Total isomerization process

The Hysomer process produces an increase of about 12 octane numbers in suitable naphtha feedstocks. The process can be operated in conjunction with the Isosiv process (Union Carbide Corp.) for the separation of normal and isoparaffins, achieving complete isomerization of a C-5—C-6 stream. The combined process is trade named TIP (total isomerization process), and results in increases in octane numbers of about 20, rather than the 12 obtained with a once-through Hysomet treatment. 

TOTAL ISOMERIZATION PROCESS OF PARAFFINS Overall Reaction... 

Over 25 plants are operating the total isomerization process (TIP) and this number is growing continuously. Many millions of tons of isomerized paraffins are produced annually by this process. 

Hysomer [Hydroisomerization] A process for converting K-pentane and K-hexane into branched-chain hydrocarbons. Operated in the vapor phase, in the presence of hydrogen, in a fixed bed of a mordenite catalyst loaded with a platinum. Developed by Shell Oil Company and licensed worldwide through UOP. Used in the Total Isomerization process. Now called the UOP Once-Through (OT) Zeolitic Isomerization process. 

LP mordenite doped with platinum is the catalyst used in the Shell Hysomer process for alkane hydroisomerization this can be linked to the Isosiv separation process whereby -/n-alkanes are separated on LTA zeolite. This link is the basis of the joint Shell/UOP Total Isomerization Process (TIP). Similar catalysts have been employed to hydrocrack (i.e. dewax) diesel fuels. There have also been reports of commercial use of mordenite to catalyze methanol amination with ammonia, to produce dimethylamine. 

Mechanistically the elhanol-to-gasoline process is easier to understand than the MTG process because the still somewhat mysterious first C-C bond formation step is absent. When passing the ethanol-water mixture over II-ZSM5 at lower temperature (200 °C) or over zeolite H-Y, only dehydration occurs and ethcnc is obtained [30]. The track to gasoline is then oligomerisation to CVCg alkene, hydrogenation/isomerization e.g. over the TIP-catalyst Pt-H-mordenite (TIP is Total Isomerization process). 

The normal isoparaffin seperation process used most often is the Union Catbide IsoSiv process. Units with fsed capacities of up to 3600 metric considay have been built. In tha mid-1970 s the Hysomer paraffin-isomarizaiion process, developed by Shell Research B.V.. was combined with the IsoSiv process in such a way tbet normal paraffins are nearly completely isomerized.131 The combination is called the Total Isomerization Process (TIP) and is shown schematically in Fig. 12,5-7. Product hom a TIP unit has a Rerearch OctHne Number of 88-92, compared to 79-82 for the product from a Hysomar unit alone. 

FIGURE 12.5-7 Total isomerization process. (From Ref. 12.5-14. copynghi Gulf Publishing Co., re-primed with permission.)... 

---