C4 Isomerization

The purpose of the C4 Isomerization unit is to convert normal butane (n-C4) into isobutane to feed the alkylation unit.

Isobutane is produced in a variety of conversion units in a refinery. However, when a refinery has an alkylation unit there is usually a need to make additional isobutane "on purpose" to keep the alky full. This is done by isomerizing normal butane in a C4 Isomerization unit.

How it works

A normal butane feed stream is mixed with a small amount of hydrogen, raised to 200-400 degrees F (93-204 degrees C), and injected into a reactor vessel containing a platinum catalyst. The catalyst and heat convert the C4 molecules into the isomer isobutane. Typically, unreacted C4s are recycled to increase yield.

McKinsey uses cookies to improve site functionality, provide you with a better browsing experience, and to enable our partners to advertise to you. Detailed information on the use of cookies on this Site, and how you can decline them, is provided in our cookie policy. By using this Site or clicking on "OK", you consent to the use of cookies.