The Phillips Triolefin Process and OCT – The Propylene Story

What do you consider a large scale olefin metathesis reaction? It’s inexcusable that we’ve just celebrated our 1 year anniversary of ATM and we haven’t yet discussed the most successful industrial metathesis process (at least measured by amount of product formed each year), one whose history is intertwined with olefin metathesis itself. At its core, it’s the most simple olefin metathesis reaction you can imagine, the interconversion of ethylene, 2-butene, and propylene.

The Phillips Triolefin Process was developed at Phillips Petroleum in the 1960s. It used a heterogeneous WO3/SiO2 catalyst to convert propylene to ethylene and 2-butene, for which demand was then growing. The first plant to operate this process ran from 1966-1972 with an annual capacity of nearly 100,000 million lbs of ethylene and butene! Ultimately, the growth of polypropylene fueled increased demand for propylene, and the process was shut down. 

But olefin metathesis is an equilibrium reaction. Once the price of propylene rose high enough, running the Triolefin Process in reverse became attractive. Lyondell was the first to operate a plant based on this process. It opened in 1984 and eventually expanded to a capacity of just shy of a billion lbs of propylene per year (yes, that’s billion!).

Lummus Technology now offers the engineering and catalyst for this process, known as OCT® (for Olefins Conversion Technology) on plants producing well over 1.5 billion lbs per year of propylene. OCT® is now the fastest growing process for on-purpose propylene.

– Dwyer, C. L. Metathesis of Olefins. In Metal-catalysis in Industrial Organic Processes; Chiusoli, G. P., Maitlis, P. M., Eds.; Royal Society of Chemistry: Cambridge, United Kingdom, 2006; pp. 201-217.
– Weissermel, K.; Arpe, H.-J. Industrial Organic Chemistry, 4th edition; Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany, 2003; pp. 85-90.
– Witcoff, H. A.; Reuben, B. G.; Plotkin, J. S. Industrial Organic Chemicals, 2nd Edition; John Wiley & Sons, Inc.: Hoboken, (New Jersey) United States, 2004; p. 88.
– Henni, A. Downstream focus: Lummus Technology, Feb 10, 2010. Arabian Oil and Gas Web site. (accessed Sep 6, 2010).

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  1. says

    According to Lummus, metathesis of ethylene and butenes now exceed 6% of the global propylene. Because the supply of butenes is tightening worldwide due to both the increased demand for metathesis feedstocks and the increased demand for butadiene, there is a trend for C5 metathesis for increased propylene production. The C5 cut from steam crackers has not been used as a metathesis feedstock due to perceived issues surrounding the high concentrations of cyclopentadiene found in that stream.

  2. Suriye says

    Agree that Lummus heading to C5. However, C5-cut is quite small for steam cracker and trend to be less since most of steam cracker tread to utilize more LPG as a feedstock. So, the portion of C5 will be smaller and rarely to find eventually.

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