الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
Environmental protection agency regulations for phasing out lead additives from gasoline had a significant impact on the refinery industry. As a result, there has been a sharp rise in the requirements for octane enhancement processes. The isomerisation of light straight paraffins is the most effective among the available octane enhancement processes. Conventionally, chlorine ion promoted catalyst containing 0.35wt%Pt is used in the majority of refineries. Chlorination of these catalysts has been performed to increase the number and strength of the acid sites of the catalysts because Al2O3 does not acquire strong Br(Rh(Bonsted acid sites which are of great importance to maintain bifunctionality; i.e. strong acidity and strong metallic sites which are capable of providing hydrogenation / dehydrogenation activities. Although Pt/Al2O3 catalysts enjoy high activities at relatively lower temperatures ~ 180oC, they cause corrosion of the sensitive parts of the plants wherein the process is carried out. Hence, the use of originally strongly acidic supports (acidic zeolites) which enjoy acquiring strong Br(Rh(Bonsted acid sites has started by using Hmordenite zeolite. On the other hand, the metal of choice is conventionally platinum, which was contained in the catalytic reforming and hydroisomerisation catalysts in 0.60wt%. Afterwards, this Pt content was decreased to 0.35wt% and combined with one or more Pt promoters. The most frequently used promoters are rhenium, palladium or iridium and many publications discussed their role as catalyst lifetime promoters, but very little information has been focused on their promotion activity. Hence, our work in this thesis is to focus more precisely on the catalytic action of these promoters added to Pt in varying proportions. Moreover, the effect of Pt in varying contents has also been investigated. Also, the support effect on the hydroisomerisation activities of the catalysts has been investigated. The commercially well known HMOR support has been compared with another zeolitic support known as Hbeta (HBEA) which seemed to us acquiring more privilege. The aim of the work is evidently to shed more strict light on the effect of the constituents of the hydroisomerisation catalysts towards the reactivity of nhexane not only concerning isomers production and selectivity, but also concerning the sidereactions associated with isomerisation; namely, hydrocracking and dehydrocyclisation.