Triolefin process olefin metathesis technology

Alkylation processes usually combine isobutane with an alkene or with mixed alkene streams (C3-C5 olefins from FCC units). The best octane ratings are attained when isobutane is alkylated with butylenes. Alkylation of higher-molecular-weight hydrocarbons (>C5) is less economic because of increased probability of side reactions. Phillips developed a technology that combines its triolefin process (metathesis of propylene to produce ethylene and 2-butenes) with alkylation since 2-butenes yield better alkylate than propylene.290 Since ethylene cannot be readily used in protic acid-catalyzed alkylations, a process employing AICI3 promoted by water was also developed.291... 

Early in 1962, following Phillips Management s decision to develop the Triolefin Process, laboratory studies were resumed and expanded. In addition to conducting a detailed investigation of cobalt molybdate catalyst systems, an extensive search for other catalyst compositions active for olefin metathesis was made. Concurrent with these investigations were studies designed to expand the scope and explore other applications of olefin metathesis reactions. Pilot plant development of Triolefin Process technology was initiated about six months after laboratory studies had been resumed. 

This process, called OCT (olefin conversion technology), formerly the Phillips Triolefin Process, which utilizes a heterogeneous catalyst system, was originally developed by Phillips Petroleum Co. for the conversion of propene into ethene and butene. The reaction takes place in a fixed-bed reactor over a mixture of the metathesis catalyst W03/S102 and the isomerization catalyst MgO at temperatures above 540 K and an overall pressure of approximately 30 bar [3]. 1-Butene present in the feedstock is isomerized to 2-butene as the original 2-butene is consumed in the metathesis reaction. 

Because olefin metathesis is an equilibrium reaction, the Triolefin Process can be mn in the reverse direction to produce propylene from 2-butene and ethylene. Lyondell licensed the Phillips Triolefin process and opened the first propylene plant based on this technology in 1984, eventually expanding capacity to 450 000 metric tons per year. In 1997, Lummus Technology, who engineered the first two applications under license from Phillips, purchased the technology from Phillips. The metathesis of ethylene and butenes to propylene is now commercialized as Olefins Conversion Technology (OCT )... 

The Phillips triolefin process [56] developed at Phillips Petroleum, used a heterogeneous WOj/SiOj catalyst in metathesis reaction to convert propene 127 into mixture of ethene 125 and 2-butene 126. As it is a reversible reaetion (Scheme 9.32) and the price of propene rose high, the reverse reaction of Philips process offered is now by using Lummus teehnology to produce propene known as Olefin Conversion Technology (OCT). 

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