Dehydrogenation of Tertiary Amylenes (Shell Process) : Isoprene synthesis

t-Amylenes (2-methyl-1-butene and 2-methyl-2-butene) are produced in small amounts with olefins from steam cracking units. The amylenes are extracted from a C₅ fraction with aqueous sulfuric acid. Dehydrogenation of t-amylenes over a dehydrogenation catalyst produces isoprene. The overall conversion and recovery of t-amylenes is approximately 70%. The C5 olefin mixture can also be produced by the reaction of ethylene and propene using an acid catalyst.

The C₅ olefin mixture is then dehydrogenated to isoprene.