Butane isomerization Shell process

Fiq. 12. Vapor-phase butane isomerization. Shell Isocel process. 

Fiq. 18. Liquid-phase butane isomerization. Shell antimony chloride process. 

Fig. 20. Process variables for butane isomerization. Shell liquid-phase process. Conditions (unless otherwise noted) temperature, 176°F. residence time, 13-15 minutes AlCU, 7.5 wt.% HCl, 4.0 wt.% catalyst-to-hydrocarbon ratio, 1/1.

The third liquid-phase butane-isomerization process, shown in Figure 5, was developed by Shell as an improvement over the original intermittent vapor-phase process. 

Pentane Isomerization. Pentane isomerization, although carried out on a much smaller scale, increased the critical supply of aviation gasolines toward the end of the war. Two pentane processes—one developed by Shell and one by Standard (Indiana) —were commercialized before the end of the war. The principal differences between the butane and pentane processes are the use in pentane isomerization of somewhat milder conditions and the use of an inhibitor to suppress side reactions, principally disproportionation. In general, the problems of the butane processes are inherent also in pentane isomerization, but the quality of the feed stocks is less important. Catalyst life is much... 

The third liquid-phase butane-isomerization process was developed by Shell Oil Company (16) as an improvement over the original intermittent vapor-phase process. The simplified flow diagram is shown in Figure 18. The aluminum chloride is handled, in this case, as an approximately 9% solution in relatively inert molten antimony trichloride the... 

One early limitation in the use of alkylation processes was a shortage of isobutane in refineries. In some refineries, however, further suppUes of isobutane could be extracted from natural gas. Where this was not possible, the butane in off-gas could be isomerized to isobutane using a new process which used an acid aluminum chloride catalyst. Shell, for example, operated an isomerization pilot plant at Pemis, in Holland, from 1939. ... 

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