Improving gasoline quality via hydroisomerization process under different operating parameters in petroleum refineries: A review

The hydroisomerization process of light naphtha is the chief process to produce high-octane gasoline in petroleum refineries.The reaction mechanism is designed to produce branched hydrocarbons with high octane numbers.The hydroisomerization reaction mechanism over bifunctional catalysts is influenced by both acid and metallic sites on the catalyst surface.Moreover, it was found that the product quality and distribution in this process are highly dependent on the catalyst type and operating conditions in the fixed-bed reactor.The feed quality (light naphtha) is the major challenge in this process due to its direct effect on the catalyst activity, selectivity, and deactivation mechanism (catalyst lifetime).According to the results of many authors, it has been observed that the pre-treatment processes usually carried out on the light naphtha feedstock provided high performance for the applied bifunctional catalysts.Finally, the economic feasibility of this process is a function of the catalyst type and its resistance to the contaminants present in the light naphtha.