached with HNO3, as the other one was not leached. Activity tests were run using these
catalysts containing leached and unleached carbon for the hydrogenation of methyl
orange; the changes in absorbance regarding the unhydrogenated methyl orange at a
wavelength of 460 nm were respectively 0.07 and 0.067 when the catalyst containing the
leached carbonized egg shell (catalyst A) and the catalyst containing the unleached
activated carbon (catalyst B) were used for the hydrogenation reaction. This confirms
that catalyst A is more efficient in hydrogenating methyl orange than catalyst B.