Isomerization Hysomer 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. 

The earliest industrial zeolitic isomerization process was the Hysomer process, formerly offered for license by Shell. Currently UOP offers a zeolite- and Pt-con-taining catalyst HS-10 in the fixed-bed UOP TIP process [3]. A similar catalyst Hysopar was introduced by Sud-Chemie [22] in the CKS Isom process (Cepsa-Kellogg-Sud Chemie). Recently there were reports of IMP-02 and CI-50 commercial catalysts from China [23] and Russia [24]. 

A noble metal on zeolite is applied in the Hysomer process to isomerize C5/C6 alkanes in the presence of hydrogen.260,261 The once-through isomerization increases the octane numbers by 10-12 numbers. When unreacted straight-chain alkanes, however, are removed (most economically by selective absorption with molecular sieve zeolites) and recycled, then complete isomerization can result in an increase in 20 octane numbers. ... 

As mentioned in part 7.2, reporting on the Shell Hysomer Process, the aromatics in the feed are quantitatively hydrogenated to the corresponding naphtenes and present no problems to the catalyst selectivity, even in concentrations of up to 2 wt.-% (4). The commercial performance of HYSOPAR includes experience with up to 5 wt.-% of benzene in the isomerization feed (4). 

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. 

The introduction of dual-function catalysts for naphtha lefomiing and the demand for high-octane gasoline led to further interest in isomerization. The platinum/alumina (cUorided) catalysts were a success despite the resulting lower conversion to high-octane products from the need to operate at higher temperatures. The Shell Hysomer process, which used a 5A-zeolite to separate low-octane paraffins from the product allowed operators to recycle unconverted feed and achieve almost 100% conversion. ... 

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. 

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. 

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