PREPARATION AND STUDY OF SOME METAL SUPPORTED PETROLEUM REFINING CATALYSTS

Abstract

The present work deals with the preparation of petroleum refining catalysts namely nickel and cohalt with different loadings (2, 5 and 8% w/w metal) on different supports (y-alumina, silica, amorphous synthetic and natural crystalline alumo-silicates). The work investigates the mutual effects of metals and supports, as well as the production of suitable isomerization and dehydrogenation catalysts. The cracking and isomerization activities of the prepared catalysts were investigated through n-hexane conversion. The hydrogenation-dehydrogenation activity was tested through cyclohexane conversion. Catalytic conversion experiments were carried out using pulse flow system attached to gas chromatograph.

The main conclusions drawn from this study can be summarized as follows :- • Total conversion of both n-hexane and cyclohexane increases with temperature and metal loading. However, the total conversion of both reactants in presence of cobalt catalysts is greater than in case of nickel catalysts due to high cracking gas formation. • Nickel catalysts under investigation are more active and selective towards n-hexane isomerization and cyclohexane dehydrogenation as compared with cobalt catalysts. This is attributed to the higher hydrogenation­ dehydrogenation efficiency of Ni as a resu It of its higher electron affininty. Such catalysts could be used for upgrading of petroleum distillates to obtain high octane gasoline, low freezing point civil and military jet fuel.