Shell higher olefin process isomerization

Shell Higher Olefin Process) plant (16,17). C -C alcohols are also produced by this process. Ethylene is first oligomerized to linear, even carbon—number alpha olefins using a nickel complex catalyst. After separation of portions of the a-olefins for sale, others, particularly C g and higher, are catalyticaHy isomerized to internal olefins, which are then disproportionated over a catalyst to a broad mixture of linear internal olefins. The desired fraction is... 

Alkenes. At present alkene isomerization is an important step in the production of detergent alkylates (Shell higher olefin process see Sections 12.3 and 13.1.3).264 265 Ethylene oligomerization in the presence of a nickel(O) catalyst yields terminal olefins with a broad distribution range. C4-C6 and C2o+ alkenes, which are not suitable for direct alkylate production, are isomerized and subsequently undergo metathesis. Isomerization is presumably carried out over a MgO catalyst. 

SHOP [Shell Higher Olefins Process] A process for producing a-olehns by oligomerizing ethylene, using a proprietary rhodium-phosphine catalyst. The a-olehns can then be isomerized to internal olefins as required. Invented by W. Keim in the Institut fur Technische Chemie und Petrolchemie, Aachen, West Germany, in the 1970s. The first plant was built in Geismar, LA, in 1979 the second in Stanlow, Cheshire, UK, in 1982. Licensed worldwide by a consortium of Union Carbide, Davy-McKee, and Johnson Matthey. 

The i-oleftns obtained have a purity of more than 95 molar per cent of terminal olefins and are devoid of branched structures or diolefinic or cyclic impurities. These z-olefms, which all have an even number of carbon atoms, are produced with yields that vary according to a statistical distribution, with a maximum of C, 0-C, 2-Cj, for example, if the final product is intended for the manufacture of linear alkylbenzene. Due to the low yield of a given cut, it is understandable that the upgrading of all the other fractions is economically necessary. Since the upgrading of the light and heavy fractions is often a problem. Shell in the United States has developed the SHOP (Shell Higher Olefin Process), in which these effluents are converted to a cut for detergents by isomerization and metathesis. 

In the Shell Higher Olefins Process (SHOP) a much more efficient catalyst based on transition metal compounds (probably nickel) is used to effect the oligomerization. Initially about 30% of the ethene is converted into the desired olefins. The remainder (C -Cj and above are isomerized to internal alkenes and then converted into more useful fractions by metathesis. 

Figure 6.16.5 Flow scheme of the Shell higher olefins process (SHOP) - P= purification I = isomerization M = metathesis. Adapted from Vogt (2005).

The most modern ethylene oligomerization process—SHOP (Shell higher olefin process)—consists of three steps ethylene oligomerization, oligomers isomerization and cometathesis (Figure 2) [291]. 

Other large-volnme producers of alcohols using the oxo process are BASF and Noroxo S. A. in western Europe. BASF and Noroxo S. A. convert both linear alpha olefins and other olefins using nonselective oxo catalysts resulting in much higher isomeric products than Shell s alcohols. 

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