Processes Hysomer

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. ... 

The TIP process is a combination of Shell s Hysomer process and Union Carbide s ISOSIV process. Both processes are zeolite based. 

In the Hysomer process the catalyst is a Pt(0)-loaded zeolite of the H-mordenite type. The temperature applied has a strong bearing on the composition of the equilibrium mixture obtained, see Fig. 2.6 for the hexane isomers the lower the temperature applicable, the more dimethylbutanes are present. The temperature dependence is not easily explained, but it will be clear that a low temperature is favourable for the purpose of the process. 

In the TIP process the Hysomer process is combined with the ISOSIV process which separates normal paraffins from branched ones by selectively adsorbing the normal fraction into zeolite CaA (pressure swing adsorption). Ajfter desorption (by applying vacuum) the normal paraffins are recycled. A schematic view... 

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. ... 

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